From 07c75d7a6b9eae24ab72c6eb2fbd39963775b0bf Mon Sep 17 00:00:00 2001 From: Vladimir Murzin Date: Wed, 28 Jun 2017 10:16:57 +0100 Subject: [PATCH] drivers: dma-mapping: allow dma_common_mmap() for NOMMU Currently, internals of dma_common_mmap() is compiled out if build is done for either NOMMU or target which explicitly says it does not have/want coherent DMA mmap. It turned out that dma_common_mmap() can be handy in NOMMU setup (at least for ARM). This patch converts exitent NOMMU targets to use ARCH_NO_COHERENT_DMA_MMAP, thus when CONFIG_MMU is gone from dma_common_mmap() their behaviour stays unchanged. ARM is not converted to ARCH_NO_COHERENT_DMA_MMAP because it 1) already has mmap callback which can handle (at some extent) NOMMU 2) already defines dummy pgprot_noncached() for NOMMU build. c6x and frv stay untouched since they already have ARCH_NO_COHERENT_DMA_MMAP. Cc: Steven Miao Cc: Geert Uytterhoeven Cc: Michal Simek Cc: Yoshinori Sato Cc: Rich Felker Cc: Chris Zankel Cc: Max Filippov Suggested-by: Christoph Hellwig Signed-off-by: Vladimir Murzin Tested-by: Benjamin Gaignard --- arch/blackfin/Kconfig | 1 + arch/m32r/Kconfig | 1 + arch/m68k/Kconfig | 1 + arch/microblaze/Kconfig | 1 + arch/sh/Kconfig | 1 + arch/xtensa/Kconfig | 1 + drivers/base/dma-mapping.c | 4 ++-- 7 files changed, 8 insertions(+), 2 deletions(-) diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig index 3c1bd640042a..89bdb8264305 100644 --- a/arch/blackfin/Kconfig +++ b/arch/blackfin/Kconfig @@ -41,6 +41,7 @@ config BLACKFIN select MODULES_USE_ELF_RELA select HAVE_DEBUG_STACKOVERFLOW select HAVE_NMI + select ARCH_NO_COHERENT_DMA_MMAP config GENERIC_CSUM def_bool y diff --git a/arch/m32r/Kconfig b/arch/m32r/Kconfig index 95474460b367..87cde1e4b38c 100644 --- a/arch/m32r/Kconfig +++ b/arch/m32r/Kconfig @@ -19,6 +19,7 @@ config M32R select HAVE_DEBUG_STACKOVERFLOW select CPU_NO_EFFICIENT_FFS select DMA_NOOP_OPS + select ARCH_NO_COHERENT_DMA_MMAP if !MMU config SBUS bool diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index d140206d5d29..5abb548f0e70 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -2,6 +2,7 @@ config M68K bool default y select ARCH_MIGHT_HAVE_PC_PARPORT if ISA + select ARCH_NO_COHERENT_DMA_MMAP if !MMU select HAVE_IDE select HAVE_AOUT if MMU select HAVE_DEBUG_BUGVERBOSE diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig index 85885a501dce..8ba7b7c01418 100644 --- a/arch/microblaze/Kconfig +++ b/arch/microblaze/Kconfig @@ -2,6 +2,7 @@ config MICROBLAZE def_bool y select ARCH_HAS_GCOV_PROFILE_ALL select ARCH_MIGHT_HAVE_PC_PARPORT + select ARCH_NO_COHERENT_DMA_MMAP if !MMU select ARCH_WANT_IPC_PARSE_VERSION select BUILDTIME_EXTABLE_SORT select CLKSRC_OF diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig index ee086958b2b2..640a85925060 100644 --- a/arch/sh/Kconfig +++ b/arch/sh/Kconfig @@ -2,6 +2,7 @@ config SUPERH def_bool y select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_MIGHT_HAVE_PC_PARPORT + select ARCH_NO_COHERENT_DMA_MMAP if !MMU select HAVE_PATA_PLATFORM select CLKDEV_LOOKUP select HAVE_IDE if HAS_IOPORT_MAP diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index f4126cf997a4..7ad6d77b2f22 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -3,6 +3,7 @@ config ZONE_DMA config XTENSA def_bool y + select ARCH_NO_COHERENT_DMA_MMAP if !MMU select ARCH_WANT_FRAME_POINTERS select ARCH_WANT_IPC_PARSE_VERSION select BUILDTIME_EXTABLE_SORT diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c index 10e7c022e8cf..ce1e02b567c3 100644 --- a/drivers/base/dma-mapping.c +++ b/drivers/base/dma-mapping.c @@ -227,7 +227,7 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, void *cpu_addr, dma_addr_t dma_addr, size_t size) { int ret = -ENXIO; -#if defined(CONFIG_MMU) && !defined(CONFIG_ARCH_NO_COHERENT_DMA_MMAP) +#ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP unsigned long user_count = vma_pages(vma); unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr)); @@ -244,7 +244,7 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, user_count << PAGE_SHIFT, vma->vm_page_prot); } -#endif /* CONFIG_MMU && !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */ +#endif /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */ return ret; } -- GitLab