[PATCH 1/3] dma-mapping: introduce new dma unmap and sync api variants

From: Laurentiu Tudor
Date: Thu Oct 24 2019 - 06:55:55 EST


From: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>

Introduce a few new dma unmap and sync variants that, on top of the
original variants, return the physical address corresponding to the
input dma address.
In order to implement this a new dma map op is added and used:
phys_addr_t get_phys_addr(dev, dma_handle);
It does the actual conversion of an input dma address to the output
physical address.

Signed-off-by: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>
---
include/linux/dma-mapping.h | 55 +++++++++++++++++++++++++++++++++++++
1 file changed, 55 insertions(+)

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 4a1c4fca475a..d2bccb814eac 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -132,6 +132,7 @@ struct dma_map_ops {
u64 (*get_required_mask)(struct device *dev);
size_t (*max_mapping_size)(struct device *dev);
unsigned long (*get_merge_boundary)(struct device *dev);
+ phys_addr_t (*get_phys_addr)(struct device *dev, dma_addr_t dma_handle);
};

#define DMA_MAPPING_ERROR (~(dma_addr_t)0)
@@ -304,6 +305,21 @@ static inline void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr,
debug_dma_unmap_page(dev, addr, size, dir);
}

+static inline phys_addr_t
+dma_unmap_page_phys_attrs(struct device *dev, dma_addr_t addr, size_t size,
+ enum dma_data_direction dir, unsigned long attrs)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ phys_addr_t phys = 0;
+
+ if (ops && ops->get_phys_addr)
+ phys = ops->get_phys_addr(dev, addr);
+
+ dma_unmap_page_attrs(dev, addr, size, dir, attrs);
+
+ return phys;
+}
+
/*
* dma_maps_sg_attrs returns 0 on error and > 0 on success.
* It should never return a value < 0.
@@ -390,6 +406,21 @@ static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
debug_dma_sync_single_for_cpu(dev, addr, size, dir);
}

+static inline phys_addr_t
+dma_sync_single_for_cpu_phys(struct device *dev, dma_addr_t addr, size_t size,
+ enum dma_data_direction dir)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ phys_addr_t phys = 0;
+
+ if (ops && ops->get_phys_addr)
+ phys = ops->get_phys_addr(dev, addr);
+
+ dma_sync_single_for_cpu(dev, addr, size, dir);
+
+ return phys;
+}
+
static inline void dma_sync_single_for_device(struct device *dev,
dma_addr_t addr, size_t size,
enum dma_data_direction dir)
@@ -500,6 +531,12 @@ static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
size_t size, enum dma_data_direction dir)
{
}
+
+static inline phys_addr_t
+dma_sync_single_for_cpu_phys(struct device *dev, dma_addr_t addr, size_t size,
+ enum dma_data_direction dir)
+{
+}
static inline void dma_sync_single_for_device(struct device *dev,
dma_addr_t addr, size_t size, enum dma_data_direction dir)
{
@@ -594,6 +631,21 @@ static inline void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
return dma_unmap_page_attrs(dev, addr, size, dir, attrs);
}

+static inline phys_addr_t
+dma_unmap_single_phys_attrs(struct device *dev, dma_addr_t addr, size_t size,
+ enum dma_data_direction dir, unsigned long attrs)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ phys_addr_t phys = 0;
+
+ if (ops && ops->get_phys_addr)
+ phys = ops->get_phys_addr(dev, addr);
+
+ dma_unmap_single_attrs(dev, addr, size, dir, attrs);
+
+ return phys;
+}
+
static inline void dma_sync_single_range_for_cpu(struct device *dev,
dma_addr_t addr, unsigned long offset, size_t size,
enum dma_data_direction dir)
@@ -610,10 +662,13 @@ static inline void dma_sync_single_range_for_device(struct device *dev,

#define dma_map_single(d, a, s, r) dma_map_single_attrs(d, a, s, r, 0)
#define dma_unmap_single(d, a, s, r) dma_unmap_single_attrs(d, a, s, r, 0)
+#define dma_unmap_single_phys(d, a, s, r) \
+ dma_unmap_single_phys_attrs(d, a, s, r, 0)
#define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0)
#define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0)
#define dma_map_page(d, p, o, s, r) dma_map_page_attrs(d, p, o, s, r, 0)
#define dma_unmap_page(d, a, s, r) dma_unmap_page_attrs(d, a, s, r, 0)
+#define dma_unmap_page_phys(d, a, s, r) dma_unmap_page_phys_attrs(d, a, s, r, 0)
#define dma_get_sgtable(d, t, v, h, s) dma_get_sgtable_attrs(d, t, v, h, s, 0)
#define dma_mmap_coherent(d, v, c, h, s) dma_mmap_attrs(d, v, c, h, s, 0)

--
2.17.1