x86-32: Introduce CONFIG_X86_DEV_DMA_OPS
32-bit x86 systems may need their own DMA operations, so add
a new config option, which is turned on for 64-bit systems. This
patch has no functional effect but it paves the way for supporting
the STA2x11 I/O Hub and possibly other chips.
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Link: http://lkml.kernel.org/r/f79fcc1a2e17ef942e1b798b92aac43a80202532.1333560789.git.rubini@gnudd.com
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 1d14cc6..07b412a 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -12,6 +12,7 @@
config X86_64
def_bool 64BIT
+ select X86_DEV_DMA_OPS
### Arch settings
config X86
@@ -2215,6 +2216,10 @@
bool
select STOP_MACHINE if SMP
+config X86_DEV_DMA_OPS
+ bool
+ depends on X86_64
+
source "net/Kconfig"
source "drivers/Kconfig"
diff --git a/arch/x86/include/asm/device.h b/arch/x86/include/asm/device.h
index 63a2a03..93e1c55 100644
--- a/arch/x86/include/asm/device.h
+++ b/arch/x86/include/asm/device.h
@@ -5,8 +5,8 @@
#ifdef CONFIG_ACPI
void *acpi_handle;
#endif
-#ifdef CONFIG_X86_64
-struct dma_map_ops *dma_ops;
+#ifdef CONFIG_X86_DEV_DMA_OPS
+ struct dma_map_ops *dma_ops;
#endif
#if defined(CONFIG_INTEL_IOMMU) || defined(CONFIG_AMD_IOMMU)
void *iommu; /* hook for IOMMU specific extension */
diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
index 4b4331d..09aa473 100644
--- a/arch/x86/include/asm/dma-mapping.h
+++ b/arch/x86/include/asm/dma-mapping.h
@@ -30,7 +30,7 @@
static inline struct dma_map_ops *get_dma_ops(struct device *dev)
{
-#ifdef CONFIG_X86_32
+#ifndef CONFIG_X86_DEV_DMA_OPS
return dma_ops;
#else
if (unlikely(!dev) || !dev->archdata.dma_ops)
