watchdog: Implement generic watchdog_reset() version

This patch tries to implement a generic watchdog_reset() function that
can be used by all boards that want to service the watchdog device in
U-Boot. This watchdog servicing is enabled via CONFIG_WATCHDOG.

Without this approach, new boards or platforms needed to implement a
board specific version of this functionality, mostly copy'ing the same
code over and over again into their board or platforms code base.

With this new generic function, the scattered other functions are now
removed to be replaced by the generic one. The new version also enables
the configuration of the watchdog timeout via the DT "timeout-sec"
property (if enabled via CONFIG_OF_CONTROL).

This patch also adds a new flag to the GD flags, to flag that the
watchdog is ready to use and adds the pointer to the watchdog device
to the GD. This enables us to remove the global "watchdog_dev"
variable, which was prone to cause problems because of its potentially
very early use in watchdog_reset(), even before the BSS is cleared.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Cc: Tom Rini <trini@konsulko.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: "Marek Behún" <marek.behun@nic.cz>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Maxim Sloyko <maxims@google.com>
Cc: Erik van Luijk <evanluijk@interact.nl>
Cc: Ryder Lee <ryder.lee@mediatek.com>
Cc: Weijie Gao <weijie.gao@mediatek.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: "Álvaro Fernández Rojas" <noltari@gmail.com>
Cc: Philippe Reynes <philippe.reynes@softathome.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Michal Simek <michal.simek@xilinx.com> (on zcu100)

1 files changed, 1 insertions, 35 deletions

diff --git a/board/alliedtelesis/x530/x530.c b/board/alliedtelesis/x530/x530.c
index 6934fd8017..97dbed79dd 100644
--- a/board/alliedtelesis/x530/x530.c
+++ b/board/alliedtelesis/x530/x530.c
@@ -25,10 +25,6 @@ DECLARE_GLOBAL_DATA_PTR;
 #define CONFIG_NVS_LOCATION		0xf4800000
 #define CONFIG_NVS_SIZE			(512 << 10)
 
-#ifdef CONFIG_WATCHDOG
-static struct udevice *watchdog_dev;
-#endif
-
 static struct serdes_map board_serdes_map[] = {
 	{PEX0, SERDES_SPEED_5_GBPS, PEX_ROOT_COMPLEX_X1, 0, 0},
 	{DEFAULT_SERDES, SERDES_SPEED_5_GBPS, SERDES_DEFAULT_MODE, 0, 0},
@@ -80,10 +76,6 @@ struct mv_ddr_topology_map *mv_ddr_topology_map_get(void)
 
 int board_early_init_f(void)
 {
-#ifdef CONFIG_WATCHDOG
-	watchdog_dev = NULL;
-#endif
-
 	/* Configure MPP */
 	writel(0x00001111, MVEBU_MPP_BASE + 0x00);
 	writel(0x00000000, MVEBU_MPP_BASE + 0x04);
@@ -99,13 +91,6 @@ int board_early_init_f(void)
 
 void spl_board_init(void)
 {
-#ifdef CONFIG_WATCHDOG
-	int ret;
-
-	ret = uclass_get_device(UCLASS_WDT, 0, &watchdog_dev);
-	if (!ret)
-		wdt_start(watchdog_dev, 120000, 0);
-#endif
 }
 
 int board_init(void)
@@ -128,29 +113,10 @@ int board_init(void)
 void arch_preboot_os(void)
 {
 #ifdef CONFIG_WATCHDOG
-	wdt_stop(watchdog_dev);
+	wdt_stop(gd->watchdog_dev);
 #endif
 }
 
-#ifdef CONFIG_WATCHDOG
-void watchdog_reset(void)
-{
-	static ulong next_reset = 0;
-	ulong now;
-
-	if (!watchdog_dev)
-		return;
-
-	now = timer_get_us();
-
-	/* Do not reset the watchdog too often */
-	if (now > next_reset) {
-		wdt_reset(watchdog_dev);
-		next_reset = now + 1000;
-	}
-}
-#endif
-
 static int led_7seg_init(unsigned int segments)
 {
 	int node;