On 1/25/23 10:57, ETIENNE DUBLE wrote:
This driver supports the bcm2835 watchdog found on Raspberry Pi boards. It is derived from the Linux driver and was tested on two Raspberry Pi board versions (B+ and 3B+).
Signed-off-by: Etienne Dublé etienne.duble@imag.fr
Reviewed-by: Stefan Roese sr@denx.de
Thanks, Stefan
Changes for v2:
- fixed whitespaces in email
- moved a static variable to the priv struct
Changes for v3:
used the max timeout value the hardware supports
turned the warning to a one-line message
drivers/watchdog/Kconfig | 9 +++ drivers/watchdog/Makefile | 1 + drivers/watchdog/bcm2835_wdt.c | 132 +++++++++++++++++++++++++++++++++ 3 files changed, 142 insertions(+) create mode 100644 drivers/watchdog/bcm2835_wdt.c
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index f1b1cf63ca..06c0d630c8 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -30,6 +30,7 @@ config WATCHDOG_TIMEOUT_MSECS default 128000 if ARCH_MX7 || ARCH_VF610 default 30000 if ARCH_SOCFPGA default 16000 if ARCH_SUNXI
- default 15000 if ARCH_BCM283X default 60000 help Watchdog timeout in msec
@@ -326,6 +327,14 @@ config WDT_SUNXI help Enable support for the watchdog timer in Allwinner sunxi SoCs.
+config WDT_BCM2835
- bool "Broadcom 2835 watchdog timer support"
- depends on WDT && ARCH_BCM283X
- default y
- help
Enable support for the watchdog timer in Broadcom 283X SoCs suchas Raspberry Pi boards.- config XILINX_TB_WATCHDOG bool "Xilinx Axi watchdog timer support" depends on WDT
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 446d961d7d..f99915960c 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -21,6 +21,7 @@ obj-$(CONFIG_WDT_APPLE) += apple_wdt.o obj-$(CONFIG_WDT_ARMADA_37XX) += armada-37xx-wdt.o obj-$(CONFIG_WDT_ASPEED) += ast_wdt.o obj-$(CONFIG_WDT_AST2600) += ast2600_wdt.o +obj-$(CONFIG_WDT_BCM2835) += bcm2835_wdt.o obj-$(CONFIG_WDT_BCM6345) += bcm6345_wdt.o obj-$(CONFIG_WDT_BOOKE) += booke_wdt.o obj-$(CONFIG_WDT_CORTINA) += cortina_wdt.o diff --git a/drivers/watchdog/bcm2835_wdt.c b/drivers/watchdog/bcm2835_wdt.c new file mode 100644 index 0000000000..3c1ead3dda --- /dev/null +++ b/drivers/watchdog/bcm2835_wdt.c @@ -0,0 +1,132 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright (C) 2013 Lubomir Rintel lkundrak@v3.sk
- Copyright (C) 2023 Etienne Dublé (CNRS) etienne.duble@imag.fr
- This code is mostly derived from the linux driver.
- */
+#include <dm.h> +#include <wdt.h> +#include <asm/io.h> +#include <linux/delay.h>
+#define PM_RSTC 0x1c +#define PM_WDOG 0x24
+#define PM_PASSWORD 0x5a000000
+/* The hardware supports a maximum timeout value of 0xfffff ticks
- (just below 16 seconds).
- */
+#define PM_WDOG_MAX_TICKS 0x000fffff +#define PM_RSTC_WRCFG_CLR 0xffffffcf +#define PM_RSTC_WRCFG_FULL_RESET 0x00000020 +#define PM_RSTC_RESET 0x00000102
+#define MS_TO_WDOG_TICKS(x) (((x) << 16) / 1000)
+struct bcm2835_wdt_priv {
- void __iomem *base;
- u64 timeout_ticks;
+};
+static int bcm2835_wdt_start_ticks(struct udevice *dev,
u64 timeout_ticks, ulong flags)+{
- struct bcm2835_wdt_priv *priv = dev_get_priv(dev);
- void __iomem *base = priv->base;
- u32 cur;
- writel(PM_PASSWORD | timeout_ticks, base + PM_WDOG);
- cur = readl(base + PM_RSTC);
- writel(PM_PASSWORD | (cur & PM_RSTC_WRCFG_CLR) | PM_RSTC_WRCFG_FULL_RESET,
base + PM_RSTC);- return 0;
+}
+static int bcm2835_wdt_start(struct udevice *dev, u64 timeout_ms, ulong flags) +{
- struct bcm2835_wdt_priv *priv = dev_get_priv(dev);
- priv->timeout_ticks = MS_TO_WDOG_TICKS(timeout_ms);
- if (priv->timeout_ticks > PM_WDOG_MAX_TICKS) {
printf("bcm2835_wdt: the timeout value is too high, using ~16s instead.\n");priv->timeout_ticks = PM_WDOG_MAX_TICKS;- }
- return bcm2835_wdt_start_ticks(dev, priv->timeout_ticks, flags);
+}
+static int bcm2835_wdt_reset(struct udevice *dev) +{
- struct bcm2835_wdt_priv *priv = dev_get_priv(dev);
- /* restart the timer with the value of priv->timeout_ticks
* saved from the last bcm2835_wdt_start() call.*/- return bcm2835_wdt_start_ticks(dev, priv->timeout_ticks, 0);
+}
+static int bcm2835_wdt_stop(struct udevice *dev) +{
- struct bcm2835_wdt_priv *priv = dev_get_priv(dev);
- void __iomem *base = priv->base;
- writel(PM_PASSWORD | PM_RSTC_RESET, base + PM_RSTC);
- return 0;
+}
+static int bcm2835_wdt_expire_now(struct udevice *dev, ulong flags) +{
- int ret;
- /* use a timeout of 10 ticks (~150us) */
- ret = bcm2835_wdt_start_ticks(dev, 10, flags);
- if (ret)
return ret;- mdelay(500);
- return 0;
+}
+static const struct wdt_ops bcm2835_wdt_ops = {
- .reset = bcm2835_wdt_reset,
- .start = bcm2835_wdt_start,
- .stop = bcm2835_wdt_stop,
- .expire_now = bcm2835_wdt_expire_now,
+};
+static const struct udevice_id bcm2835_wdt_ids[] = {
- { .compatible = "brcm,bcm2835-pm" },
- { .compatible = "brcm,bcm2835-pm-wdt" },
- { /* sentinel */ }
+};
+static int bcm2835_wdt_probe(struct udevice *dev) +{
- struct bcm2835_wdt_priv *priv = dev_get_priv(dev);
- priv->base = dev_remap_addr(dev);
- if (!priv->base)
return -EINVAL;- priv->timeout_ticks = PM_WDOG_MAX_TICKS;
- bcm2835_wdt_stop(dev);
- return 0;
+}
+U_BOOT_DRIVER(bcm2835_wdt) = {
- .name = "bcm2835_wdt",
- .id = UCLASS_WDT,
- .of_match = bcm2835_wdt_ids,
- .probe = bcm2835_wdt_probe,
- .priv_auto = sizeof(struct bcm2835_wdt_priv),
- .ops = &bcm2835_wdt_ops,
+};
Viele Grüße, Stefan Roese