[PATCH 06/22] arc: use generic dma_noncoherent_ops

Christoph Hellwig
2018-04-20T08:04:17Z

Switch to the generic noncoherent direct mapping implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/arc/Kconfig | 4 +
arch/arc/include/asm/Kbuild | 1 +
arch/arc/include/asm/dma-mapping.h | 21 -----
arch/arc/mm/dma.c | 141 +++--------------------------
4 files changed, 19 insertions(+), 148 deletions(-)
delete mode 100644 arch/arc/include/asm/dma-mapping.h

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 7498aca4b887..89d47eac18b2 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -9,11 +9,15 @@
config ARC
def_bool y
select ARC_TIMERS
+ select ARCH_HAS_SYNC_DMA_FOR_CPU
+ select ARCH_HAS_SYNC_DMA_FOR_DEVICE
select ARCH_HAS_SG_CHAIN
select ARCH_SUPPORTS_ATOMIC_RMW if ARC_HAS_LLSC
select BUILDTIME_EXTABLE_SORT
select CLONE_BACKWARDS
select COMMON_CLK
+ select DMA_NONCOHERENT_OPS
+ select DMA_NONCOHERENT_MMAP
select GENERIC_ATOMIC64 if !ISA_ARCV2 || !(ARC_HAS_LL64 && ARC_HAS_LLSC)
select GENERIC_CLOCKEVENTS
select GENERIC_FIND_FIRST_BIT
diff --git a/arch/arc/include/asm/Kbuild b/arch/arc/include/asm/Kbuild
index 4bd5d4369e05..bbdcb955e18f 100644
--- a/arch/arc/include/asm/Kbuild
+++ b/arch/arc/include/asm/Kbuild
@@ -2,6 +2,7 @@
generic-y += bugs.h
generic-y += device.h
generic-y += div64.h
+generic-y += dma-mapping.h
generic-y += emergency-restart.h
generic-y += extable.h
generic-y += fb.h
diff --git a/arch/arc/include/asm/dma-mapping.h b/arch/arc/include/asm/dma-mapping.h
deleted file mode 100644
index 7a16824bfe98..000000000000
--- a/arch/arc/include/asm/dma-mapping.h
+++ /dev/null
@@ -1,21 +0,0 @@
-/*
- * DMA Mapping glue for ARC
- *
- * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#ifndef ASM_ARC_DMA_MAPPING_H
-#define ASM_ARC_DMA_MAPPING_H
-
-extern const struct dma_map_ops arc_dma_ops;
-
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
-{
- return &arc_dma_ops;
-}
-
-#endif
diff --git a/arch/arc/mm/dma.c b/arch/arc/mm/dma.c
index 1dcc404b5aec..ecfeb5585cc7 100644
--- a/arch/arc/mm/dma.c
+++ b/arch/arc/mm/dma.c
@@ -16,13 +16,12 @@
* The default DMA address == Phy address which is 0x8000_0000 based.
*/

-#include <linux/dma-mapping.h>
+#include <linux/dma-noncoherent.h>
#include <asm/cache.h>
#include <asm/cacheflush.h>

-
-static void *arc_dma_alloc(struct device *dev, size_t size,
- dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
+void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
+ gfp_t gfp, unsigned long attrs)
{
unsigned long order = get_order(size);
struct page *page;
@@ -89,7 +88,7 @@ static void *arc_dma_alloc(struct device *dev, size_t size,
return kvaddr;
}

-static void arc_dma_free(struct device *dev, size_t size, void *vaddr,
+void arch_dma_free(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle, unsigned long attrs)
{
phys_addr_t paddr = dma_handle;
@@ -105,9 +104,9 @@ static void arc_dma_free(struct device *dev, size_t size, void *vaddr,
__free_pages(page, get_order(size));
}

-static int arc_dma_mmap(struct device *dev, struct vm_area_struct *vma,
- void *cpu_addr, dma_addr_t dma_addr, size_t size,
- unsigned long attrs)
+int arch_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
+ unsigned long attrs)
{
unsigned long user_count = vma_pages(vma);
unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
@@ -135,7 +134,7 @@ static int arc_dma_mmap(struct device *dev, struct vm_area_struct *vma,
* CPU accesses page via normal paddr, thus needs to explicitly made
* consistent before each use
*/
-static void _dma_cache_sync(phys_addr_t paddr, size_t size,
+static void _dma_cache_sync(struct device *dev, phys_addr_t paddr size_t size,
enum dma_data_direction dir)
{
switch (dir) {
@@ -153,126 +152,14 @@ static void _dma_cache_sync(phys_addr_t paddr, size_t size,
}
}

-/*
- * arc_dma_map_page - map a portion of a page for streaming DMA
- *
- * Ensure that any data held in the cache is appropriately discarded
- * or written back.
- *
- * The device owns this memory once this call has completed. The CPU
- * can regain ownership by calling dma_unmap_page().
- *
- * Note: while it takes struct page as arg, caller can "abuse" it to pass
- * a region larger than PAGE_SIZE, provided it is physically contiguous
- * and this still works correctly
- */
-static dma_addr_t arc_dma_map_page(struct device *dev, struct page *page,
- unsigned long offset, size_t size, enum dma_data_direction dir,
- unsigned long attrs)
-{
- phys_addr_t paddr = page_to_phys(page) + offset;
-
- if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
- _dma_cache_sync(paddr, size, dir);
-
- return paddr;
-}
-
-/*
- * arc_dma_unmap_page - unmap a buffer previously mapped through dma_map_page()
- *
- * After this call, reads by the CPU to the buffer are guaranteed to see
- * whatever the device wrote there.
- *
- * Note: historically this routine was not implemented for ARC
- */
-static void arc_dma_unmap_page(struct device *dev, dma_addr_t handle,
- size_t size, enum dma_data_direction dir,
- unsigned long attrs)
-{
- phys_addr_t paddr = handle;
-
- if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
- _dma_cache_sync(paddr, size, dir);
-}
-
-static int arc_dma_map_sg(struct device *dev, struct scatterlist *sg,
- int nents, enum dma_data_direction dir, unsigned long attrs)
-{
- struct scatterlist *s;
- int i;
-
- for_each_sg(sg, s, nents, i)
- s->dma_address = dma_map_page(dev, sg_page(s), s->offset,
- s->length, dir);
-
- return nents;
-}
-
-static void arc_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
- int nents, enum dma_data_direction dir,
- unsigned long attrs)
-{
- struct scatterlist *s;
- int i;
-
- for_each_sg(sg, s, nents, i)
- arc_dma_unmap_page(dev, sg_dma_address(s), sg_dma_len(s), dir,
- attrs);
-}
-
-static void arc_dma_sync_single_for_cpu(struct device *dev,
- dma_addr_t dma_handle, size_t size, enum dma_data_direction dir)
-{
- _dma_cache_sync(dma_handle, size, DMA_FROM_DEVICE);
-}
-
-static void arc_dma_sync_single_for_device(struct device *dev,
- dma_addr_t dma_handle, size_t size, enum dma_data_direction dir)
+void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
+ size_t size, enum dma_data_direction dir)
{
- _dma_cache_sync(dma_handle, size, DMA_TO_DEVICE);
+ return _dma_cache_sync(dev, paddr, size, dir);
}

-static void arc_dma_sync_sg_for_cpu(struct device *dev,
- struct scatterlist *sglist, int nelems,
- enum dma_data_direction dir)
+void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
+ size_t size, enum dma_data_direction dir)
{
- int i;
- struct scatterlist *sg;
-
- for_each_sg(sglist, sg, nelems, i)
- _dma_cache_sync(sg_phys(sg), sg->length, dir);
+ return _dma_cache_sync(dev, paddr, size, dir);
}
-
-static void arc_dma_sync_sg_for_device(struct device *dev,
- struct scatterlist *sglist, int nelems,
- enum dma_data_direction dir)
-{
- int i;
- struct scatterlist *sg;
-
- for_each_sg(sglist, sg, nelems, i)
- _dma_cache_sync(sg_phys(sg), sg->length, dir);
-}
-
-static int arc_dma_supported(struct device *dev, u64 dma_mask)
-{
- /* Support 32 bit DMA mask exclusively */
- return dma_mask == DMA_BIT_MASK(32);
-}
-
-const struct dma_map_ops arc_dma_ops = {
- .alloc = arc_dma_alloc,
- .free = arc_dma_free,
- .mmap = arc_dma_mmap,
- .map_page = arc_dma_map_page,
- .unmap_page = arc_dma_unmap_page,
- .map_sg = arc_dma_map_sg,
- .unmap_sg = arc_dma_unmap_sg,
- .sync_single_for_device = arc_dma_sync_single_for_device,
- .sync_single_for_cpu = arc_dma_sync_single_for_cpu,
- .sync_sg_for_cpu = arc_dma_sync_sg_for_cpu,
- .sync_sg_for_device = arc_dma_sync_sg_for_device,
- .dma_supported = arc_dma_supported,
-};
-EXPORT_SYMBOL(arc_dma_ops);
--
2.17.0