| Message ID | 20230724223057.1208122-5-quic_eberman@quicinc.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | Implement a PSCI SYSTEM_RESET2 reboot-mode driver | expand |
On 25/07/2023 00:30, Elliot Berman wrote: > PSCI implements a restart notifier for architectural defined resets. > The SYSTEM_RESET2 allows vendor firmware to define additional reset > types which could be mapped to the reboot reason. > > + > +static const struct of_device_id psci_vendor_reset_id_table[] = { > + { .compatible = "arm,psci-vendor-reset" }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, psci_vendor_reset_id_table); > + > +static struct platform_driver psci_vendor_reset_driver = { > + .probe = psci_vendor_reset_probe, > + .driver = { > + .name = "psci-vendor-reset", > + .of_match_table = of_match_ptr(psci_vendor_reset_id_table), Drop of_match_ptr() - it is useless and if used, then it must be balanced with conditional table. > + }, > +}; > +module_platform_driver(psci_vendor_reset_driver); > + Best regards, Krzysztof
On Mon, Jul 24, 2023 at 03:30:54PM -0700, Elliot Berman wrote: > PSCI implements a restart notifier for architectural defined resets. > The SYSTEM_RESET2 allows vendor firmware to define additional reset > types which could be mapped to the reboot reason. > > Implement a driver to wire the reboot-mode framework to make vendor > SYSTEM_RESET2 calls on reboot. > > Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> Do we need to skip the PSCI call from the existing PSCI restart notifier which gets called after your newly introduced callback from reboot mode notifier? Thanks, Pavan
On 7/26/2023 3:41 AM, Pavan Kondeti wrote: > On Mon, Jul 24, 2023 at 03:30:54PM -0700, Elliot Berman wrote: >> PSCI implements a restart notifier for architectural defined resets. >> The SYSTEM_RESET2 allows vendor firmware to define additional reset >> types which could be mapped to the reboot reason. >> >> Implement a driver to wire the reboot-mode framework to make vendor >> SYSTEM_RESET2 calls on reboot. >> >> Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> > > Do we need to skip the PSCI call from the existing PSCI restart notifier > which gets called after your newly introduced callback from reboot mode > notifier? > No need, the vendor SYSTEM_RESET2 call shouldn't return if the call worked. > Thanks, > Pavan
On Wed, Jul 26, 2023 at 10:19:01AM -0700, Elliot Berman wrote: > > > On 7/26/2023 3:41 AM, Pavan Kondeti wrote: > > On Mon, Jul 24, 2023 at 03:30:54PM -0700, Elliot Berman wrote: > > > PSCI implements a restart notifier for architectural defined resets. > > > The SYSTEM_RESET2 allows vendor firmware to define additional reset > > > types which could be mapped to the reboot reason. > > > > > > Implement a driver to wire the reboot-mode framework to make vendor > > > SYSTEM_RESET2 calls on reboot. > > > > > > Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> > > > > Do we need to skip the PSCI call from the existing PSCI restart notifier > > which gets called after your newly introduced callback from reboot mode > > notifier? > > > > No need, the vendor SYSTEM_RESET2 call shouldn't return if the call worked. > From the documentation of restart handlers, restarting from reboot notifiers may not be correct. Since you hooked it up with reboot-mode driver framework, you may restart the system much early before the actual machine restart kicks in. Pls check. Thanks, Pavan
diff --git a/MAINTAINERS b/MAINTAINERS index 2da4c5f1917b..214b14c1da63 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -16984,6 +16984,7 @@ L: linux-arm-kernel@lists.infradead.org (moderated for non-subscribers) S: Maintained F: Documentation/devicetree/bindings/power/reset/arm,psci-vendor-reset.yaml F: drivers/firmware/psci/ +F: drivers/power/reset/psci-vendor-reset.c F: include/linux/psci.h F: include/uapi/linux/psci.h diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c index d9629ff87861..6db73f9d2304 100644 --- a/drivers/firmware/psci/psci.c +++ b/drivers/firmware/psci/psci.c @@ -328,6 +328,15 @@ static struct notifier_block psci_sys_reset_nb = { .priority = 129, }; +void psci_vendor_sys_reset2(u32 reset_type, u32 cookie) +{ + if (psci_system_reset2_supported) + invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), + reset_type | BIT_ULL(31), + cookie, 0); +} +EXPORT_SYMBOL_GPL(psci_vendor_sys_reset2); + static void psci_sys_poweroff(void) { invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0); diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig index fff07b2bd77b..1474b9d51089 100644 --- a/drivers/power/reset/Kconfig +++ b/drivers/power/reset/Kconfig @@ -311,4 +311,13 @@ config POWER_MLXBF help This driver supports reset or low power mode handling for Mellanox BlueField. +config POWER_RESET_PSCI_VENDOR_RESET + tristate "PSCI Vendor SYSTEM_RESET2 driver" + depends on ARM64 || ARM || COMPILE_TEST + select ARM_PSCI_FW + select REBOOT_MODE + help + Say y/m here to enable driver to use Vendor SYSTEM_RESET2 types on + chips which have firmware implementing custom SYSTEM_RESET2 types. + endif diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile index d763e6735ee3..d09243966b74 100644 --- a/drivers/power/reset/Makefile +++ b/drivers/power/reset/Makefile @@ -37,3 +37,4 @@ obj-$(CONFIG_SYSCON_REBOOT_MODE) += syscon-reboot-mode.o obj-$(CONFIG_POWER_RESET_SC27XX) += sc27xx-poweroff.o obj-$(CONFIG_NVMEM_REBOOT_MODE) += nvmem-reboot-mode.o obj-$(CONFIG_POWER_MLXBF) += pwr-mlxbf.o +obj-$(CONFIG_POWER_RESET_PSCI_VENDOR_RESET) += psci-vendor-reset.o diff --git a/drivers/power/reset/psci-vendor-reset.c b/drivers/power/reset/psci-vendor-reset.c new file mode 100644 index 000000000000..95d027225185 --- /dev/null +++ b/drivers/power/reset/psci-vendor-reset.c @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: GPL-2.0-only +/** + * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/reboot-mode.h> +#include <linux/psci.h> + +static int psci_vendor_system_reset2(struct reboot_mode_driver *reboot, unsigned int magic) +{ + psci_vendor_sys_reset2(magic, 0); + + return NOTIFY_DONE; +} + +static int psci_vendor_reset_probe(struct platform_device *pdev) +{ + struct reboot_mode_driver *reboot; + + reboot = devm_kzalloc(&pdev->dev, sizeof(*reboot), GFP_KERNEL); + if (!reboot) + return -ENOMEM; + + reboot->write = psci_vendor_system_reset2; + + return devm_reboot_mode_register(&pdev->dev, reboot); +} + +static const struct of_device_id psci_vendor_reset_id_table[] = { + { .compatible = "arm,psci-vendor-reset" }, + { } +}; +MODULE_DEVICE_TABLE(of, psci_vendor_reset_id_table); + +static struct platform_driver psci_vendor_reset_driver = { + .probe = psci_vendor_reset_probe, + .driver = { + .name = "psci-vendor-reset", + .of_match_table = of_match_ptr(psci_vendor_reset_id_table), + }, +}; +module_platform_driver(psci_vendor_reset_driver); + +MODULE_DESCRIPTION("PSCI Vendor SYSTEM_RESET2 Driver"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/psci.h b/include/linux/psci.h index 4ca0060a3fc4..0c652c12e0a8 100644 --- a/include/linux/psci.h +++ b/include/linux/psci.h @@ -21,6 +21,8 @@ bool psci_power_state_is_valid(u32 state); int psci_set_osi_mode(bool enable); bool psci_has_osi_support(void); +void psci_vendor_sys_reset2(u32 reset_type, u32 cookie); + struct psci_operations { u32 (*get_version)(void); int (*cpu_suspend)(u32 state, unsigned long entry_point);
PSCI implements a restart notifier for architectural defined resets. The SYSTEM_RESET2 allows vendor firmware to define additional reset types which could be mapped to the reboot reason. Implement a driver to wire the reboot-mode framework to make vendor SYSTEM_RESET2 calls on reboot. Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> --- MAINTAINERS | 1 + drivers/firmware/psci/psci.c | 9 +++++ drivers/power/reset/Kconfig | 9 +++++ drivers/power/reset/Makefile | 1 + drivers/power/reset/psci-vendor-reset.c | 49 +++++++++++++++++++++++++ include/linux/psci.h | 2 + 6 files changed, 71 insertions(+) create mode 100644 drivers/power/reset/psci-vendor-reset.c