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1/*
2 * Port on Texas Instruments TMS320C6x architecture
3 *
4 * Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
5 * Author: Aurelien Jacquiot <aurelien.jacquiot@ti.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * DMA uncached mapping support.
12 *
13 * Using code pulled from ARM
14 * Copyright (C) 2000-2004 Russell King
15 *
16 */
17#include <linux/slab.h>
18#include <linux/bitmap.h>
19#include <linux/bitops.h>
20#include <linux/module.h>
21#include <linux/interrupt.h>
22#include <linux/dma-mapping.h>
23#include <linux/memblock.h>
24
25#include <asm/page.h>
26
27/*
28 * DMA coherent memory management, can be redefined using the memdma=
29 * kernel command line
30 */
31
32/* none by default */
33static phys_addr_t dma_base;
34static u32 dma_size;
35static u32 dma_pages;
36
37static unsigned long *dma_bitmap;
38
39/* bitmap lock */
40static DEFINE_SPINLOCK(dma_lock);
41
42/*
43 * Return a DMA coherent and contiguous memory chunk from the DMA memory
44 */
45static inline u32 __alloc_dma_pages(int order)
46{
47 unsigned long flags;
48 u32 pos;
49
50 spin_lock_irqsave(&dma_lock, flags);
51 pos = bitmap_find_free_region(dma_bitmap, dma_pages, order);
52 spin_unlock_irqrestore(&dma_lock, flags);
53
54 return dma_base + (pos << PAGE_SHIFT);
55}
56
57static void __free_dma_pages(u32 addr, int order)
58{
59 unsigned long flags;
60 u32 pos = (addr - dma_base) >> PAGE_SHIFT;
61
62 if (addr < dma_base || (pos + (1 << order)) >= dma_pages) {
63 printk(KERN_ERR "%s: freeing outside range.\n", __func__);
64 BUG();
65 }
66
67 spin_lock_irqsave(&dma_lock, flags);
68 bitmap_release_region(dma_bitmap, pos, order);
69 spin_unlock_irqrestore(&dma_lock, flags);
70}
71
72/*
73 * Allocate DMA coherent memory space and return both the kernel
74 * virtual and DMA address for that space.
75 */
76void *c6x_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
77 gfp_t gfp, unsigned long attrs)
78{
79 u32 paddr;
80 int order;
81
82 if (!dma_size || !size)
83 return NULL;
84
85 order = get_count_order(((size - 1) >> PAGE_SHIFT) + 1);
86
87 paddr = __alloc_dma_pages(order);
88
89 if (handle)
90 *handle = paddr;
91
92 if (!paddr)
93 return NULL;
94
95 return phys_to_virt(paddr);
96}
97
98/*
99 * Free DMA coherent memory as defined by the above mapping.
100 */
101void c6x_dma_free(struct device *dev, size_t size, void *vaddr,
102 dma_addr_t dma_handle, unsigned long attrs)
103{
104 int order;
105
106 if (!dma_size || !size)
107 return;
108
109 order = get_count_order(((size - 1) >> PAGE_SHIFT) + 1);
110
111 __free_dma_pages(virt_to_phys(vaddr), order);
112}
113
114/*
115 * Initialise the coherent DMA memory allocator using the given uncached region.
116 */
117void __init coherent_mem_init(phys_addr_t start, u32 size)
118{
119 phys_addr_t bitmap_phys;
120
121 if (!size)
122 return;
123
124 printk(KERN_INFO
125 "Coherent memory (DMA) region start=0x%x size=0x%x\n",
126 start, size);
127
128 dma_base = start;
129 dma_size = size;
130
131 /* allocate bitmap */
132 dma_pages = dma_size >> PAGE_SHIFT;
133 if (dma_size & (PAGE_SIZE - 1))
134 ++dma_pages;
135
136 bitmap_phys = memblock_alloc(BITS_TO_LONGS(dma_pages) * sizeof(long),
137 sizeof(long));
138
139 dma_bitmap = phys_to_virt(bitmap_phys);
140 memset(dma_bitmap, 0, dma_pages * PAGE_SIZE);
141}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Port on Texas Instruments TMS320C6x architecture
4 *
5 * Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
6 * Author: Aurelien Jacquiot <aurelien.jacquiot@ti.com>
7 *
8 * DMA uncached mapping support.
9 *
10 * Using code pulled from ARM
11 * Copyright (C) 2000-2004 Russell King
12 */
13#include <linux/slab.h>
14#include <linux/bitmap.h>
15#include <linux/bitops.h>
16#include <linux/module.h>
17#include <linux/interrupt.h>
18#include <linux/dma-noncoherent.h>
19#include <linux/memblock.h>
20
21#include <asm/cacheflush.h>
22#include <asm/page.h>
23#include <asm/setup.h>
24
25/*
26 * DMA coherent memory management, can be redefined using the memdma=
27 * kernel command line
28 */
29
30/* none by default */
31static phys_addr_t dma_base;
32static u32 dma_size;
33static u32 dma_pages;
34
35static unsigned long *dma_bitmap;
36
37/* bitmap lock */
38static DEFINE_SPINLOCK(dma_lock);
39
40/*
41 * Return a DMA coherent and contiguous memory chunk from the DMA memory
42 */
43static inline u32 __alloc_dma_pages(int order)
44{
45 unsigned long flags;
46 u32 pos;
47
48 spin_lock_irqsave(&dma_lock, flags);
49 pos = bitmap_find_free_region(dma_bitmap, dma_pages, order);
50 spin_unlock_irqrestore(&dma_lock, flags);
51
52 return dma_base + (pos << PAGE_SHIFT);
53}
54
55static void __free_dma_pages(u32 addr, int order)
56{
57 unsigned long flags;
58 u32 pos = (addr - dma_base) >> PAGE_SHIFT;
59
60 if (addr < dma_base || (pos + (1 << order)) >= dma_pages) {
61 printk(KERN_ERR "%s: freeing outside range.\n", __func__);
62 BUG();
63 }
64
65 spin_lock_irqsave(&dma_lock, flags);
66 bitmap_release_region(dma_bitmap, pos, order);
67 spin_unlock_irqrestore(&dma_lock, flags);
68}
69
70/*
71 * Allocate DMA coherent memory space and return both the kernel
72 * virtual and DMA address for that space.
73 */
74void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
75 gfp_t gfp, unsigned long attrs)
76{
77 void *ret;
78 u32 paddr;
79 int order;
80
81 if (!dma_size || !size)
82 return NULL;
83
84 order = get_count_order(((size - 1) >> PAGE_SHIFT) + 1);
85
86 paddr = __alloc_dma_pages(order);
87
88 if (handle)
89 *handle = paddr;
90
91 if (!paddr)
92 return NULL;
93
94 ret = phys_to_virt(paddr);
95 memset(ret, 0, 1 << order);
96 return ret;
97}
98
99/*
100 * Free DMA coherent memory as defined by the above mapping.
101 */
102void arch_dma_free(struct device *dev, size_t size, void *vaddr,
103 dma_addr_t dma_handle, unsigned long attrs)
104{
105 int order;
106
107 if (!dma_size || !size)
108 return;
109
110 order = get_count_order(((size - 1) >> PAGE_SHIFT) + 1);
111
112 __free_dma_pages(virt_to_phys(vaddr), order);
113}
114
115/*
116 * Initialise the coherent DMA memory allocator using the given uncached region.
117 */
118void __init coherent_mem_init(phys_addr_t start, u32 size)
119{
120 if (!size)
121 return;
122
123 printk(KERN_INFO
124 "Coherent memory (DMA) region start=0x%x size=0x%x\n",
125 start, size);
126
127 dma_base = start;
128 dma_size = size;
129
130 /* allocate bitmap */
131 dma_pages = dma_size >> PAGE_SHIFT;
132 if (dma_size & (PAGE_SIZE - 1))
133 ++dma_pages;
134
135 dma_bitmap = memblock_alloc(BITS_TO_LONGS(dma_pages) * sizeof(long),
136 sizeof(long));
137 if (!dma_bitmap)
138 panic("%s: Failed to allocate %zu bytes align=0x%zx\n",
139 __func__, BITS_TO_LONGS(dma_pages) * sizeof(long),
140 sizeof(long));
141}
142
143static void c6x_dma_sync(phys_addr_t paddr, size_t size,
144 enum dma_data_direction dir)
145{
146 BUG_ON(!valid_dma_direction(dir));
147
148 switch (dir) {
149 case DMA_FROM_DEVICE:
150 L2_cache_block_invalidate(paddr, paddr + size);
151 break;
152 case DMA_TO_DEVICE:
153 L2_cache_block_writeback(paddr, paddr + size);
154 break;
155 case DMA_BIDIRECTIONAL:
156 L2_cache_block_writeback_invalidate(paddr, paddr + size);
157 break;
158 default:
159 break;
160 }
161}
162
163void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
164 enum dma_data_direction dir)
165{
166 return c6x_dma_sync(paddr, size, dir);
167}
168
169void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
170 enum dma_data_direction dir)
171{
172 return c6x_dma_sync(paddr, size, dir);
173}