On 04/29/2015 09:04 AM, Catalin Marinas wrote:
On Wed, Apr 29, 2015 at 08:44:08AM -0500, Suravee Suthikulpanit wrote:
From ACPIv6 (http://www.uefi.org/sites/default/files/resources/ACPI_6.0.pdf), section 6.2.17 _CCA states that ARM platforms require ACPI _CCA object to be specified for DMA-cabpable devices. This patch introduces ACPI_MUST_HAVE_CCA in arm and arm64 Kconfig to specify such requirement.
Note that when _CCA is required, if it is missing in the DSDT. ACPI driver will default to setting up devices as non-coherent.
Signed-off-by: Mark Salter msalter@redhat.com Signed-off-by: Suravee Suthikulpanit Suravee.Suthikulpanit@amd.com
arch/arm/Kconfig | 1 + arch/arm64/Kconfig | 1 + drivers/acpi/Kconfig | 3 +++ 3 files changed, 5 insertions(+)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 45df48b..2a0d036 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1,6 +1,7 @@ config ARM bool default y
- select ACPI_MUST_HAVE_CCA if ACPI select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE select ARCH_HAS_ELF_RANDOMIZE select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
Any plans for ACPI on 32-bit ARM?
Not that I am aware, but I could be totally wrong. The reason I am adding this here for 32-bit ARM is because the ACPI spec mentioned this.
If you think this is not necessary until we introduce ACPI for ARM32, it can be removed.
Thanks,
Suravee