msm_serial: Send more than 1 character on the console w/ UARTDM
authorStephen Boyd <sboyd@codeaurora.org>
Wed, 21 Aug 2013 06:48:06 +0000 (23:48 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 27 Aug 2013 23:22:59 +0000 (16:22 -0700)
We recently added support to send more than one character at a
time for UARTDM hardware but we didn't add the same support in
the console code path. Add support here to speed up console
messages on UARTDM hardware.

Cc: David Brown <davidb@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/serial/msm_serial.c

index 5a7503986d7dba61708a79dabe5bd594589b5037..b5d779cd3c2b182743c728e71198ce75a60a9692 100644 (file)
@@ -769,32 +769,63 @@ static inline struct uart_port *get_port_from_line(unsigned int line)
 }
 
 #ifdef CONFIG_SERIAL_MSM_CONSOLE
-
-static void msm_console_putchar(struct uart_port *port, int c)
-{
-       struct msm_port *msm_port = UART_TO_MSM(port);
-
-       if (msm_port->is_uartdm)
-               reset_dm_count(port, 1);
-
-       while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
-               ;
-       msm_write(port, c, msm_port->is_uartdm ? UARTDM_TF : UART_TF);
-}
-
 static void msm_console_write(struct console *co, const char *s,
                              unsigned int count)
 {
+       int i;
        struct uart_port *port;
        struct msm_port *msm_port;
+       int num_newlines = 0;
+       bool replaced = false;
 
        BUG_ON(co->index < 0 || co->index >= UART_NR);
 
        port = get_port_from_line(co->index);
        msm_port = UART_TO_MSM(port);
 
+       /* Account for newlines that will get a carriage return added */
+       for (i = 0; i < count; i++)
+               if (s[i] == '\n')
+                       num_newlines++;
+       count += num_newlines;
+
        spin_lock(&port->lock);
-       uart_console_write(port, s, count, msm_console_putchar);
+       if (msm_port->is_uartdm)
+               reset_dm_count(port, count);
+
+       i = 0;
+       while (i < count) {
+               int j;
+               unsigned int num_chars;
+               char buf[4] = { 0 };
+               unsigned int *bf = (unsigned int *)&buf;
+
+               if (msm_port->is_uartdm)
+                       num_chars = min(count - i, (unsigned int)sizeof(buf));
+               else
+                       num_chars = 1;
+
+               for (j = 0; j < num_chars; j++) {
+                       char c = *s;
+
+                       if (c == '\n' && !replaced) {
+                               buf[j] = '\r';
+                               j++;
+                               replaced = true;
+                       }
+                       if (j < num_chars) {
+                               buf[j] = c;
+                               s++;
+                               replaced = false;
+                       }
+               }
+
+               while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
+                       cpu_relax();
+
+               msm_write(port, *bf, msm_port->is_uartdm ? UARTDM_TF : UART_TF);
+               i += num_chars;
+       }
        spin_unlock(&port->lock);
 }