The memory allocated for the atomic pool needs to have the same
mapping attributes that we use for remapping, so use
pgprot_dmacoherent instead of open coding it. Also deduct a
suitable zone to allocate the memory from based on the presence
of the DMA zones.
Signed-off-by: Christoph Hellwig <hch@lst.de>
DMA_FROM_DEVICE only need to read dma data of memory into CPU cache,
so there is no need to clear cache before. Also clear + inv for
DMA_FROM_DEVICE won't cause problem, because the memory range for dma
won't be touched by software during dma working.
Changes for V2:
- Remove clr cache and ignore the DMA_TO_DEVICE in _for_cpu.
- Change inv to wbinv cache with DMA_FROM_DEVICE in _for_device.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
If the paddr and size are cross between NORMAL_ZONE and HIGHMEM_ZONE
memory range, cache_op will panic in do_page_fault with bad_area.
Optimize the code to support the range which cross memory ZONEs.
Changes for V2:
- Revert back to postcore_initcall
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
The csky code was largely copied from arm/arm64, so switch to the
generic arm64-based implementation instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Guo Ren <ren_guo@c-sky.com>
csky does not implement ZONE_DMA, which means passing GFP_DMA is a no-op.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Guo Ren <ren_guo@c-sky.com>
This patch adds files related to memory management and here is our
memory-layout:
Fixmap : 0xffc02000 – 0xfffff000 (4 MB - 12KB)
Pkmap : 0xff800000 – 0xffc00000 (4 MB)
Vmalloc : 0xf0200000 – 0xff000000 (238 MB)
Lowmem : 0x80000000 – 0xc0000000 (1GB)
abiv1 CPU (CK610) is VIPT cache and it doesn't support highmem.
abiv2 CPUs are all PIPT cache and they could support highmem.
Lowmem is directly mapped by msa0 & msa1 reg, and we needn't setup
memory page table for it.
Link:https://lore.kernel.org/lkml/20180518215548.GH17671@n2100.armlinux.org.uk/
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
