From: Qipan Li <Qipan.Li@xxxxxxx>
the current codes send 1 bytes, then after getting TX done interrupt,
send subsequent bytes. it causes redundant interrupts.
for example, if we have 3 bytes in TX buffer, the TX flow is:
1. send 1 byte
2. get TX down interrupt
3. send the left 2 bytes
4. get TX down interrupt
this patch moves to send more bytes and decrease interrupts, the new
flow is:
1. send 3 bytes
2. get TX down interrupt
Signed-off-by: Qipan Li <Qipan.Li@xxxxxxx>
Signed-off-by: Barry Song <Baohua.Song@xxxxxxx>
---
drivers/tty/serial/sirfsoc_uart.c | 3 ++-
drivers/tty/serial/sirfsoc_uart.h | 2 +-
2 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/sirfsoc_uart.c b/drivers/tty/serial/sirfsoc_uart.c
index 9b4d71c..4102192 100644
--- a/drivers/tty/serial/sirfsoc_uart.c
+++ b/drivers/tty/serial/sirfsoc_uart.c
@@ -290,7 +290,8 @@ static void sirfsoc_uart_start_tx(struct uart_port *port)
if (sirfport->tx_dma_chan)
sirfsoc_uart_tx_with_dma(sirfport);
else {
- sirfsoc_uart_pio_tx_chars(sirfport, 1);
+ sirfsoc_uart_pio_tx_chars(sirfport,
+ SIRFSOC_UART_IO_TX_REASONABLE_CNT);
wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
if (!sirfport->is_marco)
wr_regl(port, ureg->sirfsoc_int_en_reg,
diff --git a/drivers/tty/serial/sirfsoc_uart.h b/drivers/tty/serial/sirfsoc_uart.h
index 69a62eb..6a7ebf7 100644
--- a/drivers/tty/serial/sirfsoc_uart.h
+++ b/drivers/tty/serial/sirfsoc_uart.h
@@ -449,4 +449,4 @@ struct sirfsoc_uart_port {
/* I/O Mode */
#define SIRFSOC_UART_IO_RX_MAX_CNT 256
-#define SIRFSOC_UART_IO_TX_REASONABLE_CNT 6
+#define SIRFSOC_UART_IO_TX_REASONABLE_CNT 256
--
1.9.3
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