aboutsummaryrefslogtreecommitdiffstats
path: root/mm
diff options
context:
space:
mode:
authorMarek Szyprowski <m.szyprowski@samsung.com>2014-10-13 15:51:09 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-10-14 02:18:12 +0200
commitde9e14eebf33a60712a52a0bc6e08c043c0aba53 (patch)
tree7b681bf9d5cb6a7909c8d9090aaa868d3e22ccf2 /mm
parent7bfa5ab6fa1b18f53fb94f922e107e6fbdc5e485 (diff)
drivers: dma-contiguous: add initialization from device tree
Add a function to create CMA region from previously reserved memory and add support for handling 'shared-dma-pool' reserved-memory device tree nodes. Based on previous code provided by Josh Cartwright <joshc@codeaurora.org> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Grant Likely <grant.likely@linaro.org> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Josh Cartwright <joshc@codeaurora.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r--mm/cma.c62
1 files changed, 51 insertions, 11 deletions
diff --git a/mm/cma.c b/mm/cma.c
index a951a3b3ed36..963bc4add9af 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -143,6 +143,54 @@ static int __init cma_init_reserved_areas(void)
core_initcall(cma_init_reserved_areas);
/**
+ * cma_init_reserved_mem() - create custom contiguous area from reserved memory
+ * @base: Base address of the reserved area
+ * @size: Size of the reserved area (in bytes),
+ * @order_per_bit: Order of pages represented by one bit on bitmap.
+ * @res_cma: Pointer to store the created cma region.
+ *
+ * This function creates custom contiguous area from already reserved memory.
+ */
+int __init cma_init_reserved_mem(phys_addr_t base, phys_addr_t size,
+ int order_per_bit, struct cma **res_cma)
+{
+ struct cma *cma;
+ phys_addr_t alignment;
+
+ /* Sanity checks */
+ if (cma_area_count == ARRAY_SIZE(cma_areas)) {
+ pr_err("Not enough slots for CMA reserved regions!\n");
+ return -ENOSPC;
+ }
+
+ if (!size || !memblock_is_region_reserved(base, size))
+ return -EINVAL;
+
+ /* ensure minimal alignment requied by mm core */
+ alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order);
+
+ /* alignment should be aligned with order_per_bit */
+ if (!IS_ALIGNED(alignment >> PAGE_SHIFT, 1 << order_per_bit))
+ return -EINVAL;
+
+ if (ALIGN(base, alignment) != base || ALIGN(size, alignment) != size)
+ return -EINVAL;
+
+ /*
+ * Each reserved area must be initialised later, when more kernel
+ * subsystems (like slab allocator) are available.
+ */
+ cma = &cma_areas[cma_area_count];
+ cma->base_pfn = PFN_DOWN(base);
+ cma->count = size >> PAGE_SHIFT;
+ cma->order_per_bit = order_per_bit;
+ *res_cma = cma;
+ cma_area_count++;
+
+ return 0;
+}
+
+/**
* cma_declare_contiguous() - reserve custom contiguous area
* @base: Base address of the reserved area optional, use 0 for any
* @size: Size of the reserved area (in bytes),
@@ -165,7 +213,6 @@ int __init cma_declare_contiguous(phys_addr_t base,
phys_addr_t alignment, unsigned int order_per_bit,
bool fixed, struct cma **res_cma)
{
- struct cma *cma;
phys_addr_t memblock_end = memblock_end_of_DRAM();
phys_addr_t highmem_start = __pa(high_memory);
int ret = 0;
@@ -237,16 +284,9 @@ int __init cma_declare_contiguous(phys_addr_t base,
}
}
- /*
- * Each reserved area must be initialised later, when more kernel
- * subsystems (like slab allocator) are available.
- */
- cma = &cma_areas[cma_area_count];
- cma->base_pfn = PFN_DOWN(base);
- cma->count = size >> PAGE_SHIFT;
- cma->order_per_bit = order_per_bit;
- *res_cma = cma;
- cma_area_count++;
+ ret = cma_init_reserved_mem(base, size, order_per_bit, res_cma);
+ if (ret)
+ goto err;
pr_info("Reserved %ld MiB at %08lx\n", (unsigned long)size / SZ_1M,
(unsigned long)base);

Privacy Policy