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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
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 <linux/io.h>
14#include <linux/dma-mapping.h>
15#include <linux/dmapool.h>
16#include <linux/usb.h>
17#include <linux/usb/hcd.h>
18
19
20/*
21 * DMA-Coherent Buffers
22 */
23
24/* FIXME tune these based on pool statistics ... */
25static const size_t pool_max[HCD_BUFFER_POOLS] = {
26 /* platforms without dma-friendly caches might need to
27 * prevent cacheline sharing...
28 */
29 32,
30 128,
31 512,
32 PAGE_SIZE / 2
33 /* bigger --> allocate pages */
34};
35
36
37/* SETUP primitives */
38
39/**
40 * hcd_buffer_create - initialize buffer pools
41 * @hcd: the bus whose buffer pools are to be initialized
42 * Context: !in_interrupt()
43 *
44 * Call this as part of initializing a host controller that uses the dma
45 * memory allocators. It initializes some pools of dma-coherent memory that
46 * will be shared by all drivers using that controller, or returns a negative
47 * errno value on error.
48 *
49 * Call hcd_buffer_destroy() to clean up after using those pools.
50 */
51int hcd_buffer_create(struct usb_hcd *hcd)
52{
53 char name[16];
54 int i, size;
55
56 if (!hcd->self.controller->dma_mask &&
57 !(hcd->driver->flags & HCD_LOCAL_MEM))
58 return 0;
59
60 for (i = 0; i < HCD_BUFFER_POOLS; i++) {
61 size = pool_max[i];
62 if (!size)
63 continue;
64 snprintf(name, sizeof name, "buffer-%d", size);
65 hcd->pool[i] = dma_pool_create(name, hcd->self.controller,
66 size, size, 0);
67 if (!hcd->pool[i]) {
68 hcd_buffer_destroy(hcd);
69 return -ENOMEM;
70 }
71 }
72 return 0;
73}
74
75
76/**
77 * hcd_buffer_destroy - deallocate buffer pools
78 * @hcd: the bus whose buffer pools are to be destroyed
79 * Context: !in_interrupt()
80 *
81 * This frees the buffer pools created by hcd_buffer_create().
82 */
83void hcd_buffer_destroy(struct usb_hcd *hcd)
84{
85 int i;
86
87 for (i = 0; i < HCD_BUFFER_POOLS; i++) {
88 struct dma_pool *pool = hcd->pool[i];
89 if (pool) {
90 dma_pool_destroy(pool);
91 hcd->pool[i] = NULL;
92 }
93 }
94}
95
96
97/* sometimes alloc/free could use kmalloc with GFP_DMA, for
98 * better sharing and to leverage mm/slab.c intelligence.
99 */
100
101void *hcd_buffer_alloc(
102 struct usb_bus *bus,
103 size_t size,
104 gfp_t mem_flags,
105 dma_addr_t *dma
106)
107{
108 struct usb_hcd *hcd = bus_to_hcd(bus);
109 int i;
110
111 /* some USB hosts just use PIO */
112 if (!bus->controller->dma_mask &&
113 !(hcd->driver->flags & HCD_LOCAL_MEM)) {
114 *dma = ~(dma_addr_t) 0;
115 return kmalloc(size, mem_flags);
116 }
117
118 for (i = 0; i < HCD_BUFFER_POOLS; i++) {
119 if (size <= pool_max[i])
120 return dma_pool_alloc(hcd->pool[i], mem_flags, dma);
121 }
122 return dma_alloc_coherent(hcd->self.controller, size, dma, mem_flags);
123}
124
125void hcd_buffer_free(
126 struct usb_bus *bus,
127 size_t size,
128 void *addr,
129 dma_addr_t dma
130)
131{
132 struct usb_hcd *hcd = bus_to_hcd(bus);
133 int i;
134
135 if (!addr)
136 return;
137
138 if (!bus->controller->dma_mask &&
139 !(hcd->driver->flags & HCD_LOCAL_MEM)) {
140 kfree(addr);
141 return;
142 }
143
144 for (i = 0; i < HCD_BUFFER_POOLS; i++) {
145 if (size <= pool_max[i]) {
146 dma_pool_free(hcd->pool[i], addr, dma);
147 return;
148 }
149 }
150 dma_free_coherent(hcd->self.controller, size, addr, dma);
151}
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, regardless of bus type.
6 */
7
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 <linux/io.h>
14#include <linux/dma-mapping.h>
15#include <linux/dmapool.h>
16#include <linux/usb.h>
17#include <linux/usb/hcd.h>
18
19
20/*
21 * DMA-Coherent Buffers
22 */
23
24/* FIXME tune these based on pool statistics ... */
25static size_t pool_max[HCD_BUFFER_POOLS] = {
26 32, 128, 512, 2048,
27};
28
29void __init usb_init_pool_max(void)
30{
31 /*
32 * The pool_max values must never be smaller than
33 * ARCH_KMALLOC_MINALIGN.
34 */
35 if (ARCH_KMALLOC_MINALIGN <= 32)
36 ; /* Original value is okay */
37 else if (ARCH_KMALLOC_MINALIGN <= 64)
38 pool_max[0] = 64;
39 else if (ARCH_KMALLOC_MINALIGN <= 128)
40 pool_max[0] = 0; /* Don't use this pool */
41 else
42 BUILD_BUG(); /* We don't allow this */
43}
44
45/* SETUP primitives */
46
47/**
48 * hcd_buffer_create - initialize buffer pools
49 * @hcd: the bus whose buffer pools are to be initialized
50 * Context: !in_interrupt()
51 *
52 * Call this as part of initializing a host controller that uses the dma
53 * memory allocators. It initializes some pools of dma-coherent memory that
54 * will be shared by all drivers using that controller.
55 *
56 * Call hcd_buffer_destroy() to clean up after using those pools.
57 *
58 * Return: 0 if successful. A negative errno value otherwise.
59 */
60int hcd_buffer_create(struct usb_hcd *hcd)
61{
62 char name[16];
63 int i, size;
64
65 if (!IS_ENABLED(CONFIG_HAS_DMA) ||
66 (!hcd->self.controller->dma_mask &&
67 !(hcd->driver->flags & HCD_LOCAL_MEM)))
68 return 0;
69
70 for (i = 0; i < HCD_BUFFER_POOLS; i++) {
71 size = pool_max[i];
72 if (!size)
73 continue;
74 snprintf(name, sizeof(name), "buffer-%d", size);
75 hcd->pool[i] = dma_pool_create(name, hcd->self.controller,
76 size, size, 0);
77 if (!hcd->pool[i]) {
78 hcd_buffer_destroy(hcd);
79 return -ENOMEM;
80 }
81 }
82 return 0;
83}
84
85
86/**
87 * hcd_buffer_destroy - deallocate buffer pools
88 * @hcd: the bus whose buffer pools are to be destroyed
89 * Context: !in_interrupt()
90 *
91 * This frees the buffer pools created by hcd_buffer_create().
92 */
93void hcd_buffer_destroy(struct usb_hcd *hcd)
94{
95 int i;
96
97 if (!IS_ENABLED(CONFIG_HAS_DMA))
98 return;
99
100 for (i = 0; i < HCD_BUFFER_POOLS; i++) {
101 struct dma_pool *pool = hcd->pool[i];
102
103 if (pool) {
104 dma_pool_destroy(pool);
105 hcd->pool[i] = NULL;
106 }
107 }
108}
109
110
111/* sometimes alloc/free could use kmalloc with GFP_DMA, for
112 * better sharing and to leverage mm/slab.c intelligence.
113 */
114
115void *hcd_buffer_alloc(
116 struct usb_bus *bus,
117 size_t size,
118 gfp_t mem_flags,
119 dma_addr_t *dma
120)
121{
122 struct usb_hcd *hcd = bus_to_hcd(bus);
123 int i;
124
125 /* some USB hosts just use PIO */
126 if (!IS_ENABLED(CONFIG_HAS_DMA) ||
127 (!bus->controller->dma_mask &&
128 !(hcd->driver->flags & HCD_LOCAL_MEM))) {
129 *dma = ~(dma_addr_t) 0;
130 return kmalloc(size, mem_flags);
131 }
132
133 for (i = 0; i < HCD_BUFFER_POOLS; i++) {
134 if (size <= pool_max[i])
135 return dma_pool_alloc(hcd->pool[i], mem_flags, dma);
136 }
137 return dma_alloc_coherent(hcd->self.controller, size, dma, mem_flags);
138}
139
140void hcd_buffer_free(
141 struct usb_bus *bus,
142 size_t size,
143 void *addr,
144 dma_addr_t dma
145)
146{
147 struct usb_hcd *hcd = bus_to_hcd(bus);
148 int i;
149
150 if (!addr)
151 return;
152
153 if (!IS_ENABLED(CONFIG_HAS_DMA) ||
154 (!bus->controller->dma_mask &&
155 !(hcd->driver->flags & HCD_LOCAL_MEM))) {
156 kfree(addr);
157 return;
158 }
159
160 for (i = 0; i < HCD_BUFFER_POOLS; i++) {
161 if (size <= pool_max[i]) {
162 dma_pool_free(hcd->pool[i], addr, dma);
163 return;
164 }
165 }
166 dma_free_coherent(hcd->self.controller, size, addr, dma);
167}