From: Al Stone al.stone@linaro.org
Introduce one early parameters "off" and "force" for "acpi", acpi=off will be the default behavior for ARM64, so introduce acpi=force to enable ACPI on ARM64.
Disable ACPI before early parameters parsed, and enable it to pass "acpi=force" if people want use ACPI on ARM64. This ensures DT be the prefer one if ACPI table and DT both are provided at this moment.
Signed-off-by: Al Stone al.stone@linaro.org Signed-off-by: Graeme Gregory graeme.gregory@linaro.org Signed-off-by: Hanjun Guo hanjun.guo@linaro.org --- Documentation/kernel-parameters.txt | 3 ++- arch/arm64/include/asm/acpi.h | 9 +++++++++ arch/arm64/kernel/acpi.c | 17 +++++++++++++++++ arch/arm64/kernel/setup.c | 3 +++ 4 files changed, 31 insertions(+), 1 deletion(-)
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 5ae8608..2af0948 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -165,7 +165,7 @@ multipliers 'Kilo', 'Mega', and 'Giga', equalling 2^10, 2^20, and 2^30 bytes respectively. Such letter suffixes can also be entirely omitted.
- acpi= [HW,ACPI,X86] + acpi= [HW,ACPI,X86,ARM64] Advanced Configuration and Power Interface Format: { force | off | strict | noirq | rsdt } force -- enable ACPI if default was off @@ -175,6 +175,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. strictly ACPI specification compliant. rsdt -- prefer RSDT over (default) XSDT copy_dsdt -- copy DSDT to memory + For ARM64, ONLY "acpi=off" or "acpi=force" are available
See also Documentation/power/runtime_pm.txt, pci=noacpi
diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h index 8b837ab..496c33b 100644 --- a/arch/arm64/include/asm/acpi.h +++ b/arch/arm64/include/asm/acpi.h @@ -26,6 +26,13 @@ static inline void disable_acpi(void) acpi_noirq = 1; }
+static inline void enable_acpi(void) +{ + acpi_disabled = 0; + acpi_pci_disabled = 0; + acpi_noirq = 0; +} + /* * It's used from ACPI core in kdump to boot UP system with SMP kernel, * with this check the ACPI core will not override the CPU index @@ -40,6 +47,8 @@ static inline bool acpi_has_cpu_in_madt(void)
static inline void arch_fix_phys_package_id(int num, u32 slot) { }
+#else +static inline void disable_acpi(void) { } #endif /* CONFIG_ACPI */
#endif /*_ASM_ACPI_H*/ diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index 9252f72..39a1655 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -67,3 +67,20 @@ void __init acpi_boot_table_init(void) if (acpi_table_init()) disable_acpi(); } + +static int __init parse_acpi(char *arg) +{ + if (!arg) + return -EINVAL; + + /* "acpi=off" disables both ACPI table parsing and interpreter */ + if (strcmp(arg, "off") == 0) + disable_acpi(); + else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */ + enable_acpi(); + else + return -EINVAL; /* Core will print when we return error */ + + return 0; +} +early_param("acpi", parse_acpi); diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 5b05227..15621b9 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -60,6 +60,7 @@ #include <asm/memblock.h> #include <asm/psci.h> #include <asm/efi.h> +#include <asm/acpi.h>
unsigned int processor_id; EXPORT_SYMBOL(processor_id); @@ -384,6 +385,8 @@ void __init setup_arch(char **cmdline_p)
early_ioremap_init();
+ disable_acpi(); + parse_early_param();
efi_init();