[PATCH v2] watchdog: add amlogic watchdog support
Neil Armstrong
narmstrong at baylibre.com
Fri Jun 24 15:28:23 CEST 2022
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 :-)
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
>
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