Hi Stephan,

On 4/11/23 11:29, Stefan Roese wrote:

Hi Lionel,

On 4/5/23 11:53, Lionel Debieve wrote:

...

Implement a ARM SMCCC based driver that allow to use a secure watchdog on the platform.

Signed-off-by: Lionel Debieve lionel.debieve@foss.st.com Reviewed-by: Patrick Delaunay patrick.delaunay@foss.st.com Tested-by: Patrick Delaunay patrick.delaunay@foss.st.com

---

(no changes since v1)

Hmm, this does not seem to be correct. Could you please include the list of changed stuff here to make reviewing easier?

Thanks, sorry fir the change list, issue on my side with the patman options ;)

I'll just add a minor change regarding log_err in the probe and send a v3.

Thanks,

Br,

Lionel

Other than this:

Reviewed-by: Stefan Roese sr@denx.de

Thanks, Stefan

...

drivers/watchdog/Kconfig       |   8 +++   drivers/watchdog/Makefile      |   1 +   drivers/watchdog/arm_smc_wdt.c | 121 +++++++++++++++++++++++++++++++++   3 files changed, 130 insertions(+)   create mode 100644 drivers/watchdog/arm_smc_wdt.c

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index b5ac8f7f50d..3a0341f609d 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -352,6 +352,14 @@ config WDT_TANGIER         Intel Tangier SoC. If you're using a board with Intel Tangier         SoC, say Y here.   +config WDT_ARM_SMC +    bool "ARM SMC watchdog timer support" +    depends on WDT && ARM_SMCCC +    imply WATCHDOG +    help +      Select this to enable Arm SMC watchdog timer. This watchdog will manage +      a watchdog based on ARM SMCCC communication.

config SPL_WDT       bool "Enable driver model for watchdog timer drivers in SPL"       depends on SPL_DM diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 446d961d7d2..a4633c0d2fa 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -18,6 +18,7 @@ obj-$(CONFIG_$(SPL_TPL_)WDT) += wdt-uclass.o   obj-$(CONFIG_WDT_SANDBOX) += sandbox_wdt.o   obj-$(CONFIG_WDT_ALARM_SANDBOX) += sandbox_alarm-wdt.o   obj-$(CONFIG_WDT_APPLE) += apple_wdt.o +obj-$(CONFIG_WDT_ARM_SMC) += arm_smc_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 diff --git a/drivers/watchdog/arm_smc_wdt.c b/drivers/watchdog/arm_smc_wdt.c new file mode 100644 index 00000000000..70ab99bdbfb --- /dev/null +++ b/drivers/watchdog/arm_smc_wdt.c @@ -0,0 +1,121 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/*

• • ARM Secure Monitor Call watchdog driver
• • Copyright (C) 2022, STMicroelectronics - All Rights Reserved
• • This file is based on Linux driver drivers/watchdog/arm_smc_wdt.c
• */

+#define LOG_CATEGORY UCLASS_WDT

+#include <dm.h> +#include <dm/device_compat.h> +#include <linux/arm-smccc.h> +#include <linux/psci.h> +#include <wdt.h>

+#define DRV_NAME        "arm_smc_wdt"

+#define WDT_TIMEOUT_SECS(TIMEOUT)    ((TIMEOUT) / 1000)

+enum smcwd_call { +    SMCWD_INIT        = 0, +    SMCWD_SET_TIMEOUT    = 1, +    SMCWD_ENABLE        = 2, +    SMCWD_PET        = 3, +    SMCWD_GET_TIMELEFT    = 4, +};

+struct smcwd_priv_data { +    u32 smc_id; +    unsigned int min_timeout; +    unsigned int max_timeout; +};

+static int smcwd_call(struct udevice *dev, enum smcwd_call call, +              unsigned long arg, struct arm_smccc_res *res) +{ +    struct smcwd_priv_data *priv = dev_get_priv(dev); +    struct arm_smccc_res local_res;

+    if (!res) +        res = &local_res;

+    arm_smccc_smc(priv->smc_id, call, arg, 0, 0, 0, 0, 0, res);

+    if (res->a0 == PSCI_RET_NOT_SUPPORTED) +        return -ENODEV; +    if (res->a0 == PSCI_RET_INVALID_PARAMS) +        return -EINVAL; +    if (res->a0 != PSCI_RET_SUCCESS) +        return -EIO;

+    return 0; +}

+static int smcwd_reset(struct udevice *dev) +{ +    return smcwd_call(dev, SMCWD_PET, 0, NULL); +}

+static int smcwd_stop(struct udevice *dev) +{ +    return smcwd_call(dev, SMCWD_ENABLE, 0, NULL); +}

+static int smcwd_start(struct udevice *dev, u64 timeout_ms, ulong flags) +{ +    struct smcwd_priv_data *priv = dev_get_priv(dev); +    u64 timeout_sec = WDT_TIMEOUT_SECS(timeout_ms); +    int err;

+    if (timeout_sec < priv->min_timeout || timeout_sec > priv->max_timeout)    { +        dev_err(dev, "Timeout value not supported\n"); +        return -EINVAL; +    }

+    err = smcwd_call(dev, SMCWD_SET_TIMEOUT, timeout_sec, NULL); +    if (err) { +        dev_err(dev, "Timeout out configuration failed\n"); +        return err; +    }

+    return smcwd_call(dev, SMCWD_ENABLE, 1, NULL); +}

+static int smcwd_probe(struct udevice *dev) +{ +    struct smcwd_priv_data *priv = dev_get_priv(dev); +    struct arm_smccc_res res; +    int err;

+    priv->smc_id = dev_read_u32_default(dev, "arm,smc-id", 0x82003D06);

+    err = smcwd_call(dev, SMCWD_INIT, 0, &res); +    if (err < 0) +        return err;

+    priv->min_timeout = res.a1; +    priv->max_timeout = res.a2;

+    return 0; +}

+static const struct wdt_ops smcwd_ops = { +    .start        = smcwd_start, +    .stop        = smcwd_stop, +    .reset        = smcwd_reset, +};

+static const struct udevice_id smcwd_dt_ids[] = { +    { .compatible = "arm,smc-wdt" }, +    {} +};

+U_BOOT_DRIVER(wdt_sandbox) = { +    .name = "smcwd", +    .id = UCLASS_WDT, +    .of_match = smcwd_dt_ids, +    .priv_auto = sizeof(struct smcwd_priv_data), +    .probe = smcwd_probe, +    .ops = &smcwd_ops, +};

Viele Grüße, Stefan Roese