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Diffstat (limited to 'drivers/systemace.c')
| -rw-r--r-- | drivers/systemace.c | 264 |
1 files changed, 264 insertions, 0 deletions
diff --git a/drivers/systemace.c b/drivers/systemace.c new file mode 100644 index 0000000..8dd98d0 --- /dev/null +++ b/drivers/systemace.c @@ -0,0 +1,264 @@ +/* + * Copyright (c) 2004 Picture Elements, Inc. + * Stephen Williams (XXXXXXXXXXXXXXXX) + * + * This source code is free software; you can redistribute it + * and/or modify it in source code form 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 Xilinx SystemACE chip support is activated by defining + * CONFIG_SYSTEMACE to turn on support, and CFG_SYSTEMACE_BASE + * to set the base address of the device. This code currently + * assumes that the chip is connected via a byte-wide bus. + * + * The CONFIG_SYSTEMACE also adds to fat support the device class + * "ace" that allows the user to execute "fatls ace 0" and the + * like. This works by making the systemace_get_dev function + * available to cmd_fat.c:get_dev and filling in a block device + * description that has all the bits needed for FAT support to + * read sectors. + * + * According to Xilinx technical support, before accessing the + * SystemACE CF you need to set the following control bits: + * FORCECFGMODE : 1 + * CFGMODE : 0 + * CFGSTART : 0 + */ + +#include <common.h> +#include <command.h> +#include <systemace.h> +#include <part.h> +#include <asm/io.h> + +#ifdef CONFIG_SYSTEMACE + +/* + * The ace_readw and writew functions read/write 16bit words, but the + * offset value is the BYTE offset as most used in the Xilinx + * datasheet for the SystemACE chip. The CFG_SYSTEMACE_BASE is defined + * to be the base address for the chip, usually in the local + * peripheral bus. + */ +static unsigned ace_readw(unsigned offset) +{ +#if (CFG_SYSTEMACE_WIDTH == 8) + u16 temp; + +#if !defined(__BIG_ENDIAN) + temp = ((u16) readb(CFG_SYSTEMACE_BASE + offset) << 8); + temp |= (u16) readb(CFG_SYSTEMACE_BASE + offset + 1); +#else + temp = (u16) readb(CFG_SYSTEMACE_BASE + offset); + temp |= ((u16) readb(CFG_SYSTEMACE_BASE + offset + 1) << 8); +#endif + return temp; +#else + return readw(CFG_SYSTEMACE_BASE + offset); +#endif +} + +static void ace_writew(unsigned val, unsigned offset) +{ +#if (CFG_SYSTEMACE_WIDTH == 8) +#if !defined(__BIG_ENDIAN) + writeb((u8) (val >> 8), CFG_SYSTEMACE_BASE + offset); + writeb((u8) val, CFG_SYSTEMACE_BASE + offset + 1); +#else + writeb((u8) val, CFG_SYSTEMACE_BASE + offset); + writeb((u8) (val >> 8), CFG_SYSTEMACE_BASE + offset + 1); +#endif +#else + writew(val, CFG_SYSTEMACE_BASE + offset); +#endif +} + +/* */ + +static unsigned long systemace_read(int dev, unsigned long start, + unsigned long blkcnt, + unsigned long *buffer); + +static block_dev_desc_t systemace_dev = { 0 }; + +static int get_cf_lock(void) +{ + int retry = 10; + + /* CONTROLREG = LOCKREG */ + unsigned val = ace_readw(0x18); + val |= 0x0002; + ace_writew((val & 0xffff), 0x18); + + /* Wait for MPULOCK in STATUSREG[15:0] */ + while (!(ace_readw(0x04) & 0x0002)) { + + if (retry < 0) + return -1; + + udelay(100000); + retry -= 1; + } + + return 0; +} + +static void release_cf_lock(void) +{ + unsigned val = ace_readw(0x18); + val &= ~(0x0002); + ace_writew((val & 0xffff), 0x18); +} + +block_dev_desc_t *systemace_get_dev(int dev) +{ + /* The first time through this, the systemace_dev object is + not yet initialized. In that case, fill it in. */ + if (systemace_dev.blksz == 0) { + systemace_dev.if_type = IF_TYPE_UNKNOWN; + systemace_dev.dev = 0; + systemace_dev.part_type = PART_TYPE_UNKNOWN; + systemace_dev.type = DEV_TYPE_HARDDISK; + systemace_dev.blksz = 512; + systemace_dev.removable = 1; + systemace_dev.block_read = systemace_read; + + init_part(&systemace_dev); + + } + + return &systemace_dev; +} + +/* + * This function is called (by dereferencing the block_read pointer in + * the dev_desc) to read blocks of data. The return value is the + * number of blocks read. A zero return indicates an error. + */ +static unsigned long systemace_read(int dev, unsigned long start, + unsigned long blkcnt, unsigned long *buffer) +{ + int retry; + unsigned blk_countdown; + unsigned char *dp = (unsigned char *)buffer; + unsigned val; + + if (get_cf_lock() < 0) { + unsigned status = ace_readw(0x04); + + /* If CFDETECT is false, card is missing. */ + if (!(status & 0x0010)) { + printf("** CompactFlash card not present. **\n"); + return 0; + } + + printf("**** ACE locked away from me (STATUSREG=%04x)\n", + status); + return 0; + } +#ifdef DEBUG_SYSTEMACE + printf("... systemace read %lu sectors at %lu\n", blkcnt, start); +#endif + + retry = 2000; + for (;;) { + val = ace_readw(0x04); + + /* If CFDETECT is false, card is missing. */ + if (!(val & 0x0010)) { + printf("**** ACE CompactFlash not found.\n"); + release_cf_lock(); + return 0; + } + + /* If RDYFORCMD, then we are ready to go. */ + if (val & 0x0100) + break; + + if (retry < 0) { + printf("**** SystemACE not ready.\n"); + release_cf_lock(); + return 0; + } + + udelay(1000); + retry -= 1; + } + + /* The SystemACE can only transfer 256 sectors at a time, so + limit the current chunk of sectors. The blk_countdown + variable is the number of sectors left to transfer. */ + + blk_countdown = blkcnt; + while (blk_countdown > 0) { + unsigned trans = blk_countdown; + + if (trans > 256) + trans = 256; + +#ifdef DEBUG_SYSTEMACE + printf("... transfer %lu sector in a chunk\n", trans); +#endif + /* Write LBA block address */ + ace_writew((start >> 0) & 0xffff, 0x10); + ace_writew((start >> 16) & 0x00ff, 0x12); + + /* NOTE: in the Write Sector count below, a count of 0 + causes a transfer of 256, so &0xff gives the right + value for whatever transfer count we want. */ + + /* Write sector count | ReadMemCardData. */ + ace_writew((trans & 0xff) | 0x0300, 0x14); + + /* Reset the configruation controller */ + val = ace_readw(0x18); + val |= 0x0080; + ace_writew(val, 0x18); + + retry = trans * 16; + while (retry > 0) { + int idx; + + /* Wait for buffer to become ready. */ + while (!(ace_readw(0x04) & 0x0020)) { + udelay(100); + } + + /* Read 16 words of 2bytes from the sector buffer. */ + for (idx = 0; idx < 16; idx += 1) { + unsigned short val = ace_readw(0x40); + *dp++ = val & 0xff; + *dp++ = (val >> 8) & 0xff; + } + + retry -= 1; + } + + /* Clear the configruation controller reset */ + val = ace_readw(0x18); + val &= ~0x0080; + ace_writew(val, 0x18); + + /* Count the blocks we transfer this time. */ + start += trans; + blk_countdown -= trans; + } + + release_cf_lock(); + + return blkcnt; +} +#endif /* CONFIG_SYSTEMACE */ |