summaryrefslogtreecommitdiffstats
path: root/drivers/firmware/psci.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2015-09-03 16:27:01 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-09-03 16:27:01 -0700
commitc706c7eb0d08098f0d768aeef945d7cf1f8858b4 (patch)
treec629c9705514b70dd3e8f8dc67fa8d849871886c /drivers/firmware/psci.c
parent79b0691d0c1d3d4a976e3304a1512e6eca9671ec (diff)
parent3ff32a0def6e0d2e21a6c5ad1b00726592774018 (diff)
downloadlinux-c706c7eb0d08098f0d768aeef945d7cf1f8858b4.tar.bz2
Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM development updates from Russell King: "Included in this update: - moving PSCI code from ARM64/ARM to drivers/ - removal of some architecture internals from global kernel view - addition of software based "privileged no access" support using the old domains register to turn off the ability for kernel loads/stores to access userspace. Only the proper accessors will be usable. - addition of early fixup support for early console - re-addition (and reimplementation) of OMAP special interconnect barrier - removal of finish_arch_switch() - only expose cpuX/online in sysfs if hotpluggable - a number of code cleanups" * 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (41 commits) ARM: software-based priviledged-no-access support ARM: entry: provide uaccess assembly macro hooks ARM: entry: get rid of multiple macro definitions ARM: 8421/1: smp: Collapse arch_cpu_idle_dead() into cpu_die() ARM: uaccess: provide uaccess_save_and_enable() and uaccess_restore() ARM: mm: improve do_ldrd_abort macro ARM: entry: ensure that IRQs are enabled when calling syscall_trace_exit() ARM: entry: efficiency cleanups ARM: entry: get rid of asm_trace_hardirqs_on_cond ARM: uaccess: simplify user access assembly ARM: domains: remove DOMAIN_TABLE ARM: domains: keep vectors in separate domain ARM: domains: get rid of manager mode for user domain ARM: domains: move initial domain setting value to asm/domains.h ARM: domains: provide domain_mask() ARM: domains: switch to keeping domain value in register ARM: 8419/1: dma-mapping: harmonize definition of DMA_ERROR_CODE ARM: 8417/1: refactor bitops functions with BIT_MASK() and BIT_WORD() ARM: 8416/1: Feroceon: use of_iomap() to map register base ARM: 8415/1: early fixmap support for earlycon ...
Diffstat (limited to 'drivers/firmware/psci.c')
-rw-r--r--drivers/firmware/psci.c382
1 files changed, 382 insertions, 0 deletions
diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c
new file mode 100644
index 000000000000..42700f09a8c5
--- /dev/null
+++ b/drivers/firmware/psci.c
@@ -0,0 +1,382 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2015 ARM Limited
+ */
+
+#define pr_fmt(fmt) "psci: " fmt
+
+#include <linux/errno.h>
+#include <linux/linkage.h>
+#include <linux/of.h>
+#include <linux/pm.h>
+#include <linux/printk.h>
+#include <linux/psci.h>
+#include <linux/reboot.h>
+
+#include <uapi/linux/psci.h>
+
+#include <asm/cputype.h>
+#include <asm/system_misc.h>
+#include <asm/smp_plat.h>
+
+/*
+ * 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_0_2_FN_NATIVE(x) will choose the appropriate (native-width)
+ * function ID.
+ */
+#ifdef CONFIG_64BIT
+#define PSCI_0_2_FN_NATIVE(name) PSCI_0_2_FN64_##name
+#else
+#define PSCI_0_2_FN_NATIVE(name) PSCI_0_2_FN_##name
+#endif
+
+/*
+ * 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;
+
+bool psci_tos_resident_on(int cpu)
+{
+ return cpu == resident_cpu;
+}
+
+struct psci_operations psci_ops;
+
+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_MAX,
+};
+
+static u32 psci_function_id[PSCI_FN_MAX];
+
+static int psci_to_linux_errno(int errno)
+{
+ switch (errno) {
+ case PSCI_RET_SUCCESS:
+ return 0;
+ case PSCI_RET_NOT_SUPPORTED:
+ return -EOPNOTSUPP;
+ case PSCI_RET_INVALID_PARAMS:
+ return -EINVAL;
+ case PSCI_RET_DENIED:
+ return -EPERM;
+ };
+
+ return -EINVAL;
+}
+
+static u32 psci_get_version(void)
+{
+ return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
+}
+
+static int psci_cpu_suspend(u32 state, unsigned long entry_point)
+{
+ int err;
+ u32 fn;
+
+ fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
+ err = invoke_psci_fn(fn, state, entry_point, 0);
+ return psci_to_linux_errno(err);
+}
+
+static int psci_cpu_off(u32 state)
+{
+ int err;
+ u32 fn;
+
+ fn = psci_function_id[PSCI_FN_CPU_OFF];
+ err = invoke_psci_fn(fn, state, 0, 0);
+ return psci_to_linux_errno(err);
+}
+
+static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
+{
+ int err;
+ u32 fn;
+
+ fn = psci_function_id[PSCI_FN_CPU_ON];
+ err = invoke_psci_fn(fn, cpuid, entry_point, 0);
+ return psci_to_linux_errno(err);
+}
+
+static int psci_migrate(unsigned long cpuid)
+{
+ int err;
+ u32 fn;
+
+ fn = psci_function_id[PSCI_FN_MIGRATE];
+ err = invoke_psci_fn(fn, cpuid, 0, 0);
+ return psci_to_linux_errno(err);
+}
+
+static int psci_affinity_info(unsigned long target_affinity,
+ unsigned long lowest_affinity_level)
+{
+ return invoke_psci_fn(PSCI_0_2_FN_NATIVE(AFFINITY_INFO),
+ target_affinity, lowest_affinity_level, 0);
+}
+
+static int psci_migrate_info_type(void)
+{
+ return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
+}
+
+static unsigned long psci_migrate_info_up_cpu(void)
+{
+ return invoke_psci_fn(PSCI_0_2_FN_NATIVE(MIGRATE_INFO_UP_CPU),
+ 0, 0, 0);
+}
+
+static int get_set_conduit_method(struct device_node *np)
+{
+ const char *method;
+
+ pr_info("probing for conduit method from DT.\n");
+
+ if (of_property_read_string(np, "method", &method)) {
+ pr_warn("missing \"method\" property\n");
+ return -ENXIO;
+ }
+
+ if (!strcmp("hvc", method)) {
+ invoke_psci_fn = __invoke_psci_fn_hvc;
+ } else if (!strcmp("smc", method)) {
+ invoke_psci_fn = __invoke_psci_fn_smc;
+ } else {
+ pr_warn("invalid \"method\" property: %s\n", method);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
+{
+ invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
+}
+
+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 = -1;
+
+ 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");
+ psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN_NATIVE(CPU_SUSPEND);
+ psci_ops.cpu_suspend = psci_cpu_suspend;
+
+ psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
+ psci_ops.cpu_off = psci_cpu_off;
+
+ psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN_NATIVE(CPU_ON);
+ psci_ops.cpu_on = psci_cpu_on;
+
+ psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN_NATIVE(MIGRATE);
+ psci_ops.migrate = psci_migrate;
+
+ psci_ops.affinity_info = psci_affinity_info;
+
+ psci_ops.migrate_info_type = psci_migrate_info_type;
+
+ arm_pm_restart = psci_sys_reset;
+
+ pm_power_off = psci_sys_poweroff;
+}
+
+/*
+ * Probe function for PSCI firmware versions >= 0.2
+ */
+static int __init psci_probe(void)
+{
+ 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
+ *
+ * Probe based on PSCI PSCI_VERSION function
+ */
+static int __init psci_0_2_init(struct device_node *np)
+{
+ int err;
+
+ err = get_set_conduit_method(np);
+
+ if (err)
+ goto out_put_node;
+ /*
+ * Starting with v0.2, the PSCI specification introduced a call
+ * (PSCI_VERSION) that allows probing the firmware version, so
+ * that PSCI function IDs and version specific initialization
+ * can be carried out according to the specific version reported
+ * by firmware
+ */
+ err = psci_probe();
+
+out_put_node:
+ of_node_put(np);
+ return err;
+}
+
+/*
+ * PSCI < v0.2 get PSCI Function IDs via DT.
+ */
+static int __init psci_0_1_init(struct device_node *np)
+{
+ u32 id;
+ int err;
+
+ err = get_set_conduit_method(np);
+
+ if (err)
+ goto out_put_node;
+
+ pr_info("Using PSCI v0.1 Function IDs from DT\n");
+
+ if (!of_property_read_u32(np, "cpu_suspend", &id)) {
+ psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
+ psci_ops.cpu_suspend = psci_cpu_suspend;
+ }
+
+ if (!of_property_read_u32(np, "cpu_off", &id)) {
+ psci_function_id[PSCI_FN_CPU_OFF] = id;
+ psci_ops.cpu_off = psci_cpu_off;
+ }
+
+ if (!of_property_read_u32(np, "cpu_on", &id)) {
+ psci_function_id[PSCI_FN_CPU_ON] = id;
+ psci_ops.cpu_on = psci_cpu_on;
+ }
+
+ if (!of_property_read_u32(np, "migrate", &id)) {
+ psci_function_id[PSCI_FN_MIGRATE] = id;
+ psci_ops.migrate = psci_migrate;
+ }
+
+out_put_node:
+ of_node_put(np);
+ return err;
+}
+
+static const struct of_device_id const psci_of_match[] __initconst = {
+ { .compatible = "arm,psci", .data = psci_0_1_init},
+ { .compatible = "arm,psci-0.2", .data = psci_0_2_init},
+ {},
+};
+
+int __init psci_dt_init(void)
+{
+ struct device_node *np;
+ const struct of_device_id *matched_np;
+ psci_initcall_t init_fn;
+
+ np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
+
+ if (!np)
+ return -ENODEV;
+
+ init_fn = (psci_initcall_t)matched_np->data;
+ 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
+ */
+int __init psci_acpi_init(void)
+{
+ if (!acpi_psci_present()) {
+ pr_info("is not implemented in ACPI.\n");
+ return -EOPNOTSUPP;
+ }
+
+ pr_info("probing for conduit method from ACPI.\n");
+
+ if (acpi_psci_use_hvc())
+ invoke_psci_fn = __invoke_psci_fn_hvc;
+ else
+ invoke_psci_fn = __invoke_psci_fn_smc;
+
+ return psci_probe();
+}
+#endif