source: trunk/target/linux/lantiq/patches-2.6.39/0004-MIPS-Lantiq-Add-NOR-flash-support.patch @ 27104

Last change on this file since 27104 was 27104, checked in by florian, 5 years ago

[kernel] update to 2.6.39.1

patch from Peter Wagner

File size: 8.3 KB
  • drivers/mtd/maps/Kconfig

    From cd0d53b24ca744295d2cdf69bb2b659571091b75 Mon Sep 17 00:00:00 2001
    From: John Crispin <blogic@openwrt.org>
    Date: Tue, 12 Apr 2011 18:10:01 +0200
    Subject: [PATCH 04/13] MIPS: Lantiq: Add NOR flash support
    
    This patch adds the driver/map for NOR devices attached to the SoC via the
    External Bus Unit (EBU).
    
    Signed-off-by: John Crispin <blogic@openwrt.org>
    Signed-off-by: Ralph Hempel <ralph.hempel@lantiq.com>
    Cc: David Woodhouse <dwmw2@infradead.org>
    Cc: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
    Cc: linux-mips@linux-mips.org
    Cc: linux-mtd@lists.infradead.org
    Acked-by: Artem Bityutskiy <dedekind1@gmail.com>
    Patchwork: https://patchwork.linux-mips.org/patch/2285/
    Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
    ---
     drivers/mtd/maps/Kconfig        |    7 +
     drivers/mtd/maps/Makefile       |    1 +
     drivers/mtd/maps/lantiq-flash.c |  251 +++++++++++++++++++++++++++++++++++++++
     3 files changed, 259 insertions(+), 0 deletions(-)
     create mode 100644 drivers/mtd/maps/lantiq-flash.c
    
    a b config MTD_BCM963XX 
    260260          Support for parsing CFE image tag and creating MTD partitions on 
    261261          Broadcom BCM63xx boards. 
    262262 
     263config MTD_LANTIQ 
     264        tristate "Lantiq SoC NOR support" 
     265        depends on LANTIQ 
     266        select MTD_PARTITIONS 
     267        help 
     268          Support for NOR flash attached to the Lantiq SoC's External Bus Unit. 
     269 
    263270config MTD_DILNETPC 
    264271        tristate "CFI Flash device mapped on DIL/Net PC" 
    265272        depends on X86 && MTD_PARTITIONS && MTD_CFI_INTELEXT && BROKEN 
  • drivers/mtd/maps/Makefile

    a b obj-$(CONFIG_MTD_VMU) += vmu-flash.o 
    6060obj-$(CONFIG_MTD_GPIO_ADDR)     += gpio-addr-flash.o 
    6161obj-$(CONFIG_MTD_BCM963XX)      += bcm963xx-flash.o 
    6262obj-$(CONFIG_MTD_LATCH_ADDR)    += latch-addr-flash.o 
     63obj-$(CONFIG_MTD_LANTIQ)        += lantiq-flash.o 
  • new file drivers/mtd/maps/lantiq-flash.c

    - +  
     1/* 
     2 *  This program is free software; you can redistribute it and/or modify it 
     3 *  under the terms of the GNU General Public License version 2 as published 
     4 *  by the Free Software Foundation. 
     5 * 
     6 *  Copyright (C) 2004 Liu Peng Infineon IFAP DC COM CPE 
     7 *  Copyright (C) 2010 John Crispin <blogic@openwrt.org> 
     8 */ 
     9 
     10#include <linux/module.h> 
     11#include <linux/types.h> 
     12#include <linux/kernel.h> 
     13#include <linux/io.h> 
     14#include <linux/slab.h> 
     15#include <linux/init.h> 
     16#include <linux/mtd/mtd.h> 
     17#include <linux/mtd/map.h> 
     18#include <linux/mtd/partitions.h> 
     19#include <linux/mtd/cfi.h> 
     20#include <linux/platform_device.h> 
     21#include <linux/mtd/physmap.h> 
     22 
     23#include <lantiq_soc.h> 
     24#include <lantiq_platform.h> 
     25 
     26/* 
     27 * The NOR flash is connected to the same external bus unit (EBU) as PCI. 
     28 * To make PCI work we need to enable the endianness swapping for the address 
     29 * written to the EBU. This endianness swapping works for PCI correctly but 
     30 * fails for attached NOR devices. To workaround this we need to use a complex 
     31 * map. The workaround involves swapping all addresses whilst probing the chip. 
     32 * Once probing is complete we stop swapping the addresses but swizzle the 
     33 * unlock addresses to ensure that access to the NOR device works correctly. 
     34 */ 
     35 
     36enum { 
     37        LTQ_NOR_PROBING, 
     38        LTQ_NOR_NORMAL 
     39}; 
     40 
     41struct ltq_mtd { 
     42        struct resource *res; 
     43        struct mtd_info *mtd; 
     44        struct map_info *map; 
     45}; 
     46 
     47static char ltq_map_name[] = "ltq_nor"; 
     48 
     49static map_word 
     50ltq_read16(struct map_info *map, unsigned long adr) 
     51{ 
     52        unsigned long flags; 
     53        map_word temp; 
     54 
     55        if (map->map_priv_1 == LTQ_NOR_PROBING) 
     56                adr ^= 2; 
     57        spin_lock_irqsave(&ebu_lock, flags); 
     58        temp.x[0] = *(u16 *)(map->virt + adr); 
     59        spin_unlock_irqrestore(&ebu_lock, flags); 
     60        return temp; 
     61} 
     62 
     63static void 
     64ltq_write16(struct map_info *map, map_word d, unsigned long adr) 
     65{ 
     66        unsigned long flags; 
     67 
     68        if (map->map_priv_1 == LTQ_NOR_PROBING) 
     69                adr ^= 2; 
     70        spin_lock_irqsave(&ebu_lock, flags); 
     71        *(u16 *)(map->virt + adr) = d.x[0]; 
     72        spin_unlock_irqrestore(&ebu_lock, flags); 
     73} 
     74 
     75/* 
     76 * The following 2 functions copy data between iomem and a cached memory 
     77 * section. As memcpy() makes use of pre-fetching we cannot use it here. 
     78 * The normal alternative of using memcpy_{to,from}io also makes use of 
     79 * memcpy() on MIPS so it is not applicable either. We are therefore stuck 
     80 * with having to use our own loop. 
     81 */ 
     82static void 
     83ltq_copy_from(struct map_info *map, void *to, 
     84        unsigned long from, ssize_t len) 
     85{ 
     86        unsigned char *f = (unsigned char *)map->virt + from; 
     87        unsigned char *t = (unsigned char *)to; 
     88        unsigned long flags; 
     89 
     90        spin_lock_irqsave(&ebu_lock, flags); 
     91        while (len--) 
     92                *t++ = *f++; 
     93        spin_unlock_irqrestore(&ebu_lock, flags); 
     94} 
     95 
     96static void 
     97ltq_copy_to(struct map_info *map, unsigned long to, 
     98        const void *from, ssize_t len) 
     99{ 
     100        unsigned char *f = (unsigned char *)from; 
     101        unsigned char *t = (unsigned char *)map->virt + to; 
     102        unsigned long flags; 
     103 
     104        spin_lock_irqsave(&ebu_lock, flags); 
     105        while (len--) 
     106                *t++ = *f++; 
     107        spin_unlock_irqrestore(&ebu_lock, flags); 
     108} 
     109 
     110static const char const *part_probe_types[] = { "cmdlinepart", NULL }; 
     111 
     112static int __init 
     113ltq_mtd_probe(struct platform_device *pdev) 
     114{ 
     115        struct physmap_flash_data *ltq_mtd_data = dev_get_platdata(&pdev->dev); 
     116        struct ltq_mtd *ltq_mtd; 
     117        struct mtd_partition *parts; 
     118        struct resource *res; 
     119        int nr_parts = 0; 
     120        struct cfi_private *cfi; 
     121        int err; 
     122 
     123        ltq_mtd = kzalloc(sizeof(struct ltq_mtd), GFP_KERNEL); 
     124        platform_set_drvdata(pdev, ltq_mtd); 
     125 
     126        ltq_mtd->res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 
     127        if (!ltq_mtd->res) { 
     128                dev_err(&pdev->dev, "failed to get memory resource"); 
     129                err = -ENOENT; 
     130                goto err_out; 
     131        } 
     132 
     133        res = devm_request_mem_region(&pdev->dev, ltq_mtd->res->start, 
     134                resource_size(ltq_mtd->res), dev_name(&pdev->dev)); 
     135        if (!ltq_mtd->res) { 
     136                dev_err(&pdev->dev, "failed to request mem resource"); 
     137                err = -EBUSY; 
     138                goto err_out; 
     139        } 
     140 
     141        ltq_mtd->map = kzalloc(sizeof(struct map_info), GFP_KERNEL); 
     142        ltq_mtd->map->phys = res->start; 
     143        ltq_mtd->map->size = resource_size(res); 
     144        ltq_mtd->map->virt = devm_ioremap_nocache(&pdev->dev, 
     145                                ltq_mtd->map->phys, ltq_mtd->map->size); 
     146        if (!ltq_mtd->map->virt) { 
     147                dev_err(&pdev->dev, "failed to ioremap!\n"); 
     148                err = -ENOMEM; 
     149                goto err_free; 
     150        } 
     151 
     152        ltq_mtd->map->name = ltq_map_name; 
     153        ltq_mtd->map->bankwidth = 2; 
     154        ltq_mtd->map->read = ltq_read16; 
     155        ltq_mtd->map->write = ltq_write16; 
     156        ltq_mtd->map->copy_from = ltq_copy_from; 
     157        ltq_mtd->map->copy_to = ltq_copy_to; 
     158 
     159        ltq_mtd->map->map_priv_1 = LTQ_NOR_PROBING; 
     160        ltq_mtd->mtd = do_map_probe("cfi_probe", ltq_mtd->map); 
     161        ltq_mtd->map->map_priv_1 = LTQ_NOR_NORMAL; 
     162 
     163        if (!ltq_mtd->mtd) { 
     164                dev_err(&pdev->dev, "probing failed\n"); 
     165                err = -ENXIO; 
     166                goto err_unmap; 
     167        } 
     168 
     169        ltq_mtd->mtd->owner = THIS_MODULE; 
     170 
     171        cfi = ltq_mtd->map->fldrv_priv; 
     172        cfi->addr_unlock1 ^= 1; 
     173        cfi->addr_unlock2 ^= 1; 
     174 
     175        nr_parts = parse_mtd_partitions(ltq_mtd->mtd, 
     176                                part_probe_types, &parts, 0); 
     177        if (nr_parts > 0) { 
     178                dev_info(&pdev->dev, 
     179                        "using %d partitions from cmdline", nr_parts); 
     180        } else { 
     181                nr_parts = ltq_mtd_data->nr_parts; 
     182                parts = ltq_mtd_data->parts; 
     183        } 
     184 
     185        err = add_mtd_partitions(ltq_mtd->mtd, parts, nr_parts); 
     186        if (err) { 
     187                dev_err(&pdev->dev, "failed to add partitions\n"); 
     188                goto err_destroy; 
     189        } 
     190 
     191        return 0; 
     192 
     193err_destroy: 
     194        map_destroy(ltq_mtd->mtd); 
     195err_unmap: 
     196        iounmap(ltq_mtd->map->virt); 
     197err_free: 
     198        kfree(ltq_mtd->map); 
     199err_out: 
     200        kfree(ltq_mtd); 
     201        return err; 
     202} 
     203 
     204static int __devexit 
     205ltq_mtd_remove(struct platform_device *pdev) 
     206{ 
     207        struct ltq_mtd *ltq_mtd = platform_get_drvdata(pdev); 
     208 
     209        if (ltq_mtd) { 
     210                if (ltq_mtd->mtd) { 
     211                        del_mtd_partitions(ltq_mtd->mtd); 
     212                        map_destroy(ltq_mtd->mtd); 
     213                } 
     214                if (ltq_mtd->map->virt) 
     215                        iounmap(ltq_mtd->map->virt); 
     216                kfree(ltq_mtd->map); 
     217                kfree(ltq_mtd); 
     218        } 
     219        return 0; 
     220} 
     221 
     222static struct platform_driver ltq_mtd_driver = { 
     223        .remove = __devexit_p(ltq_mtd_remove), 
     224        .driver = { 
     225                .name = "ltq_nor", 
     226                .owner = THIS_MODULE, 
     227        }, 
     228}; 
     229 
     230static int __init 
     231init_ltq_mtd(void) 
     232{ 
     233        int ret = platform_driver_probe(&ltq_mtd_driver, ltq_mtd_probe); 
     234 
     235        if (ret) 
     236                pr_err("ltq_nor: error registering platform driver"); 
     237        return ret; 
     238} 
     239 
     240static void __exit 
     241exit_ltq_mtd(void) 
     242{ 
     243        platform_driver_unregister(&ltq_mtd_driver); 
     244} 
     245 
     246module_init(init_ltq_mtd); 
     247module_exit(exit_ltq_mtd); 
     248 
     249MODULE_LICENSE("GPL"); 
     250MODULE_AUTHOR("John Crispin <blogic@openwrt.org>"); 
     251MODULE_DESCRIPTION("Lantiq SoC NOR"); 
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