aboutsummaryrefslogtreecommitdiffstats
path: root/roms/u-boot/include/linux/dma-mapping.h
diff options
context:
space:
mode:
authorAngelos Mouzakitis <a.mouzakitis@virtualopensystems.com>2023-10-10 14:33:42 +0000
committerAngelos Mouzakitis <a.mouzakitis@virtualopensystems.com>2023-10-10 14:33:42 +0000
commitaf1a266670d040d2f4083ff309d732d648afba2a (patch)
tree2fc46203448ddcc6f81546d379abfaeb323575e9 /roms/u-boot/include/linux/dma-mapping.h
parente02cda008591317b1625707ff8e115a4841aa889 (diff)
Add submodule dependency filesHEADmaster
Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec
Diffstat (limited to 'roms/u-boot/include/linux/dma-mapping.h')
-rw-r--r--roms/u-boot/include/linux/dma-mapping.h64
1 files changed, 64 insertions, 0 deletions
diff --git a/roms/u-boot/include/linux/dma-mapping.h b/roms/u-boot/include/linux/dma-mapping.h
new file mode 100644
index 000000000..6a107d52e
--- /dev/null
+++ b/roms/u-boot/include/linux/dma-mapping.h
@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_DMA_MAPPING_H
+#define _LINUX_DMA_MAPPING_H
+
+#include <asm/cache.h>
+#include <linux/dma-direction.h>
+#include <linux/types.h>
+#include <asm/dma-mapping.h>
+#include <cpu_func.h>
+
+#define dma_mapping_error(x, y) 0
+
+/**
+ * Map a buffer to make it available to the DMA device
+ *
+ * Linux-like DMA API that is intended to be used from drivers. This hides the
+ * underlying cache operation from drivers. Call this before starting the DMA
+ * transfer. In most of architectures in U-Boot, the virtual address matches to
+ * the physical address (but we have exceptions like sandbox). U-Boot does not
+ * support iommu at the driver level, so it also matches to the DMA address.
+ * Hence, this helper currently just performs the cache operation, then returns
+ * straight-mapped dma_address, which is intended to be set to the register of
+ * the DMA device.
+ *
+ * @vaddr: address of the buffer
+ * @len: length of the buffer
+ * @dir: the direction of DMA
+ */
+static inline dma_addr_t dma_map_single(void *vaddr, size_t len,
+ enum dma_data_direction dir)
+{
+ unsigned long addr = (unsigned long)vaddr;
+
+ len = ALIGN(len, ARCH_DMA_MINALIGN);
+
+ if (dir == DMA_FROM_DEVICE)
+ invalidate_dcache_range(addr, addr + len);
+ else
+ flush_dcache_range(addr, addr + len);
+
+ return addr;
+}
+
+/**
+ * Unmap a buffer to make it available to CPU
+ *
+ * Linux-like DMA API that is intended to be used from drivers. This hides the
+ * underlying cache operation from drivers. Call this after finishin the DMA
+ * transfer.
+ *
+ * @addr: DMA address
+ * @len: length of the buffer
+ * @dir: the direction of DMA
+ */
+static inline void dma_unmap_single(dma_addr_t addr, size_t len,
+ enum dma_data_direction dir)
+{
+ len = ALIGN(len, ARCH_DMA_MINALIGN);
+
+ if (dir != DMA_TO_DEVICE)
+ invalidate_dcache_range(addr, addr + len);
+}
+
+#endif