[V3 PATCH 2/5] arm64 : Introduce support for ACPI _CCA object
From: catalin.marinas@arm.com (Catalin Marinas)
Date: 2015-05-11 17:12:50
Also in:
linux-acpi, linux-crypto, lkml, netdev
On Thu, May 07, 2015 at 07:37:13PM -0500, Suravee Suthikulpanit wrote:
quoted hunk ↗ jump to hunk
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 4269dba..c7227e8 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig@@ -1,5 +1,6 @@ config ARM64 def_bool y + select ACPI_CCA_REQUIRED if ACPI select ACPI_GENERIC_GSI if ACPI select ACPI_REDUCED_HARDWARE_ONLY if ACPI select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE@@ -19,6 +20,7 @@ config ARM64 select ARM_GIC_V2M if PCI_MSI select ARM_GIC_V3 select ARM_GIC_V3_ITS if PCI_MSI + select ARM64_SUPPORT_ACPI_CCA_ZERO if ACPI
As per the other sub-thread, I don't think we need this option at all.
quoted hunk ↗ jump to hunk
diff --git a/arch/arm64/include/asm/dma-mapping.h b/arch/arm64/include/asm/dma-mapping.h index 9437e3d..f0d6d0b 100644 --- a/arch/arm64/include/asm/dma-mapping.h +++ b/arch/arm64/include/asm/dma-mapping.h@@ -18,6 +18,7 @@ #ifdef __KERNEL__ +#include <linux/acpi.h> #include <linux/types.h> #include <linux/vmalloc.h>@@ -28,13 +29,23 @@ #define DMA_ERROR_CODE (~(dma_addr_t)0) extern struct dma_map_ops *dma_ops; +extern struct dma_map_ops dummy_dma_ops; static inline struct dma_map_ops *__generic_dma_ops(struct device *dev) { - if (unlikely(!dev) || !dev->archdata.dma_ops) + if (unlikely(!dev)) return dma_ops; - else + else if (dev->archdata.dma_ops) return dev->archdata.dma_ops; + else if (acpi_disabled) + return dma_ops; + + /* + * When ACPI is enabled, if arch_set_dma_ops is not called, + * we will disable device DMA capability by setting it + * to dummy_dma_ops. + */ + return &dummy_dma_ops; }
The code looks fine to me but Arnd had some comments that I didn't fully understand (dropping dummy_map_ops in favour of simply setting dma_mask to NULL; I don't think the existing swiotlb ops would behave in a way that always return NULL). -- Catalin