[PATCH] ARM: dma-mapping: remove unconditional dependency on CMA
From: m.szyprowski@samsung.com (Marek Szyprowski)
Date: 2012-05-30 09:00:12
Also in:
lkml
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
CMA has been enabled unconditionally on all ARMv6+ systems to solve the long standing issue of double kernel mappings for all dma coherent buffers. This however created a dependency on CONFIG_EXPERIMENTAL for the whole ARM architecture what should be really avoided. This patch removes this dependency and lets one use old, well-tested dma-mapping implementation also on ARMv6+ systems without the need to use EXPERIMENTAL stuff. Reported-by: Russell King <redacted> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> --- arch/arm/Kconfig | 1 - arch/arm/mm/dma-mapping.c | 10 ++++------ 2 files changed, 4 insertions(+), 7 deletions(-)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 5e76013..ca7354f 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig@@ -7,7 +7,6 @@ config ARM select HAVE_IDE if PCI || ISA || PCMCIA select HAVE_DMA_ATTRS select HAVE_DMA_CONTIGUOUS if (CPU_V6 || CPU_V6K || CPU_V7) - select CMA if (CPU_V6 || CPU_V6K || CPU_V7) select HAVE_MEMBLOCK select RTC_LIB select SYS_SUPPORTS_APM_EMULATION
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index ea6b431..106c4c0 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c@@ -268,10 +268,8 @@ static int __init consistent_init(void) unsigned long base = consistent_base; unsigned long num_ptes = (CONSISTENT_END - base) >> PMD_SHIFT; -#ifndef CONFIG_ARM_DMA_USE_IOMMU - if (cpu_architecture() >= CPU_ARCH_ARMv6) + if (IS_ENABLED(CONFIG_CMA) && !IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU)) return 0; -#endif consistent_pte = kmalloc(num_ptes * sizeof(pte_t), GFP_KERNEL); if (!consistent_pte) {
@@ -342,7 +340,7 @@ static int __init coherent_init(void) struct page *page; void *ptr; - if (cpu_architecture() < CPU_ARCH_ARMv6) + if (!IS_ENABLED(CONFIG_CMA)) return 0; ptr = __alloc_from_contiguous(NULL, size, prot, &page);
@@ -704,7 +702,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, if (arch_is_coherent() || nommu()) addr = __alloc_simple_buffer(dev, size, gfp, &page); - else if (cpu_architecture() < CPU_ARCH_ARMv6) + else if (!IS_ENABLED(CONFIG_CMA)) addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, caller); else if (gfp & GFP_ATOMIC) addr = __alloc_from_pool(dev, size, &page, caller);
@@ -773,7 +771,7 @@ void arm_dma_free(struct device *dev, size_t size, void *cpu_addr, if (arch_is_coherent() || nommu()) { __dma_free_buffer(page, size); - } else if (cpu_architecture() < CPU_ARCH_ARMv6) { + } else if (!IS_ENABLED(CONFIG_CMA)) { __dma_free_remap(cpu_addr, size); __dma_free_buffer(page, size); } else {
--
1.7.1.569.g6f426