target/linux/generic/pending-4.19/341-MIPS-mm-remove-no-op-dma_map_ops-where-possible.patch

   1 From 203f17906ff45705fbdaa0430dbbc71142c2640f Mon Sep 17 00:00:00 2001
   2 From: Hauke Mehrtens <hauke@hauke-m.de>
   3 Date: Sat, 8 Dec 2018 21:45:53 +0100
   4 Subject: [PATCH 1/3] MIPS: Compile post DMA flush only when needed
   5
   6 dma_sync_phys() is only called for some CPUs when a mapping is removed.
   7 Add ARCH_HAS_SYNC_DMA_FOR_CPU only for the CPUs listed in
   8 cpu_needs_post_dma_flush() which need this extra call and do not compile
   9 this code in for other CPUs. We need this for R10000, R12000, BMIPS5000
  10 CPUs and CPUs supporting MAAR which was introduced in MIPS32r5.
  11
  12 This will hopefully improve the performance of the not affected devices.
  13
  14 Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
  15 ---
  16  arch/mips/Kconfig              | 6 +++++-
  17  arch/mips/mm/dma-noncoherent.c | 2 ++
  18  2 files changed, 7 insertions(+), 1 deletion(-)
  19
  20 --- a/arch/mips/Kconfig
  21 +++ b/arch/mips/Kconfig
  22 @@ -1116,7 +1116,6 @@ config DMA_PERDEV_COHERENT
  23  config DMA_NONCOHERENT
  24         bool
  25         select ARCH_HAS_SYNC_DMA_FOR_DEVICE
  26 -       select ARCH_HAS_SYNC_DMA_FOR_CPU
  27         select NEED_DMA_MAP_STATE
  28         select DMA_NONCOHERENT_MMAP
  29         select DMA_NONCOHERENT_CACHE_SYNC
  30 @@ -1897,9 +1896,11 @@ config SYS_HAS_CPU_MIPS32_R3_5
  31
  32  config SYS_HAS_CPU_MIPS32_R5
  33         bool
  34 +       select ARCH_HAS_SYNC_DMA_FOR_CPU
  35
  36  config SYS_HAS_CPU_MIPS32_R6
  37         bool
  38 +       select ARCH_HAS_SYNC_DMA_FOR_CPU
  39
  40  config SYS_HAS_CPU_MIPS64_R1
  41         bool
  42 @@ -1909,6 +1910,7 @@ config SYS_HAS_CPU_MIPS64_R2
  43
  44  config SYS_HAS_CPU_MIPS64_R6
  45         bool
  46 +       select ARCH_HAS_SYNC_DMA_FOR_CPU
  47
  48  config SYS_HAS_CPU_R3000
  49         bool
  50 @@ -1945,6 +1947,7 @@ config SYS_HAS_CPU_R8000
  51
  52  config SYS_HAS_CPU_R10000
  53         bool
  54 +       select ARCH_HAS_SYNC_DMA_FOR_CPU
  55
  56  config SYS_HAS_CPU_RM7000
  57         bool
  58 @@ -1973,6 +1976,7 @@ config SYS_HAS_CPU_BMIPS4380
  59  config SYS_HAS_CPU_BMIPS5000
  60         bool
  61         select SYS_HAS_CPU_BMIPS
  62 +       select ARCH_HAS_SYNC_DMA_FOR_CPU
  63
  64  config SYS_HAS_CPU_XLR
  65         bool
  66 --- a/arch/mips/mm/dma-noncoherent.c
  67 +++ b/arch/mips/mm/dma-noncoherent.c
  68 @@ -191,12 +191,14 @@ void arch_sync_dma_for_device(struct dev
  69                 dma_sync_phys(paddr, size, dir);
  70  }
  71
  72 +#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU
  73  void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
  74                 size_t size, enum dma_data_direction dir)
  75  {
  76         if (cpu_needs_post_dma_flush(dev))
  77                 dma_sync_phys(paddr, size, dir);
  78  }
  79 +#endif
  80
  81  void arch_dma_cache_sync(struct device *dev, void *vaddr, size_t size,
  82                 enum dma_data_direction direction)