LXR linux/arch/arm/mach-mmp/sram.c

   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        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  76        if (res == NULL) {
  77                dev_err(&pdev->dev, "no memory resource defined\n");
  78                ret = -ENODEV;
  79                goto out;
  80        }
  81
  82        if (!resource_size(res))
  83                return 0;
  84
  85        info->sram_phys   = (phys_addr_t)res->start;
  86        info->sram_size   = resource_size(res);
  87        info->sram_virt   = ioremap(info->sram_phys, info->sram_size);
  88        info->pool_name   = kstrdup(pdata->pool_name, GFP_KERNEL);
  89        info->granularity = pdata->granularity;
  90
  91        info->gpool = gen_pool_create(ilog2(info->granularity), -1);
  92        if (!info->gpool) {
  93                dev_err(&pdev->dev, "create pool failed\n");
  94                ret = -ENOMEM;
  95                goto create_pool_err;
  96        }
  97
  98        ret = gen_pool_add_virt(info->gpool, (unsigned long)info->sram_virt,
  99                                info->sram_phys, info->sram_size, -1);
 100        if (ret < 0) {
 101                dev_err(&pdev->dev, "add new chunk failed\n");
 102                ret = -ENOMEM;
 103                goto add_chunk_err;
 104        }
 105
 106        mutex_lock(&sram_lock);
 107        list_add(&info->node, &sram_bank_list);
 108        mutex_unlock(&sram_lock);
 109
 110        platform_set_drvdata(pdev, info);
 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        if (info == NULL)
 131                return -ENODEV;
 132
 133        mutex_lock(&sram_lock);
 134        list_del(&info->node);
 135        mutex_unlock(&sram_lock);
 136
 137        gen_pool_destroy(info->gpool);
 138        iounmap(info->sram_virt);
 139        kfree(info->pool_name);
 140        kfree(info);
 141        return 0;
 142}
 143
 144static const struct platform_device_id sram_id_table[] = {
 145        { "asram", MMP_ASRAM },
 146        { "isram", MMP_ISRAM },
 147        { }
 148};
 149
 150static struct platform_driver sram_driver = {
 151        .probe          = sram_probe,
 152        .remove         = sram_remove,
 153        .driver         = {
 154                .name   = "mmp-sram",
 155        },
 156        .id_table       = sram_id_table,
 157};
 158
 159static int __init sram_init(void)
 160{
 161        return platform_driver_register(&sram_driver);
 162}
 163core_initcall(sram_init);
 164
 165MODULE_LICENSE("GPL");
 166