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Diffstat (limited to 'arch/arm64/kernel/psci.c')
-rw-r--r--arch/arm64/kernel/psci.c244
1 files changed, 136 insertions, 108 deletions
diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c
index ea18cb53921e..869f202748e8 100644
--- a/arch/arm64/kernel/psci.c
+++ b/arch/arm64/kernel/psci.c
@@ -15,7 +15,6 @@
#define pr_fmt(fmt) "psci: " fmt
-#include <linux/acpi.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/smp.h>
@@ -25,8 +24,8 @@
#include <linux/slab.h>
#include <uapi/linux/psci.h>
-#include <asm/acpi.h>
#include <asm/compiler.h>
+#include <asm/cputype.h>
#include <asm/cpu_ops.h>
#include <asm/errno.h>
#include <asm/psci.h>
@@ -37,16 +36,31 @@
#define PSCI_POWER_STATE_TYPE_STANDBY 0
#define PSCI_POWER_STATE_TYPE_POWER_DOWN 1
-struct psci_power_state {
- u16 id;
- u8 type;
- u8 affinity_level;
-};
+static bool psci_power_state_loses_context(u32 state)
+{
+ return state & PSCI_0_2_POWER_STATE_TYPE_MASK;
+}
+
+static bool psci_power_state_is_valid(u32 state)
+{
+ const u32 valid_mask = PSCI_0_2_POWER_STATE_ID_MASK |
+ PSCI_0_2_POWER_STATE_TYPE_MASK |
+ PSCI_0_2_POWER_STATE_AFFL_MASK;
+
+ return !(state & ~valid_mask);
+}
+
+/*
+ * The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
+ * calls to its resident CPU, so we must avoid issuing those. We never migrate
+ * a Trusted OS even if it claims to be capable of migration -- doing so will
+ * require cooperation with a Trusted OS driver.
+ */
+static int resident_cpu = -1;
struct psci_operations {
- int (*cpu_suspend)(struct psci_power_state state,
- unsigned long entry_point);
- int (*cpu_off)(struct psci_power_state state);
+ int (*cpu_suspend)(u32 state, unsigned long entry_point);
+ int (*cpu_off)(u32 state);
int (*cpu_on)(unsigned long cpuid, unsigned long entry_point);
int (*migrate)(unsigned long cpuid);
int (*affinity_info)(unsigned long target_affinity,
@@ -56,23 +70,21 @@ struct psci_operations {
static struct psci_operations psci_ops;
-static int (*invoke_psci_fn)(u64, u64, u64, u64);
-typedef int (*psci_initcall_t)(const struct device_node *);
-
-asmlinkage int __invoke_psci_fn_hvc(u64, u64, u64, u64);
-asmlinkage int __invoke_psci_fn_smc(u64, u64, u64, u64);
+typedef unsigned long (psci_fn)(unsigned long, unsigned long,
+ unsigned long, unsigned long);
+asmlinkage psci_fn __invoke_psci_fn_hvc;
+asmlinkage psci_fn __invoke_psci_fn_smc;
+static psci_fn *invoke_psci_fn;
enum psci_function {
PSCI_FN_CPU_SUSPEND,
PSCI_FN_CPU_ON,
PSCI_FN_CPU_OFF,
PSCI_FN_MIGRATE,
- PSCI_FN_AFFINITY_INFO,
- PSCI_FN_MIGRATE_INFO_TYPE,
PSCI_FN_MAX,
};
-static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state);
+static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state);
static u32 psci_function_id[PSCI_FN_MAX];
@@ -92,56 +104,28 @@ static int psci_to_linux_errno(int errno)
return -EINVAL;
}
-static u32 psci_power_state_pack(struct psci_power_state state)
-{
- return ((state.id << PSCI_0_2_POWER_STATE_ID_SHIFT)
- & PSCI_0_2_POWER_STATE_ID_MASK) |
- ((state.type << PSCI_0_2_POWER_STATE_TYPE_SHIFT)
- & PSCI_0_2_POWER_STATE_TYPE_MASK) |
- ((state.affinity_level << PSCI_0_2_POWER_STATE_AFFL_SHIFT)
- & PSCI_0_2_POWER_STATE_AFFL_MASK);
-}
-
-static void psci_power_state_unpack(u32 power_state,
- struct psci_power_state *state)
-{
- state->id = (power_state & PSCI_0_2_POWER_STATE_ID_MASK) >>
- PSCI_0_2_POWER_STATE_ID_SHIFT;
- state->type = (power_state & PSCI_0_2_POWER_STATE_TYPE_MASK) >>
- PSCI_0_2_POWER_STATE_TYPE_SHIFT;
- state->affinity_level =
- (power_state & PSCI_0_2_POWER_STATE_AFFL_MASK) >>
- PSCI_0_2_POWER_STATE_AFFL_SHIFT;
-}
-
-static int psci_get_version(void)
+static u32 psci_get_version(void)
{
- int err;
-
- err = invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
- return err;
+ return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
}
-static int psci_cpu_suspend(struct psci_power_state state,
- unsigned long entry_point)
+static int psci_cpu_suspend(u32 state, unsigned long entry_point)
{
int err;
- u32 fn, power_state;
+ u32 fn;
fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
- power_state = psci_power_state_pack(state);
- err = invoke_psci_fn(fn, power_state, entry_point, 0);
+ err = invoke_psci_fn(fn, state, entry_point, 0);
return psci_to_linux_errno(err);
}
-static int psci_cpu_off(struct psci_power_state state)
+static int psci_cpu_off(u32 state)
{
int err;
- u32 fn, power_state;
+ u32 fn;
fn = psci_function_id[PSCI_FN_CPU_OFF];
- power_state = psci_power_state_pack(state);
- err = invoke_psci_fn(fn, power_state, 0, 0);
+ err = invoke_psci_fn(fn, state, 0, 0);
return psci_to_linux_errno(err);
}
@@ -168,30 +152,29 @@ static int psci_migrate(unsigned long cpuid)
static int psci_affinity_info(unsigned long target_affinity,
unsigned long lowest_affinity_level)
{
- int err;
- u32 fn;
-
- fn = psci_function_id[PSCI_FN_AFFINITY_INFO];
- err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0);
- return err;
+ return invoke_psci_fn(PSCI_0_2_FN64_AFFINITY_INFO, target_affinity,
+ lowest_affinity_level, 0);
}
static int psci_migrate_info_type(void)
{
- int err;
- u32 fn;
+ return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
+}
- fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
- err = invoke_psci_fn(fn, 0, 0, 0);
- return err;
+static unsigned long psci_migrate_info_up_cpu(void)
+{
+ return invoke_psci_fn(PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU, 0, 0, 0);
}
-static int __maybe_unused cpu_psci_cpu_init_idle(struct device_node *cpu_node,
- unsigned int cpu)
+static int __maybe_unused cpu_psci_cpu_init_idle(unsigned int cpu)
{
int i, ret, count = 0;
- struct psci_power_state *psci_states;
- struct device_node *state_node;
+ u32 *psci_states;
+ struct device_node *state_node, *cpu_node;
+
+ cpu_node = of_get_cpu_node(cpu, NULL);
+ if (!cpu_node)
+ return -ENODEV;
/*
* If the PSCI cpu_suspend function hook has not been initialized
@@ -215,13 +198,13 @@ static int __maybe_unused cpu_psci_cpu_init_idle(struct device_node *cpu_node,
return -ENOMEM;
for (i = 0; i < count; i++) {
- u32 psci_power_state;
+ u32 state;
state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
ret = of_property_read_u32(state_node,
"arm,psci-suspend-param",
- &psci_power_state);
+ &state);
if (ret) {
pr_warn(" * %s missing arm,psci-suspend-param property\n",
state_node->full_name);
@@ -230,9 +213,13 @@ static int __maybe_unused cpu_psci_cpu_init_idle(struct device_node *cpu_node,
}
of_node_put(state_node);
- pr_debug("psci-power-state %#x index %d\n", psci_power_state,
- i);
- psci_power_state_unpack(psci_power_state, &psci_states[i]);
+ pr_debug("psci-power-state %#x index %d\n", state, i);
+ if (!psci_power_state_is_valid(state)) {
+ pr_warn("Invalid PSCI power state %#x\n", state);
+ ret = -EINVAL;
+ goto free_mem;
+ }
+ psci_states[i] = state;
}
/* Idle states parsed correctly, initialize per-cpu pointer */
per_cpu(psci_power_state, cpu) = psci_states;
@@ -275,6 +262,46 @@ static void psci_sys_poweroff(void)
invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
}
+/*
+ * Detect the presence of a resident Trusted OS which may cause CPU_OFF to
+ * return DENIED (which would be fatal).
+ */
+static void __init psci_init_migrate(void)
+{
+ unsigned long cpuid;
+ int type, cpu;
+
+ type = psci_ops.migrate_info_type();
+
+ if (type == PSCI_0_2_TOS_MP) {
+ pr_info("Trusted OS migration not required\n");
+ return;
+ }
+
+ if (type == PSCI_RET_NOT_SUPPORTED) {
+ pr_info("MIGRATE_INFO_TYPE not supported.\n");
+ return;
+ }
+
+ if (type != PSCI_0_2_TOS_UP_MIGRATE &&
+ type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
+ pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
+ return;
+ }
+
+ cpuid = psci_migrate_info_up_cpu();
+ if (cpuid & ~MPIDR_HWID_BITMASK) {
+ pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
+ cpuid);
+ return;
+ }
+
+ cpu = get_logical_index(cpuid);
+ resident_cpu = cpu >= 0 ? cpu : -1;
+
+ pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
+}
+
static void __init psci_0_2_set_functions(void)
{
pr_info("Using standard PSCI v0.2 function IDs\n");
@@ -290,11 +317,8 @@ static void __init psci_0_2_set_functions(void)
psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN64_MIGRATE;
psci_ops.migrate = psci_migrate;
- psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_0_2_FN64_AFFINITY_INFO;
psci_ops.affinity_info = psci_affinity_info;
- psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE] =
- PSCI_0_2_FN_MIGRATE_INFO_TYPE;
psci_ops.migrate_info_type = psci_migrate_info_type;
arm_pm_restart = psci_sys_reset;
@@ -307,32 +331,26 @@ static void __init psci_0_2_set_functions(void)
*/
static int __init psci_probe(void)
{
- int ver = psci_get_version();
-
- if (ver == PSCI_RET_NOT_SUPPORTED) {
- /*
- * PSCI versions >=0.2 mandates implementation of
- * PSCI_VERSION.
- */
- pr_err("PSCI firmware does not comply with the v0.2 spec.\n");
- return -EOPNOTSUPP;
- } else {
- pr_info("PSCIv%d.%d detected in firmware.\n",
- PSCI_VERSION_MAJOR(ver),
- PSCI_VERSION_MINOR(ver));
-
- if (PSCI_VERSION_MAJOR(ver) == 0 &&
- PSCI_VERSION_MINOR(ver) < 2) {
- pr_err("Conflicting PSCI version detected.\n");
- return -EINVAL;
- }
+ u32 ver = psci_get_version();
+
+ pr_info("PSCIv%d.%d detected in firmware.\n",
+ PSCI_VERSION_MAJOR(ver),
+ PSCI_VERSION_MINOR(ver));
+
+ if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {
+ pr_err("Conflicting PSCI version detected.\n");
+ return -EINVAL;
}
psci_0_2_set_functions();
+ psci_init_migrate();
+
return 0;
}
+typedef int (*psci_initcall_t)(const struct device_node *);
+
/*
* PSCI init function for PSCI versions >=0.2
*
@@ -421,6 +439,7 @@ int __init psci_dt_init(void)
return init_fn(np);
}
+#ifdef CONFIG_ACPI
/*
* We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
* explicitly clarified in SBBR
@@ -441,10 +460,11 @@ int __init psci_acpi_init(void)
return psci_probe();
}
+#endif
#ifdef CONFIG_SMP
-static int __init cpu_psci_cpu_init(struct device_node *dn, unsigned int cpu)
+static int __init cpu_psci_cpu_init(unsigned int cpu)
{
return 0;
}
@@ -469,11 +489,21 @@ static int cpu_psci_cpu_boot(unsigned int cpu)
}
#ifdef CONFIG_HOTPLUG_CPU
+static bool psci_tos_resident_on(int cpu)
+{
+ return cpu == resident_cpu;
+}
+
static int cpu_psci_cpu_disable(unsigned int cpu)
{
/* Fail early if we don't have CPU_OFF support */
if (!psci_ops.cpu_off)
return -EOPNOTSUPP;
+
+ /* Trusted OS will deny CPU_OFF */
+ if (psci_tos_resident_on(cpu))
+ return -EPERM;
+
return 0;
}
@@ -484,9 +514,8 @@ static void cpu_psci_cpu_die(unsigned int cpu)
* There are no known implementations of PSCI actually using the
* power state field, pass a sensible default for now.
*/
- struct psci_power_state state = {
- .type = PSCI_POWER_STATE_TYPE_POWER_DOWN,
- };
+ u32 state = PSCI_POWER_STATE_TYPE_POWER_DOWN <<
+ PSCI_0_2_POWER_STATE_TYPE_SHIFT;
ret = psci_ops.cpu_off(state);
@@ -498,7 +527,7 @@ static int cpu_psci_cpu_kill(unsigned int cpu)
int err, i;
if (!psci_ops.affinity_info)
- return 1;
+ return 0;
/*
* cpu_kill could race with cpu_die and we can
* potentially end up declaring this cpu undead
@@ -509,7 +538,7 @@ static int cpu_psci_cpu_kill(unsigned int cpu)
err = psci_ops.affinity_info(cpu_logical_map(cpu), 0);
if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) {
pr_info("CPU%d killed.\n", cpu);
- return 1;
+ return 0;
}
msleep(10);
@@ -518,15 +547,14 @@ static int cpu_psci_cpu_kill(unsigned int cpu)
pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n",
cpu, err);
- /* Make op_cpu_kill() fail. */
- return 0;
+ return -ETIMEDOUT;
}
#endif
#endif
static int psci_suspend_finisher(unsigned long index)
{
- struct psci_power_state *state = __this_cpu_read(psci_power_state);
+ u32 *state = __this_cpu_read(psci_power_state);
return psci_ops.cpu_suspend(state[index - 1],
virt_to_phys(cpu_resume));
@@ -535,7 +563,7 @@ static int psci_suspend_finisher(unsigned long index)
static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index)
{
int ret;
- struct psci_power_state *state = __this_cpu_read(psci_power_state);
+ u32 *state = __this_cpu_read(psci_power_state);
/*
* idle state index 0 corresponds to wfi, should never be called
* from the cpu_suspend operations
@@ -543,10 +571,10 @@ static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index)
if (WARN_ON_ONCE(!index))
return -EINVAL;
- if (state[index - 1].type == PSCI_POWER_STATE_TYPE_STANDBY)
+ if (!psci_power_state_loses_context(state[index - 1]))
ret = psci_ops.cpu_suspend(state[index - 1], 0);
else
- ret = __cpu_suspend(index, psci_suspend_finisher);
+ ret = cpu_suspend(index, psci_suspend_finisher);
return ret;
}