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authorLinus Torvalds <torvalds@linux-foundation.org>2015-06-24 19:02:15 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-24 19:02:15 +0200
commite3d8238d7f5c3f539a29f5ac596cd342d847e099 (patch)
treef545e6064155d0e943dcfbfabb3de60530a8e5de /arch/arm64/kernel/psci.c
parentMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm (diff)
parentarm64: use private ratelimit state along with show_unhandled_signals (diff)
downloadlinux-e3d8238d7f5c3f539a29f5ac596cd342d847e099.tar.xz
linux-e3d8238d7f5c3f539a29f5ac596cd342d847e099.zip
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas: "Mostly refactoring/clean-up: - CPU ops and PSCI (Power State Coordination Interface) refactoring following the merging of the arm64 ACPI support, together with handling of Trusted (secure) OS instances - Using fixmap for permanent FDT mapping, removing the initial dtb placement requirements (within 512MB from the start of the kernel image). This required moving the FDT self reservation out of the memreserve processing - Idmap (1:1 mapping used for MMU on/off) handling clean-up - Removing flush_cache_all() - not safe on ARM unless the MMU is off. Last stages of CPU power down/up are handled by firmware already - "Alternatives" (run-time code patching) refactoring and support for immediate branch patching, GICv3 CPU interface access - User faults handling clean-up And some fixes: - Fix for VDSO building with broken ELF toolchains - Fix another case of init_mm.pgd usage for user mappings (during ASID roll-over broadcasting) - Fix for FPSIMD reloading after CPU hotplug - Fix for missing syscall trace exit - Workaround for .inst asm bug - Compat fix for switching the user tls tpidr_el0 register" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (42 commits) arm64: use private ratelimit state along with show_unhandled_signals arm64: show unhandled SP/PC alignment faults arm64: vdso: work-around broken ELF toolchains in Makefile arm64: kernel: rename __cpu_suspend to keep it aligned with arm arm64: compat: print compat_sp instead of sp arm64: mm: Fix freeing of the wrong memmap entries with !SPARSEMEM_VMEMMAP arm64: entry: fix context tracking for el0_sp_pc arm64: defconfig: enable memtest arm64: mm: remove reference to tlb.S from comment block arm64: Do not attempt to use init_mm in reset_context() arm64: KVM: Switch vgic save/restore to alternative_insn arm64: alternative: Introduce feature for GICv3 CPU interface arm64: psci: fix !CONFIG_HOTPLUG_CPU build warning arm64: fix bug for reloading FPSIMD state after CPU hotplug. arm64: kernel thread don't need to save fpsimd context. arm64: fix missing syscall trace exit arm64: alternative: Work around .inst assembler bugs arm64: alternative: Merge alternative-asm.h into alternative.h arm64: alternative: Allow immediate branch as alternative instruction arm64: Rework alternate sequence for ARM erratum 845719 ...
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;
}