The watchdog controller on the Meson-A/C series SoCs is moved to secure world,
We have to call SMC instruction to trap the ATF for watchdog operation. These
operations are different from previous SoCs, so we introduce a new watchdog
driver to support this kind of SoCs.
Changes since v5 at [4]:
- take the wdt node as child node of secure-monitor
- update dt-binding description
- invoke of_platform_default_populate() instantiate wdt device according to Rob's suggestion at [5]
- find the secure-monitor node through the wdt parent node instead of of_find_compatible_node()
- add Guenter's Reviewed-by
Changes since v4 at [3]:
- add watchdog node in dts, and introduce a new optional property "timeout-sec"
- add dt-binding for meson secure watchdog
- instantiate wdt device through dts node instead of platform_device_register_simple()
Changes since v3 at [2]:
- add SM_A1_ prefix for WATCHDOG_OPS
- remove phandle to secure-monitor node
- remove watchdog node from dts, and register wdt device by platform_device_register_simple()
- remove dt-binding for meson secure watchdog
- use the msec as unit of timeout parameter which is passed to fw side
Changes since v2 at [1]:
- remove useless dependency in Kconfig
- return zero when getting left time value fails
Changes since v1 at [0]:
- add a new dependency in Kconfig
- simplify/add the return operation
- remove useless ping operation when setting the timeout
- fix some return values
- fix the license statement
[0]:https://lore.kernel.org/linux-amlogic/[email protected]
[1]:https://lore.kernel.org/linux-amlogic/[email protected]
[2]:https://lore.kernel.org/linux-amlogic/[email protected]
[3]:https://lore.kernel.org/linux-amlogic/[email protected]
[4]:https://lore.kernel.org/linux-amlogic/[email protected]
[5]:https://patchwork.kernel.org/patch/11288017
Xingyu Chen (5):
firmware: meson_sm: add new SMC ID support for accessing secure
watchdog
firmware: meson_sm: populate platform device based on the child node
dt-bindings: watchdog: add new binding for meson secure watchdog
watchdog: add meson secure watchdog driver
arm64: dts: a1: add secure watchdog controller
.../bindings/watchdog/amlogic,meson-sec-wdt.yaml | 40 +++++
arch/arm64/boot/dts/amlogic/meson-a1.dtsi | 6 +
drivers/firmware/meson/meson_sm.c | 3 +
drivers/watchdog/Kconfig | 16 ++
drivers/watchdog/Makefile | 1 +
drivers/watchdog/meson_sec_wdt.c | 185 +++++++++++++++++++++
include/linux/firmware/meson/meson_sm.h | 1 +
7 files changed, 252 insertions(+)
create mode 100644 Documentation/devicetree/bindings/watchdog/amlogic,meson-sec-wdt.yaml
create mode 100644 drivers/watchdog/meson_sec_wdt.c
--
2.7.4
The child node of secure-monitor cann't be populated as platform device
automatically during the kernel initialization phase, so we invoke
of_platform_default_populate() to do it.
Signed-off-by: Xingyu Chen <[email protected]>
---
drivers/firmware/meson/meson_sm.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/firmware/meson/meson_sm.c b/drivers/firmware/meson/meson_sm.c
index 8cdd405..d2b1e76 100644
--- a/drivers/firmware/meson/meson_sm.c
+++ b/drivers/firmware/meson/meson_sm.c
@@ -310,6 +310,8 @@ static int __init meson_sm_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, fw);
+ of_platform_default_populate(dev->of_node, NULL, dev);
+
pr_info("secure-monitor enabled\n");
if (sysfs_create_group(&pdev->dev.kobj, &meson_sm_sysfs_attr_group))
--
2.7.4
The new SMC ID is used to access secure registers by meson secure
watchdog driver.
Signed-off-by: Xingyu Chen <[email protected]>
---
drivers/firmware/meson/meson_sm.c | 1 +
include/linux/firmware/meson/meson_sm.h | 1 +
2 files changed, 2 insertions(+)
diff --git a/drivers/firmware/meson/meson_sm.c b/drivers/firmware/meson/meson_sm.c
index 1d5b4d7..8cdd405 100644
--- a/drivers/firmware/meson/meson_sm.c
+++ b/drivers/firmware/meson/meson_sm.c
@@ -44,6 +44,7 @@ static const struct meson_sm_chip gxbb_chip = {
CMD(SM_EFUSE_WRITE, 0x82000031),
CMD(SM_EFUSE_USER_MAX, 0x82000033),
CMD(SM_GET_CHIP_ID, 0x82000044),
+ CMD(SM_A1_WATCHDOG_OPS, 0x82000086),
{ /* sentinel */ },
},
};
diff --git a/include/linux/firmware/meson/meson_sm.h b/include/linux/firmware/meson/meson_sm.h
index 6669e2a..9ef1524 100644
--- a/include/linux/firmware/meson/meson_sm.h
+++ b/include/linux/firmware/meson/meson_sm.h
@@ -12,6 +12,7 @@ enum {
SM_EFUSE_WRITE,
SM_EFUSE_USER_MAX,
SM_GET_CHIP_ID,
+ SM_A1_WATCHDOG_OPS,
};
struct meson_sm_firmware;
--
2.7.4