pch_uart : Reduce memcpy
authorTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Wed, 23 Feb 2011 01:03:14 +0000 (10:03 +0900)
committerGreg Kroah-Hartman <gregkh@suse.de>
Wed, 23 Feb 2011 01:22:03 +0000 (17:22 -0800)
Reduce memcpy for performance improvement.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/tty/serial/pch_uart.c

index 9e1b865..0e171b8 100644 (file)
@@ -390,7 +390,7 @@ static u8 pch_uart_hal_get_modem(struct eg20t_port *priv)
        return get_msr(priv, priv->membase);
 }
 
-static int pch_uart_hal_write(struct eg20t_port *priv,
+static void pch_uart_hal_write(struct eg20t_port *priv,
                              const unsigned char *buf, int tx_size)
 {
        int i;
@@ -400,7 +400,6 @@ static int pch_uart_hal_write(struct eg20t_port *priv,
                thr = buf[i++];
                iowrite8(thr, priv->membase + PCH_UART_THR);
        }
-       return i;
 }
 
 static int pch_uart_hal_read(struct eg20t_port *priv, unsigned char *buf,
@@ -634,7 +633,7 @@ static void pch_dma_tx_complete(void *arg)
                pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_TX_INT);
 }
 
-static int pop_tx(struct eg20t_port *priv, unsigned char *buf, int size)
+static int pop_tx(struct eg20t_port *priv, int size)
 {
        int count = 0;
        struct uart_port *port = &priv->port;
@@ -647,7 +646,7 @@ static int pop_tx(struct eg20t_port *priv, unsigned char *buf, int size)
                int cnt_to_end =
                    CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
                int sz = min(size - count, cnt_to_end);
-               memcpy(&buf[count], &xmit->buf[xmit->tail], sz);
+               pch_uart_hal_write(priv, &xmit->buf[xmit->tail], sz);
                xmit->tail = (xmit->tail + sz) & (UART_XMIT_SIZE - 1);
                count += sz;
        } while (!uart_circ_empty(xmit) && count < size);
@@ -723,7 +722,6 @@ static unsigned int handle_tx(struct eg20t_port *priv)
 {
        struct uart_port *port = &priv->port;
        struct circ_buf *xmit = &port->state->xmit;
-       int ret;
        int fifo_size;
        int tx_size;
        int size;
@@ -748,10 +746,9 @@ static unsigned int handle_tx(struct eg20t_port *priv)
        if (size < 0)
                size = fifo_size;
 
-       tx_size = pop_tx(priv, xmit->buf, size);
+       tx_size = pop_tx(priv, size);
        if (tx_size > 0) {
-               ret = pch_uart_hal_write(priv, xmit->buf, tx_size);
-               port->icount.tx += ret;
+               port->icount.tx += tx_size;
                tx_empty = 0;
        }