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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-01-20 14:01:31 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-01-20 14:01:31 -0300
commitb4b7ff4b08e691656c9d77c758fc355833128ac0 (patch)
tree82fcb00e6b918026dc9f2d1f05ed8eee83874cc0 /drivers/tty/serial/msm_serial.c
parent35acfa0fc609f2a2cd95cef4a6a9c3a5c38f1778 (diff)
Linux-libre 4.4-gnupck-4.4-gnu
Diffstat (limited to 'drivers/tty/serial/msm_serial.c')
-rw-r--r--drivers/tty/serial/msm_serial.c622
1 files changed, 570 insertions, 52 deletions
diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
index b73889c8e..dcde95547 100644
--- a/drivers/tty/serial/msm_serial.c
+++ b/drivers/tty/serial/msm_serial.c
@@ -20,6 +20,8 @@
#endif
#include <linux/atomic.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
#include <linux/hrtimer.h>
#include <linux/module.h>
#include <linux/io.h>
@@ -31,6 +33,7 @@
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
#include <linux/serial.h>
+#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
@@ -39,6 +42,11 @@
#include "msm_serial.h"
+#define UARTDM_BURST_SIZE 16 /* in bytes */
+#define UARTDM_TX_AIGN(x) ((x) & ~0x3) /* valid for > 1p3 */
+#define UARTDM_TX_MAX 256 /* in bytes, valid for <= 1p3 */
+#define UARTDM_RX_SIZE (UART_XMIT_SIZE / 4)
+
enum {
UARTDM_1P1 = 1,
UARTDM_1P2,
@@ -46,6 +54,17 @@ enum {
UARTDM_1P4,
};
+struct msm_dma {
+ struct dma_chan *chan;
+ enum dma_data_direction dir;
+ dma_addr_t phys;
+ unsigned char *virt;
+ dma_cookie_t cookie;
+ u32 enable_bit;
+ unsigned int count;
+ struct dma_async_tx_descriptor *desc;
+};
+
struct msm_port {
struct uart_port uart;
char name[16];
@@ -55,9 +74,153 @@ struct msm_port {
int is_uartdm;
unsigned int old_snap_state;
bool break_detected;
+ struct msm_dma tx_dma;
+ struct msm_dma rx_dma;
};
-static inline void wait_for_xmitr(struct uart_port *port)
+static void msm_handle_tx(struct uart_port *port);
+static void msm_start_rx_dma(struct msm_port *msm_port);
+
+void msm_stop_dma(struct uart_port *port, struct msm_dma *dma)
+{
+ struct device *dev = port->dev;
+ unsigned int mapped;
+ u32 val;
+
+ mapped = dma->count;
+ dma->count = 0;
+
+ dmaengine_terminate_all(dma->chan);
+
+ /*
+ * DMA Stall happens if enqueue and flush command happens concurrently.
+ * For example before changing the baud rate/protocol configuration and
+ * sending flush command to ADM, disable the channel of UARTDM.
+ * Note: should not reset the receiver here immediately as it is not
+ * suggested to do disable/reset or reset/disable at the same time.
+ */
+ val = msm_read(port, UARTDM_DMEN);
+ val &= ~dma->enable_bit;
+ msm_write(port, val, UARTDM_DMEN);
+
+ if (mapped)
+ dma_unmap_single(dev, dma->phys, mapped, dma->dir);
+}
+
+static void msm_release_dma(struct msm_port *msm_port)
+{
+ struct msm_dma *dma;
+
+ dma = &msm_port->tx_dma;
+ if (dma->chan) {
+ msm_stop_dma(&msm_port->uart, dma);
+ dma_release_channel(dma->chan);
+ }
+
+ memset(dma, 0, sizeof(*dma));
+
+ dma = &msm_port->rx_dma;
+ if (dma->chan) {
+ msm_stop_dma(&msm_port->uart, dma);
+ dma_release_channel(dma->chan);
+ kfree(dma->virt);
+ }
+
+ memset(dma, 0, sizeof(*dma));
+}
+
+static void msm_request_tx_dma(struct msm_port *msm_port, resource_size_t base)
+{
+ struct device *dev = msm_port->uart.dev;
+ struct dma_slave_config conf;
+ struct msm_dma *dma;
+ u32 crci = 0;
+ int ret;
+
+ dma = &msm_port->tx_dma;
+
+ /* allocate DMA resources, if available */
+ dma->chan = dma_request_slave_channel_reason(dev, "tx");
+ if (IS_ERR(dma->chan))
+ goto no_tx;
+
+ of_property_read_u32(dev->of_node, "qcom,tx-crci", &crci);
+
+ memset(&conf, 0, sizeof(conf));
+ conf.direction = DMA_MEM_TO_DEV;
+ conf.device_fc = true;
+ conf.dst_addr = base + UARTDM_TF;
+ conf.dst_maxburst = UARTDM_BURST_SIZE;
+ conf.slave_id = crci;
+
+ ret = dmaengine_slave_config(dma->chan, &conf);
+ if (ret)
+ goto rel_tx;
+
+ dma->dir = DMA_TO_DEVICE;
+
+ if (msm_port->is_uartdm < UARTDM_1P4)
+ dma->enable_bit = UARTDM_DMEN_TX_DM_ENABLE;
+ else
+ dma->enable_bit = UARTDM_DMEN_TX_BAM_ENABLE;
+
+ return;
+
+rel_tx:
+ dma_release_channel(dma->chan);
+no_tx:
+ memset(dma, 0, sizeof(*dma));
+}
+
+static void msm_request_rx_dma(struct msm_port *msm_port, resource_size_t base)
+{
+ struct device *dev = msm_port->uart.dev;
+ struct dma_slave_config conf;
+ struct msm_dma *dma;
+ u32 crci = 0;
+ int ret;
+
+ dma = &msm_port->rx_dma;
+
+ /* allocate DMA resources, if available */
+ dma->chan = dma_request_slave_channel_reason(dev, "rx");
+ if (IS_ERR(dma->chan))
+ goto no_rx;
+
+ of_property_read_u32(dev->of_node, "qcom,rx-crci", &crci);
+
+ dma->virt = kzalloc(UARTDM_RX_SIZE, GFP_KERNEL);
+ if (!dma->virt)
+ goto rel_rx;
+
+ memset(&conf, 0, sizeof(conf));
+ conf.direction = DMA_DEV_TO_MEM;
+ conf.device_fc = true;
+ conf.src_addr = base + UARTDM_RF;
+ conf.src_maxburst = UARTDM_BURST_SIZE;
+ conf.slave_id = crci;
+
+ ret = dmaengine_slave_config(dma->chan, &conf);
+ if (ret)
+ goto err;
+
+ dma->dir = DMA_FROM_DEVICE;
+
+ if (msm_port->is_uartdm < UARTDM_1P4)
+ dma->enable_bit = UARTDM_DMEN_RX_DM_ENABLE;
+ else
+ dma->enable_bit = UARTDM_DMEN_RX_BAM_ENABLE;
+
+ return;
+err:
+ kfree(dma->virt);
+rel_rx:
+ dma_release_channel(dma->chan);
+no_rx:
+ memset(dma, 0, sizeof(*dma));
+}
+
+static inline void msm_wait_for_xmitr(struct uart_port *port)
{
while (!(msm_read(port, UART_SR) & UART_SR_TX_EMPTY)) {
if (msm_read(port, UART_ISR) & UART_ISR_TX_READY)
@@ -78,17 +241,277 @@ static void msm_stop_tx(struct uart_port *port)
static void msm_start_tx(struct uart_port *port)
{
struct msm_port *msm_port = UART_TO_MSM(port);
+ struct msm_dma *dma = &msm_port->tx_dma;
+
+ /* Already started in DMA mode */
+ if (dma->count)
+ return;
+
+ msm_port->imr |= UART_IMR_TXLEV;
+ msm_write(port, msm_port->imr, UART_IMR);
+}
+
+static void msm_reset_dm_count(struct uart_port *port, int count)
+{
+ msm_wait_for_xmitr(port);
+ msm_write(port, count, UARTDM_NCF_TX);
+ msm_read(port, UARTDM_NCF_TX);
+}
+
+static void msm_complete_tx_dma(void *args)
+{
+ struct msm_port *msm_port = args;
+ struct uart_port *port = &msm_port->uart;
+ struct circ_buf *xmit = &port->state->xmit;
+ struct msm_dma *dma = &msm_port->tx_dma;
+ struct dma_tx_state state;
+ enum dma_status status;
+ unsigned long flags;
+ unsigned int count;
+ u32 val;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ /* Already stopped */
+ if (!dma->count)
+ goto done;
+
+ status = dmaengine_tx_status(dma->chan, dma->cookie, &state);
+
+ dma_unmap_single(port->dev, dma->phys, dma->count, dma->dir);
+ val = msm_read(port, UARTDM_DMEN);
+ val &= ~dma->enable_bit;
+ msm_write(port, val, UARTDM_DMEN);
+
+ if (msm_port->is_uartdm > UARTDM_1P3) {
+ msm_write(port, UART_CR_CMD_RESET_TX, UART_CR);
+ msm_write(port, UART_CR_TX_ENABLE, UART_CR);
+ }
+
+ count = dma->count - state.residue;
+ port->icount.tx += count;
+ dma->count = 0;
+
+ xmit->tail += count;
+ xmit->tail &= UART_XMIT_SIZE - 1;
+
+ /* Restore "Tx FIFO below watermark" interrupt */
msm_port->imr |= UART_IMR_TXLEV;
msm_write(port, msm_port->imr, UART_IMR);
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+
+ msm_handle_tx(port);
+done:
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static int msm_handle_tx_dma(struct msm_port *msm_port, unsigned int count)
+{
+ struct circ_buf *xmit = &msm_port->uart.state->xmit;
+ struct uart_port *port = &msm_port->uart;
+ struct msm_dma *dma = &msm_port->tx_dma;
+ void *cpu_addr;
+ int ret;
+ u32 val;
+
+ cpu_addr = &xmit->buf[xmit->tail];
+
+ dma->phys = dma_map_single(port->dev, cpu_addr, count, dma->dir);
+ ret = dma_mapping_error(port->dev, dma->phys);
+ if (ret)
+ return ret;
+
+ dma->desc = dmaengine_prep_slave_single(dma->chan, dma->phys,
+ count, DMA_MEM_TO_DEV,
+ DMA_PREP_INTERRUPT |
+ DMA_PREP_FENCE);
+ if (!dma->desc) {
+ ret = -EIO;
+ goto unmap;
+ }
+
+ dma->desc->callback = msm_complete_tx_dma;
+ dma->desc->callback_param = msm_port;
+
+ dma->cookie = dmaengine_submit(dma->desc);
+ ret = dma_submit_error(dma->cookie);
+ if (ret)
+ goto unmap;
+
+ /*
+ * Using DMA complete for Tx FIFO reload, no need for
+ * "Tx FIFO below watermark" one, disable it
+ */
+ msm_port->imr &= ~UART_IMR_TXLEV;
+ msm_write(port, msm_port->imr, UART_IMR);
+
+ dma->count = count;
+
+ val = msm_read(port, UARTDM_DMEN);
+ val |= dma->enable_bit;
+
+ if (msm_port->is_uartdm < UARTDM_1P4)
+ msm_write(port, val, UARTDM_DMEN);
+
+ msm_reset_dm_count(port, count);
+
+ if (msm_port->is_uartdm > UARTDM_1P3)
+ msm_write(port, val, UARTDM_DMEN);
+
+ dma_async_issue_pending(dma->chan);
+ return 0;
+unmap:
+ dma_unmap_single(port->dev, dma->phys, count, dma->dir);
+ return ret;
+}
+
+static void msm_complete_rx_dma(void *args)
+{
+ struct msm_port *msm_port = args;
+ struct uart_port *port = &msm_port->uart;
+ struct tty_port *tport = &port->state->port;
+ struct msm_dma *dma = &msm_port->rx_dma;
+ int count = 0, i, sysrq;
+ unsigned long flags;
+ u32 val;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ /* Already stopped */
+ if (!dma->count)
+ goto done;
+
+ val = msm_read(port, UARTDM_DMEN);
+ val &= ~dma->enable_bit;
+ msm_write(port, val, UARTDM_DMEN);
+
+ /* Restore interrupts */
+ msm_port->imr |= UART_IMR_RXLEV | UART_IMR_RXSTALE;
+ msm_write(port, msm_port->imr, UART_IMR);
+
+ if (msm_read(port, UART_SR) & UART_SR_OVERRUN) {
+ port->icount.overrun++;
+ tty_insert_flip_char(tport, 0, TTY_OVERRUN);
+ msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
+ }
+
+ count = msm_read(port, UARTDM_RX_TOTAL_SNAP);
+
+ port->icount.rx += count;
+
+ dma->count = 0;
+
+ dma_unmap_single(port->dev, dma->phys, UARTDM_RX_SIZE, dma->dir);
+
+ for (i = 0; i < count; i++) {
+ char flag = TTY_NORMAL;
+
+ if (msm_port->break_detected && dma->virt[i] == 0) {
+ port->icount.brk++;
+ flag = TTY_BREAK;
+ msm_port->break_detected = false;
+ if (uart_handle_break(port))
+ continue;
+ }
+
+ if (!(port->read_status_mask & UART_SR_RX_BREAK))
+ flag = TTY_NORMAL;
+
+ spin_unlock_irqrestore(&port->lock, flags);
+ sysrq = uart_handle_sysrq_char(port, dma->virt[i]);
+ spin_lock_irqsave(&port->lock, flags);
+ if (!sysrq)
+ tty_insert_flip_char(tport, dma->virt[i], flag);
+ }
+
+ msm_start_rx_dma(msm_port);
+done:
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ if (count)
+ tty_flip_buffer_push(tport);
+}
+
+static void msm_start_rx_dma(struct msm_port *msm_port)
+{
+ struct msm_dma *dma = &msm_port->rx_dma;
+ struct uart_port *uart = &msm_port->uart;
+ u32 val;
+ int ret;
+
+ if (!dma->chan)
+ return;
+
+ dma->phys = dma_map_single(uart->dev, dma->virt,
+ UARTDM_RX_SIZE, dma->dir);
+ ret = dma_mapping_error(uart->dev, dma->phys);
+ if (ret)
+ return;
+
+ dma->desc = dmaengine_prep_slave_single(dma->chan, dma->phys,
+ UARTDM_RX_SIZE, DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT);
+ if (!dma->desc)
+ goto unmap;
+
+ dma->desc->callback = msm_complete_rx_dma;
+ dma->desc->callback_param = msm_port;
+
+ dma->cookie = dmaengine_submit(dma->desc);
+ ret = dma_submit_error(dma->cookie);
+ if (ret)
+ goto unmap;
+ /*
+ * Using DMA for FIFO off-load, no need for "Rx FIFO over
+ * watermark" or "stale" interrupts, disable them
+ */
+ msm_port->imr &= ~(UART_IMR_RXLEV | UART_IMR_RXSTALE);
+
+ /*
+ * Well, when DMA is ADM3 engine(implied by <= UARTDM v1.3),
+ * we need RXSTALE to flush input DMA fifo to memory
+ */
+ if (msm_port->is_uartdm < UARTDM_1P4)
+ msm_port->imr |= UART_IMR_RXSTALE;
+
+ msm_write(uart, msm_port->imr, UART_IMR);
+
+ dma->count = UARTDM_RX_SIZE;
+
+ dma_async_issue_pending(dma->chan);
+
+ msm_write(uart, UART_CR_CMD_RESET_STALE_INT, UART_CR);
+ msm_write(uart, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR);
+
+ val = msm_read(uart, UARTDM_DMEN);
+ val |= dma->enable_bit;
+
+ if (msm_port->is_uartdm < UARTDM_1P4)
+ msm_write(uart, val, UARTDM_DMEN);
+
+ msm_write(uart, UARTDM_RX_SIZE, UARTDM_DMRX);
+
+ if (msm_port->is_uartdm > UARTDM_1P3)
+ msm_write(uart, val, UARTDM_DMEN);
+
+ return;
+unmap:
+ dma_unmap_single(uart->dev, dma->phys, UARTDM_RX_SIZE, dma->dir);
}
static void msm_stop_rx(struct uart_port *port)
{
struct msm_port *msm_port = UART_TO_MSM(port);
+ struct msm_dma *dma = &msm_port->rx_dma;
msm_port->imr &= ~(UART_IMR_RXLEV | UART_IMR_RXSTALE);
msm_write(port, msm_port->imr, UART_IMR);
+
+ if (dma->chan)
+ msm_stop_dma(port, dma);
}
static void msm_enable_ms(struct uart_port *port)
@@ -99,7 +522,7 @@ static void msm_enable_ms(struct uart_port *port)
msm_write(port, msm_port->imr, UART_IMR);
}
-static void handle_rx_dm(struct uart_port *port, unsigned int misr)
+static void msm_handle_rx_dm(struct uart_port *port, unsigned int misr)
{
struct tty_port *tport = &port->state->port;
unsigned int sr;
@@ -169,9 +592,12 @@ static void handle_rx_dm(struct uart_port *port, unsigned int misr)
msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR);
msm_write(port, 0xFFFFFF, UARTDM_DMRX);
msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR);
+
+ /* Try to use DMA */
+ msm_start_rx_dma(msm_port);
}
-static void handle_rx(struct uart_port *port)
+static void msm_handle_rx(struct uart_port *port)
{
struct tty_port *tport = &port->state->port;
unsigned int sr;
@@ -224,18 +650,11 @@ static void handle_rx(struct uart_port *port)
spin_lock(&port->lock);
}
-static void reset_dm_count(struct uart_port *port, int count)
-{
- wait_for_xmitr(port);
- msm_write(port, count, UARTDM_NCF_TX);
- msm_read(port, UARTDM_NCF_TX);
-}
-
-static void handle_tx(struct uart_port *port)
+static void msm_handle_tx_pio(struct uart_port *port, unsigned int tx_count)
{
struct circ_buf *xmit = &port->state->xmit;
struct msm_port *msm_port = UART_TO_MSM(port);
- unsigned int tx_count, num_chars;
+ unsigned int num_chars;
unsigned int tf_pointer = 0;
void __iomem *tf;
@@ -244,20 +663,8 @@ static void handle_tx(struct uart_port *port)
else
tf = port->membase + UART_TF;
- tx_count = uart_circ_chars_pending(xmit);
- tx_count = min3(tx_count, (unsigned int)UART_XMIT_SIZE - xmit->tail,
- port->fifosize);
-
- if (port->x_char) {
- if (msm_port->is_uartdm)
- reset_dm_count(port, tx_count + 1);
-
- iowrite8_rep(tf, &port->x_char, 1);
- port->icount.tx++;
- port->x_char = 0;
- } else if (tx_count && msm_port->is_uartdm) {
- reset_dm_count(port, tx_count);
- }
+ if (tx_count && msm_port->is_uartdm)
+ msm_reset_dm_count(port, tx_count);
while (tf_pointer < tx_count) {
int i;
@@ -290,20 +697,76 @@ static void handle_tx(struct uart_port *port)
uart_write_wakeup(port);
}
-static void handle_delta_cts(struct uart_port *port)
+static void msm_handle_tx(struct uart_port *port)
+{
+ struct msm_port *msm_port = UART_TO_MSM(port);
+ struct circ_buf *xmit = &msm_port->uart.state->xmit;
+ struct msm_dma *dma = &msm_port->tx_dma;
+ unsigned int pio_count, dma_count, dma_min;
+ void __iomem *tf;
+ int err = 0;
+
+ if (port->x_char) {
+ if (msm_port->is_uartdm)
+ tf = port->membase + UARTDM_TF;
+ else
+ tf = port->membase + UART_TF;
+
+ if (msm_port->is_uartdm)
+ msm_reset_dm_count(port, 1);
+
+ iowrite8_rep(tf, &port->x_char, 1);
+ port->icount.tx++;
+ port->x_char = 0;
+ return;
+ }
+
+ if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+ msm_stop_tx(port);
+ return;
+ }
+
+ pio_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
+ dma_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
+
+ dma_min = 1; /* Always DMA */
+ if (msm_port->is_uartdm > UARTDM_1P3) {
+ dma_count = UARTDM_TX_AIGN(dma_count);
+ dma_min = UARTDM_BURST_SIZE;
+ } else {
+ if (dma_count > UARTDM_TX_MAX)
+ dma_count = UARTDM_TX_MAX;
+ }
+
+ if (pio_count > port->fifosize)
+ pio_count = port->fifosize;
+
+ if (!dma->chan || dma_count < dma_min)
+ msm_handle_tx_pio(port, pio_count);
+ else
+ err = msm_handle_tx_dma(msm_port, dma_count);
+
+ if (err) /* fall back to PIO mode */
+ msm_handle_tx_pio(port, pio_count);
+}
+
+static void msm_handle_delta_cts(struct uart_port *port)
{
msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
port->icount.cts++;
wake_up_interruptible(&port->state->port.delta_msr_wait);
}
-static irqreturn_t msm_irq(int irq, void *dev_id)
+static irqreturn_t msm_uart_irq(int irq, void *dev_id)
{
struct uart_port *port = dev_id;
struct msm_port *msm_port = UART_TO_MSM(port);
+ struct msm_dma *dma = &msm_port->rx_dma;
+ unsigned long flags;
unsigned int misr;
+ u32 val;
- spin_lock(&port->lock);
+ spin_lock_irqsave(&port->lock, flags);
misr = msm_read(port, UART_MISR);
msm_write(port, 0, UART_IMR); /* disable interrupt */
@@ -313,18 +776,29 @@ static irqreturn_t msm_irq(int irq, void *dev_id)
}
if (misr & (UART_IMR_RXLEV | UART_IMR_RXSTALE)) {
- if (msm_port->is_uartdm)
- handle_rx_dm(port, misr);
- else
- handle_rx(port);
+ if (dma->count) {
+ val = UART_CR_CMD_STALE_EVENT_DISABLE;
+ msm_write(port, val, UART_CR);
+ val = UART_CR_CMD_RESET_STALE_INT;
+ msm_write(port, val, UART_CR);
+ /*
+ * Flush DMA input fifo to memory, this will also
+ * trigger DMA RX completion
+ */
+ dmaengine_terminate_all(dma->chan);
+ } else if (msm_port->is_uartdm) {
+ msm_handle_rx_dm(port, misr);
+ } else {
+ msm_handle_rx(port);
+ }
}
if (misr & UART_IMR_TXLEV)
- handle_tx(port);
+ msm_handle_tx(port);
if (misr & UART_IMR_DELTA_CTS)
- handle_delta_cts(port);
+ msm_handle_delta_cts(port);
msm_write(port, msm_port->imr, UART_IMR); /* restore interrupt */
- spin_unlock(&port->lock);
+ spin_unlock_irqrestore(&port->lock, flags);
return IRQ_HANDLED;
}
@@ -408,6 +882,7 @@ msm_find_best_baud(struct uart_port *port, unsigned int baud)
{ 3, 0xdd, 8 },
{ 2, 0xee, 16 },
{ 1, 0xff, 31 },
+ { 0, 0xff, 31 },
};
divisor = uart_get_divisor(port, baud);
@@ -419,21 +894,41 @@ msm_find_best_baud(struct uart_port *port, unsigned int baud)
return entry; /* Default to smallest divider */
}
-static int msm_set_baud_rate(struct uart_port *port, unsigned int baud)
+static int msm_set_baud_rate(struct uart_port *port, unsigned int baud,
+ unsigned long *saved_flags)
{
- unsigned int rxstale, watermark;
+ unsigned int rxstale, watermark, mask;
struct msm_port *msm_port = UART_TO_MSM(port);
const struct msm_baud_map *entry;
+ unsigned long flags;
entry = msm_find_best_baud(port, baud);
msm_write(port, entry->code, UART_CSR);
+ if (baud > 460800)
+ port->uartclk = baud * 16;
+
+ flags = *saved_flags;
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ clk_set_rate(msm_port->clk, port->uartclk);
+
+ spin_lock_irqsave(&port->lock, flags);
+ *saved_flags = flags;
+
/* RX stale watermark */
rxstale = entry->rxstale;
watermark = UART_IPR_STALE_LSB & rxstale;
- watermark |= UART_IPR_RXSTALE_LAST;
- watermark |= UART_IPR_STALE_TIMEOUT_MSB & (rxstale << 2);
+ if (msm_port->is_uartdm) {
+ mask = UART_DM_IPR_STALE_TIMEOUT_MSB;
+ } else {
+ watermark |= UART_IPR_RXSTALE_LAST;
+ mask = UART_IPR_STALE_TIMEOUT_MSB;
+ }
+
+ watermark |= mask & (rxstale << 2);
+
msm_write(port, watermark, UART_IPR);
/* set RX watermark */
@@ -476,13 +971,13 @@ static void msm_init_clock(struct uart_port *port)
static int msm_startup(struct uart_port *port)
{
struct msm_port *msm_port = UART_TO_MSM(port);
- unsigned int data, rfr_level;
+ unsigned int data, rfr_level, mask;
int ret;
snprintf(msm_port->name, sizeof(msm_port->name),
"msm_serial%d", port->line);
- ret = request_irq(port->irq, msm_irq, IRQF_TRIGGER_HIGH,
+ ret = request_irq(port->irq, msm_uart_irq, IRQF_TRIGGER_HIGH,
msm_port->name, port);
if (unlikely(ret))
return ret;
@@ -496,11 +991,23 @@ static int msm_startup(struct uart_port *port)
/* set automatic RFR level */
data = msm_read(port, UART_MR1);
- data &= ~UART_MR1_AUTO_RFR_LEVEL1;
+
+ if (msm_port->is_uartdm)
+ mask = UART_DM_MR1_AUTO_RFR_LEVEL1;
+ else
+ mask = UART_MR1_AUTO_RFR_LEVEL1;
+
+ data &= ~mask;
data &= ~UART_MR1_AUTO_RFR_LEVEL0;
- data |= UART_MR1_AUTO_RFR_LEVEL1 & (rfr_level << 2);
+ data |= mask & (rfr_level << 2);
data |= UART_MR1_AUTO_RFR_LEVEL0 & rfr_level;
msm_write(port, data, UART_MR1);
+
+ if (msm_port->is_uartdm) {
+ msm_request_tx_dma(msm_port, msm_port->uart.mapbase);
+ msm_request_rx_dma(msm_port, msm_port->uart.mapbase);
+ }
+
return 0;
}
@@ -511,6 +1018,9 @@ static void msm_shutdown(struct uart_port *port)
msm_port->imr = 0;
msm_write(port, 0, UART_IMR); /* disable interrupts */
+ if (msm_port->is_uartdm)
+ msm_release_dma(msm_port);
+
clk_disable_unprepare(msm_port->clk);
free_irq(port->irq, port);
@@ -519,14 +1029,19 @@ static void msm_shutdown(struct uart_port *port)
static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
+ struct msm_port *msm_port = UART_TO_MSM(port);
+ struct msm_dma *dma = &msm_port->rx_dma;
unsigned long flags;
unsigned int baud, mr;
spin_lock_irqsave(&port->lock, flags);
+ if (dma->chan) /* Terminate if any */
+ msm_stop_dma(port, dma);
+
/* calculate and set baud rate */
- baud = uart_get_baud_rate(port, termios, old, 300, 115200);
- baud = msm_set_baud_rate(port, baud);
+ baud = uart_get_baud_rate(port, termios, old, 300, 4000000);
+ baud = msm_set_baud_rate(port, baud, &flags);
if (tty_termios_baud_rate(termios))
tty_termios_encode_baud_rate(termios, baud, baud);
@@ -588,6 +1103,9 @@ static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
uart_update_timeout(port, termios->c_cflag, baud);
+ /* Try to use DMA */
+ msm_start_rx_dma(msm_port);
+
spin_unlock_irqrestore(&port->lock, flags);
}
@@ -765,7 +1283,7 @@ static void msm_poll_put_char(struct uart_port *port, unsigned char c)
msm_write(port, 0, UART_IMR);
if (msm_port->is_uartdm)
- reset_dm_count(port, 1);
+ msm_reset_dm_count(port, 1);
/* Wait until FIFO is empty */
while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
@@ -839,7 +1357,7 @@ static struct msm_port msm_uart_ports[] = {
#define UART_NR ARRAY_SIZE(msm_uart_ports)
-static inline struct uart_port *get_port_from_line(unsigned int line)
+static inline struct uart_port *msm_get_port_from_line(unsigned int line)
{
return &msm_uart_ports[line].uart;
}
@@ -866,7 +1384,7 @@ static void __msm_console_write(struct uart_port *port, const char *s,
spin_lock(&port->lock);
if (is_uartdm)
- reset_dm_count(port, count);
+ msm_reset_dm_count(port, count);
i = 0;
while (i < count) {
@@ -911,7 +1429,7 @@ static void msm_console_write(struct console *co, const char *s,
BUG_ON(co->index < 0 || co->index >= UART_NR);
- port = get_port_from_line(co->index);
+ port = msm_get_port_from_line(co->index);
msm_port = UART_TO_MSM(port);
__msm_console_write(port, s, count, msm_port->is_uartdm);
@@ -928,7 +1446,7 @@ static int __init msm_console_setup(struct console *co, char *options)
if (unlikely(co->index >= UART_NR || co->index < 0))
return -ENXIO;
- port = get_port_from_line(co->index);
+ port = msm_get_port_from_line(co->index);
if (unlikely(!port->membase))
return -ENXIO;
@@ -1043,7 +1561,7 @@ static int msm_serial_probe(struct platform_device *pdev)
dev_info(&pdev->dev, "msm_serial: detected port #%d\n", line);
- port = get_port_from_line(line);
+ port = msm_get_port_from_line(line);
port->dev = &pdev->dev;
msm_port = UART_TO_MSM(port);