Commit 1d6b6987 authored by Grant Likely's avatar Grant Likely Committed by Josh Boyer

[POWERPC] Uartlite: speed up console output

Change the wait_tx routine to call cpu_relax() instead of udelay() to
reduce console output latency and test for the TXFULL bit instead of
TXEMPTY.  That way the FIFO doesn't need to by 100% flushed before
writing the next character.
Signed-off-by: default avatarGrant Likely <grant.likely@secretlab.ca>
Acked-by: default avatarPeter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: default avatarJosh Boyer <jwboyer@linux.vnet.ibm.com>
parent 7ae0fa49
......@@ -329,12 +329,14 @@ static struct uart_ops ulite_ops = {
static void ulite_console_wait_tx(struct uart_port *port)
{
int i;
u8 val;
/* wait up to 10ms for the character(s) to be sent */
for (i = 0; i < 10000; i++) {
if (readb(port->membase + ULITE_STATUS) & ULITE_STATUS_TXEMPTY)
/* Spin waiting for TX fifo to have space available */
for (i = 0; i < 100000; i++) {
val = readb(port->membase + ULITE_STATUS);
if ((val & ULITE_STATUS_TXFULL) == 0)
break;
udelay(1);
cpu_relax();
}
}
......
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