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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/mips/pmcs-msp71xx/msp_serial.c
Initial import
Diffstat (limited to 'arch/mips/pmcs-msp71xx/msp_serial.c')
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1 files changed, 154 insertions, 0 deletions
diff --git a/arch/mips/pmcs-msp71xx/msp_serial.c b/arch/mips/pmcs-msp71xx/msp_serial.c
new file mode 100644
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+++ b/arch/mips/pmcs-msp71xx/msp_serial.c
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+/*
+ * The setup file for serial related hardware on PMC-Sierra MSP processors.
+ *
+ * Copyright 2005 PMC-Sierra, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
+ * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/serial.h>
+#include <linux/serial_core.h>
+#include <linux/serial_reg.h>
+#include <linux/slab.h>
+
+#include <asm/bootinfo.h>
+#include <asm/io.h>
+#include <asm/processor.h>
+#include <asm/serial.h>
+#include <linux/serial_8250.h>
+
+#include <msp_prom.h>
+#include <msp_int.h>
+#include <msp_regs.h>
+
+struct msp_uart_data {
+ int last_lcr;
+};
+
+static void msp_serial_out(struct uart_port *p, int offset, int value)
+{
+ struct msp_uart_data *d = p->private_data;
+
+ if (offset == UART_LCR)
+ d->last_lcr = value;
+
+ offset <<= p->regshift;
+ writeb(value, p->membase + offset);
+}
+
+static unsigned int msp_serial_in(struct uart_port *p, int offset)
+{
+ offset <<= p->regshift;
+
+ return readb(p->membase + offset);
+}
+
+static int msp_serial_handle_irq(struct uart_port *p)
+{
+ struct msp_uart_data *d = p->private_data;
+ unsigned int iir = readb(p->membase + (UART_IIR << p->regshift));
+
+ if (serial8250_handle_irq(p, iir)) {
+ return 1;
+ } else if ((iir & UART_IIR_BUSY) == UART_IIR_BUSY) {
+ /*
+ * The DesignWare APB UART has an Busy Detect (0x07) interrupt
+ * meaning an LCR write attempt occurred while the UART was
+ * busy. The interrupt must be cleared by reading the UART
+ * status register (USR) and the LCR re-written.
+ *
+ * Note: MSP reserves 0x20 bytes of address space for the UART
+ * and the USR is mapped in a separate block at an offset of
+ * 0xc0 from the start of the UART.
+ */
+ (void)readb(p->membase + 0xc0);
+ writeb(d->last_lcr, p->membase + (UART_LCR << p->regshift));
+
+ return 1;
+ }
+
+ return 0;
+}
+
+void __init msp_serial_setup(void)
+{
+ char *s;
+ char *endp;
+ struct uart_port up;
+ unsigned int uartclk;
+
+ memset(&up, 0, sizeof(up));
+
+ /* Check if clock was specified in environment */
+ s = prom_getenv("uartfreqhz");
+ if(!(s && *s && (uartclk = simple_strtoul(s, &endp, 10)) && *endp == 0))
+ uartclk = MSP_BASE_BAUD;
+ ppfinit("UART clock set to %d\n", uartclk);
+
+ /* Initialize first serial port */
+ up.mapbase = MSP_UART0_BASE;
+ up.membase = ioremap_nocache(up.mapbase, MSP_UART_REG_LEN);
+ up.irq = MSP_INT_UART0;
+ up.uartclk = uartclk;
+ up.regshift = 2;
+ up.iotype = UPIO_MEM;
+ up.flags = ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST;
+ up.type = PORT_16550A;
+ up.line = 0;
+ up.serial_out = msp_serial_out;
+ up.serial_in = msp_serial_in;
+ up.handle_irq = msp_serial_handle_irq;
+ up.private_data = kzalloc(sizeof(struct msp_uart_data), GFP_KERNEL);
+ if (!up.private_data) {
+ pr_err("failed to allocate uart private data\n");
+ return;
+ }
+ if (early_serial_setup(&up)) {
+ kfree(up.private_data);
+ pr_err("Early serial init of port 0 failed\n");
+ }
+
+ /* Initialize the second serial port, if one exists */
+ switch (mips_machtype) {
+ case MACH_MSP4200_EVAL:
+ case MACH_MSP4200_GW:
+ case MACH_MSP4200_FPGA:
+ case MACH_MSP7120_EVAL:
+ case MACH_MSP7120_GW:
+ case MACH_MSP7120_FPGA:
+ /* Enable UART1 on MSP4200 and MSP7120 */
+ *GPIO_CFG2_REG = 0x00002299;
+ break;
+
+ default:
+ return; /* No second serial port, good-bye. */
+ }
+
+ up.mapbase = MSP_UART1_BASE;
+ up.membase = ioremap_nocache(up.mapbase, MSP_UART_REG_LEN);
+ up.irq = MSP_INT_UART1;
+ up.line = 1;
+ up.private_data = (void*)UART1_STATUS_REG;
+ if (early_serial_setup(&up)) {
+ kfree(up.private_data);
+ pr_err("Early serial init of port 1 failed\n");
+ }
+}