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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-12-15 14:52:16 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-12-15 14:52:16 -0300
commit8d91c1e411f55d7ea91b1183a2e9f8088fb4d5be (patch)
treee9891aa6c295060d065adffd610c4f49ecf884f3 /drivers/tty/serial/atmel_serial.c
parenta71852147516bc1cb5b0b3cbd13639bfd4022dc8 (diff)
Linux-libre 4.3.2-gnu
Diffstat (limited to 'drivers/tty/serial/atmel_serial.c')
-rw-r--r--drivers/tty/serial/atmel_serial.c484
1 files changed, 315 insertions, 169 deletions
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 40326b342..538ea03bc 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -56,6 +56,15 @@
/* Revisit: We should calculate this based on the actual port settings */
#define PDC_RX_TIMEOUT (3 * 10) /* 3 bytes */
+/* The minium number of data FIFOs should be able to contain */
+#define ATMEL_MIN_FIFO_SIZE 8
+/*
+ * These two offsets are substracted from the RX FIFO size to define the RTS
+ * high and low thresholds
+ */
+#define ATMEL_RTS_HIGH_OFFSET 16
+#define ATMEL_RTS_LOW_OFFSET 20
+
#if defined(CONFIG_SERIAL_ATMEL_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
@@ -88,37 +97,6 @@ static void atmel_stop_rx(struct uart_port *port);
#define ATMEL_ISR_PASS_LIMIT 256
-/* UART registers. CR is write-only, hence no GET macro */
-#define UART_PUT_CR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_CR)
-#define UART_GET_MR(port) __raw_readl((port)->membase + ATMEL_US_MR)
-#define UART_PUT_MR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_MR)
-#define UART_PUT_IER(port,v) __raw_writel(v, (port)->membase + ATMEL_US_IER)
-#define UART_PUT_IDR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_IDR)
-#define UART_GET_IMR(port) __raw_readl((port)->membase + ATMEL_US_IMR)
-#define UART_GET_CSR(port) __raw_readl((port)->membase + ATMEL_US_CSR)
-#define UART_GET_CHAR(port) __raw_readl((port)->membase + ATMEL_US_RHR)
-#define UART_PUT_CHAR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_THR)
-#define UART_GET_BRGR(port) __raw_readl((port)->membase + ATMEL_US_BRGR)
-#define UART_PUT_BRGR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_BRGR)
-#define UART_PUT_RTOR(port,v) __raw_writel(v, (port)->membase + ATMEL_US_RTOR)
-#define UART_PUT_TTGR(port, v) __raw_writel(v, (port)->membase + ATMEL_US_TTGR)
-#define UART_GET_IP_NAME(port) __raw_readl((port)->membase + ATMEL_US_NAME)
-#define UART_GET_IP_VERSION(port) __raw_readl((port)->membase + ATMEL_US_VERSION)
-
- /* PDC registers */
-#define UART_PUT_PTCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_PTCR)
-#define UART_GET_PTSR(port) __raw_readl((port)->membase + ATMEL_PDC_PTSR)
-
-#define UART_PUT_RPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RPR)
-#define UART_GET_RPR(port) __raw_readl((port)->membase + ATMEL_PDC_RPR)
-#define UART_PUT_RCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RCR)
-#define UART_PUT_RNPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RNPR)
-#define UART_PUT_RNCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RNCR)
-
-#define UART_PUT_TPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TPR)
-#define UART_PUT_TCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TCR)
-#define UART_GET_TCR(port) __raw_readl((port)->membase + ATMEL_PDC_TCR)
-
struct atmel_dma_buffer {
unsigned char *buf;
dma_addr_t dma_addr;
@@ -166,12 +144,16 @@ struct atmel_uart_port {
unsigned int irq_status;
unsigned int irq_status_prev;
unsigned int status_change;
+ unsigned int tx_len;
struct circ_buf rx_ring;
struct mctrl_gpios *gpios;
int gpio_irq[UART_GPIO_MAX];
unsigned int tx_done_mask;
+ u32 fifo_size;
+ u32 rts_high;
+ u32 rts_low;
bool ms_irq_enabled;
bool is_usart; /* usart or uart */
struct timer_list uart_timer; /* uart timer */
@@ -212,6 +194,43 @@ to_atmel_uart_port(struct uart_port *uart)
return container_of(uart, struct atmel_uart_port, uart);
}
+static inline u32 atmel_uart_readl(struct uart_port *port, u32 reg)
+{
+ return __raw_readl(port->membase + reg);
+}
+
+static inline void atmel_uart_writel(struct uart_port *port, u32 reg, u32 value)
+{
+ __raw_writel(value, port->membase + reg);
+}
+
+#ifdef CONFIG_AVR32
+
+/* AVR32 cannot handle 8 or 16bit I/O accesses but only 32bit I/O accesses */
+static inline u8 atmel_uart_read_char(struct uart_port *port)
+{
+ return __raw_readl(port->membase + ATMEL_US_RHR);
+}
+
+static inline void atmel_uart_write_char(struct uart_port *port, u8 value)
+{
+ __raw_writel(value, port->membase + ATMEL_US_THR);
+}
+
+#else
+
+static inline u8 atmel_uart_read_char(struct uart_port *port)
+{
+ return __raw_readb(port->membase + ATMEL_US_RHR);
+}
+
+static inline void atmel_uart_write_char(struct uart_port *port, u8 value)
+{
+ __raw_writeb(value, port->membase + ATMEL_US_THR);
+}
+
+#endif
+
#ifdef CONFIG_SERIAL_ATMEL_PDC
static bool atmel_use_pdc_rx(struct uart_port *port)
{
@@ -257,7 +276,7 @@ static unsigned int atmel_get_lines_status(struct uart_port *port)
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
unsigned int status, ret = 0;
- status = UART_GET_CSR(port);
+ status = atmel_uart_readl(port, ATMEL_US_CSR);
mctrl_gpio_get(atmel_port->gpios, &ret);
@@ -304,9 +323,9 @@ static int atmel_config_rs485(struct uart_port *port,
unsigned int mode;
/* Disable interrupts */
- UART_PUT_IDR(port, atmel_port->tx_done_mask);
+ atmel_uart_writel(port, ATMEL_US_IDR, atmel_port->tx_done_mask);
- mode = UART_GET_MR(port);
+ mode = atmel_uart_readl(port, ATMEL_US_MR);
/* Resetting serial mode to RS232 (0x0) */
mode &= ~ATMEL_US_USMODE;
@@ -316,7 +335,8 @@ static int atmel_config_rs485(struct uart_port *port,
if (rs485conf->flags & SER_RS485_ENABLED) {
dev_dbg(port->dev, "Setting UART to RS485\n");
atmel_port->tx_done_mask = ATMEL_US_TXEMPTY;
- UART_PUT_TTGR(port, rs485conf->delay_rts_after_send);
+ atmel_uart_writel(port, ATMEL_US_TTGR,
+ rs485conf->delay_rts_after_send);
mode |= ATMEL_US_USMODE_RS485;
} else {
dev_dbg(port->dev, "Setting UART to RS232\n");
@@ -326,10 +346,10 @@ static int atmel_config_rs485(struct uart_port *port,
else
atmel_port->tx_done_mask = ATMEL_US_TXRDY;
}
- UART_PUT_MR(port, mode);
+ atmel_uart_writel(port, ATMEL_US_MR, mode);
/* Enable interrupts */
- UART_PUT_IER(port, atmel_port->tx_done_mask);
+ atmel_uart_writel(port, ATMEL_US_IER, atmel_port->tx_done_mask);
return 0;
}
@@ -339,7 +359,9 @@ static int atmel_config_rs485(struct uart_port *port,
*/
static u_int atmel_tx_empty(struct uart_port *port)
{
- return (UART_GET_CSR(port) & ATMEL_US_TXEMPTY) ? TIOCSER_TEMT : 0;
+ return (atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXEMPTY) ?
+ TIOCSER_TEMT :
+ 0;
}
/*
@@ -348,13 +370,14 @@ static u_int atmel_tx_empty(struct uart_port *port)
static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
{
unsigned int control = 0;
- unsigned int mode = UART_GET_MR(port);
+ unsigned int mode = atmel_uart_readl(port, ATMEL_US_MR);
unsigned int rts_paused, rts_ready;
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
/* override mode to RS485 if needed, otherwise keep the current mode */
if (port->rs485.flags & SER_RS485_ENABLED) {
- UART_PUT_TTGR(port, port->rs485.delay_rts_after_send);
+ atmel_uart_writel(port, ATMEL_US_TTGR,
+ port->rs485.delay_rts_after_send);
mode &= ~ATMEL_US_USMODE;
mode |= ATMEL_US_USMODE_RS485;
}
@@ -384,7 +407,7 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
else
control |= ATMEL_US_DTRDIS;
- UART_PUT_CR(port, control);
+ atmel_uart_writel(port, ATMEL_US_CR, control);
mctrl_gpio_set(atmel_port->gpios, mctrl);
@@ -395,7 +418,7 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
else
mode |= ATMEL_US_CHMODE_NORMAL;
- UART_PUT_MR(port, mode);
+ atmel_uart_writel(port, ATMEL_US_MR, mode);
}
/*
@@ -406,7 +429,7 @@ static u_int atmel_get_mctrl(struct uart_port *port)
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
unsigned int ret = 0, status;
- status = UART_GET_CSR(port);
+ status = atmel_uart_readl(port, ATMEL_US_CSR);
/*
* The control signals are active low.
@@ -432,10 +455,10 @@ static void atmel_stop_tx(struct uart_port *port)
if (atmel_use_pdc_tx(port)) {
/* disable PDC transmit */
- UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
+ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS);
}
/* Disable interrupts */
- UART_PUT_IDR(port, atmel_port->tx_done_mask);
+ atmel_uart_writel(port, ATMEL_US_IDR, atmel_port->tx_done_mask);
if ((port->rs485.flags & SER_RS485_ENABLED) &&
!(port->rs485.flags & SER_RS485_RX_DURING_TX))
@@ -450,7 +473,7 @@ static void atmel_start_tx(struct uart_port *port)
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
if (atmel_use_pdc_tx(port)) {
- if (UART_GET_PTSR(port) & ATMEL_PDC_TXTEN)
+ if (atmel_uart_readl(port, ATMEL_PDC_PTSR) & ATMEL_PDC_TXTEN)
/* The transmitter is already running. Yes, we
really need this.*/
return;
@@ -460,10 +483,10 @@ static void atmel_start_tx(struct uart_port *port)
atmel_stop_rx(port);
/* re-enable PDC transmit */
- UART_PUT_PTCR(port, ATMEL_PDC_TXTEN);
+ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
}
/* Enable interrupts */
- UART_PUT_IER(port, atmel_port->tx_done_mask);
+ atmel_uart_writel(port, ATMEL_US_IER, atmel_port->tx_done_mask);
}
/*
@@ -471,17 +494,19 @@ static void atmel_start_tx(struct uart_port *port)
*/
static void atmel_start_rx(struct uart_port *port)
{
- UART_PUT_CR(port, ATMEL_US_RSTSTA); /* reset status and receiver */
+ /* reset status and receiver */
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA);
- UART_PUT_CR(port, ATMEL_US_RXEN);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RXEN);
if (atmel_use_pdc_rx(port)) {
/* enable PDC controller */
- UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT |
- port->read_status_mask);
- UART_PUT_PTCR(port, ATMEL_PDC_RXTEN);
+ atmel_uart_writel(port, ATMEL_US_IER,
+ ATMEL_US_ENDRX | ATMEL_US_TIMEOUT |
+ port->read_status_mask);
+ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
} else {
- UART_PUT_IER(port, ATMEL_US_RXRDY);
+ atmel_uart_writel(port, ATMEL_US_IER, ATMEL_US_RXRDY);
}
}
@@ -490,15 +515,16 @@ static void atmel_start_rx(struct uart_port *port)
*/
static void atmel_stop_rx(struct uart_port *port)
{
- UART_PUT_CR(port, ATMEL_US_RXDIS);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RXDIS);
if (atmel_use_pdc_rx(port)) {
/* disable PDC receive */
- UART_PUT_PTCR(port, ATMEL_PDC_RXTDIS);
- UART_PUT_IDR(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT |
- port->read_status_mask);
+ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS);
+ atmel_uart_writel(port, ATMEL_US_IDR,
+ ATMEL_US_ENDRX | ATMEL_US_TIMEOUT |
+ port->read_status_mask);
} else {
- UART_PUT_IDR(port, ATMEL_US_RXRDY);
+ atmel_uart_writel(port, ATMEL_US_IDR, ATMEL_US_RXRDY);
}
}
@@ -538,7 +564,7 @@ static void atmel_enable_ms(struct uart_port *port)
else
ier |= ATMEL_US_DCDIC;
- UART_PUT_IER(port, ier);
+ atmel_uart_writel(port, ATMEL_US_IER, ier);
}
/*
@@ -577,7 +603,7 @@ static void atmel_disable_ms(struct uart_port *port)
else
idr |= ATMEL_US_DCDIC;
- UART_PUT_IDR(port, idr);
+ atmel_uart_writel(port, ATMEL_US_IDR, idr);
}
/*
@@ -586,9 +612,11 @@ static void atmel_disable_ms(struct uart_port *port)
static void atmel_break_ctl(struct uart_port *port, int break_state)
{
if (break_state != 0)
- UART_PUT_CR(port, ATMEL_US_STTBRK); /* start break */
+ /* start break */
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STTBRK);
else
- UART_PUT_CR(port, ATMEL_US_STPBRK); /* stop break */
+ /* stop break */
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STPBRK);
}
/*
@@ -622,7 +650,7 @@ atmel_buffer_rx_char(struct uart_port *port, unsigned int status,
static void atmel_pdc_rxerr(struct uart_port *port, unsigned int status)
{
/* clear error */
- UART_PUT_CR(port, ATMEL_US_RSTSTA);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA);
if (status & ATMEL_US_RXBRK) {
/* ignore side-effect */
@@ -645,9 +673,9 @@ static void atmel_rx_chars(struct uart_port *port)
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
unsigned int status, ch;
- status = UART_GET_CSR(port);
+ status = atmel_uart_readl(port, ATMEL_US_CSR);
while (status & ATMEL_US_RXRDY) {
- ch = UART_GET_CHAR(port);
+ ch = atmel_uart_read_char(port);
/*
* note that the error handling code is
@@ -658,12 +686,13 @@ static void atmel_rx_chars(struct uart_port *port)
|| atmel_port->break_active)) {
/* clear error */
- UART_PUT_CR(port, ATMEL_US_RSTSTA);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA);
if (status & ATMEL_US_RXBRK
&& !atmel_port->break_active) {
atmel_port->break_active = 1;
- UART_PUT_IER(port, ATMEL_US_RXBRK);
+ atmel_uart_writel(port, ATMEL_US_IER,
+ ATMEL_US_RXBRK);
} else {
/*
* This is either the end-of-break
@@ -672,14 +701,15 @@ static void atmel_rx_chars(struct uart_port *port)
* being set. In both cases, the next
* RXBRK will indicate start-of-break.
*/
- UART_PUT_IDR(port, ATMEL_US_RXBRK);
+ atmel_uart_writel(port, ATMEL_US_IDR,
+ ATMEL_US_RXBRK);
status &= ~ATMEL_US_RXBRK;
atmel_port->break_active = 0;
}
}
atmel_buffer_rx_char(port, status, ch);
- status = UART_GET_CSR(port);
+ status = atmel_uart_readl(port, ATMEL_US_CSR);
}
tasklet_schedule(&atmel_port->tasklet);
@@ -694,16 +724,18 @@ static void atmel_tx_chars(struct uart_port *port)
struct circ_buf *xmit = &port->state->xmit;
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- if (port->x_char && UART_GET_CSR(port) & atmel_port->tx_done_mask) {
- UART_PUT_CHAR(port, port->x_char);
+ if (port->x_char &&
+ (atmel_uart_readl(port, ATMEL_US_CSR) & atmel_port->tx_done_mask)) {
+ atmel_uart_write_char(port, port->x_char);
port->icount.tx++;
port->x_char = 0;
}
if (uart_circ_empty(xmit) || uart_tx_stopped(port))
return;
- while (UART_GET_CSR(port) & atmel_port->tx_done_mask) {
- UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
+ while (atmel_uart_readl(port, ATMEL_US_CSR) &
+ atmel_port->tx_done_mask) {
+ atmel_uart_write_char(port, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
if (uart_circ_empty(xmit))
@@ -715,7 +747,8 @@ static void atmel_tx_chars(struct uart_port *port)
if (!uart_circ_empty(xmit))
/* Enable interrupts */
- UART_PUT_IER(port, atmel_port->tx_done_mask);
+ atmel_uart_writel(port, ATMEL_US_IER,
+ atmel_port->tx_done_mask);
}
static void atmel_complete_tx_dma(void *arg)
@@ -730,10 +763,10 @@ static void atmel_complete_tx_dma(void *arg)
if (chan)
dmaengine_terminate_all(chan);
- xmit->tail += sg_dma_len(&atmel_port->sg_tx);
+ xmit->tail += atmel_port->tx_len;
xmit->tail &= UART_XMIT_SIZE - 1;
- port->icount.tx += sg_dma_len(&atmel_port->sg_tx);
+ port->icount.tx += atmel_port->tx_len;
spin_lock_irq(&atmel_port->lock_tx);
async_tx_ack(atmel_port->desc_tx);
@@ -781,7 +814,9 @@ static void atmel_tx_dma(struct uart_port *port)
struct circ_buf *xmit = &port->state->xmit;
struct dma_chan *chan = atmel_port->chan_tx;
struct dma_async_tx_descriptor *desc;
- struct scatterlist *sg = &atmel_port->sg_tx;
+ struct scatterlist sgl[2], *sg, *sg_tx = &atmel_port->sg_tx;
+ unsigned int tx_len, part1_len, part2_len, sg_len;
+ dma_addr_t phys_addr;
/* Make sure we have an idle channel */
if (atmel_port->desc_tx != NULL)
@@ -797,18 +832,46 @@ static void atmel_tx_dma(struct uart_port *port)
* Take the port lock to get a
* consistent xmit buffer state.
*/
- sg->offset = xmit->tail & (UART_XMIT_SIZE - 1);
- sg_dma_address(sg) = (sg_dma_address(sg) &
- ~(UART_XMIT_SIZE - 1))
- + sg->offset;
- sg_dma_len(sg) = CIRC_CNT_TO_END(xmit->head,
- xmit->tail,
- UART_XMIT_SIZE);
- BUG_ON(!sg_dma_len(sg));
+ tx_len = CIRC_CNT_TO_END(xmit->head,
+ xmit->tail,
+ UART_XMIT_SIZE);
+
+ if (atmel_port->fifo_size) {
+ /* multi data mode */
+ part1_len = (tx_len & ~0x3); /* DWORD access */
+ part2_len = (tx_len & 0x3); /* BYTE access */
+ } else {
+ /* single data (legacy) mode */
+ part1_len = 0;
+ part2_len = tx_len; /* BYTE access only */
+ }
+
+ sg_init_table(sgl, 2);
+ sg_len = 0;
+ phys_addr = sg_dma_address(sg_tx) + xmit->tail;
+ if (part1_len) {
+ sg = &sgl[sg_len++];
+ sg_dma_address(sg) = phys_addr;
+ sg_dma_len(sg) = part1_len;
+
+ phys_addr += part1_len;
+ }
+
+ if (part2_len) {
+ sg = &sgl[sg_len++];
+ sg_dma_address(sg) = phys_addr;
+ sg_dma_len(sg) = part2_len;
+ }
+
+ /*
+ * save tx_len so atmel_complete_tx_dma() will increase
+ * xmit->tail correctly
+ */
+ atmel_port->tx_len = tx_len;
desc = dmaengine_prep_slave_sg(chan,
- sg,
- 1,
+ sgl,
+ sg_len,
DMA_MEM_TO_DEV,
DMA_PREP_INTERRUPT |
DMA_CTRL_ACK);
@@ -817,7 +880,7 @@ static void atmel_tx_dma(struct uart_port *port)
return;
}
- dma_sync_sg_for_device(port->dev, sg, 1, DMA_TO_DEVICE);
+ dma_sync_sg_for_device(port->dev, sg_tx, 1, DMA_TO_DEVICE);
atmel_port->desc_tx = desc;
desc->callback = atmel_complete_tx_dma;
@@ -877,7 +940,9 @@ static int atmel_prepare_tx_dma(struct uart_port *port)
/* Configure the slave DMA */
memset(&config, 0, sizeof(config));
config.direction = DMA_MEM_TO_DEV;
- config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ config.dst_addr_width = (atmel_port->fifo_size) ?
+ DMA_SLAVE_BUSWIDTH_4_BYTES :
+ DMA_SLAVE_BUSWIDTH_1_BYTE;
config.dst_addr = port->mapbase + ATMEL_US_THR;
config.dst_maxburst = 1;
@@ -935,14 +1000,14 @@ static void atmel_rx_from_dma(struct uart_port *port)
/* Reset the UART timeout early so that we don't miss one */
- UART_PUT_CR(port, ATMEL_US_STTTO);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STTTO);
dmastat = dmaengine_tx_status(chan,
atmel_port->cookie_rx,
&state);
/* Restart a new tasklet if DMA status is error */
if (dmastat == DMA_ERROR) {
dev_dbg(port->dev, "Get residue error, restart tasklet\n");
- UART_PUT_IER(port, ATMEL_US_TIMEOUT);
+ atmel_uart_writel(port, ATMEL_US_IER, ATMEL_US_TIMEOUT);
tasklet_schedule(&atmel_port->tasklet);
return;
}
@@ -1008,7 +1073,7 @@ static void atmel_rx_from_dma(struct uart_port *port)
tty_flip_buffer_push(tport);
spin_lock(&port->lock);
- UART_PUT_IER(port, ATMEL_US_TIMEOUT);
+ atmel_uart_writel(port, ATMEL_US_IER, ATMEL_US_TIMEOUT);
}
static int atmel_prepare_rx_dma(struct uart_port *port)
@@ -1118,8 +1183,8 @@ atmel_handle_receive(struct uart_port *port, unsigned int pending)
* the moment.
*/
if (pending & (ATMEL_US_ENDRX | ATMEL_US_TIMEOUT)) {
- UART_PUT_IDR(port, (ATMEL_US_ENDRX
- | ATMEL_US_TIMEOUT));
+ atmel_uart_writel(port, ATMEL_US_IDR,
+ (ATMEL_US_ENDRX | ATMEL_US_TIMEOUT));
tasklet_schedule(&atmel_port->tasklet);
}
@@ -1130,7 +1195,8 @@ atmel_handle_receive(struct uart_port *port, unsigned int pending)
if (atmel_use_dma_rx(port)) {
if (pending & ATMEL_US_TIMEOUT) {
- UART_PUT_IDR(port, ATMEL_US_TIMEOUT);
+ atmel_uart_writel(port, ATMEL_US_IDR,
+ ATMEL_US_TIMEOUT);
tasklet_schedule(&atmel_port->tasklet);
}
}
@@ -1143,8 +1209,8 @@ atmel_handle_receive(struct uart_port *port, unsigned int pending)
* End of break detected. If it came along with a
* character, atmel_rx_chars will handle it.
*/
- UART_PUT_CR(port, ATMEL_US_RSTSTA);
- UART_PUT_IDR(port, ATMEL_US_RXBRK);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA);
+ atmel_uart_writel(port, ATMEL_US_IDR, ATMEL_US_RXBRK);
atmel_port->break_active = 0;
}
}
@@ -1159,7 +1225,8 @@ atmel_handle_transmit(struct uart_port *port, unsigned int pending)
if (pending & atmel_port->tx_done_mask) {
/* Either PDC or interrupt transmission */
- UART_PUT_IDR(port, atmel_port->tx_done_mask);
+ atmel_uart_writel(port, ATMEL_US_IDR,
+ atmel_port->tx_done_mask);
tasklet_schedule(&atmel_port->tasklet);
}
}
@@ -1197,7 +1264,7 @@ static irqreturn_t atmel_interrupt(int irq, void *dev_id)
do {
status = atmel_get_lines_status(port);
- mask = UART_GET_IMR(port);
+ mask = atmel_uart_readl(port, ATMEL_US_IMR);
pending = status & mask;
if (!gpio_handled) {
/*
@@ -1223,7 +1290,7 @@ static irqreturn_t atmel_interrupt(int irq, void *dev_id)
if (atmel_port->suspended) {
atmel_port->pending |= pending;
atmel_port->pending_status = status;
- UART_PUT_IDR(port, mask);
+ atmel_uart_writel(port, ATMEL_US_IDR, mask);
pm_system_wakeup();
break;
}
@@ -1260,7 +1327,7 @@ static void atmel_tx_pdc(struct uart_port *port)
int count;
/* nothing left to transmit? */
- if (UART_GET_TCR(port))
+ if (atmel_uart_readl(port, ATMEL_PDC_TCR))
return;
xmit->tail += pdc->ofs;
@@ -1272,7 +1339,7 @@ static void atmel_tx_pdc(struct uart_port *port)
/* more to transmit - setup next transfer */
/* disable PDC transmit */
- UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
+ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS);
if (!uart_circ_empty(xmit) && !uart_tx_stopped(port)) {
dma_sync_single_for_device(port->dev,
@@ -1283,12 +1350,14 @@ static void atmel_tx_pdc(struct uart_port *port)
count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
pdc->ofs = count;
- UART_PUT_TPR(port, pdc->dma_addr + xmit->tail);
- UART_PUT_TCR(port, count);
+ atmel_uart_writel(port, ATMEL_PDC_TPR,
+ pdc->dma_addr + xmit->tail);
+ atmel_uart_writel(port, ATMEL_PDC_TCR, count);
/* re-enable PDC transmit */
- UART_PUT_PTCR(port, ATMEL_PDC_TXTEN);
+ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
/* Enable interrupts */
- UART_PUT_IER(port, atmel_port->tx_done_mask);
+ atmel_uart_writel(port, ATMEL_US_IER,
+ atmel_port->tx_done_mask);
} else {
if ((port->rs485.flags & SER_RS485_ENABLED) &&
!(port->rs485.flags & SER_RS485_RX_DURING_TX)) {
@@ -1414,10 +1483,10 @@ static void atmel_rx_from_pdc(struct uart_port *port)
do {
/* Reset the UART timeout early so that we don't miss one */
- UART_PUT_CR(port, ATMEL_US_STTTO);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STTTO);
pdc = &atmel_port->pdc_rx[rx_idx];
- head = UART_GET_RPR(port) - pdc->dma_addr;
+ head = atmel_uart_readl(port, ATMEL_PDC_RPR) - pdc->dma_addr;
tail = pdc->ofs;
/* If the PDC has switched buffers, RPR won't contain
@@ -1460,8 +1529,8 @@ static void atmel_rx_from_pdc(struct uart_port *port)
*/
if (head >= pdc->dma_size) {
pdc->ofs = 0;
- UART_PUT_RNPR(port, pdc->dma_addr);
- UART_PUT_RNCR(port, pdc->dma_size);
+ atmel_uart_writel(port, ATMEL_PDC_RNPR, pdc->dma_addr);
+ atmel_uart_writel(port, ATMEL_PDC_RNCR, pdc->dma_size);
rx_idx = !rx_idx;
atmel_port->pdc_rx_idx = rx_idx;
@@ -1476,7 +1545,8 @@ static void atmel_rx_from_pdc(struct uart_port *port)
tty_flip_buffer_push(tport);
spin_lock(&port->lock);
- UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
+ atmel_uart_writel(port, ATMEL_US_IER,
+ ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
}
static int atmel_prepare_rx_pdc(struct uart_port *port)
@@ -1509,11 +1579,12 @@ static int atmel_prepare_rx_pdc(struct uart_port *port)
atmel_port->pdc_rx_idx = 0;
- UART_PUT_RPR(port, atmel_port->pdc_rx[0].dma_addr);
- UART_PUT_RCR(port, PDC_BUFFER_SIZE);
+ atmel_uart_writel(port, ATMEL_PDC_RPR, atmel_port->pdc_rx[0].dma_addr);
+ atmel_uart_writel(port, ATMEL_PDC_RCR, PDC_BUFFER_SIZE);
- UART_PUT_RNPR(port, atmel_port->pdc_rx[1].dma_addr);
- UART_PUT_RNCR(port, PDC_BUFFER_SIZE);
+ atmel_uart_writel(port, ATMEL_PDC_RNPR,
+ atmel_port->pdc_rx[1].dma_addr);
+ atmel_uart_writel(port, ATMEL_PDC_RNCR, PDC_BUFFER_SIZE);
return 0;
}
@@ -1667,7 +1738,7 @@ static void atmel_set_ops(struct uart_port *port)
static void atmel_get_ip_name(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- int name = UART_GET_IP_NAME(port);
+ int name = atmel_uart_readl(port, ATMEL_US_NAME);
u32 version;
int usart, uart;
/* usart and uart ascii */
@@ -1684,7 +1755,7 @@ static void atmel_get_ip_name(struct uart_port *port)
atmel_port->is_usart = false;
} else {
/* fallback for older SoCs: use version field */
- version = UART_GET_IP_VERSION(port);
+ version = atmel_uart_readl(port, ATMEL_US_VERSION);
switch (version) {
case 0x302:
case 0x10213:
@@ -1756,7 +1827,7 @@ static int atmel_startup(struct uart_port *port)
* request_irq() is called we could get stuck trying to
* handle an unexpected interrupt
*/
- UART_PUT_IDR(port, -1);
+ atmel_uart_writel(port, ATMEL_US_IDR, -1);
atmel_port->ms_irq_enabled = false;
/*
@@ -1797,6 +1868,32 @@ static int atmel_startup(struct uart_port *port)
atmel_set_ops(port);
}
+ /*
+ * Enable FIFO when available
+ */
+ if (atmel_port->fifo_size) {
+ unsigned int txrdym = ATMEL_US_ONE_DATA;
+ unsigned int rxrdym = ATMEL_US_ONE_DATA;
+ unsigned int fmr;
+
+ atmel_uart_writel(port, ATMEL_US_CR,
+ ATMEL_US_FIFOEN |
+ ATMEL_US_RXFCLR |
+ ATMEL_US_TXFLCLR);
+
+ if (atmel_use_dma_tx(port))
+ txrdym = ATMEL_US_FOUR_DATA;
+
+ fmr = ATMEL_US_TXRDYM(txrdym) | ATMEL_US_RXRDYM(rxrdym);
+ if (atmel_port->rts_high &&
+ atmel_port->rts_low)
+ fmr |= ATMEL_US_FRTSC |
+ ATMEL_US_RXFTHRES(atmel_port->rts_high) |
+ ATMEL_US_RXFTHRES2(atmel_port->rts_low);
+
+ atmel_uart_writel(port, ATMEL_US_FMR, fmr);
+ }
+
/* Save current CSR for comparison in atmel_tasklet_func() */
atmel_port->irq_status_prev = atmel_get_lines_status(port);
atmel_port->irq_status = atmel_port->irq_status_prev;
@@ -1804,9 +1901,9 @@ static int atmel_startup(struct uart_port *port)
/*
* Finally, enable the serial port
*/
- UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
/* enable xmit & rcvr */
- UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN | ATMEL_US_RXEN);
setup_timer(&atmel_port->uart_timer,
atmel_uart_timer_callback,
@@ -1819,13 +1916,14 @@ static int atmel_startup(struct uart_port *port)
jiffies + uart_poll_timeout(port));
/* set USART timeout */
} else {
- UART_PUT_RTOR(port, PDC_RX_TIMEOUT);
- UART_PUT_CR(port, ATMEL_US_STTTO);
+ atmel_uart_writel(port, ATMEL_US_RTOR, PDC_RX_TIMEOUT);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STTTO);
- UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
+ atmel_uart_writel(port, ATMEL_US_IER,
+ ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
}
/* enable PDC controller */
- UART_PUT_PTCR(port, ATMEL_PDC_RXTEN);
+ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
} else if (atmel_use_dma_rx(port)) {
/* set UART timeout */
if (!atmel_port->is_usart) {
@@ -1833,14 +1931,15 @@ static int atmel_startup(struct uart_port *port)
jiffies + uart_poll_timeout(port));
/* set USART timeout */
} else {
- UART_PUT_RTOR(port, PDC_RX_TIMEOUT);
- UART_PUT_CR(port, ATMEL_US_STTTO);
+ atmel_uart_writel(port, ATMEL_US_RTOR, PDC_RX_TIMEOUT);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_STTTO);
- UART_PUT_IER(port, ATMEL_US_TIMEOUT);
+ atmel_uart_writel(port, ATMEL_US_IER,
+ ATMEL_US_TIMEOUT);
}
} else {
/* enable receive only */
- UART_PUT_IER(port, ATMEL_US_RXRDY);
+ atmel_uart_writel(port, ATMEL_US_IER, ATMEL_US_RXRDY);
}
return 0;
@@ -1860,7 +1959,7 @@ static void atmel_flush_buffer(struct uart_port *port)
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
if (atmel_use_pdc_tx(port)) {
- UART_PUT_TCR(port, 0);
+ atmel_uart_writel(port, ATMEL_PDC_TCR, 0);
atmel_port->pdc_tx.ofs = 0;
}
}
@@ -1892,8 +1991,8 @@ static void atmel_shutdown(struct uart_port *port)
atmel_stop_rx(port);
atmel_stop_tx(port);
- UART_PUT_CR(port, ATMEL_US_RSTSTA);
- UART_PUT_IDR(port, -1);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA);
+ atmel_uart_writel(port, ATMEL_US_IDR, -1);
/*
@@ -1938,12 +2037,12 @@ static void atmel_serial_pm(struct uart_port *port, unsigned int state,
clk_prepare_enable(atmel_port->clk);
/* re-enable interrupts if we disabled some on suspend */
- UART_PUT_IER(port, atmel_port->backup_imr);
+ atmel_uart_writel(port, ATMEL_US_IER, atmel_port->backup_imr);
break;
case 3:
/* Back up the interrupt mask and disable all interrupts */
- atmel_port->backup_imr = UART_GET_IMR(port);
- UART_PUT_IDR(port, -1);
+ atmel_port->backup_imr = atmel_uart_readl(port, ATMEL_US_IMR);
+ atmel_uart_writel(port, ATMEL_US_IDR, -1);
/*
* Disable the peripheral clock for this serial port.
@@ -1966,7 +2065,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
unsigned int old_mode, mode, imr, quot, baud;
/* save the current mode register */
- mode = old_mode = UART_GET_MR(port);
+ mode = old_mode = atmel_uart_readl(port, ATMEL_US_MR);
/* reset the mode, clock divisor, parity, stop bits and data size */
mode &= ~(ATMEL_US_USCLKS | ATMEL_US_CHRL | ATMEL_US_NBSTOP |
@@ -2025,7 +2124,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
if (atmel_use_pdc_rx(port))
/* need to enable error interrupts */
- UART_PUT_IER(port, port->read_status_mask);
+ atmel_uart_writel(port, ATMEL_US_IER, port->read_status_mask);
/*
* Characters to ignore
@@ -2052,15 +2151,16 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
* transmitter is empty if requested by the caller, so there's
* no need to wait for it here.
*/
- imr = UART_GET_IMR(port);
- UART_PUT_IDR(port, -1);
+ imr = atmel_uart_readl(port, ATMEL_US_IMR);
+ atmel_uart_writel(port, ATMEL_US_IDR, -1);
/* disable receiver and transmitter */
- UART_PUT_CR(port, ATMEL_US_TXDIS | ATMEL_US_RXDIS);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXDIS | ATMEL_US_RXDIS);
/* mode */
if (port->rs485.flags & SER_RS485_ENABLED) {
- UART_PUT_TTGR(port, port->rs485.delay_rts_after_send);
+ atmel_uart_writel(port, ATMEL_US_TTGR,
+ port->rs485.delay_rts_after_send);
mode |= ATMEL_US_USMODE_RS485;
} else if (termios->c_cflag & CRTSCTS) {
/* RS232 with hardware handshake (RTS/CTS) */
@@ -2071,7 +2171,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
}
/* set the mode, clock divisor, parity, stop bits and data size */
- UART_PUT_MR(port, mode);
+ atmel_uart_writel(port, ATMEL_US_MR, mode);
/*
* when switching the mode, set the RTS line state according to the
@@ -2088,16 +2188,16 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
rts_state = ATMEL_US_RTSEN;
}
- UART_PUT_CR(port, rts_state);
+ atmel_uart_writel(port, ATMEL_US_CR, rts_state);
}
/* set the baud rate */
- UART_PUT_BRGR(port, quot);
- UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
- UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
+ atmel_uart_writel(port, ATMEL_US_BRGR, quot);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN | ATMEL_US_RXEN);
/* restore interrupts */
- UART_PUT_IER(port, imr);
+ atmel_uart_writel(port, ATMEL_US_IER, imr);
/* CTS flow-control and modem-status interrupts */
if (UART_ENABLE_MS(port, termios->c_cflag))
@@ -2208,18 +2308,18 @@ static int atmel_verify_port(struct uart_port *port, struct serial_struct *ser)
#ifdef CONFIG_CONSOLE_POLL
static int atmel_poll_get_char(struct uart_port *port)
{
- while (!(UART_GET_CSR(port) & ATMEL_US_RXRDY))
+ while (!(atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_RXRDY))
cpu_relax();
- return UART_GET_CHAR(port);
+ return atmel_uart_read_char(port);
}
static void atmel_poll_put_char(struct uart_port *port, unsigned char ch)
{
- while (!(UART_GET_CSR(port) & ATMEL_US_TXRDY))
+ while (!(atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXRDY))
cpu_relax();
- UART_PUT_CHAR(port, ch);
+ atmel_uart_write_char(port, ch);
}
#endif
@@ -2324,9 +2424,9 @@ struct platform_device *atmel_default_console_device; /* the serial console devi
#ifdef CONFIG_SERIAL_ATMEL_CONSOLE
static void atmel_console_putchar(struct uart_port *port, int ch)
{
- while (!(UART_GET_CSR(port) & ATMEL_US_TXRDY))
+ while (!(atmel_uart_readl(port, ATMEL_US_CSR) & ATMEL_US_TXRDY))
cpu_relax();
- UART_PUT_CHAR(port, ch);
+ atmel_uart_write_char(port, ch);
}
/*
@@ -2342,12 +2442,13 @@ static void atmel_console_write(struct console *co, const char *s, u_int count)
/*
* First, save IMR and then disable interrupts
*/
- imr = UART_GET_IMR(port);
- UART_PUT_IDR(port, ATMEL_US_RXRDY | atmel_port->tx_done_mask);
+ imr = atmel_uart_readl(port, ATMEL_US_IMR);
+ atmel_uart_writel(port, ATMEL_US_IDR,
+ ATMEL_US_RXRDY | atmel_port->tx_done_mask);
/* Store PDC transmit status and disable it */
- pdc_tx = UART_GET_PTSR(port) & ATMEL_PDC_TXTEN;
- UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
+ pdc_tx = atmel_uart_readl(port, ATMEL_PDC_PTSR) & ATMEL_PDC_TXTEN;
+ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS);
uart_console_write(port, s, count, atmel_console_putchar);
@@ -2356,15 +2457,15 @@ static void atmel_console_write(struct console *co, const char *s, u_int count)
* and restore IMR
*/
do {
- status = UART_GET_CSR(port);
+ status = atmel_uart_readl(port, ATMEL_US_CSR);
} while (!(status & ATMEL_US_TXRDY));
/* Restore PDC transmit status */
if (pdc_tx)
- UART_PUT_PTCR(port, ATMEL_PDC_TXTEN);
+ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
/* set interrupts back the way they were */
- UART_PUT_IER(port, imr);
+ atmel_uart_writel(port, ATMEL_US_IER, imr);
}
/*
@@ -2380,17 +2481,17 @@ static void __init atmel_console_get_options(struct uart_port *port, int *baud,
* If the baud rate generator isn't running, the port wasn't
* initialized by the boot loader.
*/
- quot = UART_GET_BRGR(port) & ATMEL_US_CD;
+ quot = atmel_uart_readl(port, ATMEL_US_BRGR) & ATMEL_US_CD;
if (!quot)
return;
- mr = UART_GET_MR(port) & ATMEL_US_CHRL;
+ mr = atmel_uart_readl(port, ATMEL_US_MR) & ATMEL_US_CHRL;
if (mr == ATMEL_US_CHRL_8)
*bits = 8;
else
*bits = 7;
- mr = UART_GET_MR(port) & ATMEL_US_PAR;
+ mr = atmel_uart_readl(port, ATMEL_US_MR) & ATMEL_US_PAR;
if (mr == ATMEL_US_PAR_EVEN)
*parity = 'e';
else if (mr == ATMEL_US_PAR_ODD)
@@ -2423,9 +2524,9 @@ static int __init atmel_console_setup(struct console *co, char *options)
if (ret)
return ret;
- UART_PUT_IDR(port, -1);
- UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
- UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
+ atmel_uart_writel(port, ATMEL_US_IDR, -1);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA | ATMEL_US_RSTRX);
+ atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN | ATMEL_US_RXEN);
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
@@ -2532,7 +2633,8 @@ static int atmel_serial_suspend(struct platform_device *pdev,
if (atmel_is_console_port(port) && console_suspend_enabled) {
/* Drain the TX shifter */
- while (!(UART_GET_CSR(port) & ATMEL_US_TXEMPTY))
+ while (!(atmel_uart_readl(port, ATMEL_US_CSR) &
+ ATMEL_US_TXEMPTY))
cpu_relax();
}
@@ -2599,6 +2701,48 @@ static int atmel_init_gpios(struct atmel_uart_port *p, struct device *dev)
return 0;
}
+static void atmel_serial_probe_fifos(struct atmel_uart_port *port,
+ struct platform_device *pdev)
+{
+ port->fifo_size = 0;
+ port->rts_low = 0;
+ port->rts_high = 0;
+
+ if (of_property_read_u32(pdev->dev.of_node,
+ "atmel,fifo-size",
+ &port->fifo_size))
+ return;
+
+ if (!port->fifo_size)
+ return;
+
+ if (port->fifo_size < ATMEL_MIN_FIFO_SIZE) {
+ port->fifo_size = 0;
+ dev_err(&pdev->dev, "Invalid FIFO size\n");
+ return;
+ }
+
+ /*
+ * 0 <= rts_low <= rts_high <= fifo_size
+ * Once their CTS line asserted by the remote peer, some x86 UARTs tend
+ * to flush their internal TX FIFO, commonly up to 16 data, before
+ * actually stopping to send new data. So we try to set the RTS High
+ * Threshold to a reasonably high value respecting this 16 data
+ * empirical rule when possible.
+ */
+ port->rts_high = max_t(int, port->fifo_size >> 1,
+ port->fifo_size - ATMEL_RTS_HIGH_OFFSET);
+ port->rts_low = max_t(int, port->fifo_size >> 2,
+ port->fifo_size - ATMEL_RTS_LOW_OFFSET);
+
+ dev_info(&pdev->dev, "Using FIFO (%u data)\n",
+ port->fifo_size);
+ dev_dbg(&pdev->dev, "RTS High Threshold : %2u data\n",
+ port->rts_high);
+ dev_dbg(&pdev->dev, "RTS Low Threshold : %2u data\n",
+ port->rts_low);
+}
+
static int atmel_serial_probe(struct platform_device *pdev)
{
struct atmel_uart_port *port;
@@ -2635,6 +2779,7 @@ static int atmel_serial_probe(struct platform_device *pdev)
port = &atmel_ports[ret];
port->backup_imr = 0;
port->uart.line = ret;
+ atmel_serial_probe_fifos(port, pdev);
spin_lock_init(&port->lock_suspended);
@@ -2684,8 +2829,9 @@ static int atmel_serial_probe(struct platform_device *pdev)
clk_prepare_enable(port->clk);
if (rs485_enabled) {
- UART_PUT_MR(&port->uart, ATMEL_US_USMODE_NORMAL);
- UART_PUT_CR(&port->uart, ATMEL_US_RTSEN);
+ atmel_uart_writel(&port->uart, ATMEL_US_MR,
+ ATMEL_US_USMODE_NORMAL);
+ atmel_uart_writel(&port->uart, ATMEL_US_CR, ATMEL_US_RTSEN);
}
/*