From 1ca8d4889a376b9a98d00cb1af42e782cbba5334 Mon Sep 17 00:00:00 2001
From: Laura Abbott <lauraa@codeaurora.org>
Date: Mon, 3 Jun 2013 19:14:08 -0700
Subject: [PATCH] cma: Add API to get the start address of a CMA region
When setting CMA up at a fixed region, it is possible for the address
to be shared between multiple subsystems. If the address is placed
dynamically, there is no mechanism to be able to get the start address
of the region. Drivers may wish to do keep track of allocations relative
to the start address so add an API to get the start region of a CMA
address.
Change-Id: If0730c64496c876d3143064d767b22b984c6dc84
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
---
drivers/base/dma-contiguous.c | 7 +++++++
include/linux/dma-contiguous.h | 9 +++++++++
2 files changed, 16 insertions(+)
diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index b71e50bbfc78..3baca0e1b37b 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c
@@ -461,6 +461,13 @@ static int __init cma_init_reserved_areas(void)
}
core_initcall(cma_init_reserved_areas);
+phys_addr_t cma_get_base(struct device *dev)
+{
+ struct cma *cma = dev_get_cma_area(dev);
+
+ return cma->base_pfn << PAGE_SHIFT;
+}
+
/**
* dma_alloc_from_contiguous() - allocate pages from contiguous area
* @dev: Pointer to device for which the allocation is performed.
diff --git a/include/linux/dma-contiguous.h b/include/linux/dma-contiguous.h
index e5ebd7e16ac8..9975eef4cad7 100644
--- a/include/linux/dma-contiguous.h
+++ b/include/linux/dma-contiguous.h
@@ -65,6 +65,9 @@ struct device;
*/
#define MAX_CMA_AREAS (1 + CONFIG_CMA_AREAS)
+
+phys_addr_t cma_get_base(struct device *dev);
+
extern struct cma *dma_contiguous_def_area;
void dma_contiguous_reserve(phys_addr_t addr_limit);
@@ -142,6 +145,12 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages,
return false;
}
+
+static inline phys_addr_t cma_get_base(struct device *dev)
+{
+ return 0;
+}
+
#endif
#endif
--
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