#include "samsung.h"
#if defined(CONFIG_SERIAL_SAMSUNG_DEBUG) && \
- defined(CONFIG_DEBUG_LL) && \
!defined(MODULE)
extern void printascii(const char *);
if (ourport->tx_mode != S3C24XX_TX_DMA)
enable_tx_dma(ourport);
- while (xmit->tail & (dma_get_cache_alignment() - 1)) {
- if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
- return 0;
- wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
- xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
- port->icount.tx++;
- count--;
- }
-
dma->tx_size = count & ~(dma_get_cache_alignment() - 1);
dma->tx_transfer_addr = dma->tx_addr + xmit->tail;
return;
}
- if (!ourport->dma || !ourport->dma->tx_chan || count < port->fifosize)
+ if (!ourport->dma || !ourport->dma->tx_chan ||
+ count < ourport->min_dma_size ||
+ xmit->tail & (dma_get_cache_alignment() - 1))
s3c24xx_serial_start_tx_pio(ourport);
else
s3c24xx_serial_start_tx_dma(ourport, count);
}
-void s3c24xx_serial_start_tx(struct uart_port *port)
+static void s3c24xx_serial_start_tx(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
struct circ_buf *xmit = &port->state->xmit;
}
}
-static int s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port *ourport,
- unsigned long ufstat);
-
-static void uart_rx_drain_fifo(struct s3c24xx_uart_port *ourport)
-{
- struct uart_port *port = &ourport->port;
- struct tty_port *tty = &port->state->port;
- unsigned int ch, ufstat;
- unsigned int count;
-
- ufstat = rd_regl(port, S3C2410_UFSTAT);
- count = s3c24xx_serial_rx_fifocnt(ourport, ufstat);
-
- if (!count)
- return;
-
- while (count-- > 0) {
- ch = rd_regb(port, S3C2410_URXH);
-
- ourport->port.icount.rx++;
- tty_insert_flip_char(tty, ch, TTY_NORMAL);
- }
-
- tty_flip_buffer_push(tty);
-}
-
static void s3c24xx_serial_stop_rx(struct uart_port *port)
{
struct s3c24xx_uart_port *ourport = to_ourport(port);
ourport->rx_mode = S3C24XX_RX_PIO;
}
-static irqreturn_t s3c24xx_serial_rx_chars_dma(int irq, void *dev_id)
+static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport);
+
+static irqreturn_t s3c24xx_serial_rx_chars_dma(void *dev_id)
{
unsigned int utrstat, ufstat, received;
struct s3c24xx_uart_port *ourport = dev_id;
enable_rx_pio(ourport);
}
- uart_rx_drain_fifo(ourport);
+ s3c24xx_serial_rx_drain_fifo(ourport);
if (tty) {
tty_flip_buffer_push(t);
return IRQ_HANDLED;
}
-static irqreturn_t s3c24xx_serial_rx_chars_pio(int irq, void *dev_id)
+static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport)
{
- struct s3c24xx_uart_port *ourport = dev_id;
struct uart_port *port = &ourport->port;
unsigned int ufcon, ch, flag, ufstat, uerstat;
- unsigned long flags;
int max_count = port->fifosize;
- spin_lock_irqsave(&port->lock, flags);
-
while (max_count-- > 0) {
ufcon = rd_regl(port, S3C2410_UFCON);
ufstat = rd_regl(port, S3C2410_UFSTAT);
ufcon |= S3C2410_UFCON_RESETRX;
wr_regl(port, S3C2410_UFCON, ufcon);
rx_enabled(port) = 1;
- spin_unlock_irqrestore(&port->lock,
- flags);
- goto out;
+ return;
}
continue;
}
dbg("break!\n");
port->icount.brk++;
if (uart_handle_break(port))
- goto ignore_char;
+ continue; /* Ignore character */
}
if (uerstat & S3C2410_UERSTAT_FRAME)
}
if (uart_handle_sysrq_char(port, ch))
- goto ignore_char;
+ continue; /* Ignore character */
uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,
ch, flag);
-
-ignore_char:
- continue;
}
- spin_unlock_irqrestore(&port->lock, flags);
tty_flip_buffer_push(&port->state->port);
+}
+
+static irqreturn_t s3c24xx_serial_rx_chars_pio(void *dev_id)
+{
+ struct s3c24xx_uart_port *ourport = dev_id;
+ struct uart_port *port = &ourport->port;
+ unsigned long flags;
+
+ spin_lock_irqsave(&port->lock, flags);
+ s3c24xx_serial_rx_drain_fifo(ourport);
+ spin_unlock_irqrestore(&port->lock, flags);
-out:
return IRQ_HANDLED;
}
struct s3c24xx_uart_port *ourport = dev_id;
if (ourport->dma && ourport->dma->rx_chan)
- return s3c24xx_serial_rx_chars_dma(irq, dev_id);
- return s3c24xx_serial_rx_chars_pio(irq, dev_id);
+ return s3c24xx_serial_rx_chars_dma(dev_id);
+ return s3c24xx_serial_rx_chars_pio(dev_id);
}
static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
struct uart_port *port = &ourport->port;
struct circ_buf *xmit = &port->state->xmit;
unsigned long flags;
- int count;
+ int count, dma_count = 0;
spin_lock_irqsave(&port->lock, flags);
count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
- if (ourport->dma && ourport->dma->tx_chan && count >= port->fifosize) {
- s3c24xx_serial_start_tx_dma(ourport, count);
- goto out;
+ if (ourport->dma && ourport->dma->tx_chan &&
+ count >= ourport->min_dma_size) {
+ int align = dma_get_cache_alignment() -
+ (xmit->tail & (dma_get_cache_alignment() - 1));
+ if (count-align >= ourport->min_dma_size) {
+ dma_count = count-align;
+ count = align;
+ }
}
if (port->x_char) {
/* try and drain the buffer... */
- count = port->fifosize;
- while (!uart_circ_empty(xmit) && count-- > 0) {
+ if (count > port->fifosize) {
+ count = port->fifosize;
+ dma_count = 0;
+ }
+
+ while (!uart_circ_empty(xmit) && count > 0) {
if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
break;
wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
+ count--;
+ }
+
+ if (!count && dma_count) {
+ s3c24xx_serial_start_tx_dma(ourport, dma_count);
+ goto out;
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) {
/* check to see if we need to change clock source */
if (ourport->baudclk != clk) {
+ clk_prepare_enable(clk);
+
s3c24xx_serial_setsource(port, clk_sel);
if (!IS_ERR(ourport->baudclk)) {
ourport->baudclk = ERR_PTR(-EINVAL);
}
- clk_prepare_enable(clk);
-
ourport->baudclk = clk;
ourport->baudclk_rate = clk ? clk_get_rate(clk) : 0;
}
return -ENODEV;
if (port->mapbase != 0)
- return 0;
+ return -EINVAL;
/* setup info for port */
port->dev = &platdev->dev;
ourport->dma = devm_kzalloc(port->dev,
sizeof(*ourport->dma),
GFP_KERNEL);
- if (!ourport->dma)
- return -ENOMEM;
+ if (!ourport->dma) {
+ ret = -ENOMEM;
+ goto err;
+ }
}
ourport->clk = clk_get(&platdev->dev, "uart");
if (IS_ERR(ourport->clk)) {
pr_err("%s: Controller clock not found\n",
dev_name(&platdev->dev));
- return PTR_ERR(ourport->clk);
+ ret = PTR_ERR(ourport->clk);
+ goto err;
}
ret = clk_prepare_enable(ourport->clk);
if (ret) {
pr_err("uart: clock failed to prepare+enable: %d\n", ret);
clk_put(ourport->clk);
- return ret;
+ goto err;
}
/* Keep all interrupts masked and cleared */
/* reset the fifos (and setup the uart) */
s3c24xx_serial_resetport(port, cfg);
+
return 0;
+
+err:
+ port->mapbase = 0;
+ return ret;
}
/* Device driver serial port probe */
else if (ourport->info->fifosize)
ourport->port.fifosize = ourport->info->fifosize;
+ /*
+ * DMA transfers must be aligned at least to cache line size,
+ * so find minimal transfer size suitable for DMA mode
+ */
+ ourport->min_dma_size = max_t(int, ourport->port.fifosize,
+ dma_get_cache_alignment());
+
probe_index++;
dbg("%s: initialising port %p...\n", __func__, ourport);
#define EXYNOS5433_SERIAL_DRV_DATA (kernel_ulong_t)NULL
#endif
-static struct platform_device_id s3c24xx_serial_driver_ids[] = {
+static const struct platform_device_id s3c24xx_serial_driver_ids[] = {
{
.name = "s3c2410-uart",
.driver_data = S3C2410_SERIAL_DRV_DATA,
Code Review / kvmfornfv.git / blobdiff