1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* RISC-V specific functions to support DMA for non-coherent devices
*
* Copyright (c) 2021 Western Digital Corporation or its affiliates.
*/
#include <linux/dma-direct.h>
#include <linux/dma-map-ops.h>
#include <linux/mm.h>
#include <asm/cacheflush.h>
static bool noncoherent_supported;
void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
enum dma_data_direction dir)
{
void *vaddr = phys_to_virt(paddr);
switch (dir) {
case DMA_TO_DEVICE:
ALT_CMO_OP(clean, vaddr, size, riscv_cbom_block_size);
break;
case DMA_FROM_DEVICE:
ALT_CMO_OP(clean, vaddr, size, riscv_cbom_block_size);
break;
case DMA_BIDIRECTIONAL:
ALT_CMO_OP(flush, vaddr, size, riscv_cbom_block_size);
break;
default:
break;
}
}
void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
enum dma_data_direction dir)
{
void *vaddr = phys_to_virt(paddr);
switch (dir) {
case DMA_TO_DEVICE:
break;
case DMA_FROM_DEVICE:
case DMA_BIDIRECTIONAL:
ALT_CMO_OP(flush, vaddr, size, riscv_cbom_block_size);
break;
default:
break;
}
}
void arch_dma_prep_coherent(struct page *page, size_t size)
{
void *flush_addr = page_address(page);
ALT_CMO_OP(flush, flush_addr, size, riscv_cbom_block_size);
}
void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
const struct iommu_ops *iommu, bool coherent)
{
WARN_TAINT(!coherent && riscv_cbom_block_size > ARCH_DMA_MINALIGN,
TAINT_CPU_OUT_OF_SPEC,
"%s %s: ARCH_DMA_MINALIGN smaller than riscv,cbom-block-size (%d < %d)",
dev_driver_string(dev), dev_name(dev),
ARCH_DMA_MINALIGN, riscv_cbom_block_size);
WARN_TAINT(!coherent && !noncoherent_supported, TAINT_CPU_OUT_OF_SPEC,
"%s %s: device non-coherent but no non-coherent operations supported",
dev_driver_string(dev), dev_name(dev));
dev->dma_coherent = coherent;
}
void riscv_noncoherent_supported(void)
{
WARN(!riscv_cbom_block_size,
"Non-coherent DMA support enabled without a block size\n");
noncoherent_supported = true;
}
|
