xref: /kernel/linux/linux-5.10/arch/arm/mach-mmp/sram.c (revision 8c2ecf20) 
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *  linux/arch/arm/mach-mmp/sram.c
4 *
5 *  based on mach-davinci/sram.c - DaVinci simple SRAM allocator
6 *
7 *  Copyright (c) 2011 Marvell Semiconductors Inc.
8 *  All Rights Reserved
9 *
10 *  Add for mmp sram support - Leo Yan <leoy@marvell.com>
11 */
12
13#include <linux/module.h>
14#include <linux/mod_devicetable.h>
15#include <linux/init.h>
16#include <linux/platform_device.h>
17#include <linux/io.h>
18#include <linux/err.h>
19#include <linux/slab.h>
20#include <linux/genalloc.h>
21
22#include <linux/platform_data/dma-mmp_tdma.h>
23
24struct sram_bank_info {
25	char *pool_name;
26	struct gen_pool *gpool;
27	int granularity;
28
29	phys_addr_t sram_phys;
30	void __iomem *sram_virt;
31	u32 sram_size;
32
33	struct list_head node;
34};
35
36static DEFINE_MUTEX(sram_lock);
37static LIST_HEAD(sram_bank_list);
38
39struct gen_pool *sram_get_gpool(char *pool_name)
40{
41	struct sram_bank_info *info = NULL;
42
43	if (!pool_name)
44		return NULL;
45
46	mutex_lock(&sram_lock);
47
48	list_for_each_entry(info, &sram_bank_list, node)
49		if (!strcmp(pool_name, info->pool_name))
50			break;
51
52	mutex_unlock(&sram_lock);
53
54	if (&info->node == &sram_bank_list)
55		return NULL;
56
57	return info->gpool;
58}
59EXPORT_SYMBOL(sram_get_gpool);
60
61static int sram_probe(struct platform_device *pdev)
62{
63	struct sram_platdata *pdata = pdev->dev.platform_data;
64	struct sram_bank_info *info;
65	struct resource *res;
66	int ret = 0;
67
68	if (!pdata || !pdata->pool_name)
69		return -ENODEV;
70
71	info = kzalloc(sizeof(*info), GFP_KERNEL);
72	if (!info)
73		return -ENOMEM;
74
75	platform_set_drvdata(pdev, info);
76
77	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
78	if (res == NULL) {
79		dev_err(&pdev->dev, "no memory resource defined\n");
80		ret = -ENODEV;
81		goto out;
82	}
83
84	if (!resource_size(res))
85		return 0;
86
87	info->sram_phys   = (phys_addr_t)res->start;
88	info->sram_size   = resource_size(res);
89	info->sram_virt   = ioremap(info->sram_phys, info->sram_size);
90	info->pool_name	  = kstrdup(pdata->pool_name, GFP_KERNEL);
91	info->granularity = pdata->granularity;
92
93	info->gpool = gen_pool_create(ilog2(info->granularity), -1);
94	if (!info->gpool) {
95		dev_err(&pdev->dev, "create pool failed\n");
96		ret = -ENOMEM;
97		goto create_pool_err;
98	}
99
100	ret = gen_pool_add_virt(info->gpool, (unsigned long)info->sram_virt,
101				info->sram_phys, info->sram_size, -1);
102	if (ret < 0) {
103		dev_err(&pdev->dev, "add new chunk failed\n");
104		ret = -ENOMEM;
105		goto add_chunk_err;
106	}
107
108	mutex_lock(&sram_lock);
109	list_add(&info->node, &sram_bank_list);
110	mutex_unlock(&sram_lock);
111
112	dev_info(&pdev->dev, "initialized\n");
113	return 0;
114
115add_chunk_err:
116	gen_pool_destroy(info->gpool);
117create_pool_err:
118	iounmap(info->sram_virt);
119	kfree(info->pool_name);
120out:
121	kfree(info);
122	return ret;
123}
124
125static int sram_remove(struct platform_device *pdev)
126{
127	struct sram_bank_info *info;
128
129	info = platform_get_drvdata(pdev);
130
131	if (info->sram_size) {
132		mutex_lock(&sram_lock);
133		list_del(&info->node);
134		mutex_unlock(&sram_lock);
135
136		gen_pool_destroy(info->gpool);
137		iounmap(info->sram_virt);
138		kfree(info->pool_name);
139	}
140
141	kfree(info);
142
143	return 0;
144}
145
146static const struct platform_device_id sram_id_table[] = {
147	{ "asram", MMP_ASRAM },
148	{ "isram", MMP_ISRAM },
149	{ }
150};
151
152static struct platform_driver sram_driver = {
153	.probe		= sram_probe,
154	.remove		= sram_remove,
155	.driver		= {
156		.name	= "mmp-sram",
157	},
158	.id_table	= sram_id_table,
159};
160
161static int __init sram_init(void)
162{
163	return platform_driver_register(&sram_driver);
164}
165core_initcall(sram_init);
166
167MODULE_LICENSE("GPL");
168