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/mod_devicetable.h>
19 #include <linux/init.h>
20 #include <linux/platform_device.h>
21 #include <linux/io.h>
22 #include <linux/err.h>
23 #include <linux/slab.h>
24 #include <linux/genalloc.h>
25
26 #include <linux/platform_data/dma-mmp_tdma.h>
27
28 struct sram_bank_info {
29 char *pool_name;
30 struct gen_pool *gpool;
31 int granularity;
32
33 phys_addr_t sram_phys;
34 void __iomem *sram_virt;
35 u32 sram_size;
36
37 struct list_head node;
38 };
39
40 static DEFINE_MUTEX(sram_lock);
41 static LIST_HEAD(sram_bank_list);
42
sram_get_gpool(char * pool_name)43 struct gen_pool *sram_get_gpool(char *pool_name)
44 {
45 struct sram_bank_info *info = NULL;
46
47 if (!pool_name)
48 return NULL;
49
50 mutex_lock(&sram_lock);
51
52 list_for_each_entry(info, &sram_bank_list, node)
53 if (!strcmp(pool_name, info->pool_name))
54 break;
55
56 mutex_unlock(&sram_lock);
57
58 if (&info->node == &sram_bank_list)
59 return NULL;
60
61 return info->gpool;
62 }
63 EXPORT_SYMBOL(sram_get_gpool);
64
sram_probe(struct platform_device * pdev)65 static int sram_probe(struct platform_device *pdev)
66 {
67 struct sram_platdata *pdata = pdev->dev.platform_data;
68 struct sram_bank_info *info;
69 struct resource *res;
70 int ret = 0;
71
72 if (!pdata || !pdata->pool_name)
73 return -ENODEV;
74
75 info = kzalloc(sizeof(*info), GFP_KERNEL);
76 if (!info)
77 return -ENOMEM;
78
79 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
80 if (res == NULL) {
81 dev_err(&pdev->dev, "no memory resource defined\n");
82 ret = -ENODEV;
83 goto out;
84 }
85
86 if (!resource_size(res))
87 return 0;
88
89 info->sram_phys = (phys_addr_t)res->start;
90 info->sram_size = resource_size(res);
91 info->sram_virt = ioremap(info->sram_phys, info->sram_size);
92 info->pool_name = kstrdup(pdata->pool_name, GFP_KERNEL);
93 info->granularity = pdata->granularity;
94
95 info->gpool = gen_pool_create(ilog2(info->granularity), -1);
96 if (!info->gpool) {
97 dev_err(&pdev->dev, "create pool failed\n");
98 ret = -ENOMEM;
99 goto create_pool_err;
100 }
101
102 ret = gen_pool_add_virt(info->gpool, (unsigned long)info->sram_virt,
103 info->sram_phys, info->sram_size, -1);
104 if (ret < 0) {
105 dev_err(&pdev->dev, "add new chunk failed\n");
106 ret = -ENOMEM;
107 goto add_chunk_err;
108 }
109
110 mutex_lock(&sram_lock);
111 list_add(&info->node, &sram_bank_list);
112 mutex_unlock(&sram_lock);
113
114 platform_set_drvdata(pdev, info);
115
116 dev_info(&pdev->dev, "initialized\n");
117 return 0;
118
119 add_chunk_err:
120 gen_pool_destroy(info->gpool);
121 create_pool_err:
122 iounmap(info->sram_virt);
123 kfree(info->pool_name);
124 out:
125 kfree(info);
126 return ret;
127 }
128
sram_remove(struct platform_device * pdev)129 static int sram_remove(struct platform_device *pdev)
130 {
131 struct sram_bank_info *info;
132
133 info = platform_get_drvdata(pdev);
134 if (info == NULL)
135 return -ENODEV;
136
137 mutex_lock(&sram_lock);
138 list_del(&info->node);
139 mutex_unlock(&sram_lock);
140
141 gen_pool_destroy(info->gpool);
142 iounmap(info->sram_virt);
143 kfree(info->pool_name);
144 kfree(info);
145 return 0;
146 }
147
148 static const struct platform_device_id sram_id_table[] = {
149 { "asram", MMP_ASRAM },
150 { "isram", MMP_ISRAM },
151 { }
152 };
153
154 static struct platform_driver sram_driver = {
155 .probe = sram_probe,
156 .remove = sram_remove,
157 .driver = {
158 .name = "mmp-sram",
159 },
160 .id_table = sram_id_table,
161 };
162
sram_init(void)163 static int __init sram_init(void)
164 {
165 return platform_driver_register(&sram_driver);
166 }
167 core_initcall(sram_init);
168
169 MODULE_LICENSE("GPL");
170
