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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Flash memory access on SA11x0 based devices4 *5 * (C) 2000 Nicolas Pitre <nico@fluxnic.net>6 */7#include <linux/module.h>8#include <linux/types.h>9#include <linux/ioport.h>10#include <linux/kernel.h>11#include <linux/init.h>12#include <linux/errno.h>13#include <linux/slab.h>14#include <linux/platform_device.h>15#include <linux/err.h>16#include <linux/io.h>17 18#include <linux/mtd/mtd.h>19#include <linux/mtd/map.h>20#include <linux/mtd/partitions.h>21#include <linux/mtd/concat.h>22 23#include <mach/hardware.h>24#include <linux/sizes.h>25#include <asm/mach/flash.h>26 27struct sa_subdev_info {28 char name[16];29 struct map_info map;30 struct mtd_info *mtd;31 struct flash_platform_data *plat;32};33 34struct sa_info {35 struct mtd_info *mtd;36 int num_subdev;37 struct sa_subdev_info subdev[];38};39 40static DEFINE_SPINLOCK(sa1100_vpp_lock);41static int sa1100_vpp_refcnt;42static void sa1100_set_vpp(struct map_info *map, int on)43{44 struct sa_subdev_info *subdev = container_of(map, struct sa_subdev_info, map);45 unsigned long flags;46 47 spin_lock_irqsave(&sa1100_vpp_lock, flags);48 if (on) {49 if (++sa1100_vpp_refcnt == 1) /* first nested 'on' */50 subdev->plat->set_vpp(1);51 } else {52 if (--sa1100_vpp_refcnt == 0) /* last nested 'off' */53 subdev->plat->set_vpp(0);54 }55 spin_unlock_irqrestore(&sa1100_vpp_lock, flags);56}57 58static void sa1100_destroy_subdev(struct sa_subdev_info *subdev)59{60 if (subdev->mtd)61 map_destroy(subdev->mtd);62 if (subdev->map.virt)63 iounmap(subdev->map.virt);64 release_mem_region(subdev->map.phys, subdev->map.size);65}66 67static int sa1100_probe_subdev(struct sa_subdev_info *subdev, struct resource *res)68{69 unsigned long phys;70 unsigned int size;71 int ret;72 73 phys = res->start;74 size = res->end - phys + 1;75 76 /*77 * Retrieve the bankwidth from the MSC registers.78 * We currently only implement CS0 and CS1 here.79 */80 switch (phys) {81 default:82 printk(KERN_WARNING "SA1100 flash: unknown base address "83 "0x%08lx, assuming CS0\n", phys);84 fallthrough;85 case SA1100_CS0_PHYS:86 subdev->map.bankwidth = (MSC0 & MSC_RBW) ? 2 : 4;87 break;88 89 case SA1100_CS1_PHYS:90 subdev->map.bankwidth = ((MSC0 >> 16) & MSC_RBW) ? 2 : 4;91 break;92 }93 94 if (!request_mem_region(phys, size, subdev->name)) {95 ret = -EBUSY;96 goto out;97 }98 99 if (subdev->plat->set_vpp)100 subdev->map.set_vpp = sa1100_set_vpp;101 102 subdev->map.phys = phys;103 subdev->map.size = size;104 subdev->map.virt = ioremap(phys, size);105 if (!subdev->map.virt) {106 ret = -ENOMEM;107 goto err;108 }109 110 simple_map_init(&subdev->map);111 112 /*113 * Now let's probe for the actual flash. Do it here since114 * specific machine settings might have been set above.115 */116 subdev->mtd = do_map_probe(subdev->plat->map_name, &subdev->map);117 if (subdev->mtd == NULL) {118 ret = -ENXIO;119 goto err;120 }121 122 printk(KERN_INFO "SA1100 flash: CFI device at 0x%08lx, %uMiB, %d-bit\n",123 phys, (unsigned)(subdev->mtd->size >> 20),124 subdev->map.bankwidth * 8);125 126 return 0;127 128 err:129 sa1100_destroy_subdev(subdev);130 out:131 return ret;132}133 134static void sa1100_destroy(struct sa_info *info, struct flash_platform_data *plat)135{136 int i;137 138 if (info->mtd) {139 mtd_device_unregister(info->mtd);140 if (info->mtd != info->subdev[0].mtd)141 mtd_concat_destroy(info->mtd);142 }143 144 for (i = info->num_subdev - 1; i >= 0; i--)145 sa1100_destroy_subdev(&info->subdev[i]);146 kfree(info);147 148 if (plat->exit)149 plat->exit();150}151 152static struct sa_info *sa1100_setup_mtd(struct platform_device *pdev,153 struct flash_platform_data *plat)154{155 struct sa_info *info;156 int nr, i, ret = 0;157 158 /*159 * Count number of devices.160 */161 for (nr = 0; ; nr++)162 if (!platform_get_resource(pdev, IORESOURCE_MEM, nr))163 break;164 165 if (nr == 0) {166 ret = -ENODEV;167 goto out;168 }169 170 /*171 * Allocate the map_info structs in one go.172 */173 info = kzalloc(struct_size(info, subdev, nr), GFP_KERNEL);174 if (!info) {175 ret = -ENOMEM;176 goto out;177 }178 179 if (plat->init) {180 ret = plat->init();181 if (ret)182 goto err;183 }184 185 /*186 * Claim and then map the memory regions.187 */188 for (i = 0; i < nr; i++) {189 struct sa_subdev_info *subdev = &info->subdev[i];190 struct resource *res;191 192 res = platform_get_resource(pdev, IORESOURCE_MEM, i);193 if (!res)194 break;195 196 subdev->map.name = subdev->name;197 sprintf(subdev->name, "%s-%d", plat->name, i);198 subdev->plat = plat;199 200 ret = sa1100_probe_subdev(subdev, res);201 if (ret)202 break;203 }204 205 info->num_subdev = i;206 207 /*208 * ENXIO is special. It means we didn't find a chip when we probed.209 */210 if (ret != 0 && !(ret == -ENXIO && info->num_subdev > 0))211 goto err;212 213 /*214 * If we found one device, don't bother with concat support. If215 * we found multiple devices, use concat if we have it available,216 * otherwise fail. Either way, it'll be called "sa1100".217 */218 if (info->num_subdev == 1) {219 strcpy(info->subdev[0].name, plat->name);220 info->mtd = info->subdev[0].mtd;221 ret = 0;222 } else if (info->num_subdev > 1) {223 struct mtd_info **cdev;224 225 cdev = kmalloc_array(nr, sizeof(*cdev), GFP_KERNEL);226 if (!cdev) {227 ret = -ENOMEM;228 goto err;229 }230 231 /*232 * We detected multiple devices. Concatenate them together.233 */234 for (i = 0; i < info->num_subdev; i++)235 cdev[i] = info->subdev[i].mtd;236 237 info->mtd = mtd_concat_create(cdev, info->num_subdev,238 plat->name);239 kfree(cdev);240 if (info->mtd == NULL) {241 ret = -ENXIO;242 goto err;243 }244 }245 info->mtd->dev.parent = &pdev->dev;246 247 if (ret == 0)248 return info;249 250 err:251 sa1100_destroy(info, plat);252 out:253 return ERR_PTR(ret);254}255 256static const char * const part_probes[] = { "cmdlinepart", "RedBoot", NULL };257 258static int sa1100_mtd_probe(struct platform_device *pdev)259{260 struct flash_platform_data *plat = dev_get_platdata(&pdev->dev);261 struct sa_info *info;262 int err;263 264 if (!plat)265 return -ENODEV;266 267 info = sa1100_setup_mtd(pdev, plat);268 if (IS_ERR(info)) {269 err = PTR_ERR(info);270 goto out;271 }272 273 /*274 * Partition selection stuff.275 */276 mtd_device_parse_register(info->mtd, part_probes, NULL, plat->parts,277 plat->nr_parts);278 279 platform_set_drvdata(pdev, info);280 err = 0;281 282 out:283 return err;284}285 286static void sa1100_mtd_remove(struct platform_device *pdev)287{288 struct sa_info *info = platform_get_drvdata(pdev);289 struct flash_platform_data *plat = dev_get_platdata(&pdev->dev);290 291 sa1100_destroy(info, plat);292}293 294static struct platform_driver sa1100_mtd_driver = {295 .probe = sa1100_mtd_probe,296 .remove_new = sa1100_mtd_remove,297 .driver = {298 .name = "sa1100-mtd",299 },300};301 302module_platform_driver(sa1100_mtd_driver);303 304MODULE_AUTHOR("Nicolas Pitre");305MODULE_DESCRIPTION("SA1100 CFI map driver");306MODULE_LICENSE("GPL");307MODULE_ALIAS("platform:sa1100-mtd");308