Re: [U-Boot] [PATCH 3/7] ti: wdt: omap: Disable watchdog timer before performing initialization

[Lukasz Majewski]

Hi Tom,

> On Sun, Feb 19, 2017 at 11:24:38PM +0100, Lukasz Majewski wrote:
> 
> > The OMAP WDT IP block requires to be stopped before any write to its
> > registers is performed.
> > 
> > This problem has been thoroughly described in Linux kernel:
> > 
> > "watchdog: omap: assert the counter being stopped before
> > reprogramming: SHA1: 530c11d432727c697629ad5f9d00ee8e2864d453
> > 
> > Signed-off-by: Lukasz Majewski 
> 
> Reviewed-by: Tom Rini 
> 

Could this patch be applied alone? Preparing reset of this patch set is
a bit more tricky (since includes verbose testing).


Best regards,

Lukasz Majewski

--

DENX Software Engineering GmbH,  Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: w...@denx.de


pgp9sRoNGr4_g.pgp
Description: OpenPGP digital signature
___
U-Boot mailing list
U-Boot@lists.denx.de
https://lists.denx.de/listinfo/u-boot

Re: [U-Boot] [PATCH 3/7] ti: wdt: omap: Disable watchdog timer before performing initialization

[Tom Rini]

On Sun, Feb 19, 2017 at 11:24:38PM +0100, Lukasz Majewski wrote:

> The OMAP WDT IP block requires to be stopped before any write to its
> registers is performed.
> 
> This problem has been thoroughly described in Linux kernel:
> 
> "watchdog: omap: assert the counter being stopped before reprogramming:
> SHA1: 530c11d432727c697629ad5f9d00ee8e2864d453
> 
> Signed-off-by: Lukasz Majewski 

Reviewed-by: Tom Rini 

-- 
Tom


signature.asc
Description: Digital signature
___
U-Boot mailing list
U-Boot@lists.denx.de
http://lists.denx.de/mailman/listinfo/u-boot

[U-Boot] [PATCH 3/7] ti: wdt: omap: Disable watchdog timer before performing initialization

[Lukasz Majewski]

The OMAP WDT IP block requires to be stopped before any write to its
registers is performed.

This problem has been thoroughly described in Linux kernel:

"watchdog: omap: assert the counter being stopped before reprogramming:
SHA1: 530c11d432727c697629ad5f9d00ee8e2864d453

Signed-off-by: Lukasz Majewski 
---
 drivers/watchdog/omap_wdt.c | 37 ++---
 1 file changed, 22 insertions(+), 15 deletions(-)

diff --git a/drivers/watchdog/omap_wdt.c b/drivers/watchdog/omap_wdt.c
index 7ea4b60..7b1f429 100644
--- a/drivers/watchdog/omap_wdt.c
+++ b/drivers/watchdog/omap_wdt.c
@@ -81,10 +81,32 @@ static int omap_wdt_set_timeout(unsigned int timeout)
return 0;
 }
 
+void hw_watchdog_disable(void)
+{
+   struct wd_timer *wdt = (struct wd_timer *)WDT_BASE;
+
+   /*
+* Disable watchdog
+*/
+   writel(0x, >wdtwspr);
+   while (readl(>wdtwwps) != 0x0)
+   ;
+   writel(0x, >wdtwspr);
+   while (readl(>wdtwwps) != 0x0)
+   ;
+}
+
 void hw_watchdog_init(void)
 {
struct wd_timer *wdt = (struct wd_timer *)WDT_BASE;
 
+   /*
+* Make sure the watchdog is disabled. This is unfortunately required
+* because writing to various registers with the watchdog running has no
+* effect.
+*/
+   hw_watchdog_disable();
+
/* initialize prescaler */
while (readl(>wdtwwps) & WDT_WWPS_PEND_WCLR)
;
@@ -104,18 +126,3 @@ void hw_watchdog_init(void)
while ((readl(>wdtwwps)) & WDT_WWPS_PEND_WSPR)
;
 }
-
-void hw_watchdog_disable(void)
-{
-   struct wd_timer *wdt = (struct wd_timer *)WDT_BASE;
-
-   /*
-* Disable watchdog
-*/
-   writel(0x, >wdtwspr);
-   while (readl(>wdtwwps) != 0x0)
-   ;
-   writel(0x, >wdtwspr);
-   while (readl(>wdtwwps) != 0x0)
-   ;
-}
-- 
2.1.4

___
U-Boot mailing list
U-Boot@lists.denx.de
http://lists.denx.de/mailman/listinfo/u-boot