/* * Flash mappings described by the OF (or flattened) device tree * * Copyright (C) 2006 MontaVista Software Inc. * Author: Vitaly Wool <vwool@ru.mvista.com> * * Revised to handle newer style flash binding by: *   Copyright (C) 2007 David Gibson, IBM Corporation. * * This program is free software; you can redistribute  it and/or modify it * under  the terms of  the GNU General  Public License as published by the * Free Software Foundation;  either version 2 of the  License, or (at your * option) any later version. */ #include <linux/module.h>#include <linux/types.h>#include <linux/init.h>#include <linux/device.h>#include <linux/mtd/mtd.h>#include <linux/mtd/map.h>#include <linux/mtd/partitions.h>#include <linux/mtd/concat.h>#include <linux/of.h>#include <linux/of_address.h>#include <linux/of_platform.h>#include <linux/slab.h> struct of_flash_list {	struct mtd_info *mtd;	struct map_info map;	struct resource *res;}; struct of_flash {	struct mtd_info		*cmtd;	int list_size; /* number of elements in of_flash_list */	struct of_flash_list	list[0];}; static int of_flash_remove(struct platform_device *dev){	struct of_flash *info;	int i; 	info = dev_get_drvdata(&dev->dev);	if (!info)		return 0;	dev_set_drvdata(&dev->dev, NULL); 	if (info->cmtd != info->list[0].mtd) {		mtd_device_unregister(info->cmtd);		mtd_concat_destroy(info->cmtd);	} 	if (info->cmtd)		mtd_device_unregister(info->cmtd); 	for (i = 0; i < info->list_size; i++) {		if (info->list[i].mtd)			map_destroy(info->list[i].mtd); 		if (info->list[i].map.virt)			iounmap(info->list[i].map.virt); 		if (info->list[i].res) {			release_resource(info->list[i].res);			kfree(info->list[i].res);		}	}	return 0;} static const char * const rom_probe_types[] = {	"cfi_probe", "jedec_probe", "map_rom" }; /* Helper function to handle probing of the obsolete "direct-mapped" * compatible binding, which has an extra "probe-type" property * describing the type of flash probe necessary. */static struct mtd_info *obsolete_probe(struct platform_device *dev,				       struct map_info *map){	struct device_node *dp = dev->dev.of_node;	const char *of_probe;	struct mtd_info *mtd;	int i; 	dev_warn(&dev->dev, "Device tree uses obsolete \"direct-mapped\" "		 "flash binding\n"); 	of_probe = of_get_property(dp, "probe-type", NULL);	if (!of_probe) {		for (i = 0; i < ARRAY_SIZE(rom_probe_types); i++) {			mtd = do_map_probe(rom_probe_types[i], map);			if (mtd)				return mtd;		}		return NULL;	} else if (strcmp(of_probe, "CFI") == 0) {		return do_map_probe("cfi_probe", map);	} else if (strcmp(of_probe, "JEDEC") == 0) {		return do_map_probe("jedec_probe", map);	} else {		if (strcmp(of_probe, "ROM") != 0)			dev_warn(&dev->dev, "obsolete_probe: don't know probe "				 "type '%s', mapping as rom\n", of_probe);		return do_map_probe("mtd_rom", map);	}} /* When partitions are set we look for a linux,part-probe property which   specifies the list of partition probers to use. If none is given then the   default is use. These take precedence over other device tree   information. */static const char * const part_probe_types_def[] = {	"cmdlinepart", "RedBoot", "ofpart", "ofoldpart", NULL }; static const char * const *of_get_probes(struct device_node *dp){	const char *cp;	int cplen;	unsigned int l;	unsigned int count;	const char **res; 	cp = of_get_property(dp, "linux,part-probe", &cplen);	if (cp == NULL)		return part_probe_types_def; 	count = 0;	for (l = 0; l != cplen; l++)		if (cp[l] == 0)			count++; 	res = kzalloc((count + 1)*sizeof(*res), GFP_KERNEL);	count = 0;	while (cplen > 0) {		res[count] = cp;		l = strlen(cp) + 1;		cp += l;		cplen -= l;		count++;	}	return res;} static void of_free_probes(const char * const *probes){	if (probes != part_probe_types_def)		kfree(probes);} static struct of_device_id of_flash_match[];static int of_flash_probe(struct platform_device *dev){	const char * const *part_probe_types;	const struct of_device_id *match;	struct device_node *dp = dev->dev.of_node;	struct resource res;	struct of_flash *info;	const char *probe_type;	const __be32 *width;	int err;	int i;	int count;	const __be32 *p;	int reg_tuple_size;	struct mtd_info **mtd_list = NULL;	resource_size_t res_size;	struct mtd_part_parser_data ppdata;	bool map_indirect;	const char *mtd_name = NULL; 	match = of_match_device(of_flash_match, &dev->dev);	if (!match)		return -EINVAL;	probe_type = match->data; 	reg_tuple_size = (of_n_addr_cells(dp) + of_n_size_cells(dp)) * sizeof(u32); 	of_property_read_string(dp, "linux,mtd-name", &mtd_name); 	/*	 * Get number of "reg" tuples. Scan for MTD devices on area's	 * described by each "reg" region. This makes it possible (including	 * the concat support) to support the Intel P30 48F4400 chips which	 * consists internally of 2 non-identical NOR chips on one die.	 */	p = of_get_property(dp, "reg", &count);	if (count % reg_tuple_size != 0) {		dev_err(&dev->dev, "Malformed reg property on %s\n",				dev->dev.of_node->full_name);		err = -EINVAL;		goto err_flash_remove;	}	count /= reg_tuple_size; 	map_indirect = of_property_read_bool(dp, "no-unaligned-direct-access"); 	err = -ENOMEM;	info = devm_kzalloc(&dev->dev,			    sizeof(struct of_flash) +			    sizeof(struct of_flash_list) * count, GFP_KERNEL);	if (!info)		goto err_flash_remove; 	dev_set_drvdata(&dev->dev, info); 	mtd_list = kzalloc(sizeof(*mtd_list) * count, GFP_KERNEL);	if (!mtd_list)		goto err_flash_remove; 	for (i = 0; i < count; i++) {		err = -ENXIO;		if (of_address_to_resource(dp, i, &res)) {			/*			 * Continue with next register tuple if this			 * one is not mappable			 */			continue;		} 		dev_dbg(&dev->dev, "of_flash device: %pR\n", &res); 		err = -EBUSY;		res_size = resource_size(&res);		info->list[i].res = request_mem_region(res.start, res_size,						       dev_name(&dev->dev));		if (!info->list[i].res)			goto err_out; 		err = -ENXIO;		width = of_get_property(dp, "bank-width", NULL);		if (!width) {			dev_err(&dev->dev, "Can't get bank width from device"				" tree\n");			goto err_out;		} 		info->list[i].map.name = mtd_name ?: dev_name(&dev->dev);		info->list[i].map.phys = res.start;		info->list[i].map.size = res_size;		info->list[i].map.bankwidth = be32_to_cpup(width);		info->list[i].map.device_node = dp; 		err = -ENOMEM;		info->list[i].map.virt = ioremap(info->list[i].map.phys,						 info->list[i].map.size);		if (!info->list[i].map.virt) {			dev_err(&dev->dev, "Failed to ioremap() flash"				" region\n");			goto err_out;		} 		simple_map_init(&info->list[i].map); 		/*		 * On some platforms (e.g. MPC5200) a direct 1:1 mapping		 * may cause problems with JFFS2 usage, as the local bus (LPB)		 * doesn't support unaligned accesses as implemented in the		 * JFFS2 code via memcpy(). By setting NO_XIP, the		 * flash will not be exposed directly to the MTD users		 * (e.g. JFFS2) any more.		 */		if (map_indirect)			info->list[i].map.phys = NO_XIP; 		if (probe_type) {			info->list[i].mtd = do_map_probe(probe_type,							 &info->list[i].map);		} else {			info->list[i].mtd = obsolete_probe(dev,							   &info->list[i].map);		}		mtd_list[i] = info->list[i].mtd; 		err = -ENXIO;		if (!info->list[i].mtd) {			dev_err(&dev->dev, "do_map_probe() failed\n");			goto err_out;		} else {			info->list_size++;		}		info->list[i].mtd->owner = THIS_MODULE;		info->list[i].mtd->dev.parent = &dev->dev;	} 	err = 0;	info->cmtd = NULL;	if (info->list_size == 1) {		info->cmtd = info->list[0].mtd;	} else if (info->list_size > 1) {		/*		 * We detected multiple devices. Concatenate them together.		 */		info->cmtd = mtd_concat_create(mtd_list, info->list_size,					       dev_name(&dev->dev));	}	if (info->cmtd == NULL)		err = -ENXIO; 	if (err)		goto err_out; 	ppdata.of_node = dp;	part_probe_types = of_get_probes(dp);	mtd_device_parse_register(info->cmtd, part_probe_types, &ppdata,			NULL, 0);	of_free_probes(part_probe_types); 	kfree(mtd_list); 	return 0; err_out:	kfree(mtd_list);err_flash_remove:	of_flash_remove(dev); 	return err;} static struct of_device_id of_flash_match[] = {	{		.compatible	= "cfi-flash",		.data		= (void *)"cfi_probe",	},	{		/* FIXME: JEDEC chips can't be safely and reliably		 * probed, although the mtd code gets it right in		 * practice most of the time.  We should use the		 * vendor and device ids specified by the binding to		 * bypass the heuristic probe code, but the mtd layer		 * provides, at present, no interface for doing so		 * :(. */		.compatible	= "jedec-flash",		.data		= (void *)"jedec_probe",	},	{		.compatible     = "mtd-ram",		.data           = (void *)"map_ram",	},	{		.type		= "rom",		.compatible	= "direct-mapped"	},	{ },};MODULE_DEVICE_TABLE(of, of_flash_match); static struct platform_driver of_flash_driver = {	.driver = {		.name = "of-flash",		.owner = THIS_MODULE,		.of_match_table = of_flash_match,	},	.probe		= of_flash_probe,	.remove		= of_flash_remove,}; module_platform_driver(of_flash_driver); MODULE_LICENSE("GPL");MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");MODULE_DESCRIPTION("Device tree based MTD map driver");