[PATCH v2] watchdog: add amlogic watchdog support

Stefan Roese sr at denx.de
Thu Jul 21 17:33:04 CEST 2022


On 24.06.22 15:28, Neil Armstrong wrote:
> On 24/06/2022 12:20, Stefan Roese wrote:
>> Hi Neil,
>>
>> On 21.06.22 11:17, Neil Armstrong wrote:
>>> Hi Stefan,
>>>
>>> On 20/06/2022 16:55, Stefan Roese wrote:
>>>> On 13.06.22 16:00, Philippe Boos wrote:
>>>>> Add support for hardware watchdog timer for Amlogic SoCs.
>>>>> This driver has been heavily inspired by his Linux equivalent
>>>>> (meson_gxbb_wdt.c).
>>>>>
>>>>> Reviewed-by: Jerome Brunet <jbrunet at baylibre.com>
>>>>> Reviewed-by: Neil Armstrong <narmstrong at baylibre.com>
>>>>>
>>>>> Signed-off-by: Philippe Boos <pboos at baylibre.com>
>>>>>
>>>>
>>>> Reviewed-by: Stefan Roese <sr at denx.de>
>>>
>>> Should I take it into my tree ?
>>
>> I would have pushed it via my watchdog tree, after the merge-window has
>> been opened. But you can also push it via your tree, if you have some
>> dependencies or prefer this somehow. Feel free, to handle this in the
>> way you prefer. ;)
> 
> I have no dependencies to handle, feel free to take it :-)

Applied to u-boot-watchdog/master

Thanks,
Stefan

> Thanks,
> Neil
> 
>>
>> Thanks,
>> Stefan
>>
>>> Thanks,
>>> Neil
>>>
>>>>
>>>> Thanks,
>>>> Stefan
>>>>
>>>>> ---
>>>>>
>>>>> Your recommendations have been implemented. I let you check this 
>>>>> version 2.
>>>>> The reset works well when triggered by the wdt command in u-boot.
>>>>>
>>>>> This watchdog driver has been tested on a GXL libretech-cc board 
>>>>> and also on
>>>>> a custom G12a board. I did the following test cases:
>>>>>   * boot with a faulty boot command, then we reach watchdog reset 
>>>>> successfully,
>>>>>   * boot a Linux kernel with and without watchdog support, and 
>>>>> check if it is
>>>>>     working as expected.
>>>>>
>>>>>
>>>>>   MAINTAINERS                       |   1 +
>>>>>   doc/board/amlogic/index.rst       |   2 +
>>>>>   drivers/watchdog/Kconfig          |   7 ++
>>>>>   drivers/watchdog/Makefile         |   1 +
>>>>>   drivers/watchdog/meson_gxbb_wdt.c | 136 
>>>>> ++++++++++++++++++++++++++++++
>>>>>   5 files changed, 147 insertions(+)
>>>>>   create mode 100644 drivers/watchdog/meson_gxbb_wdt.c
>>>>>
>>>>> diff --git a/MAINTAINERS b/MAINTAINERS
>>>>> index 28e4d38238..ab3ef041f7 100644
>>>>> --- a/MAINTAINERS
>>>>> +++ b/MAINTAINERS
>>>>> @@ -160,6 +160,7 @@ F:    drivers/spi/meson_spifc.c
>>>>>   F:    drivers/pinctrl/meson/
>>>>>   F:    drivers/power/domain/meson-gx-pwrc-vpu.c
>>>>>   F:    drivers/video/meson/
>>>>> +F:    drivers/watchdog/meson_gxbb_wdt.c
>>>>>   F:    include/configs/meson64.h
>>>>>   F:    include/configs/meson64_android.h
>>>>>   F:    doc/board/amlogic/
>>>>> diff --git a/doc/board/amlogic/index.rst b/doc/board/amlogic/index.rst
>>>>> index 9c7fadf2c0..cc2ba50889 100644
>>>>> --- a/doc/board/amlogic/index.rst
>>>>> +++ b/doc/board/amlogic/index.rst
>>>>> @@ -73,6 +73,8 @@ This matrix concerns the actual source code version.
>>>>> +-------------------------------+-----------+-----------------+--------------+-------------+------------+-------------+--------------+ 
>>>>>
>>>>>   | PCIe (+NVMe)                  | *N/A*     | *N/A*           | 
>>>>> *N/A*        | **Yes**     | **Yes**    | **Yes**     | **Yes**      |
>>>>> +-------------------------------+-----------+-----------------+--------------+-------------+------------+-------------+--------------+ 
>>>>>
>>>>> +| Watchdog                      | *N/A*     | **Yes**         | 
>>>>> *N/A*        | *N/A*       | *N/A*      | *N/A*       | *N/A*        |
>>>>> ++-------------------------------+-----------+-----------------+--------------+-------------+------------+-------------+--------------+ 
>>>>>
>>>>>   Boot Documentation
>>>>>   ------------------
>>>>> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
>>>>> index c3eb8a8aec..da0fa5396f 100644
>>>>> --- a/drivers/watchdog/Kconfig
>>>>> +++ b/drivers/watchdog/Kconfig
>>>>> @@ -175,6 +175,13 @@ config WDT_MAX6370
>>>>>       help
>>>>>         Select this to enable max6370 watchdog timer.
>>>>> +config WDT_MESON_GXBB
>>>>> +    bool "Amlogic watchdog timer support"
>>>>> +    depends on WDT
>>>>> +    help
>>>>> +      Select this to enable Meson watchdog timer,
>>>>> +      which can be found on some Amlogic platforms.
>>>>> +
>>>>>   config WDT_MPC8xx
>>>>>       bool "MPC8xx watchdog timer support"
>>>>>       depends on WDT && MPC8xx
>>>>> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
>>>>> index 1f6199beca..0e2f582a5f 100644
>>>>> --- a/drivers/watchdog/Makefile
>>>>> +++ b/drivers/watchdog/Makefile
>>>>> @@ -27,6 +27,7 @@ obj-$(CONFIG_WDT_ORION) += orion_wdt.o
>>>>>   obj-$(CONFIG_WDT_CDNS) += cdns_wdt.o
>>>>>   obj-$(CONFIG_WDT_GPIO) += gpio_wdt.o
>>>>>   obj-$(CONFIG_WDT_MAX6370) += max6370_wdt.o
>>>>> +obj-$(CONFIG_WDT_MESON_GXBB) += meson_gxbb_wdt.o
>>>>>   obj-$(CONFIG_WDT_MPC8xx) += mpc8xx_wdt.o
>>>>>   obj-$(CONFIG_WDT_MT7620) += mt7620_wdt.o
>>>>>   obj-$(CONFIG_WDT_MT7621) += mt7621_wdt.o
>>>>> diff --git a/drivers/watchdog/meson_gxbb_wdt.c 
>>>>> b/drivers/watchdog/meson_gxbb_wdt.c
>>>>> new file mode 100644
>>>>> index 0000000000..6ab005813f
>>>>> --- /dev/null
>>>>> +++ b/drivers/watchdog/meson_gxbb_wdt.c
>>>>> @@ -0,0 +1,136 @@
>>>>> +// SPDX-License-Identifier: GPL-2.0+
>>>>> +/*
>>>>> + * Copyright (c) 2022 BayLibre, SAS.
>>>>> + */
>>>>> +
>>>>> +#include <clk.h>
>>>>> +#include <dm.h>
>>>>> +#include <dm/device_compat.h>
>>>>> +#include <reset.h>
>>>>> +#include <wdt.h>
>>>>> +#include <asm/io.h>
>>>>> +#include <linux/bitops.h>
>>>>> +
>>>>> +#define GXBB_WDT_CTRL_REG            0x0
>>>>> +#define GXBB_WDT_TCNT_REG            0x8
>>>>> +#define GXBB_WDT_RSET_REG            0xc
>>>>> +
>>>>> +#define GXBB_WDT_CTRL_SYS_RESET_NOW        BIT(26)
>>>>> +#define GXBB_WDT_CTRL_CLKDIV_EN            BIT(25)
>>>>> +#define GXBB_WDT_CTRL_CLK_EN            BIT(24)
>>>>> +#define GXBB_WDT_CTRL_EE_RESET            BIT(21)
>>>>> +#define GXBB_WDT_CTRL_EN            BIT(18)
>>>>> +
>>>>> +#define GXBB_WDT_CTRL_DIV_MASK            GENMASK(17, 0)
>>>>> +#define GXBB_WDT_TCNT_SETUP_MASK        GENMASK(15, 0)
>>>>> +
>>>>> +
>>>>> +struct amlogic_wdt_priv {
>>>>> +    void __iomem *reg_base;
>>>>> +};
>>>>> +
>>>>> +static int amlogic_wdt_set_timeout(struct udevice *dev, u64 
>>>>> timeout_ms)
>>>>> +{
>>>>> +    struct amlogic_wdt_priv *data = dev_get_priv(dev);
>>>>> +
>>>>> +    if (timeout_ms > GXBB_WDT_TCNT_SETUP_MASK) {
>>>>> +        dev_warn(dev, "%s: timeout_ms=%llu: maximum watchdog 
>>>>> timeout exceeded\n",
>>>>> +                 __func__, timeout_ms);
>>>>> +        timeout_ms = GXBB_WDT_TCNT_SETUP_MASK;
>>>>> +    }
>>>>> +
>>>>> +    writel(timeout_ms, data->reg_base + GXBB_WDT_TCNT_REG);
>>>>> +
>>>>> +    return 0;
>>>>> +}
>>>>> +
>>>>> +static int amlogic_wdt_stop(struct udevice *dev)
>>>>> +{
>>>>> +    struct amlogic_wdt_priv *data = dev_get_priv(dev);
>>>>> +
>>>>> +    writel(readl(data->reg_base + GXBB_WDT_CTRL_REG) & 
>>>>> ~GXBB_WDT_CTRL_EN,
>>>>> +           data->reg_base + GXBB_WDT_CTRL_REG);
>>>>> +
>>>>> +    return 0;
>>>>> +}
>>>>> +
>>>>> +static int amlogic_wdt_start(struct udevice *dev, u64 time_ms, 
>>>>> ulong flags)
>>>>> +{
>>>>> +    struct amlogic_wdt_priv *data = dev_get_priv(dev);
>>>>> +
>>>>> +    writel(readl(data->reg_base + GXBB_WDT_CTRL_REG) | 
>>>>> GXBB_WDT_CTRL_EN,
>>>>> +           data->reg_base + GXBB_WDT_CTRL_REG);
>>>>> +
>>>>> +    return amlogic_wdt_set_timeout(dev, time_ms);
>>>>> +}
>>>>> +
>>>>> +static int amlogic_wdt_reset(struct udevice *dev)
>>>>> +{
>>>>> +    struct amlogic_wdt_priv *data = dev_get_priv(dev);
>>>>> +
>>>>> +    writel(0, data->reg_base + GXBB_WDT_RSET_REG);
>>>>> +
>>>>> +    return 0;
>>>>> +}
>>>>> +
>>>>> +static int amlogic_wdt_expire_now(struct udevice *dev, ulong flags)
>>>>> +{
>>>>> +    struct amlogic_wdt_priv *data = dev_get_priv(dev);
>>>>> +
>>>>> +    writel(0, data->reg_base + GXBB_WDT_CTRL_SYS_RESET_NOW);
>>>>> +
>>>>> +    return 0;
>>>>> +}
>>>>> +
>>>>> +static int amlogic_wdt_probe(struct udevice *dev)
>>>>> +{
>>>>> +    struct amlogic_wdt_priv *data = dev_get_priv(dev);
>>>>> +    int ret;
>>>>> +
>>>>> +    data->reg_base = dev_remap_addr(dev);
>>>>> +    if (!data->reg_base)
>>>>> +        return -EINVAL;
>>>>> +
>>>>> +    struct clk clk;
>>>>> +
>>>>> +    ret = clk_get_by_index(dev, 0, &clk);
>>>>> +    if (ret)
>>>>> +        return ret;
>>>>> +
>>>>> +    ret = clk_enable(&clk);
>>>>> +    if (ret) {
>>>>> +        clk_free(&clk);
>>>>> +        return ret;
>>>>> +    }
>>>>> +
>>>>> +    /* Setup with 1ms timebase */
>>>>> +    writel(((clk_get_rate(&clk) / 1000) & GXBB_WDT_CTRL_DIV_MASK) |
>>>>> +           GXBB_WDT_CTRL_EE_RESET |
>>>>> +           GXBB_WDT_CTRL_CLK_EN |
>>>>> +           GXBB_WDT_CTRL_CLKDIV_EN,
>>>>> +           data->reg_base + GXBB_WDT_CTRL_REG);
>>>>> +
>>>>> +    return 0;
>>>>> +}
>>>>> +
>>>>> +static const struct wdt_ops amlogic_wdt_ops = {
>>>>> +    .start = amlogic_wdt_start,
>>>>> +    .reset = amlogic_wdt_reset,
>>>>> +    .stop = amlogic_wdt_stop,
>>>>> +    .expire_now = amlogic_wdt_expire_now,
>>>>> +};
>>>>> +
>>>>> +static const struct udevice_id amlogic_wdt_ids[] = {
>>>>> +    { .compatible = "amlogic,meson-gxbb-wdt" },
>>>>> +    {}
>>>>> +};
>>>>> +
>>>>> +U_BOOT_DRIVER(amlogic_wdt) = {
>>>>> +    .name = "amlogic_wdt",
>>>>> +    .id = UCLASS_WDT,
>>>>> +    .of_match = amlogic_wdt_ids,
>>>>> +    .priv_auto = sizeof(struct amlogic_wdt_priv),
>>>>> +    .probe = amlogic_wdt_probe,
>>>>> +    .ops = &amlogic_wdt_ops,
>>>>> +    .flags = DM_FLAG_PRE_RELOC,
>>>>> +};
>>>>
>>>> Viele Grüße,
>>>> Stefan Roese
>>>>
>>>
>>
>> Viele Grüße,
>> Stefan Roese
>>
> 

Viele Grüße,
Stefan Roese

-- 
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HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
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