[PATCH 15/19] serial: bfin_5xx: remove redundant SSYNC to improve TX speed

From: Greg Kroah-Hartman
Date: Fri Nov 12 2010 - 16:41:51 EST


From: Sonic Zhang <sonic.zhang@xxxxxxxxxx>

We don't need to force a SSYNC here as the LSR register will already
be updated by the time we get back to reading it. This speeds up TX
throughput and lowers general system overhead (since SSYNC is system
wide, not peripheral-specific).

Signed-off-by: Sonic Zhang <sonic.zhang@xxxxxxxxxx>
Signed-off-by: Mike Frysinger <vapier@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
drivers/serial/bfin_5xx.c | 1 -
1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/drivers/serial/bfin_5xx.c b/drivers/serial/bfin_5xx.c
index c8ca3b4..a454e42 100644
--- a/drivers/serial/bfin_5xx.c
+++ b/drivers/serial/bfin_5xx.c
@@ -359,7 +359,6 @@ static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
UART_PUT_CHAR(uart, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
uart->port.icount.tx++;
- SSYNC();
}

if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
--
1.7.1

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