diff options
| author | Sonic Zhang <sonic.zhang@analog.com> | 2008-02-25 10:16:50 +0300 |
|---|---|---|
| committer | Bryan Wu <cooloney@kernel.org> | 2008-02-25 10:16:50 +0300 |
| commit | 0711d857605ba598cd6d4254462d1419b233321b (patch) | |
| tree | cb8793180ab496b299eaab0c21fc29fb6f3e763b /drivers/serial | |
| parent | db288381e26e592b11572ce8199bedeadf0c0830 (diff) | |
| download | linux-0711d857605ba598cd6d4254462d1419b233321b.tar.xz | |
Blackfin Serial Driver: Fix bug - Increase buffer tail immediately before starting tx dma.
http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=2920
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Diffstat (limited to 'drivers/serial')
| -rw-r--r-- | drivers/serial/bfin_5xx.c | 32 |
1 files changed, 18 insertions, 14 deletions
diff --git a/drivers/serial/bfin_5xx.c b/drivers/serial/bfin_5xx.c index 69ac7007682e..2fb3081c5022 100644 --- a/drivers/serial/bfin_5xx.c +++ b/drivers/serial/bfin_5xx.c @@ -64,15 +64,20 @@ static void bfin_serial_mctrl_check(struct bfin_serial_port *uart); static void bfin_serial_stop_tx(struct uart_port *port) { struct bfin_serial_port *uart = (struct bfin_serial_port *)port; + struct circ_buf *xmit = &uart->port.info->xmit; #if !defined(CONFIG_BF54x) && !defined(CONFIG_SERIAL_BFIN_DMA) unsigned short ier; #endif while (!(UART_GET_LSR(uart) & TEMT)) - continue; + cpu_relax(); #ifdef CONFIG_SERIAL_BFIN_DMA disable_dma(uart->tx_dma_channel); + xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1); + uart->port.icount.tx += uart->tx_count; + uart->tx_count = 0; + uart->tx_done = 1; #else #ifdef CONFIG_BF54x /* Clear TFI bit */ @@ -94,7 +99,8 @@ static void bfin_serial_start_tx(struct uart_port *port) struct bfin_serial_port *uart = (struct bfin_serial_port *)port; #ifdef CONFIG_SERIAL_BFIN_DMA - bfin_serial_dma_tx_chars(uart); + if (uart->tx_done) + bfin_serial_dma_tx_chars(uart); #else #ifdef CONFIG_BF54x UART_SET_IER(uart, ETBEI); @@ -389,12 +395,10 @@ static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart) unsigned short ier; int flags = 0; - if (!uart->tx_done) - return; uart->tx_done = 0; if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) { - bfin_serial_stop_tx(&uart->port); + uart->tx_count = 0; uart->tx_done = 1; return; } @@ -428,9 +432,6 @@ static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart) set_dma_x_modify(uart->tx_dma_channel, 1); enable_dma(uart->tx_dma_channel); - xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1); - uart->port.icount.tx += uart->tx_count; - #ifdef CONFIG_BF54x UART_SET_IER(uart, ETBEI); #else @@ -515,8 +516,8 @@ static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id) spin_lock(&uart->port.lock); if (!(get_dma_curr_irqstat(uart->tx_dma_channel)&DMA_RUN)) { - clear_dma_irqstat(uart->tx_dma_channel); disable_dma(uart->tx_dma_channel); + clear_dma_irqstat(uart->tx_dma_channel); #ifdef CONFIG_BF54x UART_CLEAR_IER(uart, ETBEI); #else @@ -527,7 +528,8 @@ static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id) if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(&uart->port); - uart->tx_done = 1; + xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1); + uart->port.icount.tx += uart->tx_count; bfin_serial_dma_tx_chars(uart); } @@ -542,12 +544,14 @@ static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id) unsigned short irqstat; uart->rx_dma_nrows++; - if (uart->rx_dma_nrows == DMA_RX_YCOUNT) { + uart->rx_dma_buf.tail = DMA_RX_XCOUNT * uart->rx_dma_nrows; + bfin_serial_dma_rx_chars(uart); + if (uart->rx_dma_nrows >= DMA_RX_YCOUNT) { uart->rx_dma_nrows = 0; - uart->rx_dma_buf.tail = DMA_RX_XCOUNT*DMA_RX_YCOUNT; - bfin_serial_dma_rx_chars(uart); - uart->rx_dma_buf.head = uart->rx_dma_buf.tail = 0; + uart->rx_dma_buf.tail = 0; } + uart->rx_dma_buf.head = uart->rx_dma_buf.tail; + spin_lock(&uart->port.lock); irqstat = get_dma_curr_irqstat(uart->rx_dma_channel); clear_dma_irqstat(uart->rx_dma_channel); |