From: Al Stone al.stone@linaro.org
ACPI reduced hardware mode is disabled by default, but ARM64 can only run properly in ACPI hardware reduced mode, so select ACPI_REDUCED_HARDWARE_ONLY if ACPI is enabled on ARM64.
If the firmware is not using hardware reduced ACPI mode, we will disable ACPI to avoid nightmare such as accessing some registers which are not available on ARM64.
CC: Catalin Marinas catalin.marinas@arm.com CC: Will Deacon will.deacon@arm.com Reviewed-by: Grant Likely grant.likely@linaro.org Tested-by: Suravee Suthikulpanit Suravee.Suthikulpanit@amd.com Tested-by: Yijing Wang wangyijing@huawei.com Tested-by: Mark Langsdorf mlangsdo@redhat.com Tested-by: Jon Masters jcm@redhat.com Tested-by: Timur Tabi timur@codeaurora.org Tested-by: Robert Richter rrichter@cavium.com Acked-by: Robert Richter rrichter@cavium.com Signed-off-by: Al Stone al.stone@linaro.org Signed-off-by: Hanjun Guo hanjun.guo@linaro.org --- arch/arm64/Kconfig | 1 + arch/arm64/kernel/acpi.c | 8 +++++++- 2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 1b8e973..d00ab9a 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1,5 +1,6 @@ config ARM64 def_bool y + select ACPI_REDUCED_HARDWARE_ONLY if ACPI select ARCH_BINFMT_ELF_RANDOMIZE_PIE select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE select ARCH_HAS_GCOV_PROFILE_ALL diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index 6468f88..5819ef7 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -303,6 +303,11 @@ static int __init acpi_parse_fadt(struct acpi_table_header *table) */ if (table->revision > 5 || (table->revision == 5 && fadt->minor_revision >= 1)) { + if (!acpi_gbl_reduced_hardware) { + pr_err("Not hardware reduced ACPI mode, will not be supported\n"); + goto disable_acpi; + } + /* * ACPI 5.1 only has two explicit methods to boot up SMP, * PSCI and Parking protocol, but the Parking protocol is @@ -319,8 +324,9 @@ static int __init acpi_parse_fadt(struct acpi_table_header *table)
pr_warn("Unsupported FADT revision %d.%d, should be 5.1+, will disable ACPI\n", table->revision, fadt->minor_revision); - disable_acpi();
+disable_acpi: + disable_acpi(); return -EINVAL; }