| /* 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 |
| * |
| * $Id: sc520cdp.c,v 1.23 2005/11/17 08:20:27 dwmw2 Exp $ |
| * |
| * |
| * 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/config.h> |
| #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) |
| { |
| volatile 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 reponsible 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 = mmcr[SC520_PAR(j)]; |
| /* if target device field matches, reprogram the PAR */ |
| if((mmcr_val & SC520_PAR_TRGDEV) == par_table[i].trgdev) |
| { |
| mmcr[SC520_PAR(j)] = par_table[i].new_par; |
| 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); |
| } |
| #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", |
| sc520cdp_map[i].size, 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) |
| add_mtd_device(merged_mtd); |
| } |
| if(devices_found == 3) /* register the third (DIL-Flash) device */ |
| add_mtd_device(mymtd[2]); |
| return(devices_found ? 0 : -ENXIO); |
| } |
| |
| static void __exit cleanup_sc520cdp(void) |
| { |
| int i; |
| |
| if (merged_mtd) { |
| del_mtd_device(merged_mtd); |
| mtd_concat_destroy(merged_mtd); |
| } |
| if (mymtd[2]) |
| del_mtd_device(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; |
| } |
| } |
| } |
| |
| 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"); |