[PATCH v3 3/3] watchdog: sunxi_wdt: Add support for D1

Samuel Holland
2021-09-02T22:58:15Z

D1 adds a key field to the "CFG" and "MODE" registers, that must be set
to change the other bits. Add logic to set the key when updating those
registers.

Acked-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Samuel Holland <samuel@sholland.org>
---
Changes v2 to v3:
- None
Changes v1 to v2:
- None

drivers/watchdog/sunxi_wdt.c | 20 +++++++++++++++++++-
1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/drivers/watchdog/sunxi_wdt.c b/drivers/watchdog/sunxi_wdt.c
index b50757882a98..6cf82922d3fb 100644
--- a/drivers/watchdog/sunxi_wdt.c
+++ b/drivers/watchdog/sunxi_wdt.c
@@ -48,6 +48,7 @@ struct sunxi_wdt_reg {
u8 wdt_timeout_shift;
u8 wdt_reset_mask;
u8 wdt_reset_val;
+ u32 wdt_key_val;
};

struct sunxi_wdt_dev {
@@ -91,12 +92,14 @@ static int sunxi_wdt_restart(struct watchdog_device *wdt_dev,
val = readl(wdt_base + regs->wdt_cfg);
val &= ~(regs->wdt_reset_mask);
val |= regs->wdt_reset_val;
+ val |= regs->wdt_key_val;
writel(val, wdt_base + regs->wdt_cfg);

/* Set lowest timeout and enable watchdog */
val = readl(wdt_base + regs->wdt_mode);
val &= ~(WDT_TIMEOUT_MASK << regs->wdt_timeout_shift);
val |= WDT_MODE_EN;
+ val |= regs->wdt_key_val;
writel(val, wdt_base + regs->wdt_mode);

/*
@@ -109,6 +112,7 @@ static int sunxi_wdt_restart(struct watchdog_device *wdt_dev,
mdelay(5);
val = readl(wdt_base + regs->wdt_mode);
val |= WDT_MODE_EN;
+ val |= regs->wdt_key_val;
writel(val, wdt_base + regs->wdt_mode);
}
return 0;
@@ -141,6 +145,7 @@ static int sunxi_wdt_set_timeout(struct watchdog_device *wdt_dev,
reg = readl(wdt_base + regs->wdt_mode);
reg &= ~(WDT_TIMEOUT_MASK << regs->wdt_timeout_shift);
reg |= wdt_timeout_map[timeout] << regs->wdt_timeout_shift;
+ reg |= regs->wdt_key_val;
writel(reg, wdt_base + regs->wdt_mode);

sunxi_wdt_ping(wdt_dev);
@@ -154,7 +159,7 @@ static int sunxi_wdt_stop(struct watchdog_device *wdt_dev)
void __iomem *wdt_base = sunxi_wdt->wdt_base;
const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs;

- writel(0, wdt_base + regs->wdt_mode);
+ writel(regs->wdt_key_val, wdt_base + regs->wdt_mode);

return 0;
}
@@ -176,11 +181,13 @@ static int sunxi_wdt_start(struct watchdog_device *wdt_dev)
reg = readl(wdt_base + regs->wdt_cfg);
reg &= ~(regs->wdt_reset_mask);
reg |= regs->wdt_reset_val;
+ reg |= regs->wdt_key_val;
writel(reg, wdt_base + regs->wdt_cfg);

/* Enable watchdog */
reg = readl(wdt_base + regs->wdt_mode);
reg |= WDT_MODE_EN;
+ reg |= regs->wdt_key_val;
writel(reg, wdt_base + regs->wdt_mode);

return 0;
@@ -220,9 +227,20 @@ static const struct sunxi_wdt_reg sun6i_wdt_reg = {
.wdt_reset_val = 0x01,
};

+static const struct sunxi_wdt_reg sun20i_wdt_reg = {
+ .wdt_ctrl = 0x10,
+ .wdt_cfg = 0x14,
+ .wdt_mode = 0x18,
+ .wdt_timeout_shift = 4,
+ .wdt_reset_mask = 0x03,
+ .wdt_reset_val = 0x01,
+ .wdt_key_val = 0x16aa0000,
+};
+
static const struct of_device_id sunxi_wdt_dt_ids[] = {
{ .compatible = "allwinner,sun4i-a10-wdt", .data = &sun4i_wdt_reg },
{ .compatible = "allwinner,sun6i-a31-wdt", .data = &sun6i_wdt_reg },
+ { .compatible = "allwinner,sun20i-d1-wdt", .data = &sun20i_wdt_reg },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, sunxi_wdt_dt_ids);
--
2.31.1