From 3137f2e60098bccdf9b3a744747b06a96addab9e Mon Sep 17 00:00:00 2001 From: Dmitry Baryshkov Date: Mon, 26 Sep 2022 14:07:58 +0300 Subject: firmware/psci: Add debugfs support to ease debugging To ease debugging of PSCI supported features, add debugfs file called 'psci' describing PSCI and SMC CC versions, enabled features and options. Signed-off-by: Dmitry Baryshkov Reviewed-by: Mark Brown Reviewed-by: Ulf Hansson Link: https://lore.kernel.org/r/20220926110758.666922-1-dmitry.baryshkov@linaro.org' Signed-off-by: Arnd Bergmann --- drivers/firmware/psci/psci.c | 116 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 115 insertions(+), 1 deletion(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c index 1628f1edef4a..42cae0ba10e2 100644 --- a/drivers/firmware/psci/psci.c +++ b/drivers/firmware/psci/psci.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include #include @@ -326,12 +327,125 @@ static void psci_sys_poweroff(void) invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0); } -static int __init psci_features(u32 psci_func_id) +static int psci_features(u32 psci_func_id) { return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES, psci_func_id, 0, 0); } +#ifdef CONFIG_DEBUG_FS + +#define PSCI_ID(ver, _name) \ + { .fn = PSCI_##ver##_FN_##_name, .name = #_name, } +#define PSCI_ID_NATIVE(ver, _name) \ + { .fn = PSCI_FN_NATIVE(ver, _name), .name = #_name, } + +/* A table of all optional functions */ +static const struct { + u32 fn; + const char *name; +} psci_fn_ids[] = { + PSCI_ID_NATIVE(0_2, MIGRATE), + PSCI_ID(0_2, MIGRATE_INFO_TYPE), + PSCI_ID_NATIVE(0_2, MIGRATE_INFO_UP_CPU), + PSCI_ID(1_0, CPU_FREEZE), + PSCI_ID_NATIVE(1_0, CPU_DEFAULT_SUSPEND), + PSCI_ID_NATIVE(1_0, NODE_HW_STATE), + PSCI_ID_NATIVE(1_0, SYSTEM_SUSPEND), + PSCI_ID(1_0, SET_SUSPEND_MODE), + PSCI_ID_NATIVE(1_0, STAT_RESIDENCY), + PSCI_ID_NATIVE(1_0, STAT_COUNT), + PSCI_ID_NATIVE(1_1, SYSTEM_RESET2), + PSCI_ID(1_1, MEM_PROTECT), + PSCI_ID_NATIVE(1_1, MEM_PROTECT_CHECK_RANGE), +}; + +static int psci_debugfs_read(struct seq_file *s, void *data) +{ + int feature, type, i; + u32 ver; + + ver = psci_ops.get_version(); + seq_printf(s, "PSCIv%d.%d\n", + PSCI_VERSION_MAJOR(ver), + PSCI_VERSION_MINOR(ver)); + + /* PSCI_FEATURES is available only starting from 1.0 */ + if (PSCI_VERSION_MAJOR(ver) < 1) + return 0; + + feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID); + if (feature != PSCI_RET_NOT_SUPPORTED) { + ver = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0); + seq_printf(s, "SMC Calling Convention v%d.%d\n", + PSCI_VERSION_MAJOR(ver), + PSCI_VERSION_MINOR(ver)); + } else { + seq_puts(s, "SMC Calling Convention v1.0 is assumed\n"); + } + + feature = psci_features(PSCI_FN_NATIVE(0_2, CPU_SUSPEND)); + if (feature < 0) { + seq_printf(s, "PSCI_FEATURES(CPU_SUSPEND) error (%d)\n", feature); + } else { + seq_printf(s, "OSI is %ssupported\n", + (feature & BIT(0)) ? "" : "not "); + seq_printf(s, "%s StateID format is used\n", + (feature & BIT(1)) ? "Extended" : "Original"); + } + + type = psci_ops.migrate_info_type(); + if (type == PSCI_0_2_TOS_UP_MIGRATE || + type == PSCI_0_2_TOS_UP_NO_MIGRATE) { + unsigned long cpuid; + + seq_printf(s, "Trusted OS %smigrate capable\n", + type == PSCI_0_2_TOS_UP_NO_MIGRATE ? "not " : ""); + cpuid = psci_migrate_info_up_cpu(); + seq_printf(s, "Trusted OS resident on physical CPU 0x%lx (#%d)\n", + cpuid, resident_cpu); + } else if (type == PSCI_0_2_TOS_MP) { + seq_puts(s, "Trusted OS migration not required\n"); + } else { + if (type != PSCI_RET_NOT_SUPPORTED) + seq_printf(s, "MIGRATE_INFO_TYPE returned unknown type (%d)\n", type); + } + + for (i = 0; i < ARRAY_SIZE(psci_fn_ids); i++) { + feature = psci_features(psci_fn_ids[i].fn); + if (feature == PSCI_RET_NOT_SUPPORTED) + continue; + if (feature < 0) + seq_printf(s, "PSCI_FEATURES(%s) error (%d)\n", + psci_fn_ids[i].name, feature); + else + seq_printf(s, "%s is supported\n", psci_fn_ids[i].name); + } + + return 0; +} + +static int psci_debugfs_open(struct inode *inode, struct file *f) +{ + return single_open(f, psci_debugfs_read, NULL); +} + +static const struct file_operations psci_debugfs_ops = { + .owner = THIS_MODULE, + .open = psci_debugfs_open, + .release = single_release, + .read = seq_read, + .llseek = seq_lseek +}; + +static int __init psci_debugfs_init(void) +{ + return PTR_ERR_OR_ZERO(debugfs_create_file("psci", 0444, NULL, NULL, + &psci_debugfs_ops)); +} +late_initcall(psci_debugfs_init) +#endif + #ifdef CONFIG_CPU_IDLE static int psci_suspend_finisher(unsigned long state) { -- cgit