1 /*
2 * linux/arch/arm/mach-mmp/sram.c
3 *
4 * based on mach-davinci/sram.c - DaVinci simple SRAM allocator
5 *
6 * Copyright (c) 2011 Marvell Semiconductors Inc.
7 * All Rights Reserved
8 *
9 * Add for mmp sram support - Leo Yan <leoy@marvell.com>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
14 *
15 */
16
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/platform_device.h>
20 #include <linux/io.h>
21 #include <linux/err.h>
22 #include <linux/slab.h>
23 #include <linux/genalloc.h>
24
25 #include <linux/platform_data/dma-mmp_tdma.h>
26
27 struct sram_bank_info {
28 char *pool_name;
29 struct gen_pool *gpool;
30 int granularity;
31
32 phys_addr_t sram_phys;
33 void __iomem *sram_virt;
34 u32 sram_size;
35
36 struct list_head node;
37 };
38
39 static DEFINE_MUTEX(sram_lock);
40 static LIST_HEAD(sram_bank_list);
41
sram_get_gpool(char * pool_name)42 struct gen_pool *sram_get_gpool(char *pool_name)
43 {
44 struct sram_bank_info *info = NULL;
45
46 if (!pool_name)
47 return NULL;
48
49 mutex_lock(&sram_lock);
50
51 list_for_each_entry(info, &sram_bank_list, node)
52 if (!strcmp(pool_name, info->pool_name))
53 break;
54
55 mutex_unlock(&sram_lock);
56
57 if (&info->node == &sram_bank_list)
58 return NULL;
59
60 return info->gpool;
61 }
62 EXPORT_SYMBOL(sram_get_gpool);
63
sram_probe(struct platform_device * pdev)64 static int sram_probe(struct platform_device *pdev)
65 {
66 struct sram_platdata *pdata = pdev->dev.platform_data;
67 struct sram_bank_info *info;
68 struct resource *res;
69 int ret = 0;
70
71 if (!pdata || !pdata->pool_name)
72 return -ENODEV;
73
74 info = kzalloc(sizeof(*info), GFP_KERNEL);
75 if (!info)
76 return -ENOMEM;
77
78 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
79 if (res == NULL) {
80 dev_err(&pdev->dev, "no memory resource defined\n");
81 ret = -ENODEV;
82 goto out;
83 }
84
85 if (!resource_size(res))
86 return 0;
87
88 info->sram_phys = (phys_addr_t)res->start;
89 info->sram_size = resource_size(res);
90 info->sram_virt = ioremap(info->sram_phys, info->sram_size);
91 info->pool_name = kstrdup(pdata->pool_name, GFP_KERNEL);
92 info->granularity = pdata->granularity;
93
94 info->gpool = gen_pool_create(ilog2(info->granularity), -1);
95 if (!info->gpool) {
96 dev_err(&pdev->dev, "create pool failed\n");
97 ret = -ENOMEM;
98 goto create_pool_err;
99 }
100
101 ret = gen_pool_add_virt(info->gpool, (unsigned long)info->sram_virt,
102 info->sram_phys, info->sram_size, -1);
103 if (ret < 0) {
104 dev_err(&pdev->dev, "add new chunk failed\n");
105 ret = -ENOMEM;
106 goto add_chunk_err;
107 }
108
109 mutex_lock(&sram_lock);
110 list_add(&info->node, &sram_bank_list);
111 mutex_unlock(&sram_lock);
112
113 platform_set_drvdata(pdev, info);
114
115 dev_info(&pdev->dev, "initialized\n");
116 return 0;
117
118 add_chunk_err:
119 gen_pool_destroy(info->gpool);
120 create_pool_err:
121 iounmap(info->sram_virt);
122 kfree(info->pool_name);
123 out:
124 kfree(info);
125 return ret;
126 }
127
sram_remove(struct platform_device * pdev)128 static int sram_remove(struct platform_device *pdev)
129 {
130 struct sram_bank_info *info;
131
132 info = platform_get_drvdata(pdev);
133 if (info == NULL)
134 return -ENODEV;
135
136 mutex_lock(&sram_lock);
137 list_del(&info->node);
138 mutex_unlock(&sram_lock);
139
140 gen_pool_destroy(info->gpool);
141 iounmap(info->sram_virt);
142 kfree(info->pool_name);
143 kfree(info);
144 return 0;
145 }
146
147 static const struct platform_device_id sram_id_table[] = {
148 { "asram", MMP_ASRAM },
149 { "isram", MMP_ISRAM },
150 { }
151 };
152
153 static struct platform_driver sram_driver = {
154 .probe = sram_probe,
155 .remove = sram_remove,
156 .driver = {
157 .name = "mmp-sram",
158 },
159 .id_table = sram_id_table,
160 };
161
sram_init(void)162 static int __init sram_init(void)
163 {
164 return platform_driver_register(&sram_driver);
165 }
166 core_initcall(sram_init);
167
168 MODULE_LICENSE("GPL");
169