From 56f5de8fe7c127f6fb94b7a061d53090fd4a1c49 Mon Sep 17 00:00:00 2001 From: Sonic Zhang Date: Mon, 25 Feb 2008 15:19:09 +0800 Subject: [PATCH] Blackfin Serial Driver: Fix bug - update tx dma buffer tail before wake up processes. Also make rx dma buffer work as a loop. Signed-off-by: Sonic Zhang Signed-off-by: Bryan Wu --- drivers/serial/bfin_5xx.c | 51 ++++++++++++++++++++++----------------- 1 file changed, 29 insertions(+), 22 deletions(-) diff --git a/drivers/serial/bfin_5xx.c b/drivers/serial/bfin_5xx.c index 2fb3081c50..2a41174857 100644 --- a/drivers/serial/bfin_5xx.c +++ b/drivers/serial/bfin_5xx.c @@ -415,7 +415,6 @@ static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart) */ bfin_serial_mctrl_check(uart); - spin_lock_irqsave(&uart->port.lock, flags); uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE); if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail)) uart->tx_count = UART_XMIT_SIZE - xmit->tail; @@ -439,7 +438,6 @@ static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart) ier |= ETBEI; UART_PUT_IER(uart, ier); #endif - spin_unlock_irqrestore(&uart->port.lock, flags); } static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart) @@ -450,7 +448,9 @@ static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart) status = UART_GET_LSR(uart); UART_CLEAR_LSR(uart); - uart->port.icount.rx += CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail, UART_XMIT_SIZE);; + uart->port.icount.rx += + CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail, + UART_XMIT_SIZE); if (status & BI) { uart->port.icount.brk++; @@ -476,10 +476,12 @@ static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart) else flg = TTY_NORMAL; - for (i = uart->rx_dma_buf.head; i < uart->rx_dma_buf.tail; i++) { - if (uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i])) - goto dma_ignore_char; - uart_insert_char(&uart->port, status, OE, uart->rx_dma_buf.buf[i], flg); + for (i = uart->rx_dma_buf.tail; i != uart->rx_dma_buf.head; i++) { + if (i >= UART_XMIT_SIZE) + i = 0; + if (!uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i])) + uart_insert_char(&uart->port, status, OE, + uart->rx_dma_buf.buf[i], flg); } dma_ignore_char: @@ -492,16 +494,20 @@ void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart) int flags = 0; spin_lock_irqsave(&uart->port.lock, flags); - x_pos = DMA_RX_XCOUNT - get_dma_curr_xcount(uart->rx_dma_channel); + uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel); + x_pos = get_dma_curr_xcount(uart->rx_dma_channel); + uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows; + if (uart->rx_dma_nrows == DMA_RX_YCOUNT) + uart->rx_dma_nrows = 0; + x_pos = DMA_RX_XCOUNT - x_pos; if (x_pos == DMA_RX_XCOUNT) x_pos = 0; pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos; - - if (pos>uart->rx_dma_buf.tail) { - uart->rx_dma_buf.tail = pos; + if (pos != uart->rx_dma_buf.tail) { + uart->rx_dma_buf.head = pos; bfin_serial_dma_rx_chars(uart); - uart->rx_dma_buf.head = uart->rx_dma_buf.tail; + uart->rx_dma_buf.tail = uart->rx_dma_buf.head; } spin_unlock_irqrestore(&uart->port.lock, flags); uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES; @@ -525,12 +531,12 @@ static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id) ier &= ~ETBEI; UART_PUT_IER(uart, ier); #endif - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(&uart->port); - xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1); uart->port.icount.tx += uart->tx_count; + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(&uart->port); + bfin_serial_dma_tx_chars(uart); } @@ -542,15 +548,16 @@ static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id) { struct bfin_serial_port *uart = dev_id; unsigned short irqstat; + int pos; - uart->rx_dma_nrows++; - 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 = 0; + uart->rx_dma_nrows = DMA_RX_YCOUNT - + get_dma_curr_ycount(uart->rx_dma_channel); + pos = DMA_RX_XCOUNT * uart->rx_dma_nrows; + if (pos != uart->rx_dma_buf.tail) { + uart->rx_dma_buf.head = pos; + bfin_serial_dma_rx_chars(uart); + uart->rx_dma_buf.tail = uart->rx_dma_buf.head; } - uart->rx_dma_buf.head = uart->rx_dma_buf.tail; spin_lock(&uart->port.lock); irqstat = get_dma_curr_irqstat(uart->rx_dma_channel); -- 2.39.5