sandbox: asm: implement stub DMA functions

For compile-testing drivers that use DMA operations under sandbox,
we want stub implementations of these. Provide them.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 52 insertions, 1 deletions

diff --git a/arch/sandbox/include/asm/dma.h b/arch/sandbox/include/asm/dma.h
index 459536779e..5e72d8e7df 100644
--- a/arch/sandbox/include/asm/dma.h
+++ b/arch/sandbox/include/asm/dma.h
@@ -8,6 +8,57 @@
 #ifndef __ASM_DMA_H
 #define __ASM_DMA_H
 
-/* empty*/
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <driver.h>
+
+#define dma_alloc dma_alloc
+static inline void *dma_alloc(size_t size)
+{
+	return xmemalign(64, ALIGN(size, 64));
+}
+
+static inline void *dma_alloc_coherent(size_t size, dma_addr_t *dma_handle)
+{
+	void *ret = xmemalign(4096, size);
+	if (dma_handle)
+		*dma_handle = (dma_addr_t)ret;
+
+	memset(ret, 0, size);
+
+	return ret;
+}
+
+static inline void *dma_alloc_writecombine(size_t size, dma_addr_t *dma_handle)
+{
+	return dma_alloc_coherent(size, dma_handle);
+}
+
+static inline void dma_free_coherent(void *mem, dma_addr_t dma_handle,
+				     size_t size)
+{
+	free(mem);
+}
+
+static inline dma_addr_t dma_map_single(struct device_d *dev, void *ptr, size_t size,
+					enum dma_data_direction dir)
+{
+	return (dma_addr_t)ptr;
+}
+
+static inline void dma_unmap_single(struct device_d *dev, dma_addr_t addr, size_t size,
+				    enum dma_data_direction dir)
+{
+}
+
+static inline void dma_sync_single_for_cpu(dma_addr_t address, size_t size,
+					   enum dma_data_direction dir)
+{
+}
+
+static inline void dma_sync_single_for_device(dma_addr_t address, size_t size,
+					      enum dma_data_direction dir)
+{
+}
 
 #endif /* __ASM_DMA_H */