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Release 4.7 drivers/mtd/maps/sc520cdp.c

Directory: drivers/mtd/maps
/* sc520cdp.c -- MTD map driver for AMD SC520 Customer Development Platform
 *
 * Copyright (C) 2001 Sysgo Real-Time Solutions GmbH
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 *
 *
 * The SC520CDP is an evaluation board for the Elan SC520 processor available
 * from AMD. It has two banks of 32-bit Flash ROM, each 8 Megabytes in size,
 * and up to 512 KiB of 8-bit DIL Flash ROM.
 * For details see http://www.amd.com/products/epd/desiging/evalboards/18.elansc520/520_cdp_brief/index.html
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <asm/io.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/concat.h>

/*
** The Embedded Systems BIOS decodes the first FLASH starting at
** 0x8400000. This is a *terrible* place for it because accessing
** the flash at this location causes the A22 address line to be high
** (that's what 0x8400000 binary's ought to be). But this is the highest
** order address line on the raw flash devices themselves!!
** This causes the top HALF of the flash to be accessed first. Beyond
** the physical limits of the flash, the flash chip aliases over (to
** 0x880000 which causes the bottom half to be accessed. This splits the
** flash into two and inverts it! If you then try to access this from another
** program that does NOT do this insanity, then you *will* access the
** first half of the flash, but not find what you expect there. That
** stuff is in the *second* half! Similarly, the address used by the
** BIOS for the second FLASH bank is also quite a bad choice.
** If REPROGRAM_PAR is defined below (the default), then this driver will
** choose more useful addresses for the FLASH banks by reprogramming the
** responsible PARxx registers in the SC520's MMCR region. This will
** cause the settings to be incompatible with the BIOS's settings, which
** shouldn't be a problem since you are running Linux, (i.e. the BIOS is
** not much use anyway). However, if you need to be compatible with
** the BIOS for some reason, just undefine REPROGRAM_PAR.
*/

#define REPROGRAM_PAR



#ifdef REPROGRAM_PAR

/* These are the addresses we want.. */

#define WINDOW_ADDR_0	0x08800000

#define WINDOW_ADDR_1	0x09000000

#define WINDOW_ADDR_2	0x09800000

/* .. and these are the addresses the BIOS gives us */

#define WINDOW_ADDR_0_BIOS	0x08400000

#define WINDOW_ADDR_1_BIOS	0x08c00000

#define WINDOW_ADDR_2_BIOS	0x09400000

#else


#define WINDOW_ADDR_0	0x08400000

#define WINDOW_ADDR_1	0x08C00000

#define WINDOW_ADDR_2	0x09400000

#endif


#define WINDOW_SIZE_0	0x00800000

#define WINDOW_SIZE_1	0x00800000

#define WINDOW_SIZE_2	0x00080000



static struct map_info sc520cdp_map[] = {
	{
		.name = "SC520CDP Flash Bank #0",
		.size = WINDOW_SIZE_0,
		.bankwidth = 4,
		.phys = WINDOW_ADDR_0
	},
	{
		.name = "SC520CDP Flash Bank #1",
		.size = WINDOW_SIZE_1,
		.bankwidth = 4,
		.phys = WINDOW_ADDR_1
	},
	{
		.name = "SC520CDP DIL Flash",
		.size = WINDOW_SIZE_2,
		.bankwidth = 1,
		.phys = WINDOW_ADDR_2
	},
};


#define NUM_FLASH_BANKS	ARRAY_SIZE(sc520cdp_map)


static struct mtd_info *mymtd[NUM_FLASH_BANKS];

static struct mtd_info *merged_mtd;

#ifdef REPROGRAM_PAR

/*
** The SC520 MMCR (memory mapped control register) region resides
** at 0xFFFEF000. The 16 Programmable Address Region (PAR) registers
** are at offset 0x88 in the MMCR:
*/

#define SC520_MMCR_BASE		0xFFFEF000

#define SC520_MMCR_EXTENT	0x1000

#define SC520_PAR(x)		((0x88/sizeof(unsigned long)) + (x))

#define NUM_SC520_PAR		16	
/* total number of PAR registers */

/*
** The highest three bits in a PAR register determine what target
** device is controlled by this PAR. Here, only ROMCS? and BOOTCS
** devices are of interest.
*/

#define SC520_PAR_BOOTCS	(0x4<<29)

#define SC520_PAR_ROMCS0	(0x5<<29)

#define SC520_PAR_ROMCS1	(0x6<<29)

#define SC520_PAR_TRGDEV	(0x7<<29)

/*
** Bits 28 thru 26 determine some attributes for the
** region controlled by the PAR. (We only use non-cacheable)
*/

#define SC520_PAR_WRPROT	(1<<26)	
/* write protected       */

#define SC520_PAR_NOCACHE	(1<<27)	
/* non-cacheable         */

#define SC520_PAR_NOEXEC	(1<<28)	
/* code execution denied */


/*
** Bit 25 determines the granularity: 4K or 64K
*/

#define SC520_PAR_PG_SIZ4	(0<<25)

#define SC520_PAR_PG_SIZ64	(1<<25)

/*
** Build a value to be written into a PAR register.
** We only need ROM entries, 64K page size:
*/

#define SC520_PAR_ENTRY(trgdev, address, size) \
	((trgdev) | SC520_PAR_NOCACHE | SC520_PAR_PG_SIZ64 | \
        (address) >> 16 | (((size) >> 16) - 1) << 14)


struct sc520_par_table
{
	
unsigned long trgdev;
	
unsigned long new_par;
	
unsigned long default_address;
};


static const struct sc520_par_table par_table[NUM_FLASH_BANKS] =
{
	{	/* Flash Bank #0: selected by ROMCS0 */
		SC520_PAR_ROMCS0,
		SC520_PAR_ENTRY(SC520_PAR_ROMCS0, WINDOW_ADDR_0, WINDOW_SIZE_0),
		WINDOW_ADDR_0_BIOS
	},
	{	/* Flash Bank #1: selected by ROMCS1 */
		SC520_PAR_ROMCS1,
		SC520_PAR_ENTRY(SC520_PAR_ROMCS1, WINDOW_ADDR_1, WINDOW_SIZE_1),
		WINDOW_ADDR_1_BIOS
	},
	{	/* DIL (BIOS) Flash: selected by BOOTCS */
		SC520_PAR_BOOTCS,
		SC520_PAR_ENTRY(SC520_PAR_BOOTCS, WINDOW_ADDR_2, WINDOW_SIZE_2),
		WINDOW_ADDR_2_BIOS
	}
};



static void sc520cdp_setup_par(void) { unsigned long __iomem *mmcr; unsigned long mmcr_val; int i, j; /* map in SC520's MMCR area */ mmcr = ioremap_nocache(SC520_MMCR_BASE, SC520_MMCR_EXTENT); if(!mmcr) { /* ioremap_nocache failed: skip the PAR reprogramming */ /* force physical address fields to BIOS defaults: */ for(i = 0; i < NUM_FLASH_BANKS; i++) sc520cdp_map[i].phys = par_table[i].default_address; return; } /* ** Find the PARxx registers that are responsible for activating ** ROMCS0, ROMCS1 and BOOTCS. Reprogram each of these with a ** new value from the table. */ for(i = 0; i < NUM_FLASH_BANKS; i++) { /* for each par_table entry */ for(j = 0; j < NUM_SC520_PAR; j++) { /* for each PAR register */ mmcr_val = readl(&mmcr[SC520_PAR(j)]); /* if target device field matches, reprogram the PAR */ if((mmcr_val & SC520_PAR_TRGDEV) == par_table[i].trgdev) { writel(par_table[i].new_par, &mmcr[SC520_PAR(j)]); break; } } if(j == NUM_SC520_PAR) { /* no matching PAR found: try default BIOS address */ printk(KERN_NOTICE "Could not find PAR responsible for %s\n", sc520cdp_map[i].name); printk(KERN_NOTICE "Trying default address 0x%lx\n", par_table[i].default_address); sc520cdp_map[i].phys = par_table[i].default_address; } } iounmap(mmcr); }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds18990.43%120.00%
brian norrisbrian norris157.18%120.00%
david woodhousedavid woodhouse41.91%240.00%
lucas de marchilucas de marchi10.48%120.00%
Total209100.00%5100.00%

#endif
static int __init init_sc520cdp(void) { int i, devices_found = 0; #ifdef REPROGRAM_PAR /* reprogram PAR registers so flash appears at the desired addresses */ sc520cdp_setup_par(); #endif for (i = 0; i < NUM_FLASH_BANKS; i++) { printk(KERN_NOTICE "SC520 CDP flash device: 0x%Lx at 0x%Lx\n", (unsigned long long)sc520cdp_map[i].size, (unsigned long long)sc520cdp_map[i].phys); sc520cdp_map[i].virt = ioremap_nocache(sc520cdp_map[i].phys, sc520cdp_map[i].size); if (!sc520cdp_map[i].virt) { printk("Failed to ioremap_nocache\n"); return -EIO; } simple_map_init(&sc520cdp_map[i]); mymtd[i] = do_map_probe("cfi_probe", &sc520cdp_map[i]); if(!mymtd[i]) mymtd[i] = do_map_probe("jedec_probe", &sc520cdp_map[i]); if(!mymtd[i]) mymtd[i] = do_map_probe("map_rom", &sc520cdp_map[i]); if (mymtd[i]) { mymtd[i]->owner = THIS_MODULE; ++devices_found; } else { iounmap(sc520cdp_map[i].virt); } } if(devices_found >= 2) { /* Combine the two flash banks into a single MTD device & register it: */ merged_mtd = mtd_concat_create(mymtd, 2, "SC520CDP Flash Banks #0 and #1"); if(merged_mtd) mtd_device_register(merged_mtd, NULL, 0); } if(devices_found == 3) /* register the third (DIL-Flash) device */ mtd_device_register(mymtd[2], NULL, 0); return(devices_found ? 0 : -ENXIO); }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds20572.18%240.00%
david woodhousedavid woodhouse5820.42%120.00%
andrew mortonandrew morton113.87%120.00%
jamie ilesjamie iles103.52%120.00%
Total284100.00%5100.00%


static void __exit cleanup_sc520cdp(void) { int i; if (merged_mtd) { mtd_device_unregister(merged_mtd); mtd_concat_destroy(merged_mtd); } if (mymtd[2]) mtd_device_unregister(mymtd[2]); for (i = 0; i < NUM_FLASH_BANKS; i++) { if (mymtd[i]) map_destroy(mymtd[i]); if (sc520cdp_map[i].virt) { iounmap(sc520cdp_map[i].virt); sc520cdp_map[i].virt = NULL; } } }

Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds6866.02%125.00%
david woodhousedavid woodhouse3332.04%250.00%
jamie ilesjamie iles21.94%125.00%
Total103100.00%4100.00%

module_init(init_sc520cdp); module_exit(cleanup_sc520cdp); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Sysgo Real-Time Solutions GmbH"); MODULE_DESCRIPTION("MTD map driver for AMD SC520 Customer Development Platform");

Overall Contributors

PersonTokensPropCommitsCommitProp
linus torvaldslinus torvalds77881.30%215.38%
david woodhousedavid woodhouse11411.91%430.77%
art haasart haas242.51%17.69%
brian norrisbrian norris151.57%17.69%
jamie ilesjamie iles121.25%17.69%
andrew mortonandrew morton111.15%17.69%
tobias klausertobias klauser10.10%17.69%
adrian bunkadrian bunk10.10%17.69%
lucas de marchilucas de marchi10.10%17.69%
Total957100.00%13100.00%
Directory: drivers/mtd/maps
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