From: Igor Opaniuk igor.opaniuk@foundries.io
Adds support for: * PSCI_FEATURES, which was introduced in PSCI 1.0. This provides API that allows discovering whether a specific PSCI function is implemented and its features. * SYSTEM_RESET2, which was introduced in PSCI 1.1, which extends existing SYSTEM_RESET. It provides support for vendor-specific resets, providing reset_type as an additional param.
For additional details visit [1].
Implementations of some functions were borrowed from Linux PSCI driver code [2].
[1] https://developer.arm.com/documentation/den0022/latest/ [2] master/drivers/firmware/psci/psci.c
Signed-off-by: Igor Opaniuk igor.opaniuk@foundries.io ---
drivers/firmware/psci.c | 70 +++++++++++++++++++++++++++++++++++++++++ include/linux/psci.h | 3 ++ 2 files changed, 73 insertions(+)
diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c index 68953cc4f4..8416cd445f 100644 --- a/drivers/firmware/psci.c +++ b/drivers/firmware/psci.c @@ -13,6 +13,7 @@ #include <log.h> #include <dm/lists.h> #include <efi_loader.h> +#include <sysreset.h> #include <linux/delay.h> #include <linux/libfdt.h> #include <linux/arm-smccc.h> @@ -26,12 +27,26 @@ #define PSCI_METHOD_HVC 1 #define PSCI_METHOD_SMC 2
+/* + * While a 64-bit OS can make calls with SMC32 calling conventions, for some + * calls it is necessary to use SMC64 to pass or return 64-bit values. + * For such calls PSCI_FN_NATIVE(version, name) will choose the appropriate + * (native-width) function ID. + */ +#if defined(CONFIG_ARM64) +#define PSCI_FN_NATIVE(version, name) PSCI_##version##_FN64_##name +#else +#define PSCI_FN_NATIVE(version, name) PSCI_##version##_FN_##name +#endif + #if CONFIG_IS_ENABLED(EFI_LOADER) int __efi_runtime_data psci_method; #else int psci_method __attribute__ ((section(".data"))); #endif
+static bool reset2_supported; + unsigned long __efi_runtime invoke_psci_fn (unsigned long function_id, unsigned long arg0, unsigned long arg1, unsigned long arg2) @@ -53,6 +68,27 @@ unsigned long __efi_runtime invoke_psci_fn return res.a0; }
+static int psci_features(u32 psci_func_id) +{ + return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES, + psci_func_id, 0, 0); +} + +static u32 psci_0_2_get_version(void) +{ + return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0); +} + +static void psci_init_system_reset2(void) +{ + int ret; + + ret = psci_features(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2)); + + if (ret != PSCI_RET_NOT_SUPPORTED) + reset2_supported = true; +} + static int psci_bind(struct udevice *dev) { /* No SYSTEM_RESET support for PSCI 0.1 */ @@ -73,6 +109,7 @@ static int psci_bind(struct udevice *dev) static int psci_probe(struct udevice *dev) { const char *method; + u32 ver;
#if defined(CONFIG_ARM64) if (current_el() == 3) @@ -94,6 +131,16 @@ static int psci_probe(struct udevice *dev) return -EINVAL; }
+ ver = psci_0_2_get_version(); + + pr_debug("PSCIv%d.%d detected in firmware.\n", + PSCI_VERSION_MAJOR(ver), + PSCI_VERSION_MINOR(ver)); + + if (PSCI_VERSION_MAJOR(ver) >= 1) { + psci_init_system_reset2(); + } + return 0; }
@@ -141,6 +188,29 @@ void reset_misc(void) } #endif /* CONFIG_PSCI_RESET */
+void psci_sys_reset(u32 type) +{ + do_psci_probe(); + + if (type == SYSRESET_WARM && reset2_supported) { + /* + * reset_type[31] = 0 (architectural) + * reset_type[30:0] = 0 (SYSTEM_WARM_RESET) + * cookie = 0 (ignored by the implementation) + */ + invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), 0, 0, 0); + } else { + invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0); + } +} + +void psci_sys_poweroff(void) +{ + do_psci_probe(); + + invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0); +} + #ifdef CONFIG_CMD_POWEROFF int do_poweroff(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) { diff --git a/include/linux/psci.h b/include/linux/psci.h index 38edde3137..c78c1079a8 100644 --- a/include/linux/psci.h +++ b/include/linux/psci.h @@ -118,6 +118,9 @@ #ifdef CONFIG_ARM_PSCI_FW unsigned long invoke_psci_fn(unsigned long a0, unsigned long a1, unsigned long a2, unsigned long a3); +void psci_sys_reset(u32 type); +void psci_sys_poweroff(void); + #else static inline unsigned long invoke_psci_fn(unsigned long a0, unsigned long a1, unsigned long a2, unsigned long a3)