xtensa: enable HAVE_DMA_CONTIGUOUS
Enable HAVE_DMA_CONTIGUOUS, reserve contiguous memory at bootmem_init,
use dma_alloc_from_contiguous and dma_release_from_contiguous in
xtensa_dma_alloc/free.
This allows for big contiguous DMA buffer allocation from designated
area configured in the device tree.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index f610586..f4126cf 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -15,6 +15,7 @@
select GENERIC_SCHED_CLOCK
select HAVE_DEBUG_KMEMLEAK
select HAVE_DMA_API_DEBUG
+ select HAVE_DMA_CONTIGUOUS
select HAVE_EXIT_THREAD
select HAVE_FUNCTION_TRACER
select HAVE_FUTEX_CMPXCHG if !MMU
diff --git a/arch/xtensa/include/asm/Kbuild b/arch/xtensa/include/asm/Kbuild
index 28cf4c5..b7fbaa5 100644
--- a/arch/xtensa/include/asm/Kbuild
+++ b/arch/xtensa/include/asm/Kbuild
@@ -3,6 +3,7 @@
generic-y += clkdev.h
generic-y += cputime.h
generic-y += div64.h
+generic-y += dma-contiguous.h
generic-y += emergency-restart.h
generic-y += errno.h
generic-y += exec.h
diff --git a/arch/xtensa/kernel/pci-dma.c b/arch/xtensa/kernel/pci-dma.c
index 1e68806..10e5b8a 100644
--- a/arch/xtensa/kernel/pci-dma.c
+++ b/arch/xtensa/kernel/pci-dma.c
@@ -15,6 +15,7 @@
* Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
*/
+#include <linux/dma-contiguous.h>
#include <linux/gfp.h>
#include <linux/highmem.h>
#include <linux/mm.h>
@@ -146,6 +147,8 @@
{
unsigned long ret;
unsigned long uncached = 0;
+ unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ struct page *page = NULL;
/* ignore region speicifiers */
@@ -153,11 +156,18 @@
if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
flag |= GFP_DMA;
- ret = (unsigned long)__get_free_pages(flag, get_order(size));
- if (ret == 0)
+ if (gfpflags_allow_blocking(flag))
+ page = dma_alloc_from_contiguous(dev, count, get_order(size));
+
+ if (!page)
+ page = alloc_pages(flag, get_order(size));
+
+ if (!page)
return NULL;
+ ret = (unsigned long)page_address(page);
+
/* We currently don't support coherent memory outside KSEG */
BUG_ON(ret < XCHAL_KSEG_CACHED_VADDR ||
@@ -170,16 +180,19 @@
return (void *)uncached;
}
-static void xtensa_dma_free(struct device *hwdev, size_t size, void *vaddr,
+static void xtensa_dma_free(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle, unsigned long attrs)
{
unsigned long addr = (unsigned long)vaddr +
XCHAL_KSEG_CACHED_VADDR - XCHAL_KSEG_BYPASS_VADDR;
+ struct page *page = virt_to_page(addr);
+ unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
BUG_ON(addr < XCHAL_KSEG_CACHED_VADDR ||
addr > XCHAL_KSEG_CACHED_VADDR + XCHAL_KSEG_SIZE - 1);
- free_pages(addr, get_order(size));
+ if (!dma_release_from_contiguous(dev, page, count))
+ __free_pages(page, get_order(size));
}
static dma_addr_t xtensa_map_page(struct device *dev, struct page *page,
diff --git a/arch/xtensa/mm/init.c b/arch/xtensa/mm/init.c
index 80e4cfb..720fe4e 100644
--- a/arch/xtensa/mm/init.c
+++ b/arch/xtensa/mm/init.c
@@ -26,6 +26,7 @@
#include <linux/nodemask.h>
#include <linux/mm.h>
#include <linux/of_fdt.h>
+#include <linux/dma-contiguous.h>
#include <asm/bootparam.h>
#include <asm/page.h>
@@ -60,6 +61,7 @@
max_low_pfn = min(max_pfn, MAX_LOW_PFN);
memblock_set_current_limit(PFN_PHYS(max_low_pfn));
+ dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
memblock_dump_all();
}