Initial import

1 files changed, 2950 insertions, 0 deletions

diff --git a/drivers/tty/serial/ioc4_serial.c b/drivers/tty/serial/ioc4_serial.c
new file mode 100644
index 000000000..aa28209f4
--- /dev/null
+++ b/drivers/tty/serial/ioc4_serial.c
@@ -0,0 +1,2950 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2003-2006 Silicon Graphics, Inc.  All Rights Reserved.
+ */
+
+
+/*
+ * This file contains a module version of the ioc4 serial driver. This
+ * includes all the support functions needed (support functions, etc.)
+ * and the serial driver itself.
+ */
+#include <linux/errno.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/circ_buf.h>
+#include <linux/serial_reg.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/ioc4.h>
+#include <linux/serial_core.h>
+#include <linux/slab.h>
+
+/*
+ * interesting things about the ioc4
+ */
+
+#define IOC4_NUM_SERIAL_PORTS	4	/* max ports per card */
+#define IOC4_NUM_CARDS		8	/* max cards per partition */
+
+#define	GET_SIO_IR(_n)	(_n == 0) ? (IOC4_SIO_IR_S0) : \
+				(_n == 1) ? (IOC4_SIO_IR_S1) : \
+				(_n == 2) ? (IOC4_SIO_IR_S2) : \
+				(IOC4_SIO_IR_S3)
+
+#define	GET_OTHER_IR(_n)  (_n == 0) ? (IOC4_OTHER_IR_S0_MEMERR) : \
+				(_n == 1) ? (IOC4_OTHER_IR_S1_MEMERR) : \
+				(_n == 2) ? (IOC4_OTHER_IR_S2_MEMERR) : \
+				(IOC4_OTHER_IR_S3_MEMERR)
+
+
+/*
+ * All IOC4 registers are 32 bits wide.
+ */
+
+/*
+ * PCI Memory Space Map
+ */
+#define IOC4_PCI_ERR_ADDR_L     0x000	/* Low Error Address */
+#define IOC4_PCI_ERR_ADDR_VLD	        (0x1 << 0)
+#define IOC4_PCI_ERR_ADDR_MST_ID_MSK    (0xf << 1)
+#define IOC4_PCI_ERR_ADDR_MST_NUM_MSK   (0xe << 1)
+#define IOC4_PCI_ERR_ADDR_MST_TYP_MSK   (0x1 << 1)
+#define IOC4_PCI_ERR_ADDR_MUL_ERR       (0x1 << 5)
+#define IOC4_PCI_ERR_ADDR_ADDR_MSK      (0x3ffffff << 6)
+
+/* Interrupt types */
+#define	IOC4_SIO_INTR_TYPE	0
+#define	IOC4_OTHER_INTR_TYPE	1
+#define	IOC4_NUM_INTR_TYPES	2
+
+/* Bitmasks for IOC4_SIO_IR, IOC4_SIO_IEC, and IOC4_SIO_IES  */
+#define IOC4_SIO_IR_S0_TX_MT	   0x00000001	/* Serial port 0 TX empty */
+#define IOC4_SIO_IR_S0_RX_FULL	   0x00000002	/* Port 0 RX buf full */
+#define IOC4_SIO_IR_S0_RX_HIGH	   0x00000004	/* Port 0 RX hiwat */
+#define IOC4_SIO_IR_S0_RX_TIMER	   0x00000008	/* Port 0 RX timeout */
+#define IOC4_SIO_IR_S0_DELTA_DCD   0x00000010	/* Port 0 delta DCD */
+#define IOC4_SIO_IR_S0_DELTA_CTS   0x00000020	/* Port 0 delta CTS */
+#define IOC4_SIO_IR_S0_INT	   0x00000040	/* Port 0 pass-thru intr */
+#define IOC4_SIO_IR_S0_TX_EXPLICIT 0x00000080	/* Port 0 explicit TX thru */
+#define IOC4_SIO_IR_S1_TX_MT	   0x00000100	/* Serial port 1 */
+#define IOC4_SIO_IR_S1_RX_FULL	   0x00000200	/* */
+#define IOC4_SIO_IR_S1_RX_HIGH	   0x00000400	/* */
+#define IOC4_SIO_IR_S1_RX_TIMER	   0x00000800	/* */
+#define IOC4_SIO_IR_S1_DELTA_DCD   0x00001000	/* */
+#define IOC4_SIO_IR_S1_DELTA_CTS   0x00002000	/* */
+#define IOC4_SIO_IR_S1_INT	   0x00004000	/* */
+#define IOC4_SIO_IR_S1_TX_EXPLICIT 0x00008000	/* */
+#define IOC4_SIO_IR_S2_TX_MT	   0x00010000	/* Serial port 2 */
+#define IOC4_SIO_IR_S2_RX_FULL	   0x00020000	/* */
+#define IOC4_SIO_IR_S2_RX_HIGH	   0x00040000	/* */
+#define IOC4_SIO_IR_S2_RX_TIMER	   0x00080000	/* */
+#define IOC4_SIO_IR_S2_DELTA_DCD   0x00100000	/* */
+#define IOC4_SIO_IR_S2_DELTA_CTS   0x00200000	/* */
+#define IOC4_SIO_IR_S2_INT	   0x00400000	/* */
+#define IOC4_SIO_IR_S2_TX_EXPLICIT 0x00800000	/* */
+#define IOC4_SIO_IR_S3_TX_MT	   0x01000000	/* Serial port 3 */
+#define IOC4_SIO_IR_S3_RX_FULL	   0x02000000	/* */
+#define IOC4_SIO_IR_S3_RX_HIGH	   0x04000000	/* */
+#define IOC4_SIO_IR_S3_RX_TIMER	   0x08000000	/* */
+#define IOC4_SIO_IR_S3_DELTA_DCD   0x10000000	/* */
+#define IOC4_SIO_IR_S3_DELTA_CTS   0x20000000	/* */
+#define IOC4_SIO_IR_S3_INT	   0x40000000	/* */
+#define IOC4_SIO_IR_S3_TX_EXPLICIT 0x80000000	/* */
+
+/* Per device interrupt masks */
+#define IOC4_SIO_IR_S0		(IOC4_SIO_IR_S0_TX_MT | \
+				 IOC4_SIO_IR_S0_RX_FULL | \
+				 IOC4_SIO_IR_S0_RX_HIGH | \
+				 IOC4_SIO_IR_S0_RX_TIMER | \
+				 IOC4_SIO_IR_S0_DELTA_DCD | \
+				 IOC4_SIO_IR_S0_DELTA_CTS | \
+				 IOC4_SIO_IR_S0_INT | \
+				 IOC4_SIO_IR_S0_TX_EXPLICIT)
+#define IOC4_SIO_IR_S1		(IOC4_SIO_IR_S1_TX_MT | \
+				 IOC4_SIO_IR_S1_RX_FULL | \
+				 IOC4_SIO_IR_S1_RX_HIGH | \
+				 IOC4_SIO_IR_S1_RX_TIMER | \
+				 IOC4_SIO_IR_S1_DELTA_DCD | \
+				 IOC4_SIO_IR_S1_DELTA_CTS | \
+				 IOC4_SIO_IR_S1_INT | \
+				 IOC4_SIO_IR_S1_TX_EXPLICIT)
+#define IOC4_SIO_IR_S2		(IOC4_SIO_IR_S2_TX_MT | \
+				 IOC4_SIO_IR_S2_RX_FULL | \
+				 IOC4_SIO_IR_S2_RX_HIGH | \
+				 IOC4_SIO_IR_S2_RX_TIMER | \
+				 IOC4_SIO_IR_S2_DELTA_DCD | \
+				 IOC4_SIO_IR_S2_DELTA_CTS | \
+				 IOC4_SIO_IR_S2_INT | \
+				 IOC4_SIO_IR_S2_TX_EXPLICIT)
+#define IOC4_SIO_IR_S3		(IOC4_SIO_IR_S3_TX_MT | \
+				 IOC4_SIO_IR_S3_RX_FULL | \
+				 IOC4_SIO_IR_S3_RX_HIGH | \
+				 IOC4_SIO_IR_S3_RX_TIMER | \
+				 IOC4_SIO_IR_S3_DELTA_DCD | \
+				 IOC4_SIO_IR_S3_DELTA_CTS | \
+				 IOC4_SIO_IR_S3_INT | \
+				 IOC4_SIO_IR_S3_TX_EXPLICIT)
+
+/* Bitmasks for IOC4_OTHER_IR, IOC4_OTHER_IEC, and IOC4_OTHER_IES  */
+#define IOC4_OTHER_IR_ATA_INT		0x00000001  /* ATAPI intr pass-thru */
+#define IOC4_OTHER_IR_ATA_MEMERR	0x00000002  /* ATAPI DMA PCI error */
+#define IOC4_OTHER_IR_S0_MEMERR		0x00000004  /* Port 0 PCI error */
+#define IOC4_OTHER_IR_S1_MEMERR		0x00000008  /* Port 1 PCI error */
+#define IOC4_OTHER_IR_S2_MEMERR		0x00000010  /* Port 2 PCI error */
+#define IOC4_OTHER_IR_S3_MEMERR		0x00000020  /* Port 3 PCI error */
+#define IOC4_OTHER_IR_KBD_INT		0x00000040  /* Keyboard/mouse */
+#define IOC4_OTHER_IR_RESERVED		0x007fff80  /* Reserved */
+#define IOC4_OTHER_IR_RT_INT		0x00800000  /* INT_OUT section output */
+#define IOC4_OTHER_IR_GEN_INT		0xff000000  /* Generic pins */
+
+#define IOC4_OTHER_IR_SER_MEMERR (IOC4_OTHER_IR_S0_MEMERR | IOC4_OTHER_IR_S1_MEMERR | \
+				  IOC4_OTHER_IR_S2_MEMERR | IOC4_OTHER_IR_S3_MEMERR)
+
+/* Bitmasks for IOC4_SIO_CR */
+#define IOC4_SIO_CR_CMD_PULSE_SHIFT              0  /* byte bus strobe shift */
+#define IOC4_SIO_CR_ARB_DIAG_TX0	0x00000000
+#define IOC4_SIO_CR_ARB_DIAG_RX0	0x00000010
+#define IOC4_SIO_CR_ARB_DIAG_TX1	0x00000020
+#define IOC4_SIO_CR_ARB_DIAG_RX1	0x00000030
+#define IOC4_SIO_CR_ARB_DIAG_TX2	0x00000040
+#define IOC4_SIO_CR_ARB_DIAG_RX2	0x00000050
+#define IOC4_SIO_CR_ARB_DIAG_TX3	0x00000060
+#define IOC4_SIO_CR_ARB_DIAG_RX3	0x00000070
+#define IOC4_SIO_CR_SIO_DIAG_IDLE	0x00000080  /* 0 -> active request among
+							   serial ports (ro) */
+/* Defs for some of the generic I/O pins */
+#define IOC4_GPCR_UART0_MODESEL	   0x10	/* Pin is output to port 0
+						   mode sel */
+#define IOC4_GPCR_UART1_MODESEL	   0x20	/* Pin is output to port 1
+						   mode sel */
+#define IOC4_GPCR_UART2_MODESEL	   0x40	/* Pin is output to port 2
+						   mode sel */
+#define IOC4_GPCR_UART3_MODESEL	   0x80	/* Pin is output to port 3
+						   mode sel */
+
+#define IOC4_GPPR_UART0_MODESEL_PIN   4	/* GIO pin controlling
+					   uart 0 mode select */
+#define IOC4_GPPR_UART1_MODESEL_PIN   5	/* GIO pin controlling
+					   uart 1 mode select */
+#define IOC4_GPPR_UART2_MODESEL_PIN   6	/* GIO pin controlling
+					   uart 2 mode select */
+#define IOC4_GPPR_UART3_MODESEL_PIN   7	/* GIO pin controlling
+					   uart 3 mode select */
+
+/* Bitmasks for serial RX status byte */
+#define IOC4_RXSB_OVERRUN       0x01	/* Char(s) lost */
+#define IOC4_RXSB_PAR_ERR	0x02	/* Parity error */
+#define IOC4_RXSB_FRAME_ERR	0x04	/* Framing error */
+#define IOC4_RXSB_BREAK	        0x08	/* Break character */
+#define IOC4_RXSB_CTS	        0x10	/* State of CTS */
+#define IOC4_RXSB_DCD	        0x20	/* State of DCD */
+#define IOC4_RXSB_MODEM_VALID   0x40	/* DCD, CTS, and OVERRUN are valid */
+#define IOC4_RXSB_DATA_VALID    0x80	/* Data byte, FRAME_ERR PAR_ERR
+					 * & BREAK valid */
+
+/* Bitmasks for serial TX control byte */
+#define IOC4_TXCB_INT_WHEN_DONE 0x20	/* Interrupt after this byte is sent */
+#define IOC4_TXCB_INVALID	0x00	/* Byte is invalid */
+#define IOC4_TXCB_VALID	        0x40	/* Byte is valid */
+#define IOC4_TXCB_MCR	        0x80	/* Data<7:0> to modem control reg */
+#define IOC4_TXCB_DELAY	        0xc0	/* Delay data<7:0> mSec */
+
+/* Bitmasks for IOC4_SBBR_L */
+#define IOC4_SBBR_L_SIZE	0x00000001  /* 0 == 1KB rings, 1 == 4KB rings */
+
+/* Bitmasks for IOC4_SSCR_<3:0> */
+#define IOC4_SSCR_RX_THRESHOLD  0x000001ff  /* Hiwater mark */
+#define IOC4_SSCR_TX_TIMER_BUSY 0x00010000  /* TX timer in progress */
+#define IOC4_SSCR_HFC_EN	0x00020000  /* Hardware flow control enabled */
+#define IOC4_SSCR_RX_RING_DCD   0x00040000  /* Post RX record on delta-DCD */
+#define IOC4_SSCR_RX_RING_CTS   0x00080000  /* Post RX record on delta-CTS */
+#define IOC4_SSCR_DIAG	        0x00200000  /* Bypass clock divider for sim */
+#define IOC4_SSCR_RX_DRAIN	0x08000000  /* Drain RX buffer to memory */
+#define IOC4_SSCR_DMA_EN	0x10000000  /* Enable ring buffer DMA */
+#define IOC4_SSCR_DMA_PAUSE	0x20000000  /* Pause DMA */
+#define IOC4_SSCR_PAUSE_STATE   0x40000000  /* Sets when PAUSE takes effect */
+#define IOC4_SSCR_RESET	        0x80000000  /* Reset DMA channels */
+
+/* All producer/comsumer pointers are the same bitfield */
+#define IOC4_PROD_CONS_PTR_4K   0x00000ff8	/* For 4K buffers */
+#define IOC4_PROD_CONS_PTR_1K   0x000003f8	/* For 1K buffers */
+#define IOC4_PROD_CONS_PTR_OFF           3
+
+/* Bitmasks for IOC4_SRCIR_<3:0> */
+#define IOC4_SRCIR_ARM	        0x80000000	/* Arm RX timer */
+
+/* Bitmasks for IOC4_SHADOW_<3:0> */
+#define IOC4_SHADOW_DR	 0x00000001	/* Data ready */
+#define IOC4_SHADOW_OE	 0x00000002	/* Overrun error */
+#define IOC4_SHADOW_PE	 0x00000004	/* Parity error */
+#define IOC4_SHADOW_FE	 0x00000008	/* Framing error */
+#define IOC4_SHADOW_BI	 0x00000010	/* Break interrupt */
+#define IOC4_SHADOW_THRE 0x00000020	/* Xmit holding register empty */
+#define IOC4_SHADOW_TEMT 0x00000040	/* Xmit shift register empty */
+#define IOC4_SHADOW_RFCE 0x00000080	/* Char in RX fifo has an error */
+#define IOC4_SHADOW_DCTS 0x00010000	/* Delta clear to send */
+#define IOC4_SHADOW_DDCD 0x00080000	/* Delta data carrier detect */
+#define IOC4_SHADOW_CTS	 0x00100000	/* Clear to send */
+#define IOC4_SHADOW_DCD	 0x00800000	/* Data carrier detect */
+#define IOC4_SHADOW_DTR	 0x01000000	/* Data terminal ready */
+#define IOC4_SHADOW_RTS	 0x02000000	/* Request to send */
+#define IOC4_SHADOW_OUT1 0x04000000	/* 16550 OUT1 bit */
+#define IOC4_SHADOW_OUT2 0x08000000	/* 16550 OUT2 bit */
+#define IOC4_SHADOW_LOOP 0x10000000	/* Loopback enabled */
+
+/* Bitmasks for IOC4_SRTR_<3:0> */
+#define IOC4_SRTR_CNT	        0x00000fff	/* Reload value for RX timer */
+#define IOC4_SRTR_CNT_VAL	0x0fff0000	/* Current value of RX timer */
+#define IOC4_SRTR_CNT_VAL_SHIFT         16
+#define IOC4_SRTR_HZ                 16000	/* SRTR clock frequency */
+
+/* Serial port register map used for DMA and PIO serial I/O */
+struct ioc4_serialregs {
+	uint32_t sscr;
+	uint32_t stpir;
+	uint32_t stcir;
+	uint32_t srpir;
+	uint32_t srcir;
+	uint32_t srtr;
+	uint32_t shadow;
+};
+
+/* IOC4 UART register map */
+struct ioc4_uartregs {
+	char i4u_lcr;
+	union {
+		char iir;	/* read only */
+		char fcr;	/* write only */
+	} u3;
+	union {
+		char ier;	/* DLAB == 0 */
+		char dlm;	/* DLAB == 1 */
+	} u2;
+	union {
+		char rbr;	/* read only, DLAB == 0 */
+		char thr;	/* write only, DLAB == 0 */
+		char dll;	/* DLAB == 1 */
+	} u1;
+	char i4u_scr;
+	char i4u_msr;
+	char i4u_lsr;
+	char i4u_mcr;
+};
+
+/* short names */
+#define i4u_dll u1.dll
+#define i4u_ier u2.ier
+#define i4u_dlm u2.dlm
+#define i4u_fcr u3.fcr
+
+/* Serial port registers used for DMA serial I/O */
+struct ioc4_serial {
+	uint32_t sbbr01_l;
+	uint32_t sbbr01_h;
+	uint32_t sbbr23_l;
+	uint32_t sbbr23_h;
+
+	struct ioc4_serialregs port_0;
+	struct ioc4_serialregs port_1;
+	struct ioc4_serialregs port_2;
+	struct ioc4_serialregs port_3;
+	struct ioc4_uartregs uart_0;
+	struct ioc4_uartregs uart_1;
+	struct ioc4_uartregs uart_2;
+	struct ioc4_uartregs uart_3;
+};
+
+/* UART clock speed */
+#define IOC4_SER_XIN_CLK_66     66666667
+#define IOC4_SER_XIN_CLK_33     33333333
+
+#define IOC4_W_IES		0
+#define IOC4_W_IEC		1
+
+typedef void ioc4_intr_func_f(void *, uint32_t);
+typedef ioc4_intr_func_f *ioc4_intr_func_t;
+
+static unsigned int Num_of_ioc4_cards;
+
+/* defining this will get you LOTS of great debug info */
+//#define DEBUG_INTERRUPTS
+#define DPRINT_CONFIG(_x...)	;
+//#define DPRINT_CONFIG(_x...)	printk _x
+
+/* number of characters left in xmit buffer before we ask for more */
+#define WAKEUP_CHARS	256
+
+/* number of characters we want to transmit to the lower level at a time */
+#define IOC4_MAX_CHARS	256
+#define IOC4_FIFO_CHARS	255
+
+/* Device name we're using */
+#define DEVICE_NAME_RS232  "ttyIOC"
+#define DEVICE_NAME_RS422  "ttyAIOC"
+#define DEVICE_MAJOR	   204
+#define DEVICE_MINOR_RS232 50
+#define DEVICE_MINOR_RS422 84
+
+
+/* register offsets */
+#define IOC4_SERIAL_OFFSET	0x300
+
+/* flags for next_char_state */
+#define NCS_BREAK	0x1
+#define NCS_PARITY	0x2
+#define NCS_FRAMING	0x4
+#define NCS_OVERRUN	0x8
+
+/* cause we need SOME parameters ... */
+#define MIN_BAUD_SUPPORTED	1200
+#define MAX_BAUD_SUPPORTED	115200
+
+/* protocol types supported */
+#define PROTO_RS232	3
+#define PROTO_RS422	7
+
+/* Notification types */
+#define N_DATA_READY	0x01
+#define N_OUTPUT_LOWAT	0x02
+#define N_BREAK		0x04
+#define N_PARITY_ERROR	0x08
+#define N_FRAMING_ERROR	0x10
+#define N_OVERRUN_ERROR	0x20
+#define N_DDCD		0x40
+#define N_DCTS		0x80
+
+#define N_ALL_INPUT	(N_DATA_READY | N_BREAK |			\
+			 N_PARITY_ERROR | N_FRAMING_ERROR |		\
+			 N_OVERRUN_ERROR | N_DDCD | N_DCTS)
+
+#define N_ALL_OUTPUT	N_OUTPUT_LOWAT
+
+#define N_ALL_ERRORS	(N_PARITY_ERROR | N_FRAMING_ERROR | N_OVERRUN_ERROR)
+
+#define N_ALL		(N_DATA_READY | N_OUTPUT_LOWAT | N_BREAK |	\
+			 N_PARITY_ERROR | N_FRAMING_ERROR |		\
+			 N_OVERRUN_ERROR | N_DDCD | N_DCTS)
+
+#define SER_DIVISOR(_x, clk)		(((clk) + (_x) * 8) / ((_x) * 16))
+#define DIVISOR_TO_BAUD(div, clk)	((clk) / 16 / (div))
+
+/* Some masks */
+#define LCR_MASK_BITS_CHAR	(UART_LCR_WLEN5 | UART_LCR_WLEN6 \
+					| UART_LCR_WLEN7 | UART_LCR_WLEN8)
+#define LCR_MASK_STOP_BITS	(UART_LCR_STOP)
+
+#define PENDING(_p)	(readl(&(_p)->ip_mem->sio_ir.raw) & _p->ip_ienb)
+#define READ_SIO_IR(_p) readl(&(_p)->ip_mem->sio_ir.raw)
+
+/* Default to 4k buffers */
+#ifdef IOC4_1K_BUFFERS
+#define RING_BUF_SIZE 1024
+#define IOC4_BUF_SIZE_BIT 0
+#define PROD_CONS_MASK IOC4_PROD_CONS_PTR_1K
+#else
+#define RING_BUF_SIZE 4096
+#define IOC4_BUF_SIZE_BIT IOC4_SBBR_L_SIZE
+#define PROD_CONS_MASK IOC4_PROD_CONS_PTR_4K
+#endif
+
+#define TOTAL_RING_BUF_SIZE (RING_BUF_SIZE * 4)
+
+/*
+ * This is the entry saved by the driver - one per card
+ */
+
+#define UART_PORT_MIN		0
+#define UART_PORT_RS232		UART_PORT_MIN
+#define UART_PORT_RS422		1
+#define UART_PORT_COUNT		2	/* one for each mode */
+
+struct ioc4_control {
+	int ic_irq;
+	struct {
+		/* uart ports are allocated here - 1 for rs232, 1 for rs422 */
+		struct uart_port icp_uart_port[UART_PORT_COUNT];
+		/* Handy reference material */
+		struct ioc4_port *icp_port;
+	} ic_port[IOC4_NUM_SERIAL_PORTS];
+	struct ioc4_soft *ic_soft;
+};
+
+/*
+ * per-IOC4 data structure
+ */
+#define MAX_IOC4_INTR_ENTS	(8 * sizeof(uint32_t))
+struct ioc4_soft {
+	struct ioc4_misc_regs __iomem *is_ioc4_misc_addr;
+	struct ioc4_serial __iomem *is_ioc4_serial_addr;
+
+	/* Each interrupt type has an entry in the array */
+	struct ioc4_intr_type {
+
+		/*
+		 * Each in-use entry in this array contains at least
+		 * one nonzero bit in sd_bits; no two entries in this
+		 * array have overlapping sd_bits values.
+		 */
+		struct ioc4_intr_info {
+			uint32_t sd_bits;
+			ioc4_intr_func_f *sd_intr;
+			void *sd_info;
+		} is_intr_info[MAX_IOC4_INTR_ENTS];
+
+		/* Number of entries active in the above array */
+		atomic_t is_num_intrs;
+	} is_intr_type[IOC4_NUM_INTR_TYPES];
+
+	/* is_ir_lock must be held while
+	 * modifying sio_ie values, so
+	 * we can be sure that sio_ie is
+	 * not changing when we read it
+	 * along with sio_ir.
+	 */
+	spinlock_t is_ir_lock;	/* SIO_IE[SC] mod lock */
+};
+
+/* Local port info for each IOC4 serial ports */
+struct ioc4_port {
+	struct uart_port *ip_port;	/* current active port ptr */
+	/* Ptrs for all ports */
+	struct uart_port *ip_all_ports[UART_PORT_COUNT];
+	/* Back ptrs for this port */
+	struct ioc4_control *ip_control;
+	struct pci_dev *ip_pdev;
+	struct ioc4_soft *ip_ioc4_soft;
+
+	/* pci mem addresses */
+	struct ioc4_misc_regs __iomem *ip_mem;
+	struct ioc4_serial __iomem *ip_serial;
+	struct ioc4_serialregs __iomem *ip_serial_regs;
+	struct ioc4_uartregs __iomem *ip_uart_regs;
+
+	/* Ring buffer page for this port */
+	dma_addr_t ip_dma_ringbuf;
+	/* vaddr of ring buffer */
+	struct ring_buffer *ip_cpu_ringbuf;
+
+	/* Rings for this port */
+	struct ring *ip_inring;
+	struct ring *ip_outring;
+
+	/* Hook to port specific values */
+	struct hooks *ip_hooks;
+
+	spinlock_t ip_lock;
+
+	/* Various rx/tx parameters */
+	int ip_baud;
+	int ip_tx_lowat;
+	int ip_rx_timeout;
+
+	/* Copy of notification bits */
+	int ip_notify;
+
+	/* Shadow copies of various registers so we don't need to PIO
+	 * read them constantly
+	 */
+	uint32_t ip_ienb;	/* Enabled interrupts */
+	uint32_t ip_sscr;
+	uint32_t ip_tx_prod;
+	uint32_t ip_rx_cons;
+	int ip_pci_bus_speed;
+	unsigned char ip_flags;
+};
+
+/* tx low water mark.  We need to notify the driver whenever tx is getting
+ * close to empty so it can refill the tx buffer and keep things going.
+ * Let's assume that if we interrupt 1 ms before the tx goes idle, we'll
+ * have no trouble getting in more chars in time (I certainly hope so).
+ */
+#define TX_LOWAT_LATENCY      1000
+#define TX_LOWAT_HZ          (1000000 / TX_LOWAT_LATENCY)
+#define TX_LOWAT_CHARS(baud) (baud / 10 / TX_LOWAT_HZ)
+
+/* Flags per port */
+#define INPUT_HIGH	0x01
+#define DCD_ON		0x02
+#define LOWAT_WRITTEN	0x04
+#define READ_ABORTED	0x08
+#define PORT_ACTIVE	0x10
+#define PORT_INACTIVE	0	/* This is the value when "off" */
+
+
+/* Since each port has different register offsets and bitmasks
+ * for everything, we'll store those that we need in tables so we
+ * don't have to be constantly checking the port we are dealing with.
+ */
+struct hooks {
+	uint32_t intr_delta_dcd;
+	uint32_t intr_delta_cts;
+	uint32_t intr_tx_mt;
+	uint32_t intr_rx_timer;
+	uint32_t intr_rx_high;
+	uint32_t intr_tx_explicit;
+	uint32_t intr_dma_error;
+	uint32_t intr_clear;
+	uint32_t intr_all;
+	int rs422_select_pin;
+};
+
+static struct hooks hooks_array[IOC4_NUM_SERIAL_PORTS] = {
+	/* Values for port 0 */
+	{
+	 IOC4_SIO_IR_S0_DELTA_DCD, IOC4_SIO_IR_S0_DELTA_CTS,
+	 IOC4_SIO_IR_S0_TX_MT, IOC4_SIO_IR_S0_RX_TIMER,
+	 IOC4_SIO_IR_S0_RX_HIGH, IOC4_SIO_IR_S0_TX_EXPLICIT,
+	 IOC4_OTHER_IR_S0_MEMERR,
+	 (IOC4_SIO_IR_S0_TX_MT | IOC4_SIO_IR_S0_RX_FULL |
+	  IOC4_SIO_IR_S0_RX_HIGH | IOC4_SIO_IR_S0_RX_TIMER |
+	  IOC4_SIO_IR_S0_DELTA_DCD | IOC4_SIO_IR_S0_DELTA_CTS |
+	  IOC4_SIO_IR_S0_INT | IOC4_SIO_IR_S0_TX_EXPLICIT),
+	 IOC4_SIO_IR_S0, IOC4_GPPR_UART0_MODESEL_PIN,
+	 },
+
+	/* Values for port 1 */
+	{
+	 IOC4_SIO_IR_S1_DELTA_DCD, IOC4_SIO_IR_S1_DELTA_CTS,
+	 IOC4_SIO_IR_S1_TX_MT, IOC4_SIO_IR_S1_RX_TIMER,
+	 IOC4_SIO_IR_S1_RX_HIGH, IOC4_SIO_IR_S1_TX_EXPLICIT,
+	 IOC4_OTHER_IR_S1_MEMERR,
+	 (IOC4_SIO_IR_S1_TX_MT | IOC4_SIO_IR_S1_RX_FULL |
+	  IOC4_SIO_IR_S1_RX_HIGH | IOC4_SIO_IR_S1_RX_TIMER |
+	  IOC4_SIO_IR_S1_DELTA_DCD | IOC4_SIO_IR_S1_DELTA_CTS |
+	  IOC4_SIO_IR_S1_INT | IOC4_SIO_IR_S1_TX_EXPLICIT),
+	 IOC4_SIO_IR_S1, IOC4_GPPR_UART1_MODESEL_PIN,
+	 },
+
+	/* Values for port 2 */
+	{
+	 IOC4_SIO_IR_S2_DELTA_DCD, IOC4_SIO_IR_S2_DELTA_CTS,
+	 IOC4_SIO_IR_S2_TX_MT, IOC4_SIO_IR_S2_RX_TIMER,
+	 IOC4_SIO_IR_S2_RX_HIGH, IOC4_SIO_IR_S2_TX_EXPLICIT,
+	 IOC4_OTHER_IR_S2_MEMERR,
+	 (IOC4_SIO_IR_S2_TX_MT | IOC4_SIO_IR_S2_RX_FULL |
+	  IOC4_SIO_IR_S2_RX_HIGH | IOC4_SIO_IR_S2_RX_TIMER |
+	  IOC4_SIO_IR_S2_DELTA_DCD | IOC4_SIO_IR_S2_DELTA_CTS |
+	  IOC4_SIO_IR_S2_INT | IOC4_SIO_IR_S2_TX_EXPLICIT),
+	 IOC4_SIO_IR_S2, IOC4_GPPR_UART2_MODESEL_PIN,
+	 },
+
+	/* Values for port 3 */
+	{
+	 IOC4_SIO_IR_S3_DELTA_DCD, IOC4_SIO_IR_S3_DELTA_CTS,
+	 IOC4_SIO_IR_S3_TX_MT, IOC4_SIO_IR_S3_RX_TIMER,
+	 IOC4_SIO_IR_S3_RX_HIGH, IOC4_SIO_IR_S3_TX_EXPLICIT,
+	 IOC4_OTHER_IR_S3_MEMERR,
+	 (IOC4_SIO_IR_S3_TX_MT | IOC4_SIO_IR_S3_RX_FULL |
+	  IOC4_SIO_IR_S3_RX_HIGH | IOC4_SIO_IR_S3_RX_TIMER |
+	  IOC4_SIO_IR_S3_DELTA_DCD | IOC4_SIO_IR_S3_DELTA_CTS |
+	  IOC4_SIO_IR_S3_INT | IOC4_SIO_IR_S3_TX_EXPLICIT),
+	 IOC4_SIO_IR_S3, IOC4_GPPR_UART3_MODESEL_PIN,
+	 }
+};
+
+/* A ring buffer entry */
+struct ring_entry {
+	union {
+		struct {
+			uint32_t alldata;
+			uint32_t allsc;
+		} all;
+		struct {
+			char data[4];	/* data bytes */
+			char sc[4];	/* status/control */
+		} s;
+	} u;
+};
+
+/* Test the valid bits in any of the 4 sc chars using "allsc" member */
+#define RING_ANY_VALID \
+	((uint32_t)(IOC4_RXSB_MODEM_VALID | IOC4_RXSB_DATA_VALID) * 0x01010101)
+
+#define ring_sc     u.s.sc
+#define ring_data   u.s.data
+#define ring_allsc  u.all.allsc
+
+/* Number of entries per ring buffer. */
+#define ENTRIES_PER_RING (RING_BUF_SIZE / (int) sizeof(struct ring_entry))
+
+/* An individual ring */
+struct ring {
+	struct ring_entry entries[ENTRIES_PER_RING];
+};
+
+/* The whole enchilada */
+struct ring_buffer {
+	struct ring TX_0_OR_2;
+	struct ring RX_0_OR_2;
+	struct ring TX_1_OR_3;
+	struct ring RX_1_OR_3;
+};
+
+/* Get a ring from a port struct */
+#define RING(_p, _wh)	&(((struct ring_buffer *)((_p)->ip_cpu_ringbuf))->_wh)
+
+/* Infinite loop detection.
+ */
+#define MAXITER 10000000
+
+/* Prototypes */
+static void receive_chars(struct uart_port *);
+static void handle_intr(void *arg, uint32_t sio_ir);
+
+/*
+ * port_is_active - determines if this port is currently active
+ * @port: ptr to soft struct for this port
+ * @uart_port: uart port to test for
+ */
+static inline int port_is_active(struct ioc4_port *port,
+		struct uart_port *uart_port)
+{
+	if (port) {
+		if ((port->ip_flags & PORT_ACTIVE)
+					&& (port->ip_port == uart_port))
+			return 1;
+	}
+	return 0;
+}
+
+
+/**
+ * write_ireg - write the interrupt regs
+ * @ioc4_soft: ptr to soft struct for this port
+ * @val: value to write
+ * @which: which register
+ * @type: which ireg set
+ */
+static inline void
+write_ireg(struct ioc4_soft *ioc4_soft, uint32_t val, int which, int type)
+{
+	struct ioc4_misc_regs __iomem *mem = ioc4_soft->is_ioc4_misc_addr;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ioc4_soft->is_ir_lock, flags);
+
+	switch (type) {
+	case IOC4_SIO_INTR_TYPE:
+		switch (which) {
+		case IOC4_W_IES:
+			writel(val, &mem->sio_ies.raw);
+			break;
+
+		case IOC4_W_IEC:
+			writel(val, &mem->sio_iec.raw);
+			break;
+		}
+		break;
+
+	case IOC4_OTHER_INTR_TYPE:
+		switch (which) {
+		case IOC4_W_IES:
+			writel(val, &mem->other_ies.raw);
+			break;
+
+		case IOC4_W_IEC:
+			writel(val, &mem->other_iec.raw);
+			break;
+		}
+		break;
+
+	default:
+		break;
+	}
+	spin_unlock_irqrestore(&ioc4_soft->is_ir_lock, flags);
+}
+
+/**
+ * set_baud - Baud rate setting code
+ * @port: port to set
+ * @baud: baud rate to use
+ */
+static int set_baud(struct ioc4_port *port, int baud)
+{
+	int actual_baud;
+	int diff;
+	int lcr;
+	unsigned short divisor;
+	struct ioc4_uartregs __iomem *uart;
+
+	divisor = SER_DIVISOR(baud, port->ip_pci_bus_speed);
+	if (!divisor)
+		return 1;
+	actual_baud = DIVISOR_TO_BAUD(divisor, port->ip_pci_bus_speed);
+
+	diff = actual_baud - baud;
+	if (diff < 0)
+		diff = -diff;
+
+	/* If we're within 1%, we've found a match */
+	if (diff * 100 > actual_baud)
+		return 1;
+
+	uart = port->ip_uart_regs;
+	lcr = readb(&uart->i4u_lcr);
+	writeb(lcr | UART_LCR_DLAB, &uart->i4u_lcr);
+	writeb((unsigned char)divisor, &uart->i4u_dll);
+	writeb((unsigned char)(divisor >> 8), &uart->i4u_dlm);
+	writeb(lcr, &uart->i4u_lcr);
+	return 0;
+}
+
+
+/**
+ * get_ioc4_port - given a uart port, return the control structure
+ * @port: uart port
+ * @set: set this port as current
+ */
+static struct ioc4_port *get_ioc4_port(struct uart_port *the_port, int set)
+{
+	struct ioc4_driver_data *idd = dev_get_drvdata(the_port->dev);
+	struct ioc4_control *control = idd->idd_serial_data;
+	struct ioc4_port *port;
+	int port_num, port_type;
+
+	if (control) {
+		for ( port_num = 0; port_num < IOC4_NUM_SERIAL_PORTS;
+							port_num++ ) {
+			port = control->ic_port[port_num].icp_port;
+			if (!port)
+				continue;
+			for (port_type = UART_PORT_MIN;
+						port_type < UART_PORT_COUNT;
+						port_type++) {
+				if (the_port == port->ip_all_ports
+							[port_type]) {
+					/* set local copy */
+					if (set) {
+						port->ip_port = the_port;
+					}
+					return port;
+				}
+			}
+		}
+	}
+	return NULL;
+}
+
+/* The IOC4 hardware provides no atomic way to determine if interrupts
+ * are pending since two reads are required to do so.  The handler must
+ * read the SIO_IR and the SIO_IES, and take the logical and of the
+ * two.  When this value is zero, all interrupts have been serviced and
+ * the handler may return.
+ *
+ * This has the unfortunate "hole" that, if some other CPU or
+ * some other thread or some higher level interrupt manages to
+ * modify SIO_IE between our reads of SIO_IR and SIO_IE, we may
+ * think we have observed SIO_IR&SIO_IE==0 when in fact this
+ * condition never really occurred.
+ *
+ * To solve this, we use a simple spinlock that must be held
+ * whenever modifying SIO_IE; holding this lock while observing
+ * both SIO_IR and SIO_IE guarantees that we do not falsely
+ * conclude that no enabled interrupts are pending.
+ */
+
+static inline uint32_t
+pending_intrs(struct ioc4_soft *soft, int type)
+{
+	struct ioc4_misc_regs __iomem *mem = soft->is_ioc4_misc_addr;
+	unsigned long flag;
+	uint32_t intrs = 0;
+
+	BUG_ON(!((type == IOC4_SIO_INTR_TYPE)
+	       || (type == IOC4_OTHER_INTR_TYPE)));
+
+	spin_lock_irqsave(&soft->is_ir_lock, flag);
+
+	switch (type) {
+	case IOC4_SIO_INTR_TYPE:
+		intrs = readl(&mem->sio_ir.raw) & readl(&mem->sio_ies.raw);
+		break;
+
+	case IOC4_OTHER_INTR_TYPE:
+		intrs = readl(&mem->other_ir.raw) & readl(&mem->other_ies.raw);
+
+		/* Don't process any ATA interrupte */
+		intrs &= ~(IOC4_OTHER_IR_ATA_INT | IOC4_OTHER_IR_ATA_MEMERR);
+		break;
+
+	default:
+		break;
+	}
+	spin_unlock_irqrestore(&soft->is_ir_lock, flag);
+	return intrs;
+}
+
+/**
+ * port_init - Initialize the sio and ioc4 hardware for a given port
+ *			called per port from attach...
+ * @port: port to initialize
+ */
+static int inline port_init(struct ioc4_port *port)
+{
+	uint32_t sio_cr;
+	struct hooks *hooks = port->ip_hooks;
+	struct ioc4_uartregs __iomem *uart;
+
+	/* Idle the IOC4 serial interface */
+	writel(IOC4_SSCR_RESET, &port->ip_serial_regs->sscr);
+
+	/* Wait until any pending bus activity for this port has ceased */
+	do
+		sio_cr = readl(&port->ip_mem->sio_cr.raw);
+	while (!(sio_cr & IOC4_SIO_CR_SIO_DIAG_IDLE));
+
+	/* Finish reset sequence */
+	writel(0, &port->ip_serial_regs->sscr);
+
+	/* Once RESET is done, reload cached tx_prod and rx_cons values
+	 * and set rings to empty by making prod == cons
+	 */
+	port->ip_tx_prod = readl(&port->ip_serial_regs->stcir) & PROD_CONS_MASK;
+	writel(port->ip_tx_prod, &port->ip_serial_regs->stpir);
+	port->ip_rx_cons = readl(&port->ip_serial_regs->srpir) & PROD_CONS_MASK;
+	writel(port->ip_rx_cons | IOC4_SRCIR_ARM, &port->ip_serial_regs->srcir);
+
+	/* Disable interrupts for this 16550 */
+	uart = port->ip_uart_regs;
+	writeb(0, &uart->i4u_lcr);
+	writeb(0, &uart->i4u_ier);
+
+	/* Set the default baud */
+	set_baud(port, port->ip_baud);
+
+	/* Set line control to 8 bits no parity */
+	writeb(UART_LCR_WLEN8 | 0, &uart->i4u_lcr);
+					/* UART_LCR_STOP == 1 stop */
+
+	/* Enable the FIFOs */
+	writeb(UART_FCR_ENABLE_FIFO, &uart->i4u_fcr);
+	/* then reset 16550 FIFOs */
+	writeb(UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
+			&uart->i4u_fcr);
+
+	/* Clear modem control register */
+	writeb(0, &uart->i4u_mcr);
+
+	/* Clear deltas in modem status register */
+	readb(&uart->i4u_msr);
+
+	/* Only do this once per port pair */
+	if (port->ip_hooks == &hooks_array[0]
+			    || port->ip_hooks == &hooks_array[2]) {
+		unsigned long ring_pci_addr;
+		uint32_t __iomem *sbbr_l;
+		uint32_t __iomem *sbbr_h;
+
+		if (port->ip_hooks == &hooks_array[0]) {
+			sbbr_l = &port->ip_serial->sbbr01_l;
+			sbbr_h = &port->ip_serial->sbbr01_h;
+		} else {
+			sbbr_l = &port->ip_serial->sbbr23_l;
+			sbbr_h = &port->ip_serial->sbbr23_h;
+		}
+
+		ring_pci_addr = (unsigned long __iomem)port->ip_dma_ringbuf;
+		DPRINT_CONFIG(("%s: ring_pci_addr 0x%lx\n",
+					__func__, ring_pci_addr));
+
+		writel((unsigned int)((uint64_t)ring_pci_addr >> 32), sbbr_h);
+		writel((unsigned int)ring_pci_addr | IOC4_BUF_SIZE_BIT, sbbr_l);
+	}
+
+	/* Set the receive timeout value to 10 msec */
+	writel(IOC4_SRTR_HZ / 100, &port->ip_serial_regs->srtr);
+
+	/* Set rx threshold, enable DMA */
+	/* Set high water mark at 3/4 of full ring */
+	port->ip_sscr = (ENTRIES_PER_RING * 3 / 4);
+	writel(port->ip_sscr, &port->ip_serial_regs->sscr);
+
+	/* Disable and clear all serial related interrupt bits */
+	write_ireg(port->ip_ioc4_soft, hooks->intr_clear,
+		       IOC4_W_IEC, IOC4_SIO_INTR_TYPE);
+	port->ip_ienb &= ~hooks->intr_clear;
+	writel(hooks->intr_clear, &port->ip_mem->sio_ir.raw);
+	return 0;
+}
+
+/**
+ * handle_dma_error_intr - service any pending DMA error interrupts for the
+ *			given port - 2nd level called via sd_intr
+ * @arg: handler arg
+ * @other_ir: ioc4regs
+ */
+static void handle_dma_error_intr(void *arg, uint32_t other_ir)
+{
+	struct ioc4_port *port = (struct ioc4_port *)arg;
+	struct hooks *hooks = port->ip_hooks;
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->ip_lock, flags);
+
+	/* ACK the interrupt */
+	writel(hooks->intr_dma_error, &port->ip_mem->other_ir.raw);
+
+	if (readl(&port->ip_mem->pci_err_addr_l.raw) & IOC4_PCI_ERR_ADDR_VLD) {
+		printk(KERN_ERR
+			"PCI error address is 0x%llx, "
+				"master is serial port %c %s\n",
+		     (((uint64_t)readl(&port->ip_mem->pci_err_addr_h)
+							 << 32)
+				| readl(&port->ip_mem->pci_err_addr_l.raw))
+					& IOC4_PCI_ERR_ADDR_ADDR_MSK, '1' +
+		     ((char)(readl(&port->ip_mem->pci_err_addr_l.raw) &
+			     IOC4_PCI_ERR_ADDR_MST_NUM_MSK) >> 1),
+		     (readl(&port->ip_mem->pci_err_addr_l.raw)
+				& IOC4_PCI_ERR_ADDR_MST_TYP_MSK)
+				? "RX" : "TX");
+
+		if (readl(&port->ip_mem->pci_err_addr_l.raw)
+						& IOC4_PCI_ERR_ADDR_MUL_ERR) {
+			printk(KERN_ERR
+				"Multiple errors occurred\n");
+		}
+	}
+	spin_unlock_irqrestore(&port->ip_lock, flags);
+
+	/* Re-enable DMA error interrupts */
+	write_ireg(port->ip_ioc4_soft, hooks->intr_dma_error, IOC4_W_IES,
+						IOC4_OTHER_INTR_TYPE);
+}
+
+/**
+ * intr_connect - interrupt connect function
+ * @soft: soft struct for this card
+ * @type: interrupt type
+ * @intrbits: bit pattern to set
+ * @intr: handler function
+ * @info: handler arg
+ */
+static void
+intr_connect(struct ioc4_soft *soft, int type,
+		  uint32_t intrbits, ioc4_intr_func_f * intr, void *info)
+{
+	int i;
+	struct ioc4_intr_info *intr_ptr;
+
+	BUG_ON(!((type == IOC4_SIO_INTR_TYPE)
+	       || (type == IOC4_OTHER_INTR_TYPE)));
+
+	i = atomic_inc_return(&soft-> is_intr_type[type].is_num_intrs) - 1;
+	BUG_ON(!(i < MAX_IOC4_INTR_ENTS || (printk("i %d\n", i), 0)));
+
+	/* Save off the lower level interrupt handler */
+	intr_ptr = &soft->is_intr_type[type].is_intr_info[i];
+	intr_ptr->sd_bits = intrbits;
+	intr_ptr->sd_intr = intr;
+	intr_ptr->sd_info = info;
+}
+
+/**
+ * ioc4_intr - Top level IOC4 interrupt handler.
+ * @irq: irq value
+ * @arg: handler arg
+ */
+
+static irqreturn_t ioc4_intr(int irq, void *arg)
+{
+	struct ioc4_soft *soft;
+	uint32_t this_ir, this_mir;
+	int xx, num_intrs = 0;
+	int intr_type;
+	int handled = 0;
+	struct ioc4_intr_info *intr_info;
+
+	soft = arg;
+	for (intr_type = 0; intr_type < IOC4_NUM_INTR_TYPES; intr_type++) {
+		num_intrs = (int)atomic_read(
+				&soft->is_intr_type[intr_type].is_num_intrs);
+
+		this_mir = this_ir = pending_intrs(soft, intr_type);
+
+		/* Farm out the interrupt to the various drivers depending on
+		 * which interrupt bits are set.
+		 */
+		for (xx = 0; xx < num_intrs; xx++) {
+			intr_info = &soft->is_intr_type[intr_type].is_intr_info[xx];
+			if ((this_mir = this_ir & intr_info->sd_bits)) {
+				/* Disable owned interrupts, call handler */
+				handled++;
+				write_ireg(soft, intr_info->sd_bits, IOC4_W_IEC,
+								intr_type);
+				intr_info->sd_intr(intr_info->sd_info, this_mir);
+				this_ir &= ~this_mir;
+			}
+		}
+	}
+#ifdef DEBUG_INTERRUPTS
+	{
+		struct ioc4_misc_regs __iomem *mem = soft->is_ioc4_misc_addr;
+		unsigned long flag;
+
+		spin_lock_irqsave(&soft->is_ir_lock, flag);
+		printk ("%s : %d : mem 0x%p sio_ir 0x%x sio_ies 0x%x "
+				"other_ir 0x%x other_ies 0x%x mask 0x%x\n",
+		     __func__, __LINE__,
+		     (void *)mem, readl(&mem->sio_ir.raw),
+		     readl(&mem->sio_ies.raw),
+		     readl(&mem->other_ir.raw),
+		     readl(&mem->other_ies.raw),
+		     IOC4_OTHER_IR_ATA_INT | IOC4_OTHER_IR_ATA_MEMERR);
+		spin_unlock_irqrestore(&soft->is_ir_lock, flag);
+	}
+#endif
+	return handled ? IRQ_HANDLED : IRQ_NONE;
+}
+
+/**
+ * ioc4_attach_local - Device initialization.
+ *			Called at *_attach() time for each
+ *			IOC4 with serial ports in the system.
+ * @idd: Master module data for this IOC4
+ */
+static int inline ioc4_attach_local(struct ioc4_driver_data *idd)
+{
+	struct ioc4_port *port;
+	struct ioc4_port *ports[IOC4_NUM_SERIAL_PORTS];
+	int port_number;
+	uint16_t ioc4_revid_min = 62;
+	uint16_t ioc4_revid;
+	struct pci_dev *pdev = idd->idd_pdev;
+	struct ioc4_control* control = idd->idd_serial_data;
+	struct ioc4_soft *soft = control->ic_soft;
+	void __iomem *ioc4_misc = idd->idd_misc_regs;
+	void __iomem *ioc4_serial = soft->is_ioc4_serial_addr;
+
+	/* IOC4 firmware must be at least rev 62 */
+	pci_read_config_word(pdev, PCI_COMMAND_SPECIAL, &ioc4_revid);
+
+	printk(KERN_INFO "IOC4 firmware revision %d\n", ioc4_revid);
+	if (ioc4_revid < ioc4_revid_min) {
+		printk(KERN_WARNING
+		    "IOC4 serial not supported on firmware rev %d, "
+				"please upgrade to rev %d or higher\n",
+				ioc4_revid, ioc4_revid_min);
+		return -EPERM;
+	}
+	BUG_ON(ioc4_misc == NULL);
+	BUG_ON(ioc4_serial == NULL);
+
+	/* Create port structures for each port */
+	for (port_number = 0; port_number < IOC4_NUM_SERIAL_PORTS;
+							port_number++) {
+		port = kzalloc(sizeof(struct ioc4_port), GFP_KERNEL);
+		if (!port) {
+			printk(KERN_WARNING
+				"IOC4 serial memory not available for port\n");
+			return -ENOMEM;
+		}
+		spin_lock_init(&port->ip_lock);
+
+		/* we need to remember the previous ones, to point back to
+		 * them farther down - setting up the ring buffers.
+		 */
+		ports[port_number] = port;
+
+		/* Allocate buffers and jumpstart the hardware.  */
+		control->ic_port[port_number].icp_port = port;
+		port->ip_ioc4_soft = soft;
+		port->ip_pdev = pdev;
+		port->ip_ienb = 0;
+		/* Use baud rate calculations based on detected PCI
+		 * bus speed.  Simply test whether the PCI clock is
+		 * running closer to 66MHz or 33MHz.
+		 */
+		if (idd->count_period/IOC4_EXTINT_COUNT_DIVISOR < 20) {
+			port->ip_pci_bus_speed = IOC4_SER_XIN_CLK_66;
+		} else {
+			port->ip_pci_bus_speed = IOC4_SER_XIN_CLK_33;
+		}
+		port->ip_baud = 9600;
+		port->ip_control = control;
+		port->ip_mem = ioc4_misc;
+		port->ip_serial = ioc4_serial;
+
+		/* point to the right hook */
+		port->ip_hooks = &hooks_array[port_number];
+
+		/* Get direct hooks to the serial regs and uart regs
+		 * for this port
+		 */
+		switch (port_number) {
+		case 0:
+			port->ip_serial_regs = &(port->ip_serial->port_0);
+			port->ip_uart_regs = &(port->ip_serial->uart_0);
+			break;
+		case 1:
+			port->ip_serial_regs = &(port->ip_serial->port_1);
+			port->ip_uart_regs = &(port->ip_serial->uart_1);
+			break;
+		case 2:
+			port->ip_serial_regs = &(port->ip_serial->port_2);
+			port->ip_uart_regs = &(port->ip_serial->uart_2);
+			break;
+		default:
+		case 3:
+			port->ip_serial_regs = &(port->ip_serial->port_3);
+			port->ip_uart_regs = &(port->ip_serial->uart_3);
+			break;
+		}
+
+		/* ring buffers are 1 to a pair of ports */
+		if (port_number && (port_number & 1)) {
+			/* odd use the evens buffer */
+			port->ip_dma_ringbuf =
+					ports[port_number - 1]->ip_dma_ringbuf;
+			port->ip_cpu_ringbuf =
+					ports[port_number - 1]->ip_cpu_ringbuf;
+			port->ip_inring = RING(port, RX_1_OR_3);
+			port->ip_outring = RING(port, TX_1_OR_3);
+
+		} else {
+			if (port->ip_dma_ringbuf == 0) {
+				port->ip_cpu_ringbuf = pci_alloc_consistent
+					(pdev, TOTAL_RING_BUF_SIZE,
+					&port->ip_dma_ringbuf);
+
+			}
+			BUG_ON(!((((int64_t)port->ip_dma_ringbuf) &
+				(TOTAL_RING_BUF_SIZE - 1)) == 0));
+			DPRINT_CONFIG(("%s : ip_cpu_ringbuf 0x%p "
+						"ip_dma_ringbuf 0x%p\n",
+					__func__,
+					(void *)port->ip_cpu_ringbuf,
+					(void *)port->ip_dma_ringbuf));
+			port->ip_inring = RING(port, RX_0_OR_2);
+			port->ip_outring = RING(port, TX_0_OR_2);
+		}
+		DPRINT_CONFIG(("%s : port %d [addr 0x%p] control 0x%p",
+				__func__,
+				port_number, (void *)port, (void *)control));
+		DPRINT_CONFIG((" ip_serial_regs 0x%p ip_uart_regs 0x%p\n",
+				(void *)port->ip_serial_regs,
+				(void *)port->ip_uart_regs));
+
+		/* Initialize the hardware for IOC4 */
+		port_init(port);
+
+		DPRINT_CONFIG(("%s: port_number %d port 0x%p inring 0x%p "
+						"outring 0x%p\n",
+				__func__,
+				port_number, (void *)port,
+				(void *)port->ip_inring,
+				(void *)port->ip_outring));
+
+		/* Attach interrupt handlers */
+		intr_connect(soft, IOC4_SIO_INTR_TYPE,
+				GET_SIO_IR(port_number),
+				handle_intr, port);
+
+		intr_connect(soft, IOC4_OTHER_INTR_TYPE,
+				GET_OTHER_IR(port_number),
+				handle_dma_error_intr, port);
+	}
+	return 0;
+}
+
+/**
+ * enable_intrs - enable interrupts
+ * @port: port to enable
+ * @mask: mask to use
+ */
+static void enable_intrs(struct ioc4_port *port, uint32_t mask)
+{
+	struct hooks *hooks = port->ip_hooks;
+
+	if ((port->ip_ienb & mask) != mask) {
+		write_ireg(port->ip_ioc4_soft, mask, IOC4_W_IES,
+						IOC4_SIO_INTR_TYPE);
+		port->ip_ienb |= mask;
+	}
+
+	if (port->ip_ienb)
+		write_ireg(port->ip_ioc4_soft, hooks->intr_dma_error,
+				IOC4_W_IES, IOC4_OTHER_INTR_TYPE);
+}
+
+/**
+ * local_open - local open a port
+ * @port: port to open
+ */
+static inline int local_open(struct ioc4_port *port)
+{
+	int spiniter = 0;
+
+	port->ip_flags = PORT_ACTIVE;
+
+	/* Pause the DMA interface if necessary */
+	if (port->ip_sscr & IOC4_SSCR_DMA_EN) {
+		writel(port->ip_sscr | IOC4_SSCR_DMA_PAUSE,
+			&port->ip_serial_regs->sscr);
+		while((readl(&port->ip_serial_regs-> sscr)
+				& IOC4_SSCR_PAUSE_STATE) == 0) {
+			spiniter++;
+			if (spiniter > MAXITER) {
+				port->ip_flags = PORT_INACTIVE;
+				return -1;
+			}
+		}
+	}
+
+	/* Reset the input fifo.  If the uart received chars while the port
+	 * was closed and DMA is not enabled, the uart may have a bunch of
+	 * chars hanging around in its rx fifo which will not be discarded
+	 * by rclr in the upper layer. We must get rid of them here.
+	 */
+	writeb(UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR,
+				&port->ip_uart_regs->i4u_fcr);
+
+	writeb(UART_LCR_WLEN8, &port->ip_uart_regs->i4u_lcr);
+					/* UART_LCR_STOP == 1 stop */
+
+	/* Re-enable DMA, set default threshold to intr whenever there is
+	 * data available.
+	 */
+	port->ip_sscr &= ~IOC4_SSCR_RX_THRESHOLD;
+	port->ip_sscr |= 1;	/* default threshold */
+
+	/* Plug in the new sscr.  This implicitly clears the DMA_PAUSE
+	 * flag if it was set above
+	 */
+	writel(port->ip_sscr, &port->ip_serial_regs->sscr);
+	port->ip_tx_lowat = 1;
+	return 0;
+}
+
+/**
+ * set_rx_timeout - Set rx timeout and threshold values.
+ * @port: port to use
+ * @timeout: timeout value in ticks
+ */
+static inline int set_rx_timeout(struct ioc4_port *port, int timeout)
+{
+	int threshold;
+
+	port->ip_rx_timeout = timeout;
+
+	/* Timeout is in ticks.  Let's figure out how many chars we
+	 * can receive at the current baud rate in that interval
+	 * and set the rx threshold to that amount.  There are 4 chars
+	 * per ring entry, so we'll divide the number of chars that will
+	 * arrive in timeout by 4.
+	 * So .... timeout * baud / 10 / HZ / 4, with HZ = 100.
+	 */
+	threshold = timeout * port->ip_baud / 4000;
+	if (threshold == 0)
+		threshold = 1;	/* otherwise we'll intr all the time! */
+
+	if ((unsigned)threshold > (unsigned)IOC4_SSCR_RX_THRESHOLD)
+		return 1;
+
+	port->ip_sscr &= ~IOC4_SSCR_RX_THRESHOLD;
+	port->ip_sscr |= threshold;
+
+	writel(port->ip_sscr, &port->ip_serial_regs->sscr);
+
+	/* Now set the rx timeout to the given value
+	 * again timeout * IOC4_SRTR_HZ / HZ
+	 */
+	timeout = timeout * IOC4_SRTR_HZ / 100;
+	if (timeout > IOC4_SRTR_CNT)
+		timeout = IOC4_SRTR_CNT;
+
+	writel(timeout, &port->ip_serial_regs->srtr);
+	return 0;
+}
+
+/**
+ * config_port - config the hardware
+ * @port: port to config
+ * @baud: baud rate for the port
+ * @byte_size: data size
+ * @stop_bits: number of stop bits
+ * @parenb: parity enable ?
+ * @parodd: odd parity ?
+ */
+static inline int
+config_port(struct ioc4_port *port,
+	    int baud, int byte_size, int stop_bits, int parenb, int parodd)
+{
+	char lcr, sizebits;
+	int spiniter = 0;
+
+	DPRINT_CONFIG(("%s: baud %d byte_size %d stop %d parenb %d parodd %d\n",
+		__func__, baud, byte_size, stop_bits, parenb, parodd));
+
+	if (set_baud(port, baud))
+		return 1;
+
+	switch (byte_size) {
+	case 5:
+		sizebits = UART_LCR_WLEN5;
+		break;
+	case 6:
+		sizebits = UART_LCR_WLEN6;
+		break;
+	case 7:
+		sizebits = UART_LCR_WLEN7;
+		break;
+	case 8:
+		sizebits = UART_LCR_WLEN8;
+		break;
+	default:
+		return 1;
+	}
+
+	/* Pause the DMA interface if necessary */
+	if (port->ip_sscr & IOC4_SSCR_DMA_EN) {
+		writel(port->ip_sscr | IOC4_SSCR_DMA_PAUSE,
+			&port->ip_serial_regs->sscr);
+		while((readl(&port->ip_serial_regs->sscr)
+						& IOC4_SSCR_PAUSE_STATE) == 0) {
+			spiniter++;
+			if (spiniter > MAXITER)
+				return -1;
+		}
+	}
+
+	/* Clear relevant fields in lcr */
+	lcr = readb(&port->ip_uart_regs->i4u_lcr);
+	lcr &= ~(LCR_MASK_BITS_CHAR | UART_LCR_EPAR |
+		 UART_LCR_PARITY | LCR_MASK_STOP_BITS);
+
+	/* Set byte size in lcr */
+	lcr |= sizebits;
+
+	/* Set parity */
+	if (parenb) {
+		lcr |= UART_LCR_PARITY;
+		if (!parodd)
+			lcr |= UART_LCR_EPAR;
+	}
+
+	/* Set stop bits */
+	if (stop_bits)
+		lcr |= UART_LCR_STOP /* 2 stop bits */ ;
+
+	writeb(lcr, &port->ip_uart_regs->i4u_lcr);
+
+	/* Re-enable the DMA interface if necessary */
+	if (port->ip_sscr & IOC4_SSCR_DMA_EN) {
+		writel(port->ip_sscr, &port->ip_serial_regs->sscr);
+	}
+	port->ip_baud = baud;
+
+	/* When we get within this number of ring entries of filling the
+	 * entire ring on tx, place an EXPLICIT intr to generate a lowat
+	 * notification when output has drained.
+	 */
+	port->ip_tx_lowat = (TX_LOWAT_CHARS(baud) + 3) / 4;
+	if (port->ip_tx_lowat == 0)
+		port->ip_tx_lowat = 1;
+
+	set_rx_timeout(port, 2);
+
+	return 0;
+}
+
+/**
+ * do_write - Write bytes to the port.  Returns the number of bytes
+ *			actually written. Called from transmit_chars
+ * @port: port to use
+ * @buf: the stuff to write
+ * @len: how many bytes in 'buf'
+ */
+static inline int do_write(struct ioc4_port *port, char *buf, int len)
+{
+	int prod_ptr, cons_ptr, total = 0;
+	struct ring *outring;
+	struct ring_entry *entry;
+	struct hooks *hooks = port->ip_hooks;
+
+	BUG_ON(!(len >= 0));
+
+	prod_ptr = port->ip_tx_prod;
+	cons_ptr = readl(&port->ip_serial_regs->stcir) & PROD_CONS_MASK;
+	outring = port->ip_outring;
+
+	/* Maintain a 1-entry red-zone.  The ring buffer is full when
+	 * (cons - prod) % ring_size is 1.  Rather than do this subtraction
+	 * in the body of the loop, I'll do it now.
+	 */
+	cons_ptr = (cons_ptr - (int)sizeof(struct ring_entry)) & PROD_CONS_MASK;
+
+	/* Stuff the bytes into the output */
+	while ((prod_ptr != cons_ptr) && (len > 0)) {
+		int xx;
+
+		/* Get 4 bytes (one ring entry) at a time */
+		entry = (struct ring_entry *)((caddr_t) outring + prod_ptr);
+
+		/* Invalidate all entries */
+		entry->ring_allsc = 0;
+
+		/* Copy in some bytes */
+		for (xx = 0; (xx < 4) && (len > 0); xx++) {
+			entry->ring_data[xx] = *buf++;
+			entry->ring_sc[xx] = IOC4_TXCB_VALID;
+			len--;
+			total++;
+		}
+
+		/* If we are within some small threshold of filling up the
+		 * entire ring buffer, we must place an EXPLICIT intr here
+		 * to generate a lowat interrupt in case we subsequently
+		 * really do fill up the ring and the caller goes to sleep.
+		 * No need to place more than one though.
+		 */
+		if (!(port->ip_flags & LOWAT_WRITTEN) &&
+			((cons_ptr - prod_ptr) & PROD_CONS_MASK)
+				<= port->ip_tx_lowat
+					* (int)sizeof(struct ring_entry)) {
+			port->ip_flags |= LOWAT_WRITTEN;
+			entry->ring_sc[0] |= IOC4_TXCB_INT_WHEN_DONE;
+		}
+
+		/* Go on to next entry */
+		prod_ptr += sizeof(struct ring_entry);
+		prod_ptr &= PROD_CONS_MASK;
+	}
+
+	/* If we sent something, start DMA if necessary */
+	if (total > 0 && !(port->ip_sscr & IOC4_SSCR_DMA_EN)) {
+		port->ip_sscr |= IOC4_SSCR_DMA_EN;
+		writel(port->ip_sscr, &port->ip_serial_regs->sscr);
+	}
+
+	/* Store the new producer pointer.  If tx is disabled, we stuff the
+	 * data into the ring buffer, but we don't actually start tx.
+	 */
+	if (!uart_tx_stopped(port->ip_port)) {
+		writel(prod_ptr, &port->ip_serial_regs->stpir);
+
+		/* If we are now transmitting, enable tx_mt interrupt so we
+		 * can disable DMA if necessary when the tx finishes.
+		 */
+		if (total > 0)
+			enable_intrs(port, hooks->intr_tx_mt);
+	}
+	port->ip_tx_prod = prod_ptr;
+	return total;
+}
+
+/**
+ * disable_intrs - disable interrupts
+ * @port: port to enable
+ * @mask: mask to use
+ */
+static void disable_intrs(struct ioc4_port *port, uint32_t mask)
+{
+	struct hooks *hooks = port->ip_hooks;
+
+	if (port->ip_ienb & mask) {
+		write_ireg(port->ip_ioc4_soft, mask, IOC4_W_IEC,
+					IOC4_SIO_INTR_TYPE);
+		port->ip_ienb &= ~mask;
+	}
+
+	if (!port->ip_ienb)
+		write_ireg(port->ip_ioc4_soft, hooks->intr_dma_error,
+				IOC4_W_IEC, IOC4_OTHER_INTR_TYPE);
+}
+
+/**
+ * set_notification - Modify event notification
+ * @port: port to use
+ * @mask: events mask
+ * @set_on: set ?
+ */
+static int set_notification(struct ioc4_port *port, int mask, int set_on)
+{
+	struct hooks *hooks = port->ip_hooks;
+	uint32_t intrbits, sscrbits;
+
+	BUG_ON(!mask);
+
+	intrbits = sscrbits = 0;
+
+	if (mask & N_DATA_READY)
+		intrbits |= (hooks->intr_rx_timer | hooks->intr_rx_high);
+	if (mask & N_OUTPUT_LOWAT)
+		intrbits |= hooks->intr_tx_explicit;
+	if (mask & N_DDCD) {
+		intrbits |= hooks->intr_delta_dcd;
+		sscrbits |= IOC4_SSCR_RX_RING_DCD;
+	}
+	if (mask & N_DCTS)
+		intrbits |= hooks->intr_delta_cts;
+
+	if (set_on) {
+		enable_intrs(port, intrbits);
+		port->ip_notify |= mask;
+		port->ip_sscr |= sscrbits;
+	} else {
+		disable_intrs(port, intrbits);
+		port->ip_notify &= ~mask;
+		port->ip_sscr &= ~sscrbits;
+	}
+
+	/* We require DMA if either DATA_READY or DDCD notification is
+	 * currently requested. If neither of these is requested and
+	 * there is currently no tx in progress, DMA may be disabled.
+	 */
+	if (port->ip_notify & (N_DATA_READY | N_DDCD))
+		port->ip_sscr |= IOC4_SSCR_DMA_EN;
+	else if (!(port->ip_ienb & hooks->intr_tx_mt))
+		port->ip_sscr &= ~IOC4_SSCR_DMA_EN;
+
+	writel(port->ip_sscr, &port->ip_serial_regs->sscr);
+	return 0;
+}
+
+/**
+ * set_mcr - set the master control reg
+ * @the_port: port to use
+ * @mask1: mcr mask
+ * @mask2: shadow mask
+ */
+static inline int set_mcr(struct uart_port *the_port,
+		int mask1, int mask2)
+{
+	struct ioc4_port *port = get_ioc4_port(the_port, 0);
+	uint32_t shadow;
+	int spiniter = 0;
+	char mcr;
+
+	if (!port)
+		return -1;
+
+	/* Pause the DMA interface if necessary */
+	if (port->ip_sscr & IOC4_SSCR_DMA_EN) {
+		writel(port->ip_sscr | IOC4_SSCR_DMA_PAUSE,
+			&port->ip_serial_regs->sscr);
+		while ((readl(&port->ip_serial_regs->sscr)
+					& IOC4_SSCR_PAUSE_STATE) == 0) {
+			spiniter++;
+			if (spiniter > MAXITER)
+				return -1;
+		}
+	}
+	shadow = readl(&port->ip_serial_regs->shadow);
+	mcr = (shadow & 0xff000000) >> 24;
+
+	/* Set new value */
+	mcr |= mask1;
+	shadow |= mask2;
+
+	writeb(mcr, &port->ip_uart_regs->i4u_mcr);
+	writel(shadow, &port->ip_serial_regs->shadow);
+
+	/* Re-enable the DMA interface if necessary */
+	if (port->ip_sscr & IOC4_SSCR_DMA_EN) {
+		writel(port->ip_sscr, &port->ip_serial_regs->sscr);
+	}
+	return 0;
+}
+
+/**
+ * ioc4_set_proto - set the protocol for the port
+ * @port: port to use
+ * @proto: protocol to use
+ */
+static int ioc4_set_proto(struct ioc4_port *port, int proto)
+{
+	struct hooks *hooks = port->ip_hooks;
+
+	switch (proto) {
+	case PROTO_RS232:
+		/* Clear the appropriate GIO pin */
+		writel(0, (&port->ip_mem->gppr[hooks->rs422_select_pin].raw));
+		break;
+
+	case PROTO_RS422:
+		/* Set the appropriate GIO pin */
+		writel(1, (&port->ip_mem->gppr[hooks->rs422_select_pin].raw));
+		break;
+
+	default:
+		return 1;
+	}
+	return 0;
+}
+
+/**
+ * transmit_chars - upper level write, called with ip_lock
+ * @the_port: port to write
+ */
+static void transmit_chars(struct uart_port *the_port)
+{
+	int xmit_count, tail, head;
+	int result;
+	char *start;
+	struct tty_struct *tty;
+	struct ioc4_port *port = get_ioc4_port(the_port, 0);
+	struct uart_state *state;
+
+	if (!the_port)
+		return;
+	if (!port)
+		return;
+
+	state = the_port->state;
+	tty = state->port.tty;
+
+	if (uart_circ_empty(&state->xmit) || uart_tx_stopped(the_port)) {
+		/* Nothing to do or hw stopped */
+		set_notification(port, N_ALL_OUTPUT, 0);
+		return;
+	}
+
+	head = state->xmit.head;
+	tail = state->xmit.tail;
+	start = (char *)&state->xmit.buf[tail];
+
+	/* write out all the data or until the end of the buffer */
+	xmit_count = (head < tail) ? (UART_XMIT_SIZE - tail) : (head - tail);
+	if (xmit_count > 0) {
+		result = do_write(port, start, xmit_count);
+		if (result > 0) {
+			/* booking */
+			xmit_count -= result;
+			the_port->icount.tx += result;
+			/* advance the pointers */
+			tail += result;
+			tail &= UART_XMIT_SIZE - 1;
+			state->xmit.tail = tail;
+			start = (char *)&state->xmit.buf[tail];
+		}
+	}
+	if (uart_circ_chars_pending(&state->xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(the_port);
+
+	if (uart_circ_empty(&state->xmit)) {
+		set_notification(port, N_OUTPUT_LOWAT, 0);
+	} else {
+		set_notification(port, N_OUTPUT_LOWAT, 1);
+	}
+}
+
+/**
+ * ioc4_change_speed - change the speed of the port
+ * @the_port: port to change
+ * @new_termios: new termios settings
+ * @old_termios: old termios settings
+ */
+static void
+ioc4_change_speed(struct uart_port *the_port,
+		  struct ktermios *new_termios, struct ktermios *old_termios)
+{
+	struct ioc4_port *port = get_ioc4_port(the_port, 0);
+	int baud, bits;
+	unsigned cflag, iflag;
+	int new_parity = 0, new_parity_enable = 0, new_stop = 0, new_data = 8;
+	struct uart_state *state = the_port->state;
+
+	cflag = new_termios->c_cflag;
+	iflag = new_termios->c_iflag;
+
+	switch (cflag & CSIZE) {
+	case CS5:
+		new_data = 5;
+		bits = 7;
+		break;
+	case CS6:
+		new_data = 6;
+		bits = 8;
+		break;
+	case CS7:
+		new_data = 7;
+		bits = 9;
+		break;
+	case CS8:
+		new_data = 8;
+		bits = 10;
+		break;
+	default:
+		/* cuz we always need a default ... */
+		new_data = 5;
+		bits = 7;
+		break;
+	}
+	if (cflag & CSTOPB) {
+		bits++;
+		new_stop = 1;
+	}
+	if (cflag & PARENB) {
+		bits++;
+		new_parity_enable = 1;
+		if (cflag & PARODD)
+			new_parity = 1;
+	}
+	baud = uart_get_baud_rate(the_port, new_termios, old_termios,
+				MIN_BAUD_SUPPORTED, MAX_BAUD_SUPPORTED);
+	DPRINT_CONFIG(("%s: returned baud %d\n", __func__, baud));
+
+	/* default is 9600 */
+	if (!baud)
+		baud = 9600;
+
+	if (!the_port->fifosize)
+		the_port->fifosize = IOC4_FIFO_CHARS;
+	the_port->timeout = ((the_port->fifosize * HZ * bits) / (baud / 10));
+	the_port->timeout += HZ / 50;	/* Add .02 seconds of slop */
+
+	the_port->ignore_status_mask = N_ALL_INPUT;
+
+	state->port.low_latency = 1;
+
+	if (iflag & IGNPAR)
+		the_port->ignore_status_mask &= ~(N_PARITY_ERROR
+						| N_FRAMING_ERROR);
+	if (iflag & IGNBRK) {
+		the_port->ignore_status_mask &= ~N_BREAK;
+		if (iflag & IGNPAR)
+			the_port->ignore_status_mask &= ~N_OVERRUN_ERROR;
+	}
+	if (!(cflag & CREAD)) {
+		/* ignore everything */
+		the_port->ignore_status_mask &= ~N_DATA_READY;
+	}
+
+	if (cflag & CRTSCTS) {
+		port->ip_sscr |= IOC4_SSCR_HFC_EN;
+	}
+	else {
+		port->ip_sscr &= ~IOC4_SSCR_HFC_EN;
+	}
+	writel(port->ip_sscr, &port->ip_serial_regs->sscr);
+
+	/* Set the configuration and proper notification call */
+	DPRINT_CONFIG(("%s : port 0x%p cflag 0%o "
+		"config_port(baud %d data %d stop %d p enable %d parity %d),"
+		" notification 0x%x\n",
+	     __func__, (void *)port, cflag, baud, new_data, new_stop,
+	     new_parity_enable, new_parity, the_port->ignore_status_mask));
+
+	if ((config_port(port, baud,		/* baud */
+			 new_data,		/* byte size */
+			 new_stop,		/* stop bits */
+			 new_parity_enable,	/* set parity */
+			 new_parity)) >= 0) {	/* parity 1==odd */
+		set_notification(port, the_port->ignore_status_mask, 1);
+	}
+}
+
+/**
+ * ic4_startup_local - Start up the serial port - returns >= 0 if no errors
+ * @the_port: Port to operate on
+ */
+static inline int ic4_startup_local(struct uart_port *the_port)
+{
+	struct ioc4_port *port;
+	struct uart_state *state;
+
+	if (!the_port)
+		return -1;
+
+	port = get_ioc4_port(the_port, 0);
+	if (!port)
+		return -1;
+
+	state = the_port->state;
+
+	local_open(port);
+
+	/* set the protocol - mapbase has the port type */
+	ioc4_set_proto(port, the_port->mapbase);
+
+	/* set the speed of the serial port */
+	ioc4_change_speed(the_port, &state->port.tty->termios,
+			  (struct ktermios *)0);
+
+	return 0;
+}
+
+/*
+ * ioc4_cb_output_lowat - called when the output low water mark is hit
+ * @the_port: port to output
+ */
+static void ioc4_cb_output_lowat(struct uart_port *the_port)
+{
+	unsigned long pflags;
+
+	/* ip_lock is set on the call here */
+	if (the_port) {
+		spin_lock_irqsave(&the_port->lock, pflags);
+		transmit_chars(the_port);
+		spin_unlock_irqrestore(&the_port->lock, pflags);
+	}
+}
+
+/**
+ * handle_intr - service any interrupts for the given port - 2nd level
+ *			called via sd_intr
+ * @arg: handler arg
+ * @sio_ir: ioc4regs
+ */
+static void handle_intr(void *arg, uint32_t sio_ir)
+{
+	struct ioc4_port *port = (struct ioc4_port *)arg;
+	struct hooks *hooks = port->ip_hooks;
+	unsigned int rx_high_rd_aborted = 0;
+	unsigned long flags;
+	struct uart_port *the_port;
+	int loop_counter;
+
+	/* Possible race condition here: The tx_mt interrupt bit may be
+	 * cleared without the intervention of the interrupt handler,
+	 * e.g. by a write.  If the top level interrupt handler reads a
+	 * tx_mt, then some other processor does a write, starting up
+	 * output, then we come in here, see the tx_mt and stop DMA, the
+	 * output started by the other processor will hang.  Thus we can
+	 * only rely on tx_mt being legitimate if it is read while the
+	 * port lock is held.  Therefore this bit must be ignored in the
+	 * passed in interrupt mask which was read by the top level
+	 * interrupt handler since the port lock was not held at the time
+	 * it was read.  We can only rely on this bit being accurate if it
+	 * is read while the port lock is held.  So we'll clear it for now,
+	 * and reload it later once we have the port lock.
+	 */
+	sio_ir &= ~(hooks->intr_tx_mt);
+
+	spin_lock_irqsave(&port->ip_lock, flags);
+
+	loop_counter = MAXITER;	/* to avoid hangs */
+
+	do {
+		uint32_t shadow;
+
+		if ( loop_counter-- <= 0 ) {
+			printk(KERN_WARNING "IOC4 serial: "
+					"possible hang condition/"
+					"port stuck on interrupt.\n");
+			break;
+		}
+
+		/* Handle a DCD change */
+		if (sio_ir & hooks->intr_delta_dcd) {
+			/* ACK the interrupt */
+			writel(hooks->intr_delta_dcd,
+				&port->ip_mem->sio_ir.raw);
+
+			shadow = readl(&port->ip_serial_regs->shadow);
+
+			if ((port->ip_notify & N_DDCD)
+					&& (shadow & IOC4_SHADOW_DCD)
+					&& (port->ip_port)) {
+				the_port = port->ip_port;
+				the_port->icount.dcd = 1;
+				wake_up_interruptible
+					    (&the_port->state->port.delta_msr_wait);
+			} else if ((port->ip_notify & N_DDCD)
+					&& !(shadow & IOC4_SHADOW_DCD)) {
+				/* Flag delta DCD/no DCD */
+				port->ip_flags |= DCD_ON;
+			}
+		}
+
+		/* Handle a CTS change */
+		if (sio_ir & hooks->intr_delta_cts) {
+			/* ACK the interrupt */
+			writel(hooks->intr_delta_cts,
+					&port->ip_mem->sio_ir.raw);
+
+			shadow = readl(&port->ip_serial_regs->shadow);
+
+			if ((port->ip_notify & N_DCTS)
+					&& (port->ip_port)) {
+				the_port = port->ip_port;
+				the_port->icount.cts =
+					(shadow & IOC4_SHADOW_CTS) ? 1 : 0;
+				wake_up_interruptible
+					(&the_port->state->port.delta_msr_wait);
+			}
+		}
+
+		/* rx timeout interrupt.  Must be some data available.  Put this
+		 * before the check for rx_high since servicing this condition
+		 * may cause that condition to clear.
+		 */
+		if (sio_ir & hooks->intr_rx_timer) {
+			/* ACK the interrupt */
+			writel(hooks->intr_rx_timer,
+				&port->ip_mem->sio_ir.raw);
+
+			if ((port->ip_notify & N_DATA_READY)
+					&& (port->ip_port)) {
+				/* ip_lock is set on call here */
+				receive_chars(port->ip_port);
+			}
+		}
+
+		/* rx high interrupt. Must be after rx_timer.  */
+		else if (sio_ir & hooks->intr_rx_high) {
+			/* Data available, notify upper layer */
+			if ((port->ip_notify & N_DATA_READY)
+						&& port->ip_port) {
+				/* ip_lock is set on call here */
+				receive_chars(port->ip_port);
+			}
+
+			/* We can't ACK this interrupt.  If receive_chars didn't
+			 * cause the condition to clear, we'll have to disable
+			 * the interrupt until the data is drained.
+			 * If the read was aborted, don't disable the interrupt
+			 * as this may cause us to hang indefinitely.  An
+			 * aborted read generally means that this interrupt
+			 * hasn't been delivered to the cpu yet anyway, even
+			 * though we see it as asserted when we read the sio_ir.
+			 */
+			if ((sio_ir = PENDING(port)) & hooks->intr_rx_high) {
+				if ((port->ip_flags & READ_ABORTED) == 0) {
+					port->ip_ienb &= ~hooks->intr_rx_high;
+					port->ip_flags |= INPUT_HIGH;
+				} else {
+					rx_high_rd_aborted++;
+				}
+			}
+		}
+
+		/* We got a low water interrupt: notify upper layer to
+		 * send more data.  Must come before tx_mt since servicing
+		 * this condition may cause that condition to clear.
+		 */
+		if (sio_ir & hooks->intr_tx_explicit) {
+			port->ip_flags &= ~LOWAT_WRITTEN;
+
+			/* ACK the interrupt */
+			writel(hooks->intr_tx_explicit,
+					&port->ip_mem->sio_ir.raw);
+
+			if (port->ip_notify & N_OUTPUT_LOWAT)
+				ioc4_cb_output_lowat(port->ip_port);
+		}
+
+		/* Handle tx_mt.  Must come after tx_explicit.  */
+		else if (sio_ir & hooks->intr_tx_mt) {
+			/* If we are expecting a lowat notification
+			 * and we get to this point it probably means that for
+			 * some reason the tx_explicit didn't work as expected
+			 * (that can legitimately happen if the output buffer is
+			 * filled up in just the right way).
+			 * So send the notification now.
+			 */
+			if (port->ip_notify & N_OUTPUT_LOWAT) {
+				ioc4_cb_output_lowat(port->ip_port);
+
+				/* We need to reload the sio_ir since the lowat
+				 * call may have caused another write to occur,
+				 * clearing the tx_mt condition.
+				 */
+				sio_ir = PENDING(port);
+			}
+
+			/* If the tx_mt condition still persists even after the
+			 * lowat call, we've got some work to do.
+			 */
+			if (sio_ir & hooks->intr_tx_mt) {
+
+				/* If we are not currently expecting DMA input,
+				 * and the transmitter has just gone idle,
+				 * there is no longer any reason for DMA, so
+				 * disable it.
+				 */
+				if (!(port->ip_notify
+						& (N_DATA_READY | N_DDCD))) {
+					BUG_ON(!(port->ip_sscr
+							& IOC4_SSCR_DMA_EN));
+					port->ip_sscr &= ~IOC4_SSCR_DMA_EN;
+					writel(port->ip_sscr,
+					   &port->ip_serial_regs->sscr);
+				}
+
+				/* Prevent infinite tx_mt interrupt */
+				port->ip_ienb &= ~hooks->intr_tx_mt;
+			}
+		}
+		sio_ir = PENDING(port);
+
+		/* if the read was aborted and only hooks->intr_rx_high,
+		 * clear hooks->intr_rx_high, so we do not loop forever.
+		 */
+
+		if (rx_high_rd_aborted && (sio_ir == hooks->intr_rx_high)) {
+			sio_ir &= ~hooks->intr_rx_high;
+		}
+	} while (sio_ir & hooks->intr_all);
+
+	spin_unlock_irqrestore(&port->ip_lock, flags);
+
+	/* Re-enable interrupts before returning from interrupt handler.
+	 * Getting interrupted here is okay.  It'll just v() our semaphore, and
+	 * we'll come through the loop again.
+	 */
+
+	write_ireg(port->ip_ioc4_soft, port->ip_ienb, IOC4_W_IES,
+							IOC4_SIO_INTR_TYPE);
+}
+
+/*
+ * ioc4_cb_post_ncs - called for some basic errors
+ * @port: port to use
+ * @ncs: event
+ */
+static void ioc4_cb_post_ncs(struct uart_port *the_port, int ncs)
+{
+	struct uart_icount *icount;
+
+	icount = &the_port->icount;
+
+	if (ncs & NCS_BREAK)
+		icount->brk++;
+	if (ncs & NCS_FRAMING)
+		icount->frame++;
+	if (ncs & NCS_OVERRUN)
+		icount->overrun++;
+	if (ncs & NCS_PARITY)
+		icount->parity++;
+}
+
+/**
+ * do_read - Read in bytes from the port.  Return the number of bytes
+ *			actually read.
+ * @the_port: port to use
+ * @buf: place to put the stuff we read
+ * @len: how big 'buf' is
+ */
+
+static inline int do_read(struct uart_port *the_port, unsigned char *buf,
+				int len)
+{
+	int prod_ptr, cons_ptr, total;
+	struct ioc4_port *port = get_ioc4_port(the_port, 0);
+	struct ring *inring;
+	struct ring_entry *entry;
+	struct hooks *hooks;
+	int byte_num;
+	char *sc;
+	int loop_counter;
+
+	BUG_ON(!(len >= 0));
+	BUG_ON(!port);
+	hooks = port->ip_hooks;
+
+	/* There is a nasty timing issue in the IOC4. When the rx_timer
+	 * expires or the rx_high condition arises, we take an interrupt.
+	 * At some point while servicing the interrupt, we read bytes from
+	 * the ring buffer and re-arm the rx_timer.  However the rx_timer is
+	 * not started until the first byte is received *after* it is armed,
+	 * and any bytes pending in the rx construction buffers are not drained
+	 * to memory until either there are 4 bytes available or the rx_timer
+	 * expires.  This leads to a potential situation where data is left
+	 * in the construction buffers forever - 1 to 3 bytes were received
+	 * after the interrupt was generated but before the rx_timer was
+	 * re-armed. At that point as long as no subsequent bytes are received
+	 * the timer will never be started and the bytes will remain in the
+	 * construction buffer forever.  The solution is to execute a DRAIN
+	 * command after rearming the timer.  This way any bytes received before
+	 * the DRAIN will be drained to memory, and any bytes received after
+	 * the DRAIN will start the TIMER and be drained when it expires.
+	 * Luckily, this only needs to be done when the DMA buffer is empty
+	 * since there is no requirement that this function return all
+	 * available data as long as it returns some.
+	 */
+	/* Re-arm the timer */
+	writel(port->ip_rx_cons | IOC4_SRCIR_ARM, &port->ip_serial_regs->srcir);
+
+	prod_ptr = readl(&port->ip_serial_regs->srpir) & PROD_CONS_MASK;
+	cons_ptr = port->ip_rx_cons;
+
+	if (prod_ptr == cons_ptr) {
+		int reset_dma = 0;
+
+		/* Input buffer appears empty, do a flush. */
+
+		/* DMA must be enabled for this to work. */
+		if (!(port->ip_sscr & IOC4_SSCR_DMA_EN)) {
+			port->ip_sscr |= IOC4_SSCR_DMA_EN;
+			reset_dma = 1;
+		}
+
+		/* Potential race condition: we must reload the srpir after
+		 * issuing the drain command, otherwise we could think the rx
+		 * buffer is empty, then take a very long interrupt, and when
+		 * we come back it's full and we wait forever for the drain to
+		 * complete.
+		 */
+		writel(port->ip_sscr | IOC4_SSCR_RX_DRAIN,
+				&port->ip_serial_regs->sscr);
+		prod_ptr = readl(&port->ip_serial_regs->srpir)
+				& PROD_CONS_MASK;
+
+		/* We must not wait for the DRAIN to complete unless there are
+		 * at least 8 bytes (2 ring entries) available to receive the
+		 * data otherwise the DRAIN will never complete and we'll
+		 * deadlock here.
+		 * In fact, to make things easier, I'll just ignore the flush if
+		 * there is any data at all now available.
+		 */
+		if (prod_ptr == cons_ptr) {
+			loop_counter = 0;
+			while (readl(&port->ip_serial_regs->sscr) &
+						IOC4_SSCR_RX_DRAIN) {
+				loop_counter++;
+				if (loop_counter > MAXITER)
+					return -1;
+			}
+
+			/* SIGH. We have to reload the prod_ptr *again* since
+			 * the drain may have caused it to change
+			 */
+			prod_ptr = readl(&port->ip_serial_regs->srpir)
+							& PROD_CONS_MASK;
+		}
+		if (reset_dma) {
+			port->ip_sscr &= ~IOC4_SSCR_DMA_EN;
+			writel(port->ip_sscr, &port->ip_serial_regs->sscr);
+		}
+	}
+	inring = port->ip_inring;
+	port->ip_flags &= ~READ_ABORTED;
+
+	total = 0;
+	loop_counter = 0xfffff;	/* to avoid hangs */
+
+	/* Grab bytes from the hardware */
+	while ((prod_ptr != cons_ptr) && (len > 0)) {
+		entry = (struct ring_entry *)((caddr_t)inring + cons_ptr);
+
+		if ( loop_counter-- <= 0 ) {
+			printk(KERN_WARNING "IOC4 serial: "
+					"possible hang condition/"
+					"port stuck on read.\n");
+			break;
+		}
+
+		/* According to the producer pointer, this ring entry
+		 * must contain some data.  But if the PIO happened faster
+		 * than the DMA, the data may not be available yet, so let's
+		 * wait until it arrives.
+		 */
+		if ((entry->ring_allsc & RING_ANY_VALID) == 0) {
+			/* Indicate the read is aborted so we don't disable
+			 * the interrupt thinking that the consumer is
+			 * congested.
+			 */
+			port->ip_flags |= READ_ABORTED;
+			len = 0;
+			break;
+		}
+
+		/* Load the bytes/status out of the ring entry */
+		for (byte_num = 0; byte_num < 4 && len > 0; byte_num++) {
+			sc = &(entry->ring_sc[byte_num]);
+
+			/* Check for change in modem state or overrun */
+			if ((*sc & IOC4_RXSB_MODEM_VALID)
+						&& (port->ip_notify & N_DDCD)) {
+				/* Notify upper layer if DCD dropped */
+
+				if ((port->ip_flags & DCD_ON)
+						&& !(*sc & IOC4_RXSB_DCD)) {
+
+					/* If we have already copied some data,
+					 * return it.  We'll pick up the carrier
+					 * drop on the next pass.  That way we
+					 * don't throw away the data that has
+					 * already been copied back to
+					 * the caller's buffer.
+					 */
+					if (total > 0) {
+						len = 0;
+						break;
+					}
+					port->ip_flags &= ~DCD_ON;
+
+					/* Turn off this notification so the
+					 * carrier drop protocol won't see it
+					 * again when it does a read.
+					 */
+					*sc &= ~IOC4_RXSB_MODEM_VALID;
+
+					/* To keep things consistent, we need
+					 * to update the consumer pointer so
+					 * the next reader won't come in and
+					 * try to read the same ring entries
+					 * again. This must be done here before
+					 * the dcd change.
+					 */
+
+					if ((entry->ring_allsc & RING_ANY_VALID)
+									== 0) {
+						cons_ptr += (int)sizeof
+							(struct ring_entry);
+						cons_ptr &= PROD_CONS_MASK;
+					}
+					writel(cons_ptr,
+						&port->ip_serial_regs->srcir);
+					port->ip_rx_cons = cons_ptr;
+
+					/* Notify upper layer of carrier drop */
+					if ((port->ip_notify & N_DDCD)
+						   && port->ip_port) {
+						the_port->icount.dcd = 0;
+						wake_up_interruptible
+						    (&the_port->state->
+							port.delta_msr_wait);
+					}
+
+					/* If we had any data to return, we
+					 * would have returned it above.
+					 */
+					return 0;
+				}
+			}
+			if (*sc & IOC4_RXSB_MODEM_VALID) {
+				/* Notify that an input overrun occurred */
+				if ((*sc & IOC4_RXSB_OVERRUN)
+				    && (port->ip_notify & N_OVERRUN_ERROR)) {
+					ioc4_cb_post_ncs(the_port, NCS_OVERRUN);
+				}
+				/* Don't look at this byte again */
+				*sc &= ~IOC4_RXSB_MODEM_VALID;
+			}
+
+			/* Check for valid data or RX errors */
+			if ((*sc & IOC4_RXSB_DATA_VALID) &&
+					((*sc & (IOC4_RXSB_PAR_ERR
+							| IOC4_RXSB_FRAME_ERR
+							| IOC4_RXSB_BREAK))
+					&& (port->ip_notify & (N_PARITY_ERROR
+							| N_FRAMING_ERROR
+							| N_BREAK)))) {
+				/* There is an error condition on the next byte.
+				 * If we have already transferred some bytes,
+				 * we'll stop here. Otherwise if this is the
+				 * first byte to be read, we'll just transfer
+				 * it alone after notifying the
+				 * upper layer of its status.
+				 */
+				if (total > 0) {
+					len = 0;
+					break;
+				} else {
+					if ((*sc & IOC4_RXSB_PAR_ERR) &&
+					   (port->ip_notify & N_PARITY_ERROR)) {
+						ioc4_cb_post_ncs(the_port,
+								NCS_PARITY);
+					}
+					if ((*sc & IOC4_RXSB_FRAME_ERR) &&
+					   (port->ip_notify & N_FRAMING_ERROR)){
+						ioc4_cb_post_ncs(the_port,
+								NCS_FRAMING);
+					}
+					if ((*sc & IOC4_RXSB_BREAK)
+					    && (port->ip_notify & N_BREAK)) {
+							ioc4_cb_post_ncs
+								    (the_port,
+								     NCS_BREAK);
+					}
+					len = 1;
+				}
+			}
+			if (*sc & IOC4_RXSB_DATA_VALID) {
+				*sc &= ~IOC4_RXSB_DATA_VALID;
+				*buf = entry->ring_data[byte_num];
+				buf++;
+				len--;
+				total++;
+			}
+		}
+
+		/* If we used up this entry entirely, go on to the next one,
+		 * otherwise we must have run out of buffer space, so
+		 * leave the consumer pointer here for the next read in case
+		 * there are still unread bytes in this entry.
+		 */
+		if ((entry->ring_allsc & RING_ANY_VALID) == 0) {
+			cons_ptr += (int)sizeof(struct ring_entry);
+			cons_ptr &= PROD_CONS_MASK;
+		}
+	}
+
+	/* Update consumer pointer and re-arm rx timer interrupt */
+	writel(cons_ptr, &port->ip_serial_regs->srcir);
+	port->ip_rx_cons = cons_ptr;
+
+	/* If we have now dipped below the rx high water mark and we have
+	 * rx_high interrupt turned off, we can now turn it back on again.
+	 */
+	if ((port->ip_flags & INPUT_HIGH) && (((prod_ptr - cons_ptr)
+			& PROD_CONS_MASK) < ((port->ip_sscr &
+				IOC4_SSCR_RX_THRESHOLD)
+					<< IOC4_PROD_CONS_PTR_OFF))) {
+		port->ip_flags &= ~INPUT_HIGH;
+		enable_intrs(port, hooks->intr_rx_high);
+	}
+	return total;
+}
+
+/**
+ * receive_chars - upper level read. Called with ip_lock.
+ * @the_port: port to read from
+ */
+static void receive_chars(struct uart_port *the_port)
+{
+	unsigned char ch[IOC4_MAX_CHARS];
+	int read_count, request_count = IOC4_MAX_CHARS;
+	struct uart_icount *icount;
+	struct uart_state *state = the_port->state;
+	unsigned long pflags;
+
+	/* Make sure all the pointers are "good" ones */
+	if (!state)
+		return;
+
+	spin_lock_irqsave(&the_port->lock, pflags);
+
+	request_count = tty_buffer_request_room(&state->port, IOC4_MAX_CHARS);
+
+	if (request_count > 0) {
+		icount = &the_port->icount;
+		read_count = do_read(the_port, ch, request_count);
+		if (read_count > 0) {
+			tty_insert_flip_string(&state->port, ch, read_count);
+			icount->rx += read_count;
+		}
+	}
+
+	spin_unlock_irqrestore(&the_port->lock, pflags);
+
+	tty_flip_buffer_push(&state->port);
+}
+
+/**
+ * ic4_type - What type of console are we?
+ * @port: Port to operate with (we ignore since we only have one port)
+ *
+ */
+static const char *ic4_type(struct uart_port *the_port)
+{
+	if (the_port->mapbase == PROTO_RS232)
+		return "SGI IOC4 Serial [rs232]";
+	else
+		return "SGI IOC4 Serial [rs422]";
+}
+
+/**
+ * ic4_tx_empty - Is the transmitter empty?
+ * @port: Port to operate on
+ *
+ */
+static unsigned int ic4_tx_empty(struct uart_port *the_port)
+{
+	struct ioc4_port *port = get_ioc4_port(the_port, 0);
+	unsigned int ret = 0;
+
+	if (port_is_active(port, the_port)) {
+		if (readl(&port->ip_serial_regs->shadow) & IOC4_SHADOW_TEMT)
+			ret = TIOCSER_TEMT;
+	}
+	return ret;
+}
+
+/**
+ * ic4_stop_tx - stop the transmitter
+ * @port: Port to operate on
+ *
+ */
+static void ic4_stop_tx(struct uart_port *the_port)
+{
+	struct ioc4_port *port = get_ioc4_port(the_port, 0);
+
+	if (port_is_active(port, the_port))
+		set_notification(port, N_OUTPUT_LOWAT, 0);
+}
+
+/**
+ * null_void_function -
+ * @port: Port to operate on
+ *
+ */
+static void null_void_function(struct uart_port *the_port)
+{
+}
+
+/**
+ * ic4_shutdown - shut down the port - free irq and disable
+ * @port: Port to shut down
+ *
+ */
+static void ic4_shutdown(struct uart_port *the_port)
+{
+	unsigned long port_flags;
+	struct ioc4_port *port;
+	struct uart_state *state;
+
+	port = get_ioc4_port(the_port, 0);
+	if (!port)
+		return;
+
+	state = the_port->state;
+	port->ip_port = NULL;
+
+	wake_up_interruptible(&state->port.delta_msr_wait);
+
+	if (state->port.tty)
+		set_bit(TTY_IO_ERROR, &state->port.tty->flags);
+
+	spin_lock_irqsave(&the_port->lock, port_flags);
+	set_notification(port, N_ALL, 0);
+	port->ip_flags = PORT_INACTIVE;
+	spin_unlock_irqrestore(&the_port->lock, port_flags);
+}
+
+/**
+ * ic4_set_mctrl - set control lines (dtr, rts, etc)
+ * @port: Port to operate on
+ * @mctrl: Lines to set/unset
+ *
+ */
+static void ic4_set_mctrl(struct uart_port *the_port, unsigned int mctrl)
+{
+	unsigned char mcr = 0;
+	struct ioc4_port *port;
+
+	port = get_ioc4_port(the_port, 0);
+	if (!port_is_active(port, the_port))
+		return;
+
+	if (mctrl & TIOCM_RTS)
+		mcr |= UART_MCR_RTS;
+	if (mctrl & TIOCM_DTR)
+		mcr |= UART_MCR_DTR;
+	if (mctrl & TIOCM_OUT1)
+		mcr |= UART_MCR_OUT1;
+	if (mctrl & TIOCM_OUT2)
+		mcr |= UART_MCR_OUT2;
+	if (mctrl & TIOCM_LOOP)
+		mcr |= UART_MCR_LOOP;
+
+	set_mcr(the_port, mcr, IOC4_SHADOW_DTR);
+}
+
+/**
+ * ic4_get_mctrl - get control line info
+ * @port: port to operate on
+ *
+ */
+static unsigned int ic4_get_mctrl(struct uart_port *the_port)
+{
+	struct ioc4_port *port = get_ioc4_port(the_port, 0);
+	uint32_t shadow;
+	unsigned int ret = 0;
+
+	if (!port_is_active(port, the_port))
+		return 0;
+
+	shadow = readl(&port->ip_serial_regs->shadow);
+	if (shadow & IOC4_SHADOW_DCD)
+		ret |= TIOCM_CAR;
+	if (shadow & IOC4_SHADOW_DR)
+		ret |= TIOCM_DSR;
+	if (shadow & IOC4_SHADOW_CTS)
+		ret |= TIOCM_CTS;
+	return ret;
+}
+
+/**
+ * ic4_start_tx - Start transmitter, flush any output
+ * @port: Port to operate on
+ *
+ */
+static void ic4_start_tx(struct uart_port *the_port)
+{
+	struct ioc4_port *port = get_ioc4_port(the_port, 0);
+
+	if (port_is_active(port, the_port)) {
+		set_notification(port, N_OUTPUT_LOWAT, 1);
+		enable_intrs(port, port->ip_hooks->intr_tx_mt);
+	}
+}
+
+/**
+ * ic4_break_ctl - handle breaks
+ * @port: Port to operate on
+ * @break_state: Break state
+ *
+ */
+static void ic4_break_ctl(struct uart_port *the_port, int break_state)
+{
+}
+
+/**
+ * ic4_startup - Start up the serial port
+ * @port: Port to operate on
+ *
+ */
+static int ic4_startup(struct uart_port *the_port)
+{
+	int retval;
+	struct ioc4_port *port;
+	struct ioc4_control *control;
+	struct uart_state *state;
+	unsigned long port_flags;
+
+	if (!the_port)
+		return -ENODEV;
+	port = get_ioc4_port(the_port, 1);
+	if (!port)
+		return -ENODEV;
+	state = the_port->state;
+
+	control = port->ip_control;
+	if (!control) {
+		port->ip_port = NULL;
+		return -ENODEV;
+	}
+
+	/* Start up the serial port */
+	spin_lock_irqsave(&the_port->lock, port_flags);
+	retval = ic4_startup_local(the_port);
+	spin_unlock_irqrestore(&the_port->lock, port_flags);
+	return retval;
+}
+
+/**
+ * ic4_set_termios - set termios stuff
+ * @port: port to operate on
+ * @termios: New settings
+ * @termios: Old
+ *
+ */
+static void
+ic4_set_termios(struct uart_port *the_port,
+		struct ktermios *termios, struct ktermios *old_termios)
+{
+	unsigned long port_flags;
+
+	spin_lock_irqsave(&the_port->lock, port_flags);
+	ioc4_change_speed(the_port, termios, old_termios);
+	spin_unlock_irqrestore(&the_port->lock, port_flags);
+}
+
+/**
+ * ic4_request_port - allocate resources for port - no op....
+ * @port: port to operate on
+ *
+ */
+static int ic4_request_port(struct uart_port *port)
+{
+	return 0;
+}
+
+/* Associate the uart functions above - given to serial core */
+
+static struct uart_ops ioc4_ops = {
+	.tx_empty	= ic4_tx_empty,
+	.set_mctrl	= ic4_set_mctrl,
+	.get_mctrl	= ic4_get_mctrl,
+	.stop_tx	= ic4_stop_tx,
+	.start_tx	= ic4_start_tx,
+	.stop_rx	= null_void_function,
+	.break_ctl	= ic4_break_ctl,
+	.startup	= ic4_startup,
+	.shutdown	= ic4_shutdown,
+	.set_termios	= ic4_set_termios,
+	.type		= ic4_type,
+	.release_port	= null_void_function,
+	.request_port	= ic4_request_port,
+};
+
+/*
+ * Boot-time initialization code
+ */
+
+static struct uart_driver ioc4_uart_rs232 = {
+	.owner		= THIS_MODULE,
+	.driver_name	= "ioc4_serial_rs232",
+	.dev_name	= DEVICE_NAME_RS232,
+	.major		= DEVICE_MAJOR,
+	.minor		= DEVICE_MINOR_RS232,
+	.nr		= IOC4_NUM_CARDS * IOC4_NUM_SERIAL_PORTS,
+};
+
+static struct uart_driver ioc4_uart_rs422 = {
+	.owner		= THIS_MODULE,
+	.driver_name	= "ioc4_serial_rs422",
+	.dev_name	= DEVICE_NAME_RS422,
+	.major		= DEVICE_MAJOR,
+	.minor		= DEVICE_MINOR_RS422,
+	.nr		= IOC4_NUM_CARDS * IOC4_NUM_SERIAL_PORTS,
+};
+
+
+/**
+ * ioc4_serial_remove_one - detach function
+ *
+ * @idd: IOC4 master module data for this IOC4
+ */
+
+static int ioc4_serial_remove_one(struct ioc4_driver_data *idd)
+{
+	int port_num, port_type;
+	struct ioc4_control *control;
+	struct uart_port *the_port;
+	struct ioc4_port *port;
+	struct ioc4_soft *soft;
+
+	/* If serial driver did not attach, don't try to detach */
+	control = idd->idd_serial_data;
+	if (!control)
+		return 0;
+
+	for (port_num = 0; port_num < IOC4_NUM_SERIAL_PORTS; port_num++) {
+		for (port_type = UART_PORT_MIN;
+					port_type < UART_PORT_COUNT;
+					port_type++) {
+			the_port = &control->ic_port[port_num].icp_uart_port
+							[port_type];
+			if (the_port) {
+				switch (port_type) {
+				case UART_PORT_RS422:
+					uart_remove_one_port(&ioc4_uart_rs422,
+							the_port);
+					break;
+				default:
+				case UART_PORT_RS232:
+					uart_remove_one_port(&ioc4_uart_rs232,
+							the_port);
+					break;
+				}
+			}
+		}
+		port = control->ic_port[port_num].icp_port;
+		/* we allocate in pairs */
+		if (!(port_num & 1) && port) {
+			pci_free_consistent(port->ip_pdev,
+					TOTAL_RING_BUF_SIZE,
+					port->ip_cpu_ringbuf,
+					port->ip_dma_ringbuf);
+			kfree(port);
+		}
+	}
+	soft = control->ic_soft;
+	if (soft) {
+		free_irq(control->ic_irq, soft);
+		if (soft->is_ioc4_serial_addr) {
+			iounmap(soft->is_ioc4_serial_addr);
+			release_mem_region((unsigned long)
+			     soft->is_ioc4_serial_addr,
+				sizeof(struct ioc4_serial));
+		}
+		kfree(soft);
+	}
+	kfree(control);
+	idd->idd_serial_data = NULL;
+
+	return 0;
+}
+
+
+/**
+ * ioc4_serial_core_attach_rs232 - register with serial core
+ *		This is done during pci probing
+ * @pdev: handle for this card
+ */
+static inline int
+ioc4_serial_core_attach(struct pci_dev *pdev, int port_type)
+{
+	struct ioc4_port *port;
+	struct uart_port *the_port;
+	struct ioc4_driver_data *idd = pci_get_drvdata(pdev);
+	struct ioc4_control *control = idd->idd_serial_data;
+	int port_num;
+	int port_type_idx;
+	struct uart_driver *u_driver;
+
+
+	DPRINT_CONFIG(("%s: attach pdev 0x%p - control 0x%p\n",
+			__func__, pdev, (void *)control));
+
+	if (!control)
+		return -ENODEV;
+
+	port_type_idx = (port_type == PROTO_RS232) ? UART_PORT_RS232
+						: UART_PORT_RS422;
+
+	u_driver = (port_type == PROTO_RS232)	? &ioc4_uart_rs232
+						: &ioc4_uart_rs422;
+
+	/* once around for each port on this card */
+	for (port_num = 0; port_num < IOC4_NUM_SERIAL_PORTS; port_num++) {
+		the_port = &control->ic_port[port_num].icp_uart_port
+							[port_type_idx];
+		port = control->ic_port[port_num].icp_port;
+		port->ip_all_ports[port_type_idx] = the_port;
+
+		DPRINT_CONFIG(("%s: attach the_port 0x%p / port 0x%p : type %s\n",
+				__func__, (void *)the_port,
+				(void *)port,
+				port_type == PROTO_RS232 ? "rs232" : "rs422"));
+
+		/* membase, iobase and mapbase just need to be non-0 */
+		the_port->membase = (unsigned char __iomem *)1;
+		the_port->iobase = (pdev->bus->number << 16) |  port_num;
+		the_port->line = (Num_of_ioc4_cards << 2) | port_num;
+		the_port->mapbase = port_type;
+		the_port->type = PORT_16550A;
+		the_port->fifosize = IOC4_FIFO_CHARS;
+		the_port->ops = &ioc4_ops;
+		the_port->irq = control->ic_irq;
+		the_port->dev = &pdev->dev;
+		spin_lock_init(&the_port->lock);
+		if (uart_add_one_port(u_driver, the_port) < 0) {
+			printk(KERN_WARNING
+		           "%s: unable to add port %d bus %d\n",
+			       __func__, the_port->line, pdev->bus->number);
+		} else {
+			DPRINT_CONFIG(
+			    ("IOC4 serial port %d irq = %d, bus %d\n",
+			       the_port->line, the_port->irq, pdev->bus->number));
+		}
+	}
+	return 0;
+}
+
+/**
+ * ioc4_serial_attach_one - register attach function
+ *		called per card found from IOC4 master module.
+ * @idd: Master module data for this IOC4
+ */
+static int
+ioc4_serial_attach_one(struct ioc4_driver_data *idd)
+{
+	unsigned long tmp_addr1;
+	struct ioc4_serial __iomem *serial;
+	struct ioc4_soft *soft;
+	struct ioc4_control *control;
+	int ret = 0;
+
+
+	DPRINT_CONFIG(("%s (0x%p, 0x%p)\n", __func__, idd->idd_pdev,
+							idd->idd_pci_id));
+
+	/* PCI-RT does not bring out serial connections.
+	 * Do not attach to this particular IOC4.
+	 */
+	if (idd->idd_variant == IOC4_VARIANT_PCI_RT)
+		return 0;
+
+	/* request serial registers */
+	tmp_addr1 = idd->idd_bar0 + IOC4_SERIAL_OFFSET;
+
+	if (!request_mem_region(tmp_addr1, sizeof(struct ioc4_serial),
+					"sioc4_uart")) {
+		printk(KERN_WARNING
+			"ioc4 (%p): unable to get request region for "
+				"uart space\n", (void *)idd->idd_pdev);
+		ret = -ENODEV;
+		goto out1;
+	}
+	serial = ioremap(tmp_addr1, sizeof(struct ioc4_serial));
+	if (!serial) {
+		printk(KERN_WARNING
+			 "ioc4 (%p) : unable to remap ioc4 serial register\n",
+				(void *)idd->idd_pdev);
+		ret = -ENODEV;
+		goto out2;
+	}
+	DPRINT_CONFIG(("%s : mem 0x%p, serial 0x%p\n",
+				__func__, (void *)idd->idd_misc_regs,
+				(void *)serial));
+
+	/* Get memory for the new card */
+	control = kzalloc(sizeof(struct ioc4_control), GFP_KERNEL);
+
+	if (!control) {
+		printk(KERN_WARNING "ioc4_attach_one"
+		       ": unable to get memory for the IOC4\n");
+		ret = -ENOMEM;
+		goto out2;
+	}
+	idd->idd_serial_data = control;
+
+	/* Allocate the soft structure */
+	soft = kzalloc(sizeof(struct ioc4_soft), GFP_KERNEL);
+	if (!soft) {
+		printk(KERN_WARNING
+		       "ioc4 (%p): unable to get memory for the soft struct\n",
+		       (void *)idd->idd_pdev);
+		ret = -ENOMEM;
+		goto out3;
+	}
+
+	spin_lock_init(&soft->is_ir_lock);
+	soft->is_ioc4_misc_addr = idd->idd_misc_regs;
+	soft->is_ioc4_serial_addr = serial;
+
+	/* Init the IOC4 */
+	writel(0xf << IOC4_SIO_CR_CMD_PULSE_SHIFT,
+	       &idd->idd_misc_regs->sio_cr.raw);
+
+	/* Enable serial port mode select generic PIO pins as outputs */
+	writel(IOC4_GPCR_UART0_MODESEL | IOC4_GPCR_UART1_MODESEL
+		| IOC4_GPCR_UART2_MODESEL | IOC4_GPCR_UART3_MODESEL,
+		&idd->idd_misc_regs->gpcr_s.raw);
+
+	/* Clear and disable all serial interrupts */
+	write_ireg(soft, ~0, IOC4_W_IEC, IOC4_SIO_INTR_TYPE);
+	writel(~0, &idd->idd_misc_regs->sio_ir.raw);
+	write_ireg(soft, IOC4_OTHER_IR_SER_MEMERR, IOC4_W_IEC,
+		   IOC4_OTHER_INTR_TYPE);
+	writel(IOC4_OTHER_IR_SER_MEMERR, &idd->idd_misc_regs->other_ir.raw);
+	control->ic_soft = soft;
+
+	/* Hook up interrupt handler */
+	if (!request_irq(idd->idd_pdev->irq, ioc4_intr, IRQF_SHARED,
+				"sgi-ioc4serial", soft)) {
+		control->ic_irq = idd->idd_pdev->irq;
+	} else {
+		printk(KERN_WARNING
+		    "%s : request_irq fails for IRQ 0x%x\n ",
+			__func__, idd->idd_pdev->irq);
+	}
+	ret = ioc4_attach_local(idd);
+	if (ret)
+		goto out4;
+
+	/* register port with the serial core - 1 rs232, 1 rs422 */
+
+	if ((ret = ioc4_serial_core_attach(idd->idd_pdev, PROTO_RS232)))
+		goto out4;
+
+	if ((ret = ioc4_serial_core_attach(idd->idd_pdev, PROTO_RS422)))
+		goto out5;
+
+	Num_of_ioc4_cards++;
+
+	return ret;
+
+	/* error exits that give back resources */
+out5:
+	ioc4_serial_remove_one(idd);
+	return ret;
+out4:
+	kfree(soft);
+out3:
+	kfree(control);
+out2:
+	if (serial)
+		iounmap(serial);
+	release_mem_region(tmp_addr1, sizeof(struct ioc4_serial));
+out1:
+
+	return ret;
+}
+
+
+static struct ioc4_submodule ioc4_serial_submodule = {
+	.is_name = "IOC4_serial",
+	.is_owner = THIS_MODULE,
+	.is_probe = ioc4_serial_attach_one,
+	.is_remove = ioc4_serial_remove_one,
+};
+
+/**
+ * ioc4_serial_init - module init
+ */
+static int __init ioc4_serial_init(void)
+{
+	int ret;
+
+	/* register with serial core */
+	if ((ret = uart_register_driver(&ioc4_uart_rs232)) < 0) {
+		printk(KERN_WARNING
+			"%s: Couldn't register rs232 IOC4 serial driver\n",
+			__func__);
+		goto out;
+	}
+	if ((ret = uart_register_driver(&ioc4_uart_rs422)) < 0) {
+		printk(KERN_WARNING
+			"%s: Couldn't register rs422 IOC4 serial driver\n",
+			__func__);
+		goto out_uart_rs232;
+	}
+
+	/* register with IOC4 main module */
+	ret = ioc4_register_submodule(&ioc4_serial_submodule);
+	if (ret)
+		goto out_uart_rs422;
+	return 0;
+
+out_uart_rs422:
+	uart_unregister_driver(&ioc4_uart_rs422);
+out_uart_rs232:
+	uart_unregister_driver(&ioc4_uart_rs232);
+out:
+	return ret;
+}
+
+static void __exit ioc4_serial_exit(void)
+{
+	ioc4_unregister_submodule(&ioc4_serial_submodule);
+	uart_unregister_driver(&ioc4_uart_rs232);
+	uart_unregister_driver(&ioc4_uart_rs422);
+}
+
+late_initcall(ioc4_serial_init); /* Call only after tty init is done */
+module_exit(ioc4_serial_exit);
+
+MODULE_AUTHOR("Pat Gefre - Silicon Graphics Inc. (SGI) <pfg@sgi.com>");
+MODULE_DESCRIPTION("Serial PCI driver module for SGI IOC4 Base-IO Card");
+MODULE_LICENSE("GPL");