The NPCM750 have the following nine resets:
- Power on reset.
- Core reset
- Watchdog0-2 resets.
- Software1-4 resets
During probe NPCM watchdog sets WDIOF_CARDRESET, WDIOF_EXTERN1 and
WDIOF_EXTERN2 bootstatus flags.
Each bootstatus flag can represent one of the NPCM750 resets.
Bootstatus flag configure by the DT properties.
Signed-off-by: Tomer Maimon <tmaimon77@xxxxxxxxx>
---
drivers/watchdog/npcm_wdt.c | 112 ++++++++++++++++++++++++++++++++++++
1 file changed, 112 insertions(+)
diff --git a/drivers/watchdog/npcm_wdt.c b/drivers/watchdog/npcm_wdt.c
index 9c773c3d6d5d..84a728af6664 100644
--- a/drivers/watchdog/npcm_wdt.c
+++ b/drivers/watchdog/npcm_wdt.c
@@ -6,12 +6,29 @@
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
+#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/watchdog.h>
+/* NPCM7xx GCR module */
+#define NPCM7XX_RESSR_OFFSET 0x6C
+#define NPCM7XX_INTCR2_OFFSET 0x60
+
+#define NPCM7XX_PORST BIT(31)
+#define NPCM7XX_CORST BIT(30)
+#define NPCM7XX_WD0RST BIT(29)
+#define NPCM7XX_WD1RST BIT(24)
+#define NPCM7XX_WD2RST BIT(23)
+#define NPCM7XX_SWR1RST BIT(28)
+#define NPCM7XX_SWR2RST BIT(27)
+#define NPCM7XX_SWR3RST BIT(26)
+#define NPCM7XX_SWR4RST BIT(25)
+
+ /* WD register */
#define NPCM_WTCR 0x1C
#define NPCM_WTCLK (BIT(10) | BIT(11)) /* Clock divider */
@@ -43,6 +60,9 @@
struct npcm_wdt {
struct watchdog_device wdd;
void __iomem *reg;
+ u32 card_reset;
+ u32 ext1_reset;
+ u32 ext2_reset;
};
static inline struct npcm_wdt *to_npcm_wdt(struct watchdog_device *wdd)
@@ -177,9 +197,66 @@ static const struct watchdog_ops npcm_wdt_ops = {
.restart = npcm_wdt_restart,
};
+static void npcm_get_reset_status(struct npcm_wdt *wdt, struct device *dev)
+{
+ struct regmap *gcr_regmap;
+ u32 rstval;
+
+ if (of_device_is_compatible(dev->of_node, "nuvoton,npcm750-wdt")) {
+ gcr_regmap = syscon_regmap_lookup_by_compatible("nuvoton,npcm750-gcr");
+ if (IS_ERR(gcr_regmap))
+ dev_warn(dev, "Failed to find nuvoton,npcm750-gcr WD reset status not supported\n");
+
+ /* Reading last reset status bit */
+ regmap_read(gcr_regmap, NPCM7XX_RESSR_OFFSET, &rstval);
+ /* In case of NPCM750 power on, the reset status copied to
+ * NPCM7XX_INTCR2_OFFSET register and then NPCM7XX_RESSR_OFFSET
+ * register is cleaned.
+ */
+ if (!rstval) {
+ regmap_read(gcr_regmap, NPCM7XX_INTCR2_OFFSET, &rstval);
+ rstval = ~rstval;
+ }
+
+ if (rstval & wdt->card_reset)
+ wdt->wdd.bootstatus |= WDIOF_CARDRESET;
+ if (rstval & wdt->ext1_reset)
+ wdt->wdd.bootstatus |= WDIOF_EXTERN1;
+ if (rstval & wdt->ext2_reset)
+ wdt->wdd.bootstatus |= WDIOF_EXTERN2;
+ }
+}
+
+static u32 npcm_wdt_reset_type(const char *reset_type)
+{
+ if (!strcmp(reset_type, "porst"))
+ return NPCM7XX_PORST;
+ else if (!strcmp(reset_type, "corst"))
+ return NPCM7XX_CORST;
+ else if (!strcmp(reset_type, "wd0"))
+ return NPCM7XX_WD0RST;
+ else if (!strcmp(reset_type, "wd1"))
+ return NPCM7XX_WD1RST;
+ else if (!strcmp(reset_type, "wd2"))
+ return NPCM7XX_WD2RST;
+ else if (!strcmp(reset_type, "sw1"))
+ return NPCM7XX_SWR1RST;
+ else if (!strcmp(reset_type, "sw2"))
+ return NPCM7XX_SWR2RST;
+ else if (!strcmp(reset_type, "sw3"))
+ return NPCM7XX_SWR3RST;
+ else if (!strcmp(reset_type, "sw4"))
+ return NPCM7XX_SWR4RST;
+
+ return 0;
+}
+
static int npcm_wdt_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
+ const char *card_reset_type;
+ const char *ext1_reset_type;
+ const char *ext2_reset_type;
struct npcm_wdt *wdt;
int irq;
int ret;
@@ -196,6 +273,39 @@ static int npcm_wdt_probe(struct platform_device *pdev)
if (irq < 0)
return irq;
+ ret = of_property_read_string(pdev->dev.of_node,
+ "nuvoton,card-reset-type",
+ &card_reset_type);
+ if (ret) {
+ wdt->card_reset = NPCM7XX_PORST;
+ } else {
+ wdt->card_reset = npcm_wdt_reset_type(card_reset_type);
+ if (!wdt->card_reset)
+ wdt->card_reset = NPCM7XX_PORST;
+ }
+
+ ret = of_property_read_string(pdev->dev.of_node,
+ "nuvoton,ext1-reset-type",
+ &ext1_reset_type);
+ if (ret) {
+ wdt->ext1_reset = NPCM7XX_WD0RST;
+ } else {
+ wdt->ext1_reset = npcm_wdt_reset_type(ext1_reset_type);
+ if (!wdt->ext1_reset)
+ wdt->ext1_reset = NPCM7XX_WD0RST;
+ }
+
+ ret = of_property_read_string(pdev->dev.of_node,
+ "nuvoton,ext2-reset-type",
+ &ext2_reset_type);
+ if (ret) {
+ wdt->ext2_reset = NPCM7XX_SWR1RST;
+ } else {
+ wdt->ext2_reset = npcm_wdt_reset_type(ext2_reset_type);
+ if (!wdt->ext2_reset)
+ wdt->ext2_reset = NPCM7XX_SWR1RST;
+ }
+
wdt->wdd.info = &npcm_wdt_info;
wdt->wdd.ops = &npcm_wdt_ops;
wdt->wdd.min_timeout = 1;
@@ -214,6 +324,8 @@ static int npcm_wdt_probe(struct platform_device *pdev)
set_bit(WDOG_HW_RUNNING, &wdt->wdd.status);
}
+ npcm_get_reset_status(wdt, dev);
+
ret = devm_request_irq(dev, irq, npcm_wdt_interrupt, 0, "watchdog",
wdt);
if (ret)
--
2.22.0
