diff options
Diffstat (limited to 'drivers/mtd/maps/sa1100-flash.c')
| -rw-r--r-- | drivers/mtd/maps/sa1100-flash.c | 311 |
1 files changed, 311 insertions, 0 deletions
diff --git a/drivers/mtd/maps/sa1100-flash.c b/drivers/mtd/maps/sa1100-flash.c new file mode 100644 index 0000000000..d3d4e987c1 --- /dev/null +++ b/drivers/mtd/maps/sa1100-flash.c @@ -0,0 +1,311 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Flash memory access on SA11x0 based devices + * + * (C) 2000 Nicolas Pitre <nico@fluxnic.net> + */ +#include <linux/module.h> +#include <linux/types.h> +#include <linux/ioport.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/platform_device.h> +#include <linux/err.h> +#include <linux/io.h> + +#include <linux/mtd/mtd.h> +#include <linux/mtd/map.h> +#include <linux/mtd/partitions.h> +#include <linux/mtd/concat.h> + +#include <mach/hardware.h> +#include <linux/sizes.h> +#include <asm/mach/flash.h> + +struct sa_subdev_info { + char name[16]; + struct map_info map; + struct mtd_info *mtd; + struct flash_platform_data *plat; +}; + +struct sa_info { + struct mtd_info *mtd; + int num_subdev; + struct sa_subdev_info subdev[]; +}; + +static DEFINE_SPINLOCK(sa1100_vpp_lock); +static int sa1100_vpp_refcnt; +static void sa1100_set_vpp(struct map_info *map, int on) +{ + struct sa_subdev_info *subdev = container_of(map, struct sa_subdev_info, map); + unsigned long flags; + + spin_lock_irqsave(&sa1100_vpp_lock, flags); + if (on) { + if (++sa1100_vpp_refcnt == 1) /* first nested 'on' */ + subdev->plat->set_vpp(1); + } else { + if (--sa1100_vpp_refcnt == 0) /* last nested 'off' */ + subdev->plat->set_vpp(0); + } + spin_unlock_irqrestore(&sa1100_vpp_lock, flags); +} + +static void sa1100_destroy_subdev(struct sa_subdev_info *subdev) +{ + if (subdev->mtd) + map_destroy(subdev->mtd); + if (subdev->map.virt) + iounmap(subdev->map.virt); + release_mem_region(subdev->map.phys, subdev->map.size); +} + +static int sa1100_probe_subdev(struct sa_subdev_info *subdev, struct resource *res) +{ + unsigned long phys; + unsigned int size; + int ret; + + phys = res->start; + size = res->end - phys + 1; + + /* + * Retrieve the bankwidth from the MSC registers. + * We currently only implement CS0 and CS1 here. + */ + switch (phys) { + default: + printk(KERN_WARNING "SA1100 flash: unknown base address " + "0x%08lx, assuming CS0\n", phys); + fallthrough; + case SA1100_CS0_PHYS: + subdev->map.bankwidth = (MSC0 & MSC_RBW) ? 2 : 4; + break; + + case SA1100_CS1_PHYS: + subdev->map.bankwidth = ((MSC0 >> 16) & MSC_RBW) ? 2 : 4; + break; + } + + if (!request_mem_region(phys, size, subdev->name)) { + ret = -EBUSY; + goto out; + } + + if (subdev->plat->set_vpp) + subdev->map.set_vpp = sa1100_set_vpp; + + subdev->map.phys = phys; + subdev->map.size = size; + subdev->map.virt = ioremap(phys, size); + if (!subdev->map.virt) { + ret = -ENOMEM; + goto err; + } + + simple_map_init(&subdev->map); + + /* + * Now let's probe for the actual flash. Do it here since + * specific machine settings might have been set above. + */ + subdev->mtd = do_map_probe(subdev->plat->map_name, &subdev->map); + if (subdev->mtd == NULL) { + ret = -ENXIO; + goto err; + } + + printk(KERN_INFO "SA1100 flash: CFI device at 0x%08lx, %uMiB, %d-bit\n", + phys, (unsigned)(subdev->mtd->size >> 20), + subdev->map.bankwidth * 8); + + return 0; + + err: + sa1100_destroy_subdev(subdev); + out: + return ret; +} + +static void sa1100_destroy(struct sa_info *info, struct flash_platform_data *plat) +{ + int i; + + if (info->mtd) { + mtd_device_unregister(info->mtd); + if (info->mtd != info->subdev[0].mtd) + mtd_concat_destroy(info->mtd); + } + + for (i = info->num_subdev - 1; i >= 0; i--) + sa1100_destroy_subdev(&info->subdev[i]); + kfree(info); + + if (plat->exit) + plat->exit(); +} + +static struct sa_info *sa1100_setup_mtd(struct platform_device *pdev, + struct flash_platform_data *plat) +{ + struct sa_info *info; + int nr, size, i, ret = 0; + + /* + * Count number of devices. + */ + for (nr = 0; ; nr++) + if (!platform_get_resource(pdev, IORESOURCE_MEM, nr)) + break; + + if (nr == 0) { + ret = -ENODEV; + goto out; + } + + size = sizeof(struct sa_info) + sizeof(struct sa_subdev_info) * nr; + + /* + * Allocate the map_info structs in one go. + */ + info = kzalloc(size, GFP_KERNEL); + if (!info) { + ret = -ENOMEM; + goto out; + } + + if (plat->init) { + ret = plat->init(); + if (ret) + goto err; + } + + /* + * Claim and then map the memory regions. + */ + for (i = 0; i < nr; i++) { + struct sa_subdev_info *subdev = &info->subdev[i]; + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, i); + if (!res) + break; + + subdev->map.name = subdev->name; + sprintf(subdev->name, "%s-%d", plat->name, i); + subdev->plat = plat; + + ret = sa1100_probe_subdev(subdev, res); + if (ret) + break; + } + + info->num_subdev = i; + + /* + * ENXIO is special. It means we didn't find a chip when we probed. + */ + if (ret != 0 && !(ret == -ENXIO && info->num_subdev > 0)) + goto err; + + /* + * If we found one device, don't bother with concat support. If + * we found multiple devices, use concat if we have it available, + * otherwise fail. Either way, it'll be called "sa1100". + */ + if (info->num_subdev == 1) { + strcpy(info->subdev[0].name, plat->name); + info->mtd = info->subdev[0].mtd; + ret = 0; + } else if (info->num_subdev > 1) { + struct mtd_info **cdev; + + cdev = kmalloc_array(nr, sizeof(*cdev), GFP_KERNEL); + if (!cdev) { + ret = -ENOMEM; + goto err; + } + + /* + * We detected multiple devices. Concatenate them together. + */ + for (i = 0; i < info->num_subdev; i++) + cdev[i] = info->subdev[i].mtd; + + info->mtd = mtd_concat_create(cdev, info->num_subdev, + plat->name); + kfree(cdev); + if (info->mtd == NULL) { + ret = -ENXIO; + goto err; + } + } + info->mtd->dev.parent = &pdev->dev; + + if (ret == 0) + return info; + + err: + sa1100_destroy(info, plat); + out: + return ERR_PTR(ret); +} + +static const char * const part_probes[] = { "cmdlinepart", "RedBoot", NULL }; + +static int sa1100_mtd_probe(struct platform_device *pdev) +{ + struct flash_platform_data *plat = dev_get_platdata(&pdev->dev); + struct sa_info *info; + int err; + + if (!plat) + return -ENODEV; + + info = sa1100_setup_mtd(pdev, plat); + if (IS_ERR(info)) { + err = PTR_ERR(info); + goto out; + } + + /* + * Partition selection stuff. + */ + mtd_device_parse_register(info->mtd, part_probes, NULL, plat->parts, + plat->nr_parts); + + platform_set_drvdata(pdev, info); + err = 0; + + out: + return err; +} + +static int sa1100_mtd_remove(struct platform_device *pdev) +{ + struct sa_info *info = platform_get_drvdata(pdev); + struct flash_platform_data *plat = dev_get_platdata(&pdev->dev); + + sa1100_destroy(info, plat); + + return 0; +} + +static struct platform_driver sa1100_mtd_driver = { + .probe = sa1100_mtd_probe, + .remove = sa1100_mtd_remove, + .driver = { + .name = "sa1100-mtd", + }, +}; + +module_platform_driver(sa1100_mtd_driver); + +MODULE_AUTHOR("Nicolas Pitre"); +MODULE_DESCRIPTION("SA1100 CFI map driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:sa1100-mtd"); |