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author | Guo Ren <ren_guo@c-sky.com> | 2019-07-30 14:43:22 +0800 |
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committer | Guo Ren <ren_guo@c-sky.com> | 2019-07-31 11:05:25 +0800 |
commit | 7f80fe207de9602aaff028c79345caa68c90cd31 (patch) | |
tree | 4052003f821439f67f8be27a26c016075cf48e7d /arch/csky/include | |
parent | 81b23ba645e6b2b446093b2d927c261a17f7dee3 (diff) | |
download | linux-stable-7f80fe207de9602aaff028c79345caa68c90cd31.tar.gz linux-stable-7f80fe207de9602aaff028c79345caa68c90cd31.tar.bz2 linux-stable-7f80fe207de9602aaff028c79345caa68c90cd31.zip |
csky: Fixup dma_alloc_coherent with PAGE_SO attribute
This bug is from commit: 2b070ccdf8c0 (fixup abiv2 mmap(... O_SYNC)
failed). In that patch we remove the _PAGE_SO for memory noncache
mapping and this will cause problem when drivers use dma descriptors
to control the transcations without dma_w/rmb().
After referencing other archs' implementation, pgprot_writecombine is
introduced for mmap(... O_SYNC).
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Diffstat (limited to 'arch/csky/include')
-rw-r--r-- | arch/csky/include/asm/pgtable.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/csky/include/asm/pgtable.h b/arch/csky/include/asm/pgtable.h index c429a6f347de..fc19ba446d62 100644 --- a/arch/csky/include/asm/pgtable.h +++ b/arch/csky/include/asm/pgtable.h @@ -258,6 +258,16 @@ static inline pgprot_t pgprot_noncached(pgprot_t _prot) { unsigned long prot = pgprot_val(_prot); + prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED | _PAGE_SO; + + return __pgprot(prot); +} + +#define pgprot_writecombine pgprot_writecombine +static inline pgprot_t pgprot_writecombine(pgprot_t _prot) +{ + unsigned long prot = pgprot_val(_prot); + prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED; return __pgprot(prot); |