[PATCH 22/22] parisc: use generic dma_noncoherent_ops

Christoph Hellwig
2018-04-20T08:05:24Z

Switch to the generic noncoherent direct mapping implementation.

Parisc previously had two different non-coherent dma ops implementation
that just different in the way coherent allocations were handled or not
handled. The different behavior is not selected at runtime in the
arch_dma_alloc and arch_dma_free routines. The non-coherent allocation
in the pcx cases now uses the dma_direct helpers that are a little more
sophisticated and used by a lot of other architectures.

Fix sync_single_for_cpu to do skip the cache flush unless the transfer
is to the device to match the more tested unmap_single path which should
have the same cache coherency implications.

This also now consistenly uses flush_kernel_dcache_range for cache
flushing while previously some of the SG based operations used
flush_kernel_vmap_range instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/parisc/Kconfig | 4 +
arch/parisc/include/asm/dma-mapping.h | 5 -
arch/parisc/kernel/pci-dma.c | 181 ++++----------------------
arch/parisc/kernel/setup.c | 8 +-
arch/parisc/mm/init.c | 11 +-
5 files changed, 35 insertions(+), 174 deletions(-)

diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index 47047f0cbe35..80166a1cbcb7 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -188,6 +188,10 @@ config PA20
config PA11
def_bool y
depends on PA7000 || PA7100LC || PA7200 || PA7300LC
+ select ARCH_HAS_SYNC_DMA_FOR_CPU
+ select ARCH_HAS_SYNC_DMA_FOR_DEVICE
+ select DMA_NONCOHERENT_OPS
+ select DMA_NONCOHERENT_CACHE_SYNC

config PREFETCH
def_bool y
diff --git a/arch/parisc/include/asm/dma-mapping.h b/arch/parisc/include/asm/dma-mapping.h
index 01e1fc057c83..44a9f97194aa 100644
--- a/arch/parisc/include/asm/dma-mapping.h
+++ b/arch/parisc/include/asm/dma-mapping.h
@@ -21,11 +21,6 @@
** flush/purge and allocate "regular" cacheable pages for everything.
*/

-#ifdef CONFIG_PA11
-extern const struct dma_map_ops pcxl_dma_ops;
-extern const struct dma_map_ops pcx_dma_ops;
-#endif
-
extern const struct dma_map_ops *hppa_dma_ops;

static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c
index 91bc0cac03a1..235e2e53959e 100644
--- a/arch/parisc/kernel/pci-dma.c
+++ b/arch/parisc/kernel/pci-dma.c
@@ -21,13 +21,12 @@
#include <linux/init.h>
#include <linux/gfp.h>
#include <linux/mm.h>
-#include <linux/pci.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/string.h>
#include <linux/types.h>
-#include <linux/scatterlist.h>
-#include <linux/export.h>
+#include <linux/dma-direct.h>
+#include <linux/dma-noncoherent.h>

#include <asm/cacheflush.h>
#include <asm/dma.h> /* for DMA_CHUNK_SIZE */
@@ -447,178 +446,48 @@ static void pa11_dma_free(struct device *dev, size_t size, void *vaddr,
free_pages((unsigned long)__va(dma_handle), order);
}

-static dma_addr_t pa11_dma_map_page(struct device *dev, struct page *page,
- unsigned long offset, size_t size,
- enum dma_data_direction direction, unsigned long attrs)
+void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
+ size_t size, enum dma_data_direction dir)
{
- void *addr = page_address(page) + offset;
- BUG_ON(direction == DMA_NONE);
-
- if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
- flush_kernel_dcache_range((unsigned long) addr, size);
-
- return virt_to_phys(addr);
+ flush_kernel_dcache_range((unsigned long)phys_to_virt(paddr), size);
}

-static void pa11_dma_unmap_page(struct device *dev, dma_addr_t dma_handle,
- size_t size, enum dma_data_direction direction,
- unsigned long attrs)
+void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
+ size_t size, enum dma_data_direction dir)
{
- BUG_ON(direction == DMA_NONE);
-
- if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
- return;
-
- if (direction == DMA_TO_DEVICE)
+ if (dir == DMA_TO_DEVICE)
return;

/*
- * For PCI_DMA_FROMDEVICE this flush is not necessary for the
+ * For DMA_FROM_DEVICE this flush is not necessary for the
* simple map/unmap case. However, it IS necessary if if
- * pci_dma_sync_single_* has been called and the buffer reused.
+ * dma_sync_single_* has been called and the buffer reused.
*/

- flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
-}
-
-static int pa11_dma_map_sg(struct device *dev, struct scatterlist *sglist,
- int nents, enum dma_data_direction direction,
- unsigned long attrs)
-{
- int i;
- struct scatterlist *sg;
-
- BUG_ON(direction == DMA_NONE);
-
- for_each_sg(sglist, sg, nents, i) {
- unsigned long vaddr = (unsigned long)sg_virt(sg);
-
- sg_dma_address(sg) = (dma_addr_t) virt_to_phys(vaddr);
- sg_dma_len(sg) = sg->length;
-
- if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
- continue;
-
- flush_kernel_dcache_range(vaddr, sg->length);
- }
- return nents;
+ flush_kernel_dcache_range((unsigned long)phys_to_virt(paddr), size);
}

-static void pa11_dma_unmap_sg(struct device *dev, struct scatterlist *sglist,
- int nents, enum dma_data_direction direction,
- unsigned long attrs)
-{
- int i;
- struct scatterlist *sg;
-
- BUG_ON(direction == DMA_NONE);
-
- if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
- return;
-
- if (direction == DMA_TO_DEVICE)
- return;
-
- /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
-
- for_each_sg(sglist, sg, nents, i)
- flush_kernel_vmap_range(sg_virt(sg), sg->length);
-}
-
-static void pa11_dma_sync_single_for_cpu(struct device *dev,
- dma_addr_t dma_handle, size_t size,
- enum dma_data_direction direction)
-{
- BUG_ON(direction == DMA_NONE);
-
- flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle),
- size);
-}
-
-static void pa11_dma_sync_single_for_device(struct device *dev,
- dma_addr_t dma_handle, size_t size,
- enum dma_data_direction direction)
-{
- BUG_ON(direction == DMA_NONE);
-
- flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle),
- size);
-}
-
-static void pa11_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
-{
- int i;
- struct scatterlist *sg;
-
- /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
-
- for_each_sg(sglist, sg, nents, i)
- flush_kernel_vmap_range(sg_virt(sg), sg->length);
-}
-
-static void pa11_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist, int nents, enum dma_data_direction direction)
-{
- int i;
- struct scatterlist *sg;
-
- /* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
-
- for_each_sg(sglist, sg, nents, i)
- flush_kernel_vmap_range(sg_virt(sg), sg->length);
-}
-
-static void pa11_dma_cache_sync(struct device *dev, void *vaddr, size_t size,
+void arch_dma_cache_sync(struct device *dev, void *vaddr, size_t size,
enum dma_data_direction direction)
{
flush_kernel_dcache_range((unsigned long)vaddr, size);
}

-const struct dma_map_ops pcxl_dma_ops = {
- .alloc = pa11_dma_alloc,
- .free = pa11_dma_free,
- .map_page = pa11_dma_map_page,
- .unmap_page = pa11_dma_unmap_page,
- .map_sg = pa11_dma_map_sg,
- .unmap_sg = pa11_dma_unmap_sg,
- .sync_single_for_cpu = pa11_dma_sync_single_for_cpu,
- .sync_single_for_device = pa11_dma_sync_single_for_device,
- .sync_sg_for_cpu = pa11_dma_sync_sg_for_cpu,
- .sync_sg_for_device = pa11_dma_sync_sg_for_device,
- .cache_sync = pa11_dma_cache_sync,
-};
-
-static void *pcx_dma_alloc(struct device *dev, size_t size,
- dma_addr_t *dma_handle, gfp_t flag, 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 *addr;
-
- if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0)
- return NULL;
-
- addr = (void *)__get_free_pages(flag, get_order(size));
- if (addr)
- *dma_handle = (dma_addr_t)virt_to_phys(addr);
-
- return addr;
+ if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl)
+ return pa11_dma_alloc(dev, size, dma_handle, gfp, attrs);
+ if (attrs & DMA_ATTR_NON_CONSISTENT)
+ return dma_direct_alloc(dev, size, dma_handle, gfp, attrs);
+ return NULL;
}

-static void pcx_dma_free(struct device *dev, size_t size, void *vaddr,
- dma_addr_t iova, unsigned long attrs)
+void arch_dma_free(struct device *dev, size_t size, void *cpu_addr,
+ dma_addr_t dma_addr, unsigned long attrs)
{
- free_pages((unsigned long)vaddr, get_order(size));
- return;
+ if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl)
+ pa11_dma_free(dev, size, cpu_addr, dma_addr, attrs);
+ else
+ dma_direct_free(dev, size, cpu_addr, dma_addr, attrs);
}
-
-const struct dma_map_ops pcx_dma_ops = {
- .alloc = pcx_dma_alloc,
- .free = pcx_dma_free,
- .map_page = pa11_dma_map_page,
- .unmap_page = pa11_dma_unmap_page,
- .map_sg = pa11_dma_map_sg,
- .unmap_sg = pa11_dma_unmap_sg,
- .sync_single_for_cpu = pa11_dma_sync_single_for_cpu,
- .sync_single_for_device = pa11_dma_sync_single_for_device,
- .sync_sg_for_cpu = pa11_dma_sync_sg_for_cpu,
- .sync_sg_for_device = pa11_dma_sync_sg_for_device,
- .cache_sync = pa11_dma_cache_sync,
-};
diff --git a/arch/parisc/kernel/setup.c b/arch/parisc/kernel/setup.c
index 8d3a7b80ac42..4e87c35c22b7 100644
--- a/arch/parisc/kernel/setup.c
+++ b/arch/parisc/kernel/setup.c
@@ -97,14 +97,12 @@ void __init dma_ops_init(void)
panic( "PA-RISC Linux currently only supports machines that conform to\n"
"the PA-RISC 1.1 or 2.0 architecture specification.\n");

- case pcxs:
- case pcxt:
- hppa_dma_ops = &pcx_dma_ops;
- break;
case pcxl2:
pa7300lc_init();
case pcxl: /* falls through */
- hppa_dma_ops = &pcxl_dma_ops;
+ case pcxs:
+ case pcxt:
+ hppa_dma_ops = &dma_noncoherent_ops;
break;
default:
break;
diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index cab32ee824d2..4ad91c28ecbe 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -19,7 +19,6 @@
#include <linux/gfp.h>
#include <linux/delay.h>
#include <linux/init.h>
-#include <linux/pci.h> /* for hppa_dma_ops and pcxl_dma_ops */
#include <linux/initrd.h>
#include <linux/swap.h>
#include <linux/unistd.h>
@@ -616,17 +615,13 @@ void __init mem_init(void)
free_all_bootmem();

#ifdef CONFIG_PA11
- if (hppa_dma_ops == &pcxl_dma_ops) {
+ if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) {
pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start
+ PCXL_DMA_MAP_SIZE);
- } else {
- pcxl_dma_start = 0;
- parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START);
- }
-#else
- parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START);
+ } else
#endif
+ parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START);

mem_init_print_info(NULL);

--
2.17.0