mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-06-09 23:36:03 +09:00
83d290c56f
When U-Boot started using SPDX tags we were among the early adopters and there weren't a lot of other examples to borrow from. So we picked the area of the file that usually had a full license text and replaced it with an appropriate SPDX-License-Identifier: entry. Since then, the Linux Kernel has adopted SPDX tags and they place it as the very first line in a file (except where shebangs are used, then it's second line) and with slightly different comment styles than us. In part due to community overlap, in part due to better tag visibility and in part for other minor reasons, switch over to that style. This commit changes all instances where we have a single declared license in the tag as both the before and after are identical in tag contents. There's also a few places where I found we did not have a tag and have introduced one. Signed-off-by: Tom Rini <trini@konsulko.com>
83 lines
1.9 KiB
C
83 lines
1.9 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* Generic bounce buffer implementation
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*
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* Copyright (C) 2012 Marek Vasut <marex@denx.de>
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*/
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#include <common.h>
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#include <malloc.h>
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#include <errno.h>
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#include <bouncebuf.h>
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static int addr_aligned(struct bounce_buffer *state)
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{
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const ulong align_mask = ARCH_DMA_MINALIGN - 1;
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/* Check if start is aligned */
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if ((ulong)state->user_buffer & align_mask) {
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debug("Unaligned buffer address %p\n", state->user_buffer);
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return 0;
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}
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/* Check if length is aligned */
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if (state->len != state->len_aligned) {
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debug("Unaligned buffer length %zu\n", state->len);
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return 0;
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}
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/* Aligned */
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return 1;
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}
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int bounce_buffer_start(struct bounce_buffer *state, void *data,
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size_t len, unsigned int flags)
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{
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state->user_buffer = data;
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state->bounce_buffer = data;
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state->len = len;
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state->len_aligned = roundup(len, ARCH_DMA_MINALIGN);
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state->flags = flags;
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if (!addr_aligned(state)) {
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state->bounce_buffer = memalign(ARCH_DMA_MINALIGN,
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state->len_aligned);
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if (!state->bounce_buffer)
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return -ENOMEM;
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if (state->flags & GEN_BB_READ)
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memcpy(state->bounce_buffer, state->user_buffer,
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state->len);
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}
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/*
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* Flush data to RAM so DMA reads can pick it up,
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* and any CPU writebacks don't race with DMA writes
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*/
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flush_dcache_range((unsigned long)state->bounce_buffer,
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(unsigned long)(state->bounce_buffer) +
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state->len_aligned);
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return 0;
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}
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int bounce_buffer_stop(struct bounce_buffer *state)
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{
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if (state->flags & GEN_BB_WRITE) {
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/* Invalidate cache so that CPU can see any newly DMA'd data */
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invalidate_dcache_range((unsigned long)state->bounce_buffer,
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(unsigned long)(state->bounce_buffer) +
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state->len_aligned);
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}
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if (state->bounce_buffer == state->user_buffer)
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return 0;
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if (state->flags & GEN_BB_WRITE)
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memcpy(state->user_buffer, state->bounce_buffer, state->len);
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free(state->bounce_buffer);
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return 0;
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}
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