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* [PATCH] tty: amba-pl011: uart_amba_port is not available with earlycon function
@ 2016-09-17  6:14 Shawn Guo
  2016-09-20 13:05 ` Shawn Guo
  0 siblings, 1 reply; 4+ messages in thread
From: Shawn Guo @ 2016-09-17  6:14 UTC (permalink / raw)
  To: linux-arm-kernel

Commit 0e125a5facf8 ("tty: amba-pl011: define flag register bits for ZTE
device") changes earlycon function pl011_putc() to use a pointer to
uart_amba_port.  This causes a regression when earlycon is enabled,
because uart_amba_port is not available yet at earlycon time.  Let's
revert the change on pl011_putc() to fix the regression.

The earlycon support for ZTE device can probably be added later by
declaring a new earlycon setup function with a vendor specific
compatible.

Reported-by: Sudeep Holla <sudeep.holla@arm.com>
Fixes: 0e125a5facf8 ("tty: amba-pl011: define flag register bits for ZTE device")
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
---
 drivers/tty/serial/amba-pl011.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 0b78b04e895e..2d9ffab16ffe 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2330,16 +2330,13 @@ static struct console amba_console = {
 
 static void pl011_putc(struct uart_port *port, int c)
 {
-	struct uart_amba_port *uap =
-		container_of(port, struct uart_amba_port, port);
-
 	while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF)
 		cpu_relax();
 	if (port->iotype == UPIO_MEM32)
 		writel(c, port->membase + UART01x_DR);
 	else
 		writeb(c, port->membase + UART01x_DR);
-	while (readl(port->membase + UART01x_FR) & uap->vendor->fr_busy)
+	while (readl(port->membase + UART01x_FR) & UART01x_FR_BUSY)
 		cpu_relax();
 }
 
-- 
1.9.1

^ permalink raw reply related	[flat|nested] 4+ messages in thread

* [PATCH] tty: amba-pl011: uart_amba_port is not available with earlycon function
  2016-09-17  6:14 [PATCH] tty: amba-pl011: uart_amba_port is not available with earlycon function Shawn Guo
@ 2016-09-20 13:05 ` Shawn Guo
  2016-09-20 13:15   ` Sudeep Holla
  0 siblings, 1 reply; 4+ messages in thread
From: Shawn Guo @ 2016-09-20 13:05 UTC (permalink / raw)
  To: linux-arm-kernel

On Sat, Sep 17, 2016 at 02:14:38PM +0800, Shawn Guo wrote:
> Commit 0e125a5facf8 ("tty: amba-pl011: define flag register bits for ZTE
> device") changes earlycon function pl011_putc() to use a pointer to
> uart_amba_port.  This causes a regression when earlycon is enabled,
> because uart_amba_port is not available yet at earlycon time.  Let's
> revert the change on pl011_putc() to fix the regression.
> 
> The earlycon support for ZTE device can probably be added later by
> declaring a new earlycon setup function with a vendor specific
> compatible.
> 
> Reported-by: Sudeep Holla <sudeep.holla@arm.com>
> Fixes: 0e125a5facf8 ("tty: amba-pl011: define flag register bits for ZTE device")
> Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

Hi Sudeep,

Can you please confirm if the patch fixes your problem, so that Greg
knows whether it should be applied?  Thanks.

Shawn

^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH] tty: amba-pl011: uart_amba_port is not available with earlycon function
  2016-09-20 13:05 ` Shawn Guo
@ 2016-09-20 13:15   ` Sudeep Holla
  2016-09-20 13:23     ` Shawn Guo
  0 siblings, 1 reply; 4+ messages in thread
From: Sudeep Holla @ 2016-09-20 13:15 UTC (permalink / raw)
  To: linux-arm-kernel



On 20/09/16 14:05, Shawn Guo wrote:
> On Sat, Sep 17, 2016 at 02:14:38PM +0800, Shawn Guo wrote:
>> Commit 0e125a5facf8 ("tty: amba-pl011: define flag register bits for ZTE
>> device") changes earlycon function pl011_putc() to use a pointer to
>> uart_amba_port.  This causes a regression when earlycon is enabled,
>> because uart_amba_port is not available yet at earlycon time.  Let's
>> revert the change on pl011_putc() to fix the regression.
>>
>> The earlycon support for ZTE device can probably be added later by
>> declaring a new earlycon setup function with a vendor specific
>> compatible.
>>
>> Reported-by: Sudeep Holla <sudeep.holla@arm.com>
>> Fixes: 0e125a5facf8 ("tty: amba-pl011: define flag register bits for ZTE device")
>> Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
>
> Hi Sudeep,
>
> Can you please confirm if the patch fixes your problem, so that Greg
> knows whether it should be applied?  Thanks.
>

Sorry, since it's basically what I tried first before posting some patch
using private_data, I assumed it will work.

Anyways I have now tested it, so you can add:
Tested-by: Sudeep Holla <sudeep.holla@arm.com>

-- 
Regards,
Sudeep

^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH] tty: amba-pl011: uart_amba_port is not available with earlycon function
  2016-09-20 13:15   ` Sudeep Holla
@ 2016-09-20 13:23     ` Shawn Guo
  0 siblings, 0 replies; 4+ messages in thread
From: Shawn Guo @ 2016-09-20 13:23 UTC (permalink / raw)
  To: linux-arm-kernel

On Tue, Sep 20, 2016 at 9:15 PM, Sudeep Holla <sudeep.holla@arm.com> wrote:
> Anyways I have now tested it, so you can add:
> Tested-by: Sudeep Holla <sudeep.holla@arm.com>

Sorry for the regression, and thanks much for the effort of issue
reporting and testing.

Shawn

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2016-09-20 13:23 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2016-09-17  6:14 [PATCH] tty: amba-pl011: uart_amba_port is not available with earlycon function Shawn Guo
2016-09-20 13:05 ` Shawn Guo
2016-09-20 13:15   ` Sudeep Holla
2016-09-20 13:23     ` Shawn Guo

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