-From: Felix Fietkau <nbd@nbd.name>
-Date: Tue, 5 Dec 2017 12:46:01 +0100
-Subject: [PATCH] MIPS: mm: remove no-op dma_map_ops where possible
+From 203f17906ff45705fbdaa0430dbbc71142c2640f Mon Sep 17 00:00:00 2001
+From: Hauke Mehrtens <hauke@hauke-m.de>
+Date: Sat, 8 Dec 2018 21:45:53 +0100
+Subject: [PATCH 1/3] MIPS: Compile post DMA flush only when needed
-If no post-DMA flush is required, and the platform does not provide
-plat_unmap_dma_mem(), there is no need to include unmap or sync_for_cpu
-ops.
+dma_sync_phys() is only called for some CPUs when a mapping is removed.
+Add ARCH_HAS_SYNC_DMA_FOR_CPU only for the CPUs listed in
+cpu_needs_post_dma_flush() which need this extra call and do not compile
+this code in for other CPUs. We need this for R10000, R12000, BMIPS5000
+CPUs and CPUs supporting MAAR which was introduced in MIPS32r5.
-With this patch they are compiled out to improve icache footprint
-on devices that handle lots of DMA traffic (especially network routers).
+This will hopefully improve the performance of the not affected devices.
-Signed-off-by: Felix Fietkau <nbd@nbd.name>
+Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
---
+ arch/mips/Kconfig | 6 +++++-
+ arch/mips/mm/dma-noncoherent.c | 2 ++
+ 2 files changed, 7 insertions(+), 1 deletion(-)
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
-@@ -221,6 +221,7 @@ config BMIPS_GENERIC
- select BRCMSTB_L2_IRQ
- select IRQ_MIPS_CPU
- select DMA_NONCOHERENT
-+ select DMA_UNMAP_POST_FLUSH
- select SYS_SUPPORTS_32BIT_KERNEL
- select SYS_SUPPORTS_LITTLE_ENDIAN
- select SYS_SUPPORTS_BIG_ENDIAN
-@@ -346,6 +347,7 @@ config MACH_JAZZ
- select CSRC_R4K
- select DEFAULT_SGI_PARTITION if CPU_BIG_ENDIAN
- select GENERIC_ISA_DMA
-+ select DMA_UNMAP_POST_FLUSH
- select HAVE_PCSPKR_PLATFORM
- select IRQ_MIPS_CPU
- select I8253
-@@ -1128,6 +1130,9 @@ config DMA_NONCOHERENT
+@@ -1116,7 +1116,6 @@ config DMA_PERDEV_COHERENT
+ config DMA_NONCOHERENT
bool
+ select ARCH_HAS_SYNC_DMA_FOR_DEVICE
+- select ARCH_HAS_SYNC_DMA_FOR_CPU
select NEED_DMA_MAP_STATE
-
-+config DMA_UNMAP_POST_FLUSH
-+ bool
-+
- config NEED_DMA_MAP_STATE
- bool
-
-@@ -1652,6 +1657,7 @@ config CPU_R10000
- select CPU_SUPPORTS_64BIT_KERNEL
- select CPU_SUPPORTS_HIGHMEM
- select CPU_SUPPORTS_HUGEPAGES
-+ select DMA_UNMAP_POST_FLUSH
- help
- MIPS Technologies R10000-series processors.
-
-@@ -1900,9 +1906,11 @@ config SYS_HAS_CPU_MIPS32_R3_5
- bool
+ select DMA_NONCOHERENT_MMAP
+ select DMA_NONCOHERENT_CACHE_SYNC
+@@ -1897,9 +1896,11 @@ config SYS_HAS_CPU_MIPS32_R3_5
config SYS_HAS_CPU_MIPS32_R5
-+ select DMA_UNMAP_POST_FLUSH
bool
++ select ARCH_HAS_SYNC_DMA_FOR_CPU
config SYS_HAS_CPU_MIPS32_R6
-+ select DMA_UNMAP_POST_FLUSH
bool
++ select ARCH_HAS_SYNC_DMA_FOR_CPU
config SYS_HAS_CPU_MIPS64_R1
-@@ -1912,6 +1920,7 @@ config SYS_HAS_CPU_MIPS64_R2
bool
+@@ -1909,6 +1910,7 @@ config SYS_HAS_CPU_MIPS64_R2
config SYS_HAS_CPU_MIPS64_R6
-+ select DMA_UNMAP_POST_FLUSH
bool
++ select ARCH_HAS_SYNC_DMA_FOR_CPU
config SYS_HAS_CPU_R3000
---- a/arch/mips/mm/dma-default.c
-+++ b/arch/mips/mm/dma-default.c
-@@ -267,8 +267,9 @@ static inline void __dma_sync(struct pag
- } while (left);
- }
+ bool
+@@ -1945,6 +1947,7 @@ config SYS_HAS_CPU_R8000
--static void mips_dma_unmap_page(struct device *dev, dma_addr_t dma_addr,
-- size_t size, enum dma_data_direction direction, unsigned long attrs)
-+static void __maybe_unused
-+mips_dma_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
-+ enum dma_data_direction direction, unsigned long attrs)
- {
- if (cpu_needs_post_dma_flush(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
- __dma_sync(dma_addr_to_page(dev, dma_addr),
-@@ -308,9 +309,10 @@ static dma_addr_t mips_dma_map_page(stru
- return plat_map_dma_mem_page(dev, page) + offset;
- }
+ config SYS_HAS_CPU_R10000
+ bool
++ select ARCH_HAS_SYNC_DMA_FOR_CPU
--static void mips_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
-- int nhwentries, enum dma_data_direction direction,
-- unsigned long attrs)
-+static void __maybe_unused
-+mips_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
-+ int nhwentries, enum dma_data_direction direction,
-+ unsigned long attrs)
- {
- int i;
- struct scatterlist *sg;
-@@ -325,8 +327,9 @@ static void mips_dma_unmap_sg(struct dev
- }
+ config SYS_HAS_CPU_RM7000
+ bool
+@@ -1973,6 +1976,7 @@ config SYS_HAS_CPU_BMIPS4380
+ config SYS_HAS_CPU_BMIPS5000
+ bool
+ select SYS_HAS_CPU_BMIPS
++ select ARCH_HAS_SYNC_DMA_FOR_CPU
+
+ config SYS_HAS_CPU_XLR
+ bool
+--- a/arch/mips/mm/dma-noncoherent.c
++++ b/arch/mips/mm/dma-noncoherent.c
+@@ -191,12 +191,14 @@ void arch_sync_dma_for_device(struct dev
+ dma_sync_phys(paddr, size, dir);
}
--static void mips_dma_sync_single_for_cpu(struct device *dev,
-- dma_addr_t dma_handle, size_t size, enum dma_data_direction direction)
-+static void __maybe_unused
-+mips_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
-+ size_t size, enum dma_data_direction direction)
++#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU
+ void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
+ size_t size, enum dma_data_direction dir)
{
if (cpu_needs_post_dma_flush(dev))
- __dma_sync(dma_addr_to_page(dev, dma_handle),
-@@ -342,9 +345,9 @@ static void mips_dma_sync_single_for_dev
- dma_handle & ~PAGE_MASK, size, direction);
+ dma_sync_phys(paddr, size, dir);
}
-
--static void mips_dma_sync_sg_for_cpu(struct device *dev,
-- struct scatterlist *sglist, int nelems,
-- enum dma_data_direction direction)
-+static void __maybe_unused
-+mips_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist,
-+ int nelems, enum dma_data_direction direction)
- {
- int i;
- struct scatterlist *sg;
-@@ -394,12 +397,14 @@ static const struct dma_map_ops mips_def
- .free = mips_dma_free_coherent,
- .mmap = mips_dma_mmap,
- .map_page = mips_dma_map_page,
-- .unmap_page = mips_dma_unmap_page,
- .map_sg = mips_dma_map_sg,
-+#ifdef CONFIG_DMA_UNMAP_POST_FLUSH
-+ .unmap_page = mips_dma_unmap_page,
- .unmap_sg = mips_dma_unmap_sg,
- .sync_single_for_cpu = mips_dma_sync_single_for_cpu,
-- .sync_single_for_device = mips_dma_sync_single_for_device,
- .sync_sg_for_cpu = mips_dma_sync_sg_for_cpu,
+#endif
-+ .sync_single_for_device = mips_dma_sync_single_for_device,
- .sync_sg_for_device = mips_dma_sync_sg_for_device,
- .dma_supported = mips_dma_supported
- };
+
+ void arch_dma_cache_sync(struct device *dev, void *vaddr, size_t size,
+ enum dma_data_direction direction)