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 <dmitry.baryshkov@xxxxxxxxxx>
---
Changes since v1:
- Extended the table to include MEM_PROTECT functions (noted by Mark
Brown)
- Switched to seq_puts where possible
- Changed S_IRUGO to 0444
---
drivers/firmware/psci/psci.c | 116 ++++++++++++++++++++++++++++++++++-
include/uapi/linux/psci.h | 14 +++++
2 files changed, 129 insertions(+), 1 deletion(-)
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 <linux/acpi.h>
#include <linux/arm-smccc.h>
#include <linux/cpuidle.h>
+#include <linux/debugfs.h>
#include <linux/errno.h>
#include <linux/linkage.h>
#include <linux/of.h>
@@ -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)
{
diff --git a/include/uapi/linux/psci.h b/include/uapi/linux/psci.h
index 2bf93c0d6354..3511095c2702 100644
--- a/include/uapi/linux/psci.h
+++ b/include/uapi/linux/psci.h
@@ -48,12 +48,26 @@
#define PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU PSCI_0_2_FN64(7)
#define PSCI_1_0_FN_PSCI_FEATURES PSCI_0_2_FN(10)
+#define PSCI_1_0_FN_CPU_FREEZE PSCI_0_2_FN(11)
+#define PSCI_1_0_FN_CPU_DEFAULT_SUSPEND PSCI_0_2_FN(12)
+#define PSCI_1_0_FN_NODE_HW_STATE PSCI_0_2_FN(13)
#define PSCI_1_0_FN_SYSTEM_SUSPEND PSCI_0_2_FN(14)
#define PSCI_1_0_FN_SET_SUSPEND_MODE PSCI_0_2_FN(15)
+#define PSCI_1_0_FN_STAT_RESIDENCY PSCI_0_2_FN(16)
+#define PSCI_1_0_FN_STAT_COUNT PSCI_0_2_FN(17)
+
#define PSCI_1_1_FN_SYSTEM_RESET2 PSCI_0_2_FN(18)
+#define PSCI_1_1_FN_MEM_PROTECT PSCI_0_2_FN(19)
+#define PSCI_1_1_FN_MEM_PROTECT_CHECK_RANGE PSCI_0_2_FN(19)
+#define PSCI_1_0_FN64_CPU_DEFAULT_SUSPEND PSCI_0_2_FN64(12)
+#define PSCI_1_0_FN64_NODE_HW_STATE PSCI_0_2_FN64(13)
#define PSCI_1_0_FN64_SYSTEM_SUSPEND PSCI_0_2_FN64(14)
+#define PSCI_1_0_FN64_STAT_RESIDENCY PSCI_0_2_FN64(16)
+#define PSCI_1_0_FN64_STAT_COUNT PSCI_0_2_FN64(17)
+
#define PSCI_1_1_FN64_SYSTEM_RESET2 PSCI_0_2_FN64(18)
+#define PSCI_1_1_FN64_MEM_PROTECT_CHECK_RANGE PSCI_0_2_FN64(19)
/* PSCI v0.2 power state encoding for CPU_SUSPEND function */
#define PSCI_0_2_POWER_STATE_ID_MASK 0xffff
--
2.35.1
