diff options
Diffstat (limited to 'arch/arm64/kernel/psci.c')
| -rw-r--r-- | arch/arm64/kernel/psci.c | 112 |
1 files changed, 79 insertions, 33 deletions
diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index 9b8a70ae64a1..ea18cb53921e 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -15,6 +15,7 @@ #define pr_fmt(fmt) "psci: " fmt +#include <linux/acpi.h> #include <linux/init.h> #include <linux/of.h> #include <linux/smp.h> @@ -24,6 +25,7 @@ #include <linux/slab.h> #include <uapi/linux/psci.h> +#include <asm/acpi.h> #include <asm/compiler.h> #include <asm/cpu_ops.h> #include <asm/errno.h> @@ -273,39 +275,8 @@ static void psci_sys_poweroff(void) invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0); } -/* - * PSCI Function IDs for v0.2+ are well defined so use - * standard values. - */ -static int __init psci_0_2_init(struct device_node *np) +static void __init psci_0_2_set_functions(void) { - int err, ver; - - err = get_set_conduit_method(np); - - if (err) - goto out_put_node; - - ver = psci_get_version(); - - if (ver == PSCI_RET_NOT_SUPPORTED) { - /* PSCI v0.2 mandates implementation of PSCI_ID_VERSION. */ - pr_err("PSCI firmware does not comply with the v0.2 spec.\n"); - err = -EOPNOTSUPP; - goto out_put_node; - } 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) { - err = -EINVAL; - pr_err("Conflicting PSCI version detected.\n"); - goto out_put_node; - } - } - pr_info("Using standard PSCI v0.2 function IDs\n"); psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN64_CPU_SUSPEND; psci_ops.cpu_suspend = psci_cpu_suspend; @@ -329,6 +300,60 @@ static int __init psci_0_2_init(struct device_node *np) 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) +{ + 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; + } + } + + psci_0_2_set_functions(); + + return 0; +} + +/* + * 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); @@ -381,7 +406,7 @@ static const struct of_device_id psci_of_match[] __initconst = { {}, }; -int __init psci_init(void) +int __init psci_dt_init(void) { struct device_node *np; const struct of_device_id *matched_np; @@ -396,6 +421,27 @@ int __init psci_init(void) return init_fn(np); } +/* + * 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(); +} + #ifdef CONFIG_SMP static int __init cpu_psci_cpu_init(struct device_node *dn, unsigned int cpu) |