Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * DMA memory management for framework level HCD code (hc_driver) | |
3 | * | |
4 | * This implementation plugs in through generic "usb_bus" level methods, | |
5 | * and should work with all USB controllers, regardles of bus type. | |
6 | */ | |
7 | ||
1da177e4 LT |
8 | #include <linux/module.h> |
9 | #include <linux/kernel.h> | |
10 | #include <linux/slab.h> | |
11 | #include <linux/device.h> | |
12 | #include <linux/mm.h> | |
13 | #include <asm/io.h> | |
14 | #include <asm/scatterlist.h> | |
15 | #include <linux/dma-mapping.h> | |
16 | #include <linux/dmapool.h> | |
1da177e4 LT |
17 | #include <linux/usb.h> |
18 | #include "hcd.h" | |
19 | ||
20 | ||
21 | /* | |
22 | * DMA-Coherent Buffers | |
23 | */ | |
24 | ||
25 | /* FIXME tune these based on pool statistics ... */ | |
26 | static const size_t pool_max [HCD_BUFFER_POOLS] = { | |
27 | /* platforms without dma-friendly caches might need to | |
28 | * prevent cacheline sharing... | |
29 | */ | |
30 | 32, | |
31 | 128, | |
32 | 512, | |
33 | PAGE_SIZE / 2 | |
34 | /* bigger --> allocate pages */ | |
35 | }; | |
36 | ||
37 | ||
38 | /* SETUP primitives */ | |
39 | ||
40 | /** | |
41 | * hcd_buffer_create - initialize buffer pools | |
42 | * @hcd: the bus whose buffer pools are to be initialized | |
43 | * Context: !in_interrupt() | |
44 | * | |
45 | * Call this as part of initializing a host controller that uses the dma | |
46 | * memory allocators. It initializes some pools of dma-coherent memory that | |
47 | * will be shared by all drivers using that controller, or returns a negative | |
48 | * errno value on error. | |
49 | * | |
50 | * Call hcd_buffer_destroy() to clean up after using those pools. | |
51 | */ | |
1a68f71d | 52 | int hcd_buffer_create(struct usb_hcd *hcd) |
1da177e4 | 53 | { |
1a68f71d | 54 | char name[16]; |
1da177e4 LT |
55 | int i, size; |
56 | ||
bd39b7f1 CH |
57 | if (!hcd->self.controller->dma_mask) |
58 | return 0; | |
59 | ||
1da177e4 LT |
60 | for (i = 0; i < HCD_BUFFER_POOLS; i++) { |
61 | if (!(size = pool_max [i])) | |
62 | continue; | |
1a68f71d ON |
63 | snprintf(name, sizeof name, "buffer-%d", size); |
64 | hcd->pool[i] = dma_pool_create(name, hcd->self.controller, | |
1da177e4 LT |
65 | size, size, 0); |
66 | if (!hcd->pool [i]) { | |
1a68f71d | 67 | hcd_buffer_destroy(hcd); |
1da177e4 LT |
68 | return -ENOMEM; |
69 | } | |
70 | } | |
71 | return 0; | |
72 | } | |
73 | ||
74 | ||
75 | /** | |
76 | * hcd_buffer_destroy - deallocate buffer pools | |
77 | * @hcd: the bus whose buffer pools are to be destroyed | |
78 | * Context: !in_interrupt() | |
79 | * | |
80 | * This frees the buffer pools created by hcd_buffer_create(). | |
81 | */ | |
1a68f71d | 82 | void hcd_buffer_destroy(struct usb_hcd *hcd) |
1da177e4 LT |
83 | { |
84 | int i; | |
85 | ||
86 | for (i = 0; i < HCD_BUFFER_POOLS; i++) { | |
1a68f71d | 87 | struct dma_pool *pool = hcd->pool[i]; |
1da177e4 | 88 | if (pool) { |
1a68f71d | 89 | dma_pool_destroy(pool); |
1da177e4 LT |
90 | hcd->pool[i] = NULL; |
91 | } | |
92 | } | |
93 | } | |
94 | ||
95 | ||
441e143e | 96 | /* sometimes alloc/free could use kmalloc with GFP_DMA, for |
1da177e4 LT |
97 | * better sharing and to leverage mm/slab.c intelligence. |
98 | */ | |
99 | ||
1a68f71d ON |
100 | void *hcd_buffer_alloc( |
101 | struct usb_bus *bus, | |
1da177e4 | 102 | size_t size, |
55016f10 | 103 | gfp_t mem_flags, |
1da177e4 LT |
104 | dma_addr_t *dma |
105 | ) | |
106 | { | |
17200583 | 107 | struct usb_hcd *hcd = bus_to_hcd(bus); |
1da177e4 LT |
108 | int i; |
109 | ||
110 | /* some USB hosts just use PIO */ | |
111 | if (!bus->controller->dma_mask) { | |
112 | *dma = ~(dma_addr_t) 0; | |
1a68f71d | 113 | return kmalloc(size, mem_flags); |
1da177e4 LT |
114 | } |
115 | ||
116 | for (i = 0; i < HCD_BUFFER_POOLS; i++) { | |
117 | if (size <= pool_max [i]) | |
1a68f71d | 118 | return dma_pool_alloc(hcd->pool [i], mem_flags, dma); |
1da177e4 | 119 | } |
1a68f71d | 120 | return dma_alloc_coherent(hcd->self.controller, size, dma, 0); |
1da177e4 LT |
121 | } |
122 | ||
1a68f71d ON |
123 | void hcd_buffer_free( |
124 | struct usb_bus *bus, | |
1da177e4 LT |
125 | size_t size, |
126 | void *addr, | |
127 | dma_addr_t dma | |
128 | ) | |
129 | { | |
17200583 | 130 | struct usb_hcd *hcd = bus_to_hcd(bus); |
1da177e4 LT |
131 | int i; |
132 | ||
133 | if (!addr) | |
134 | return; | |
135 | ||
136 | if (!bus->controller->dma_mask) { | |
1a68f71d | 137 | kfree(addr); |
1da177e4 LT |
138 | return; |
139 | } | |
140 | ||
141 | for (i = 0; i < HCD_BUFFER_POOLS; i++) { | |
142 | if (size <= pool_max [i]) { | |
1a68f71d | 143 | dma_pool_free(hcd->pool [i], addr, dma); |
1da177e4 LT |
144 | return; |
145 | } | |
146 | } | |
1a68f71d | 147 | dma_free_coherent(hcd->self.controller, size, addr, dma); |
1da177e4 | 148 | } |