Commit Graph

4 Commits

Author SHA1 Message Date
Alexandre Belloni
f201353273 watchdog: sama5d4: Implement resume hook
When resuming for the deepest state on sama5d2, it is necessary to restore
MR as the registers are lost.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-02-24 14:00:23 -08:00
Alexandre Belloni
722ce6356d watchdog: sama5d4: Cache MR instead of a partial config
.config is used to cache a part of WDT_MR at probe time and is not used
afterwards. Instead of doing that, actually cache MR and avoid reading it
every time it is modified.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-02-24 14:00:23 -08:00
Bhumika Goyal
b893e344bf watchdog: constify watchdog_ops structures
Declare watchdog_ops structures as const as they are only stored in the
ops field of a watchdog_device structure. This field is of type const, so
watchdog_ops structures having this property can be made const too.
Done using Coccinelle:

@r disable optional_qualifier@
identifier x;
position p;
@@
static struct watchdog_ops x@p={...};

@ok@
struct watchdog_device w;
identifier r.x;
position p;
@@
w.ops=&x@p;

@bad@
position p != {r.p,ok.p};
identifier r.x;
@@
x@p

@depends on !bad disable optional_qualifier@
identifier r.x;
@@
+const
struct watchdog_ops x;

File size details before and after patching.
First line of every .o file shows the file size before patching
and second line shows the size after patching.

   text    data     bss     dec     hex filename

   1340	    544	      0	   1884	    75c	drivers/watchdog/bcm_kona_wdt.o
   1436	    440	      0	   1876	    754	drivers/watchdog/bcm_kona_wdt.o

   1176	    544	      4	   1724	    6bc	drivers/watchdog/digicolor_wdt.o
   1272	    440	      4	   1716	    6b4	drivers/watchdog/digicolor_wdt.o

    925	    580	     89	   1594	    63a	drivers/watchdog/ep93xx_wdt.o
   1021	    476	     89	   1586	    632	drivers/watchdog/ep93xx_wdt.o

   4932	    288	     17	   5237	   1475	drivers/watchdog/s3c2410_wdt.o
   5028	    192	     17	   5237	   1475	drivers/watchdog/s3c2410_wdt.o

   1977	    292	      1	   2270	    8de	drivers/watchdog/sama5d4_wdt.o
   2073	    196	      1	   2270	    8de	drivers/watchdog/sama5d4_wdt.o

   1375	    484	      1	   1860	    744	drivers/watchdog/sirfsoc_wdt.o
   1471	    380	      1	   1852	    73c	drivers/watchdog/sirfsoc_wdt.o

Size remains the same for the files drivers/watchdog/diag288_wdt.o
drivers/watchdog/asm9260_wdt.o and drivers/watchdog/atlas7_wdt.o

The following .o files did not compile:
drivers/watchdog/sun4v_wdt.o, drivers/watchdog/sbsa_gwdt.o,
drivers/watchdog/rt2880_wdt.o, drivers/watchdog/booke_wdt.o
drivers/watchdog/mt7621_wdt.o

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2017-02-24 14:00:23 -08:00
Wenyou Yang
76534860f1 watchdog: add a driver to support SAMA5D4 watchdog timer
From SAMA5D4, the watchdog timer is upgrated with a new feature,
which is describled as in the datasheet, "WDT_MR can be written
until a LOCKMR command is issued in WDT_CR".
That is to say, as long as the bootstrap and u-boot don't issue
a LOCKMR command, WDT_MR can be written more than once in the driver.

So the SAMA5D4 watchdog driver's implementation is different from
the at91sam9260 watchdog driver implemented in file at91sam9_wdt.c.
The user application open the device file to enable the watchdog timer
hardware, and close to disable it, and set the watchdog timer timeout
by seting WDV and WDD fields of WDT_MR register, and ping the watchdog
by issuing WDRSTT command to WDT_CR register with hard-coded key.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-09-09 21:38:29 +02:00