[PATCH 07/22] arm-nommu: use generic dma_noncoherent_ops

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

Switch to the generic noncoherent direct mapping implementation for
the nommu dma map implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/arc/Kconfig | 1 +
arch/arm/Kconfig | 4 +
arch/arm/mm/dma-mapping-nommu.c | 139 +++++---------------------------
3 files changed, 23 insertions(+), 121 deletions(-)

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 89d47eac18b2..3a492a9aeaad 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -9,6 +9,7 @@
config ARC
def_bool y
select ARC_TIMERS
+ select ARCH_HAS_SYNC_DMA_FOR_DEVICE
select ARCH_HAS_SYNC_DMA_FOR_CPU
select ARCH_HAS_SYNC_DMA_FOR_DEVICE
select ARCH_HAS_SG_CHAIN
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index f91f69174630..eacc45ac4e77 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -12,6 +12,8 @@ config ARM
select ARCH_HAS_PHYS_TO_DMA
select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
select ARCH_HAS_STRICT_MODULE_RWX if MMU
+ select ARCH_HAS_SYNC_DMA_FOR_CPU if !MMU
+ select ARCH_HAS_SYNC_DMA_FOR_DEVICE if !MMU
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAVE_CUSTOM_GPIO_H
select ARCH_HAS_GCOV_PROFILE_ALL
@@ -27,6 +29,8 @@ config ARM
select CPU_PM if (SUSPEND || CPU_IDLE)
select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
select DMA_DIRECT_OPS if !MMU
+ select DMA_NONCOHERENT_OPS if !MMU
+ select DMA_NONCOHERENT_MMAP if !MMU
select EDAC_SUPPORT
select EDAC_ATOMIC_SCRUB
select GENERIC_ALLOCATOR
diff --git a/arch/arm/mm/dma-mapping-nommu.c b/arch/arm/mm/dma-mapping-nommu.c
index f448a0663b10..a74ed6632982 100644
--- a/arch/arm/mm/dma-mapping-nommu.c
+++ b/arch/arm/mm/dma-mapping-nommu.c
@@ -12,6 +12,7 @@
#include <linux/export.h>
#include <linux/mm.h>
#include <linux/dma-direct.h>
+#include <linux/dma-noncoherent.h>
#include <linux/scatterlist.h>

#include <asm/cachetype.h>
@@ -26,18 +27,16 @@
* - MMU/MPU is off
* - cpu is v7m w/o cache support
* - device is coherent
- * otherwise arm_nommu_dma_ops is used.
+ * otherwise dma_noncoherent_ops is used.
*
- * arm_nommu_dma_ops rely on consistent DMA memory (please, refer to
+ * dma_noncoherent_ops rely on consistent DMA memory (please, refer to
* [1] on how to declare such memory).
*
* [1] Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
*/

-static void *arm_nommu_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)
{
void *ret;

@@ -65,9 +64,8 @@ static void *arm_nommu_dma_alloc(struct device *dev, size_t size,
return ret;
}

-static void arm_nommu_dma_free(struct device *dev, size_t size,
- void *cpu_addr, dma_addr_t dma_addr,
- unsigned long attrs)
+void arch_dma_free(struct device *dev, size_t size, void *cpu_addr,
+ dma_addr_t dma_addr, unsigned long attrs)
{
if (attrs & DMA_ATTR_NON_CONSISTENT) {
dma_direct_free(dev, size, cpu_addr, dma_addr, attrs);
@@ -81,9 +79,9 @@ static void arm_nommu_dma_free(struct device *dev, size_t size,
return;
}

-static int arm_nommu_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)
{
int ret;

@@ -93,9 +91,8 @@ static int arm_nommu_dma_mmap(struct device *dev, struct vm_area_struct *vma,
return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
}

-
-static void __dma_page_cpu_to_dev(phys_addr_t paddr, 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)
{
dmac_map_area(__va(paddr), size, dir);

@@ -105,8 +102,8 @@ static void __dma_page_cpu_to_dev(phys_addr_t paddr, size_t size,
outer_clean_range(paddr, paddr + size);
}

-static void __dma_page_dev_to_cpu(phys_addr_t paddr, size_t size,
- 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)
{
if (dir != DMA_TO_DEVICE) {
outer_inv_range(paddr, paddr + size);
@@ -114,110 +111,9 @@ static void __dma_page_dev_to_cpu(phys_addr_t paddr, size_t size,
}
}

-static dma_addr_t arm_nommu_dma_map_page(struct device *dev, struct page *page,
- unsigned long offset, size_t size,
- enum dma_data_direction dir,
- unsigned long attrs)
-{
- dma_addr_t handle = page_to_phys(page) + offset;
-
- __dma_page_cpu_to_dev(handle, size, dir);
-
- return handle;
-}
-
-static void arm_nommu_dma_unmap_page(struct device *dev, dma_addr_t handle,
- size_t size, enum dma_data_direction dir,
- unsigned long attrs)
-{
- __dma_page_dev_to_cpu(handle, size, dir);
-}
-
-
-static int arm_nommu_dma_map_sg(struct device *dev, struct scatterlist *sgl,
- int nents, enum dma_data_direction dir,
- unsigned long attrs)
-{
- int i;
- struct scatterlist *sg;
-
- for_each_sg(sgl, sg, nents, i) {
- sg_dma_address(sg) = sg_phys(sg);
- sg_dma_len(sg) = sg->length;
- __dma_page_cpu_to_dev(sg_dma_address(sg), sg_dma_len(sg), dir);
- }
-
- return nents;
-}
-
-static void arm_nommu_dma_unmap_sg(struct device *dev, struct scatterlist *sgl,
- int nents, enum dma_data_direction dir,
- unsigned long attrs)
-{
- struct scatterlist *sg;
- int i;
-
- for_each_sg(sgl, sg, nents, i)
- __dma_page_dev_to_cpu(sg_dma_address(sg), sg_dma_len(sg), dir);
-}
-
-static void arm_nommu_dma_sync_single_for_device(struct device *dev,
- dma_addr_t handle, size_t size, enum dma_data_direction dir)
-{
- __dma_page_cpu_to_dev(handle, size, dir);
-}
-
-static void arm_nommu_dma_sync_single_for_cpu(struct device *dev,
- dma_addr_t handle, size_t size, enum dma_data_direction dir)
-{
- __dma_page_cpu_to_dev(handle, size, dir);
-}
-
-static void arm_nommu_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sgl,
- int nents, enum dma_data_direction dir)
-{
- struct scatterlist *sg;
- int i;
-
- for_each_sg(sgl, sg, nents, i)
- __dma_page_cpu_to_dev(sg_dma_address(sg), sg_dma_len(sg), dir);
-}
-
-static void arm_nommu_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sgl,
- int nents, enum dma_data_direction dir)
-{
- struct scatterlist *sg;
- int i;
-
- for_each_sg(sgl, sg, nents, i)
- __dma_page_dev_to_cpu(sg_dma_address(sg), sg_dma_len(sg), dir);
-}
-
-const struct dma_map_ops arm_nommu_dma_ops = {
- .alloc = arm_nommu_dma_alloc,
- .free = arm_nommu_dma_free,
- .mmap = arm_nommu_dma_mmap,
- .map_page = arm_nommu_dma_map_page,
- .unmap_page = arm_nommu_dma_unmap_page,
- .map_sg = arm_nommu_dma_map_sg,
- .unmap_sg = arm_nommu_dma_unmap_sg,
- .sync_single_for_device = arm_nommu_dma_sync_single_for_device,
- .sync_single_for_cpu = arm_nommu_dma_sync_single_for_cpu,
- .sync_sg_for_device = arm_nommu_dma_sync_sg_for_device,
- .sync_sg_for_cpu = arm_nommu_dma_sync_sg_for_cpu,
-};
-EXPORT_SYMBOL(arm_nommu_dma_ops);
-
-static const struct dma_map_ops *arm_nommu_get_dma_map_ops(bool coherent)
-{
- return coherent ? &dma_direct_ops : &arm_nommu_dma_ops;
-}
-
void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
const struct iommu_ops *iommu, bool coherent)
{
- const struct dma_map_ops *dma_ops;
-
if (IS_ENABLED(CONFIG_CPU_V7M)) {
/*
* Cache support for v7m is optional, so can be treated as
@@ -233,9 +129,10 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
dev->archdata.dma_coherent = (get_cr() & CR_M) ? coherent : true;
}

- dma_ops = arm_nommu_get_dma_map_ops(dev->archdata.dma_coherent);
-
- set_dma_ops(dev, dma_ops);
+ if (dev->archdata.dma_coherent)
+ set_dma_ops(dev, &dma_direct_ops);
+ else
+ set_dma_ops(dev, &dma_noncoherent_ops);
}

void arch_teardown_dma_ops(struct device *dev)
--
2.17.0