1/* 2 * NV-RAM memory access on autcpu12 3 * (C) 2002 Thomas Gleixner (gleixner@autronix.de) 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 * 19 */ 20 21#include <linux/module.h> 22#include <linux/types.h> 23#include <linux/kernel.h> 24#include <linux/ioport.h> 25#include <linux/init.h> 26#include <asm/io.h> 27#include <asm/sizes.h> 28#include <mach/hardware.h> 29#include <mach/autcpu12.h> 30#include <linux/mtd/mtd.h> 31#include <linux/mtd/map.h> 32#include <linux/mtd/partitions.h> 33 34 35static struct mtd_info *sram_mtd; 36 37struct map_info autcpu12_sram_map = { 38 .name = "SRAM", 39 .size = 32768, 40 .bankwidth = 4, 41 .phys = 0x12000000, 42}; 43 44static int __init init_autcpu12_sram (void) 45{ 46 int err, save0, save1; 47 48 autcpu12_sram_map.virt = ioremap(0x12000000, SZ_128K); 49 if (!autcpu12_sram_map.virt) { 50 printk("Failed to ioremap autcpu12 NV-RAM space\n"); 51 err = -EIO; 52 goto out; 53 } 54 simple_map_init(&autcpu_sram_map); 55 56 /* 57 * Check for 32K/128K 58 * read ofs 0 59 * read ofs 0x10000 60 * Write complement to ofs 0x100000 61 * Read and check result on ofs 0x0 62 * Restore contents 63 */ 64 save0 = map_read32(&autcpu12_sram_map,0); 65 save1 = map_read32(&autcpu12_sram_map,0x10000); 66 map_write32(&autcpu12_sram_map,~save0,0x10000); 67 /* if we find this pattern on 0x0, we have 32K size 68 * restore contents and exit 69 */ 70 if ( map_read32(&autcpu12_sram_map,0) != save0) { 71 map_write32(&autcpu12_sram_map,save0,0x0); 72 goto map; 73 } 74 /* We have a 128K found, restore 0x10000 and set size 75 * to 128K 76 */ 77 map_write32(&autcpu12_sram_map,save1,0x10000); 78 autcpu12_sram_map.size = SZ_128K; 79 80map: 81 sram_mtd = do_map_probe("map_ram", &autcpu12_sram_map); 82 if (!sram_mtd) { 83 printk("NV-RAM probe failed\n"); 84 err = -ENXIO; 85 goto out_ioremap; 86 } 87 88 sram_mtd->owner = THIS_MODULE; 89 sram_mtd->erasesize = 16; 90 91 if (add_mtd_device(sram_mtd)) { 92 printk("NV-RAM device addition failed\n"); 93 err = -ENOMEM; 94 goto out_probe; 95 } 96 97 printk("NV-RAM device size %ldKiB registered on AUTCPU12\n",autcpu12_sram_map.size/SZ_1K); 98 99 return 0; 100 101out_probe: 102 map_destroy(sram_mtd); 103 sram_mtd = 0; 104 105out_ioremap: 106 iounmap((void *)autcpu12_sram_map.virt); 107out: 108 return err; 109} 110 111static void __exit cleanup_autcpu12_maps(void) 112{ 113 if (sram_mtd) { 114 del_mtd_device(sram_mtd); 115 map_destroy(sram_mtd); 116 iounmap((void *)autcpu12_sram_map.virt); 117 } 118} 119 120module_init(init_autcpu12_sram); 121module_exit(cleanup_autcpu12_maps); 122 123MODULE_AUTHOR("Thomas Gleixner"); 124MODULE_DESCRIPTION("autcpu12 NV-RAM map driver"); 125MODULE_LICENSE("GPL"); 126