diff options
Diffstat (limited to 'arch/arm/kernel/psci.c')
-rw-r--r-- | arch/arm/kernel/psci.c | 49 |
1 files changed, 45 insertions, 4 deletions
diff --git a/arch/arm/kernel/psci.c b/arch/arm/kernel/psci.c index 36531643cc2c..0daf4f252284 100644 --- a/arch/arm/kernel/psci.c +++ b/arch/arm/kernel/psci.c @@ -17,6 +17,7 @@ #include <linux/init.h> #include <linux/of.h> +#include <linux/string.h> #include <asm/compiler.h> #include <asm/errno.h> @@ -26,6 +27,11 @@ struct psci_operations psci_ops; +/* Type of psci support. Currently can only be enabled or disabled */ +#define PSCI_SUP_DISABLED 0 +#define PSCI_SUP_ENABLED 1 + +static unsigned int psci; static int (*invoke_psci_fn)(u32, u32, u32, u32); enum psci_function { @@ -42,6 +48,7 @@ static u32 psci_function_id[PSCI_FN_MAX]; #define PSCI_RET_EOPNOTSUPP -1 #define PSCI_RET_EINVAL -2 #define PSCI_RET_EPERM -3 +#define PSCI_RET_EALREADYON -4 static int psci_to_linux_errno(int errno) { @@ -54,6 +61,8 @@ static int psci_to_linux_errno(int errno) return -EINVAL; case PSCI_RET_EPERM: return -EPERM; + case PSCI_RET_EALREADYON: + return -EAGAIN; }; return -EINVAL; @@ -158,15 +167,18 @@ static const struct of_device_id psci_of_match[] __initconst = { {}, }; -static int __init psci_init(void) +void __init psci_init(void) { struct device_node *np; const char *method; u32 id; + if (psci == PSCI_SUP_DISABLED) + return; + np = of_find_matching_node(NULL, psci_of_match); if (!np) - return 0; + return; pr_info("probing function IDs from device-tree\n"); @@ -206,6 +218,35 @@ static int __init psci_init(void) out_put_node: of_node_put(np); - return 0; + return; +} + +int __init psci_probe(void) +{ + struct device_node *np; + int ret = -ENODEV; + + if (psci == PSCI_SUP_ENABLED) { + np = of_find_matching_node(NULL, psci_of_match); + if (np) + ret = 0; + } + + of_node_put(np); + return ret; +} + +static int __init early_psci(char *val) +{ + int ret = 0; + + if (strcmp(val, "enable") == 0) + psci = PSCI_SUP_ENABLED; + else if (strcmp(val, "disable") == 0) + psci = PSCI_SUP_DISABLED; + else + ret = -EINVAL; + + return ret; } -early_initcall(psci_init); +early_param("psci", early_psci); |