1 files changed, 83 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/common/bouncebuf.c b/qemu/roms/u-boot/common/bouncebuf.c
new file mode 100644
index 000000000..9eece6d75
--- /dev/null
+++ b/qemu/roms/u-boot/common/bouncebuf.c
@@ -0,0 +1,83 @@
+/*
+ * Generic bounce buffer implementation
+ *
+ * Copyright (C) 2012 Marek Vasut <marex@denx.de>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <errno.h>
+#include <bouncebuf.h>
+
+static int addr_aligned(struct bounce_buffer *state)
+{
+	const ulong align_mask = ARCH_DMA_MINALIGN - 1;
+
+	/* Check if start is aligned */
+	if ((ulong)state->user_buffer & align_mask) {
+		debug("Unaligned buffer address %p\n", state->user_buffer);
+		return 0;
+	}
+
+	/* Check if length is aligned */
+	if (state->len != state->len_aligned) {
+		debug("Unaligned buffer length %d\n", state->len);
+		return 0;
+	}
+
+	/* Aligned */
+	return 1;
+}
+
+int bounce_buffer_start(struct bounce_buffer *state, void *data,
+			size_t len, unsigned int flags)
+{
+	state->user_buffer = data;
+	state->bounce_buffer = data;
+	state->len = len;
+	state->len_aligned = roundup(len, ARCH_DMA_MINALIGN);
+	state->flags = flags;
+
+	if (!addr_aligned(state)) {
+		state->bounce_buffer = memalign(ARCH_DMA_MINALIGN,
+						state->len_aligned);
+		if (!state->bounce_buffer)
+			return -ENOMEM;
+
+		if (state->flags & GEN_BB_READ)
+			memcpy(state->bounce_buffer, state->user_buffer,
+				state->len);
+	}
+
+	/*
+	 * Flush data to RAM so DMA reads can pick it up,
+	 * and any CPU writebacks don't race with DMA writes
+	 */
+	flush_dcache_range((unsigned long)state->bounce_buffer,
+				(unsigned long)(state->bounce_buffer) +
+					state->len_aligned);
+
+	return 0;
+}
+
+int bounce_buffer_stop(struct bounce_buffer *state)
+{
+	if (state->flags & GEN_BB_WRITE) {
+		/* Invalidate cache so that CPU can see any newly DMA'd data */
+		invalidate_dcache_range((unsigned long)state->bounce_buffer,
+					(unsigned long)(state->bounce_buffer) +
+						state->len_aligned);
+	}
+
+	if (state->bounce_buffer == state->user_buffer)
+		return 0;
+
+	if (state->flags & GEN_BB_WRITE)
+		memcpy(state->user_buffer, state->bounce_buffer, state->len);
+
+	free(state->bounce_buffer);
+
+	return 0;
+}