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-rw-r--r--drivers/mtd/devices/docg3.c1114
1 files changed, 1114 insertions, 0 deletions
diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c
new file mode 100644
index 0000000..bdcf5df
--- /dev/null
+++ b/drivers/mtd/devices/docg3.c
@@ -0,0 +1,1114 @@
+/*
+ * Handles the M-Systems DiskOnChip G3 chip
+ *
+ * Copyright (C) 2011 Robert Jarzmik
+ *
+ * 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
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/platform_device.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+
+#define CREATE_TRACE_POINTS
+#include "docg3.h"
+
+/*
+ * This driver handles the DiskOnChip G3 flash memory.
+ *
+ * As no specification is available from M-Systems/Sandisk, this drivers lacks
+ * several functions available on the chip, as :
+ * - block erase
+ * - page write
+ * - IPL write
+ * - ECC fixing (lack of BCH algorith understanding)
+ * - powerdown / powerup
+ *
+ * The bus data width (8bits versus 16bits) is not handled (if_cfg flag), and
+ * the driver assumes a 16bits data bus.
+ *
+ * DocG3 relies on 2 ECC algorithms, which are handled in hardware :
+ * - a 1 byte Hamming code stored in the OOB for each page
+ * - a 7 bytes BCH code stored in the OOB for each page
+ * The BCH part is only used for check purpose, no correction is available as
+ * some information is missing. What is known is that :
+ * - BCH is in GF(2^14)
+ * - BCH is over data of 520 bytes (512 page + 7 page_info bytes
+ * + 1 hamming byte)
+ * - BCH can correct up to 4 bits (t = 4)
+ * - BCH syndroms are calculated in hardware, and checked in hardware as well
+ *
+ */
+
+static inline u8 doc_readb(struct docg3 *docg3, u16 reg)
+{
+ u8 val = readb(docg3->base + reg);
+
+ trace_docg3_io(0, 8, reg, (int)val);
+ return val;
+}
+
+static inline u16 doc_readw(struct docg3 *docg3, u16 reg)
+{
+ u16 val = readw(docg3->base + reg);
+
+ trace_docg3_io(0, 16, reg, (int)val);
+ return val;
+}
+
+static inline void doc_writeb(struct docg3 *docg3, u8 val, u16 reg)
+{
+ writeb(val, docg3->base + reg);
+ trace_docg3_io(1, 16, reg, val);
+}
+
+static inline void doc_writew(struct docg3 *docg3, u16 val, u16 reg)
+{
+ writew(val, docg3->base + reg);
+ trace_docg3_io(1, 16, reg, val);
+}
+
+static inline void doc_flash_command(struct docg3 *docg3, u8 cmd)
+{
+ doc_writeb(docg3, cmd, DOC_FLASHCOMMAND);
+}
+
+static inline void doc_flash_sequence(struct docg3 *docg3, u8 seq)
+{
+ doc_writeb(docg3, seq, DOC_FLASHSEQUENCE);
+}
+
+static inline void doc_flash_address(struct docg3 *docg3, u8 addr)
+{
+ doc_writeb(docg3, addr, DOC_FLASHADDRESS);
+}
+
+static char const *part_probes[] = { "cmdlinepart", "saftlpart", NULL };
+
+static int doc_register_readb(struct docg3 *docg3, int reg)
+{
+ u8 val;
+
+ doc_writew(docg3, reg, DOC_READADDRESS);
+ val = doc_readb(docg3, reg);
+ doc_vdbg("Read register %04x : %02x\n", reg, val);
+ return val;
+}
+
+static int doc_register_readw(struct docg3 *docg3, int reg)
+{
+ u16 val;
+
+ doc_writew(docg3, reg, DOC_READADDRESS);
+ val = doc_readw(docg3, reg);
+ doc_vdbg("Read register %04x : %04x\n", reg, val);
+ return val;
+}
+
+/**
+ * doc_delay - delay docg3 operations
+ * @docg3: the device
+ * @nbNOPs: the number of NOPs to issue
+ *
+ * As no specification is available, the right timings between chip commands are
+ * unknown. The only available piece of information are the observed nops on a
+ * working docg3 chip.
+ * Therefore, doc_delay relies on a busy loop of NOPs, instead of scheduler
+ * friendlier msleep() functions or blocking mdelay().
+ */
+static void doc_delay(struct docg3 *docg3, int nbNOPs)
+{
+ int i;
+
+ doc_dbg("NOP x %d\n", nbNOPs);
+ for (i = 0; i < nbNOPs; i++)
+ doc_writeb(docg3, 0, DOC_NOP);
+}
+
+static int is_prot_seq_error(struct docg3 *docg3)
+{
+ int ctrl;
+
+ ctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
+ return ctrl & (DOC_CTRL_PROTECTION_ERROR | DOC_CTRL_SEQUENCE_ERROR);
+}
+
+static int doc_is_ready(struct docg3 *docg3)
+{
+ int ctrl;
+
+ ctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
+ return ctrl & DOC_CTRL_FLASHREADY;
+}
+
+static int doc_wait_ready(struct docg3 *docg3)
+{
+ int maxWaitCycles = 100;
+
+ do {
+ doc_delay(docg3, 4);
+ cpu_relax();
+ } while (!doc_is_ready(docg3) && maxWaitCycles--);
+ doc_delay(docg3, 2);
+ if (maxWaitCycles > 0)
+ return 0;
+ else
+ return -EIO;
+}
+
+static int doc_reset_seq(struct docg3 *docg3)
+{
+ int ret;
+
+ doc_writeb(docg3, 0x10, DOC_FLASHCONTROL);
+ doc_flash_sequence(docg3, DOC_SEQ_RESET);
+ doc_flash_command(docg3, DOC_CMD_RESET);
+ doc_delay(docg3, 2);
+ ret = doc_wait_ready(docg3);
+
+ doc_dbg("doc_reset_seq() -> isReady=%s\n", ret ? "false" : "true");
+ return ret;
+}
+
+/**
+ * doc_read_data_area - Read data from data area
+ * @docg3: the device
+ * @buf: the buffer to fill in
+ * @len: the lenght to read
+ * @first: first time read, DOC_READADDRESS should be set
+ *
+ * Reads bytes from flash data. Handles the single byte / even bytes reads.
+ */
+static void doc_read_data_area(struct docg3 *docg3, void *buf, int len,
+ int first)
+{
+ int i, cdr, len4;
+ u16 data16, *dst16;
+ u8 data8, *dst8;
+
+ doc_dbg("doc_read_data_area(buf=%p, len=%d)\n", buf, len);
+ cdr = len & 0x3;
+ len4 = len - cdr;
+
+ if (first)
+ doc_writew(docg3, DOC_IOSPACE_DATA, DOC_READADDRESS);
+ dst16 = buf;
+ for (i = 0; i < len4; i += 2) {
+ data16 = doc_readw(docg3, DOC_IOSPACE_DATA);
+ *dst16 = data16;
+ dst16++;
+ }
+
+ if (cdr) {
+ doc_writew(docg3, DOC_IOSPACE_DATA | DOC_READADDR_ONE_BYTE,
+ DOC_READADDRESS);
+ doc_delay(docg3, 1);
+ dst8 = (u8 *)dst16;
+ for (i = 0; i < cdr; i++) {
+ data8 = doc_readb(docg3, DOC_IOSPACE_DATA);
+ *dst8 = data8;
+ dst8++;
+ }
+ }
+}
+
+/**
+ * doc_set_data_mode - Sets the flash to reliable data mode
+ * @docg3: the device
+ *
+ * The reliable data mode is a bit slower than the fast mode, but less errors
+ * occur. Entering the reliable mode cannot be done without entering the fast
+ * mode first.
+ */
+static void doc_set_reliable_mode(struct docg3 *docg3)
+{
+ doc_dbg("doc_set_reliable_mode()\n");
+ doc_flash_sequence(docg3, DOC_SEQ_SET_MODE);
+ doc_flash_command(docg3, DOC_CMD_FAST_MODE);
+ doc_flash_command(docg3, DOC_CMD_RELIABLE_MODE);
+ doc_delay(docg3, 2);
+}
+
+/**
+ * doc_set_asic_mode - Set the ASIC mode
+ * @docg3: the device
+ * @mode: the mode
+ *
+ * The ASIC can work in 3 modes :
+ * - RESET: all registers are zeroed
+ * - NORMAL: receives and handles commands
+ * - POWERDOWN: minimal poweruse, flash parts shut off
+ */
+static void doc_set_asic_mode(struct docg3 *docg3, u8 mode)
+{
+ int i;
+
+ for (i = 0; i < 12; i++)
+ doc_readb(docg3, DOC_IOSPACE_IPL);
+
+ mode |= DOC_ASICMODE_MDWREN;
+ doc_dbg("doc_set_asic_mode(%02x)\n", mode);
+ doc_writeb(docg3, mode, DOC_ASICMODE);
+ doc_writeb(docg3, ~mode, DOC_ASICMODECONFIRM);
+ doc_delay(docg3, 1);
+}
+
+/**
+ * doc_set_device_id - Sets the devices id for cascaded G3 chips
+ * @docg3: the device
+ * @id: the chip to select (amongst 0, 1, 2, 3)
+ *
+ * There can be 4 cascaded G3 chips. This function selects the one which will
+ * should be the active one.
+ */
+static void doc_set_device_id(struct docg3 *docg3, int id)
+{
+ u8 ctrl;
+
+ doc_dbg("doc_set_device_id(%d)\n", id);
+ doc_writeb(docg3, id, DOC_DEVICESELECT);
+ ctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
+
+ ctrl &= ~DOC_CTRL_VIOLATION;
+ ctrl |= DOC_CTRL_CE;
+ doc_writeb(docg3, ctrl, DOC_FLASHCONTROL);
+}
+
+/**
+ * doc_set_extra_page_mode - Change flash page layout
+ * @docg3: the device
+ *
+ * Normally, the flash page is split into the data (512 bytes) and the out of
+ * band data (16 bytes). For each, 4 more bytes can be accessed, where the wear
+ * leveling counters are stored. To access this last area of 4 bytes, a special
+ * mode must be input to the flash ASIC.
+ *
+ * Returns 0 if no error occured, -EIO else.
+ */
+static int doc_set_extra_page_mode(struct docg3 *docg3)
+{
+ int fctrl;
+
+ doc_dbg("doc_set_extra_page_mode()\n");
+ doc_flash_sequence(docg3, DOC_SEQ_PAGE_SIZE_532);
+ doc_flash_command(docg3, DOC_CMD_PAGE_SIZE_532);
+ doc_delay(docg3, 2);
+
+ fctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
+ if (fctrl & (DOC_CTRL_PROTECTION_ERROR | DOC_CTRL_SEQUENCE_ERROR))
+ return -EIO;
+ else
+ return 0;
+}
+
+/**
+ * doc_seek - Set both flash planes to the specified block, page for reading
+ * @docg3: the device
+ * @block0: the first plane block index
+ * @block1: the second plane block index
+ * @page: the page index within the block
+ * @wear: if true, read will occur on the 4 extra bytes of the wear area
+ * @ofs: offset in page to read
+ *
+ * Programs the flash even and odd planes to the specific block and page.
+ * Alternatively, programs the flash to the wear area of the specified page.
+ */
+static int doc_read_seek(struct docg3 *docg3, int block0, int block1, int page,
+ int wear, int ofs)
+{
+ int sector, ret = 0;
+
+ doc_dbg("doc_seek(blocks=(%d,%d), page=%d, ofs=%d, wear=%d)\n",
+ block0, block1, page, ofs, wear);
+
+ if (!wear && (ofs < 2 * DOC_LAYOUT_PAGE_SIZE)) {
+ doc_flash_sequence(docg3, DOC_SEQ_SET_PLANE1);
+ doc_flash_command(docg3, DOC_CMD_READ_PLANE1);
+ doc_delay(docg3, 2);
+ } else {
+ doc_flash_sequence(docg3, DOC_SEQ_SET_PLANE2);
+ doc_flash_command(docg3, DOC_CMD_READ_PLANE2);
+ doc_delay(docg3, 2);
+ }
+
+ doc_set_reliable_mode(docg3);
+ if (wear)
+ ret = doc_set_extra_page_mode(docg3);
+ if (ret)
+ goto out;
+
+ sector = (block0 << DOC_ADDR_BLOCK_SHIFT) + (page & DOC_ADDR_PAGE_MASK);
+ doc_flash_sequence(docg3, DOC_SEQ_READ);
+ doc_flash_command(docg3, DOC_CMD_PROG_BLOCK_ADDR);
+ doc_delay(docg3, 1);
+ doc_flash_address(docg3, sector & 0xff);
+ doc_flash_address(docg3, (sector >> 8) & 0xff);
+ doc_flash_address(docg3, (sector >> 16) & 0xff);
+ doc_delay(docg3, 1);
+
+ sector = (block1 << DOC_ADDR_BLOCK_SHIFT) + (page & DOC_ADDR_PAGE_MASK);
+ doc_flash_command(docg3, DOC_CMD_PROG_BLOCK_ADDR);
+ doc_delay(docg3, 1);
+ doc_flash_address(docg3, sector & 0xff);
+ doc_flash_address(docg3, (sector >> 8) & 0xff);
+ doc_flash_address(docg3, (sector >> 16) & 0xff);
+ doc_delay(docg3, 2);
+
+out:
+ return ret;
+}
+
+/**
+ * doc_read_page_ecc_init - Initialize hardware ECC engine
+ * @docg3: the device
+ * @len: the number of bytes covered by the ECC (BCH covered)
+ *
+ * The function does initialize the hardware ECC engine to compute the Hamming
+ * ECC (on 1 byte) and the BCH Syndroms (on 7 bytes).
+ *
+ * Return 0 if succeeded, -EIO on error
+ */
+static int doc_read_page_ecc_init(struct docg3 *docg3, int len)
+{
+ doc_writew(docg3, DOC_ECCCONF0_READ_MODE
+ | DOC_ECCCONF0_BCH_ENABLE | DOC_ECCCONF0_HAMMING_ENABLE
+ | (len & DOC_ECCCONF0_DATA_BYTES_MASK),
+ DOC_ECCCONF0);
+ doc_delay(docg3, 4);
+ doc_register_readb(docg3, DOC_FLASHCONTROL);
+ return doc_wait_ready(docg3);
+}
+
+/**
+ * doc_read_page_prepare - Prepares reading data from a flash page
+ * @docg3: the device
+ * @block0: the first plane block index on flash memory
+ * @block1: the second plane block index on flash memory
+ * @page: the page index in the block
+ * @offset: the offset in the page (must be a multiple of 4)
+ *
+ * Prepares the page to be read in the flash memory :
+ * - tell ASIC to map the flash pages
+ * - tell ASIC to be in read mode
+ *
+ * After a call to this method, a call to doc_read_page_finish is mandatory,
+ * to end the read cycle of the flash.
+ *
+ * Read data from a flash page. The length to be read must be between 0 and
+ * (page_size + oob_size + wear_size), ie. 532, and a multiple of 4 (because
+ * the extra bytes reading is not implemented).
+ *
+ * As pages are grouped by 2 (in 2 planes), reading from a page must be done
+ * in two steps:
+ * - one read of 512 bytes at offset 0
+ * - one read of 512 bytes at offset 512 + 16
+ *
+ * Returns 0 if successful, -EIO if a read error occured.
+ */
+static int doc_read_page_prepare(struct docg3 *docg3, int block0, int block1,
+ int page, int offset)
+{
+ int wear_area = 0, ret = 0;
+
+ doc_dbg("doc_read_page_prepare(blocks=(%d,%d), page=%d, ofsInPage=%d)\n",
+ block0, block1, page, offset);
+ if (offset >= DOC_LAYOUT_WEAR_OFFSET)
+ wear_area = 1;
+ if (!wear_area && offset > (DOC_LAYOUT_PAGE_OOB_SIZE * 2))
+ return -EINVAL;
+
+ doc_set_device_id(docg3, docg3->device_id);
+ ret = doc_reset_seq(docg3);
+ if (ret)
+ goto err;
+
+ /* Program the flash address block and page */
+ ret = doc_read_seek(docg3, block0, block1, page, wear_area, offset);
+ if (ret)
+ goto err;
+
+ doc_flash_command(docg3, DOC_CMD_READ_ALL_PLANES);
+ doc_delay(docg3, 2);
+ doc_wait_ready(docg3);
+
+ doc_flash_command(docg3, DOC_CMD_SET_ADDR_READ);
+ doc_delay(docg3, 1);
+ if (offset >= DOC_LAYOUT_PAGE_SIZE * 2)
+ offset -= 2 * DOC_LAYOUT_PAGE_SIZE;
+ doc_flash_address(docg3, offset >> 2);
+ doc_delay(docg3, 1);
+ doc_wait_ready(docg3);
+
+ doc_flash_command(docg3, DOC_CMD_READ_FLASH);
+
+ return 0;
+err:
+ doc_writeb(docg3, 0, DOC_DATAEND);
+ doc_delay(docg3, 2);
+ return -EIO;
+}
+
+/**
+ * doc_read_page_getbytes - Reads bytes from a prepared page
+ * @docg3: the device
+ * @len: the number of bytes to be read (must be a multiple of 4)
+ * @buf: the buffer to be filled in
+ * @first: 1 if first time read, DOC_READADDRESS should be set
+ *
+ */
+static int doc_read_page_getbytes(struct docg3 *docg3, int len, u_char *buf,
+ int first)
+{
+ doc_read_data_area(docg3, buf, len, first);
+ doc_delay(docg3, 2);
+ return len;
+}
+
+/**
+ * doc_get_hw_bch_syndroms - Get hardware calculated BCH syndroms
+ * @docg3: the device
+ * @syns: the array of 7 integers where the syndroms will be stored
+ */
+static void doc_get_hw_bch_syndroms(struct docg3 *docg3, int *syns)
+{
+ int i;
+
+ for (i = 0; i < DOC_ECC_BCH_SIZE; i++)
+ syns[i] = doc_register_readb(docg3, DOC_BCH_SYNDROM(i));
+}
+
+/**
+ * doc_read_page_finish - Ends reading of a flash page
+ * @docg3: the device
+ *
+ * As a side effect, resets the chip selector to 0. This ensures that after each
+ * read operation, the floor 0 is selected. Therefore, if the systems halts, the
+ * reboot will boot on floor 0, where the IPL is.
+ */
+static void doc_read_page_finish(struct docg3 *docg3)
+{
+ doc_writeb(docg3, 0, DOC_DATAEND);
+ doc_delay(docg3, 2);
+ doc_set_device_id(docg3, 0);
+}
+
+/**
+ * calc_block_sector - Calculate blocks, pages and ofs.
+
+ * @from: offset in flash
+ * @block0: first plane block index calculated
+ * @block1: second plane block index calculated
+ * @page: page calculated
+ * @ofs: offset in page
+ */
+static void calc_block_sector(loff_t from, int *block0, int *block1, int *page,
+ int *ofs)
+{
+ uint sector;
+
+ sector = from / DOC_LAYOUT_PAGE_SIZE;
+ *block0 = sector / (DOC_LAYOUT_PAGES_PER_BLOCK * DOC_LAYOUT_NBPLANES)
+ * DOC_LAYOUT_NBPLANES;
+ *block1 = *block0 + 1;
+ *page = sector % (DOC_LAYOUT_PAGES_PER_BLOCK * DOC_LAYOUT_NBPLANES);
+ *page /= DOC_LAYOUT_NBPLANES;
+ if (sector % 2)
+ *ofs = DOC_LAYOUT_PAGE_OOB_SIZE;
+ else
+ *ofs = 0;
+}
+
+/**
+ * doc_read - Read bytes from flash
+ * @mtd: the device
+ * @from: the offset from first block and first page, in bytes, aligned on page
+ * size
+ * @len: the number of bytes to read (must be a multiple of 4)
+ * @retlen: the number of bytes actually read
+ * @buf: the filled in buffer
+ *
+ * Reads flash memory pages. This function does not read the OOB chunk, but only
+ * the page data.
+ *
+ * Returns 0 if read successfull, of -EIO, -EINVAL if an error occured
+ */
+static int doc_read(struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, u_char *buf)
+{
+ struct docg3 *docg3 = mtd->priv;
+ int block0, block1, page, readlen, ret, ofs = 0;
+ int syn[DOC_ECC_BCH_SIZE], eccconf1;
+ u8 oob[DOC_LAYOUT_OOB_SIZE];
+
+ ret = -EINVAL;
+ doc_dbg("doc_read(from=%lld, len=%zu, buf=%p)\n", from, len, buf);
+ if (from % DOC_LAYOUT_PAGE_SIZE)
+ goto err;
+ if (len % 4)
+ goto err;
+ calc_block_sector(from, &block0, &block1, &page, &ofs);
+ if (block1 > docg3->max_block)
+ goto err;
+
+ *retlen = 0;
+ ret = 0;
+ readlen = min_t(size_t, len, (size_t)DOC_LAYOUT_PAGE_SIZE);
+ while (!ret && len > 0) {
+ readlen = min_t(size_t, len, (size_t)DOC_LAYOUT_PAGE_SIZE);
+ ret = doc_read_page_prepare(docg3, block0, block1, page, ofs);
+ if (ret < 0)
+ goto err;
+ ret = doc_read_page_ecc_init(docg3, DOC_ECC_BCH_COVERED_BYTES);
+ if (ret < 0)
+ goto err_in_read;
+ ret = doc_read_page_getbytes(docg3, readlen, buf, 1);
+ if (ret < readlen)
+ goto err_in_read;
+ ret = doc_read_page_getbytes(docg3, DOC_LAYOUT_OOB_SIZE,
+ oob, 0);
+ if (ret < DOC_LAYOUT_OOB_SIZE)
+ goto err_in_read;
+
+ *retlen += readlen;
+ buf += readlen;
+ len -= readlen;
+
+ ofs ^= DOC_LAYOUT_PAGE_OOB_SIZE;
+ if (ofs == 0)
+ page += 2;
+ if (page > DOC_ADDR_PAGE_MASK) {
+ page = 0;
+ block0 += 2;
+ block1 += 2;
+ }
+
+ /*
+ * There should be a BCH bitstream fixing algorithm here ...
+ * By now, a page read failure is triggered by BCH error
+ */
+ doc_get_hw_bch_syndroms(docg3, syn);
+ eccconf1 = doc_register_readb(docg3, DOC_ECCCONF1);
+
+ doc_dbg("OOB - INFO: %02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
+ oob[0], oob[1], oob[2], oob[3], oob[4],
+ oob[5], oob[6]);
+ doc_dbg("OOB - HAMMING: %02x\n", oob[7]);
+ doc_dbg("OOB - BCH_ECC: %02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
+ oob[8], oob[9], oob[10], oob[11], oob[12],
+ oob[13], oob[14]);
+ doc_dbg("OOB - UNUSED: %02x\n", oob[15]);
+ doc_dbg("ECC checks: ECCConf1=%x\n", eccconf1);
+ doc_dbg("ECC BCH syndrom: %02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
+ syn[0], syn[1], syn[2], syn[3], syn[4], syn[5], syn[6]);
+
+ ret = -EBADMSG;
+ if (block0 >= DOC_LAYOUT_BLOCK_FIRST_DATA) {
+ if (eccconf1 & DOC_ECCCONF1_BCH_SYNDROM_ERR)
+ goto err_in_read;
+ if (is_prot_seq_error(docg3))
+ goto err_in_read;
+ }
+ doc_read_page_finish(docg3);
+ }
+
+ return 0;
+err_in_read:
+ doc_read_page_finish(docg3);
+err:
+ return ret;
+}
+
+/**
+ * doc_read_oob - Read out of band bytes from flash
+ * @mtd: the device
+ * @from: the offset from first block and first page, in bytes, aligned on page
+ * size
+ * @ops: the mtd oob structure
+ *
+ * Reads flash memory OOB area of pages.
+ *
+ * Returns 0 if read successfull, of -EIO, -EINVAL if an error occured
+ */
+static int doc_read_oob(struct mtd_info *mtd, loff_t from,
+ struct mtd_oob_ops *ops)
+{
+ struct docg3 *docg3 = mtd->priv;
+ int block0, block1, page, ofs, ret;
+ u8 *buf = ops->oobbuf;
+ size_t len = ops->ooblen;
+
+ doc_dbg("doc_read_oob(from=%lld, buf=%p, len=%zu)\n", from, buf, len);
+ if (len != DOC_LAYOUT_OOB_SIZE)
+ return -EINVAL;
+
+ switch (ops->mode) {
+ case MTD_OPS_PLACE_OOB:
+ buf += ops->ooboffs;
+ break;
+ default:
+ break;
+ }
+
+ calc_block_sector(from, &block0, &block1, &page, &ofs);
+ if (block1 > docg3->max_block)
+ return -EINVAL;
+
+ ret = doc_read_page_prepare(docg3, block0, block1, page,
+ ofs + DOC_LAYOUT_PAGE_SIZE);
+ if (!ret)
+ ret = doc_read_page_ecc_init(docg3, DOC_LAYOUT_OOB_SIZE);
+ if (!ret)
+ ret = doc_read_page_getbytes(docg3, DOC_LAYOUT_OOB_SIZE,
+ buf, 1);
+ doc_read_page_finish(docg3);
+
+ if (ret > 0)
+ ops->oobretlen = ret;
+ else
+ ops->oobretlen = 0;
+ return (ret > 0) ? 0 : ret;
+}
+
+static int doc_reload_bbt(struct docg3 *docg3)
+{
+ int block = DOC_LAYOUT_BLOCK_BBT;
+ int ret = 0, nbpages, page;
+ u_char *buf = docg3->bbt;
+
+ nbpages = DIV_ROUND_UP(docg3->max_block + 1, 8 * DOC_LAYOUT_PAGE_SIZE);
+ for (page = 0; !ret && (page < nbpages); page++) {
+ ret = doc_read_page_prepare(docg3, block, block + 1,
+ page + DOC_LAYOUT_PAGE_BBT, 0);
+ if (!ret)
+ ret = doc_read_page_ecc_init(docg3,
+ DOC_LAYOUT_PAGE_SIZE);
+ if (!ret)
+ doc_read_page_getbytes(docg3, DOC_LAYOUT_PAGE_SIZE,
+ buf, 1);
+ buf += DOC_LAYOUT_PAGE_SIZE;
+ }
+ doc_read_page_finish(docg3);
+ return ret;
+}
+
+/**
+ * doc_block_isbad - Checks whether a block is good or not
+ * @mtd: the device
+ * @from: the offset to find the correct block
+ *
+ * Returns 1 if block is bad, 0 if block is good
+ */
+static int doc_block_isbad(struct mtd_info *mtd, loff_t from)
+{
+ struct docg3 *docg3 = mtd->priv;
+ int block0, block1, page, ofs, is_good;
+
+ calc_block_sector(from, &block0, &block1, &page, &ofs);
+ doc_dbg("doc_block_isbad(from=%lld) => block=(%d,%d), page=%d, ofs=%d\n",
+ from, block0, block1, page, ofs);
+
+ if (block0 < DOC_LAYOUT_BLOCK_FIRST_DATA)
+ return 0;
+ if (block1 > docg3->max_block)
+ return -EINVAL;
+
+ is_good = docg3->bbt[block0 >> 3] & (1 << (block0 & 0x7));
+ return !is_good;
+}
+
+/**
+ * doc_get_erase_count - Get block erase count
+ * @docg3: the device
+ * @from: the offset in which the block is.
+ *
+ * Get the number of times a block was erased. The number is the maximum of
+ * erase times between first and second plane (which should be equal normally).
+ *
+ * Returns The number of erases, or -EINVAL or -EIO on error.
+ */
+static int doc_get_erase_count(struct docg3 *docg3, loff_t from)
+{
+ u8 buf[DOC_LAYOUT_WEAR_SIZE];
+ int ret, plane1_erase_count, plane2_erase_count;
+ int block0, block1, page, ofs;
+
+ doc_dbg("doc_get_erase_count(from=%lld, buf=%p)\n", from, buf);
+ if (from % DOC_LAYOUT_PAGE_SIZE)
+ return -EINVAL;
+ calc_block_sector(from, &block0, &block1, &page, &ofs);
+ if (block1 > docg3->max_block)
+ return -EINVAL;
+
+ ret = doc_reset_seq(docg3);
+ if (!ret)
+ ret = doc_read_page_prepare(docg3, block0, block1, page,
+ ofs + DOC_LAYOUT_WEAR_OFFSET);
+ if (!ret)
+ ret = doc_read_page_getbytes(docg3, DOC_LAYOUT_WEAR_SIZE,
+ buf, 1);
+ doc_read_page_finish(docg3);
+
+ if (ret || (buf[0] != DOC_ERASE_MARK) || (buf[2] != DOC_ERASE_MARK))
+ return -EIO;
+ plane1_erase_count = (u8)(~buf[1]) | ((u8)(~buf[4]) << 8)
+ | ((u8)(~buf[5]) << 16);
+ plane2_erase_count = (u8)(~buf[3]) | ((u8)(~buf[6]) << 8)
+ | ((u8)(~buf[7]) << 16);
+
+ return max(plane1_erase_count, plane2_erase_count);
+}
+
+/*
+ * Debug sysfs entries
+ */
+static int dbg_flashctrl_show(struct seq_file *s, void *p)
+{
+ struct docg3 *docg3 = (struct docg3 *)s->private;
+
+ int pos = 0;
+ u8 fctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
+
+ pos += seq_printf(s,
+ "FlashControl : 0x%02x (%s,CE# %s,%s,%s,flash %s)\n",
+ fctrl,
+ fctrl & DOC_CTRL_VIOLATION ? "protocol violation" : "-",
+ fctrl & DOC_CTRL_CE ? "active" : "inactive",
+ fctrl & DOC_CTRL_PROTECTION_ERROR ? "protection error" : "-",
+ fctrl & DOC_CTRL_SEQUENCE_ERROR ? "sequence error" : "-",
+ fctrl & DOC_CTRL_FLASHREADY ? "ready" : "not ready");
+ return pos;
+}
+DEBUGFS_RO_ATTR(flashcontrol, dbg_flashctrl_show);
+
+static int dbg_asicmode_show(struct seq_file *s, void *p)
+{
+ struct docg3 *docg3 = (struct docg3 *)s->private;
+
+ int pos = 0;
+ int pctrl = doc_register_readb(docg3, DOC_ASICMODE);
+ int mode = pctrl & 0x03;
+
+ pos += seq_printf(s,
+ "%04x : RAM_WE=%d,RSTIN_RESET=%d,BDETCT_RESET=%d,WRITE_ENABLE=%d,POWERDOWN=%d,MODE=%d%d (",
+ pctrl,
+ pctrl & DOC_ASICMODE_RAM_WE ? 1 : 0,
+ pctrl & DOC_ASICMODE_RSTIN_RESET ? 1 : 0,
+ pctrl & DOC_ASICMODE_BDETCT_RESET ? 1 : 0,
+ pctrl & DOC_ASICMODE_MDWREN ? 1 : 0,
+ pctrl & DOC_ASICMODE_POWERDOWN ? 1 : 0,
+ mode >> 1, mode & 0x1);
+
+ switch (mode) {
+ case DOC_ASICMODE_RESET:
+ pos += seq_printf(s, "reset");
+ break;
+ case DOC_ASICMODE_NORMAL:
+ pos += seq_printf(s, "normal");
+ break;
+ case DOC_ASICMODE_POWERDOWN:
+ pos += seq_printf(s, "powerdown");
+ break;
+ }
+ pos += seq_printf(s, ")\n");
+ return pos;
+}
+DEBUGFS_RO_ATTR(asic_mode, dbg_asicmode_show);
+
+static int dbg_device_id_show(struct seq_file *s, void *p)
+{
+ struct docg3 *docg3 = (struct docg3 *)s->private;
+ int pos = 0;
+ int id = doc_register_readb(docg3, DOC_DEVICESELECT);
+
+ pos += seq_printf(s, "DeviceId = %d\n", id);
+ return pos;
+}
+DEBUGFS_RO_ATTR(device_id, dbg_device_id_show);
+
+static int dbg_protection_show(struct seq_file *s, void *p)
+{
+ struct docg3 *docg3 = (struct docg3 *)s->private;
+ int pos = 0;
+ int protect = doc_register_readb(docg3, DOC_PROTECTION);
+ int dps0 = doc_register_readb(docg3, DOC_DPS0_STATUS);
+ int dps0_low = doc_register_readb(docg3, DOC_DPS0_ADDRLOW);
+ int dps0_high = doc_register_readb(docg3, DOC_DPS0_ADDRHIGH);
+ int dps1 = doc_register_readb(docg3, DOC_DPS1_STATUS);
+ int dps1_low = doc_register_readb(docg3, DOC_DPS1_ADDRLOW);
+ int dps1_high = doc_register_readb(docg3, DOC_DPS1_ADDRHIGH);
+
+ pos += seq_printf(s, "Protection = 0x%02x (",
+ protect);
+ if (protect & DOC_PROTECT_FOUNDRY_OTP_LOCK)
+ pos += seq_printf(s, "FOUNDRY_OTP_LOCK,");
+ if (protect & DOC_PROTECT_CUSTOMER_OTP_LOCK)
+ pos += seq_printf(s, "CUSTOMER_OTP_LOCK,");
+ if (protect & DOC_PROTECT_LOCK_INPUT)
+ pos += seq_printf(s, "LOCK_INPUT,");
+ if (protect & DOC_PROTECT_STICKY_LOCK)
+ pos += seq_printf(s, "STICKY_LOCK,");
+ if (protect & DOC_PROTECT_PROTECTION_ENABLED)
+ pos += seq_printf(s, "PROTECTION ON,");
+ if (protect & DOC_PROTECT_IPL_DOWNLOAD_LOCK)
+ pos += seq_printf(s, "IPL_DOWNLOAD_LOCK,");
+ if (protect & DOC_PROTECT_PROTECTION_ERROR)
+ pos += seq_printf(s, "PROTECT_ERR,");
+ else
+ pos += seq_printf(s, "NO_PROTECT_ERR");
+ pos += seq_printf(s, ")\n");
+
+ pos += seq_printf(s, "DPS0 = 0x%02x : "
+ "Protected area [0x%x - 0x%x] : OTP=%d, READ=%d, "
+ "WRITE=%d, HW_LOCK=%d, KEY_OK=%d\n",
+ dps0, dps0_low, dps0_high,
+ !!(dps0 & DOC_DPS_OTP_PROTECTED),
+ !!(dps0 & DOC_DPS_READ_PROTECTED),
+ !!(dps0 & DOC_DPS_WRITE_PROTECTED),
+ !!(dps0 & DOC_DPS_HW_LOCK_ENABLED),
+ !!(dps0 & DOC_DPS_KEY_OK));
+ pos += seq_printf(s, "DPS1 = 0x%02x : "
+ "Protected area [0x%x - 0x%x] : OTP=%d, READ=%d, "
+ "WRITE=%d, HW_LOCK=%d, KEY_OK=%d\n",
+ dps1, dps1_low, dps1_high,
+ !!(dps1 & DOC_DPS_OTP_PROTECTED),
+ !!(dps1 & DOC_DPS_READ_PROTECTED),
+ !!(dps1 & DOC_DPS_WRITE_PROTECTED),
+ !!(dps1 & DOC_DPS_HW_LOCK_ENABLED),
+ !!(dps1 & DOC_DPS_KEY_OK));
+ return pos;
+}
+DEBUGFS_RO_ATTR(protection, dbg_protection_show);
+
+static int __init doc_dbg_register(struct docg3 *docg3)
+{
+ struct dentry *root, *entry;
+
+ root = debugfs_create_dir("docg3", NULL);
+ if (!root)
+ return -ENOMEM;
+
+ entry = debugfs_create_file("flashcontrol", S_IRUSR, root, docg3,
+ &flashcontrol_fops);
+ if (entry)
+ entry = debugfs_create_file("asic_mode", S_IRUSR, root,
+ docg3, &asic_mode_fops);
+ if (entry)
+ entry = debugfs_create_file("device_id", S_IRUSR, root,
+ docg3, &device_id_fops);
+ if (entry)
+ entry = debugfs_create_file("protection", S_IRUSR, root,
+ docg3, &protection_fops);
+ if (entry) {
+ docg3->debugfs_root = root;
+ return 0;
+ } else {
+ debugfs_remove_recursive(root);
+ return -ENOMEM;
+ }
+}
+
+static void __exit doc_dbg_unregister(struct docg3 *docg3)
+{
+ debugfs_remove_recursive(docg3->debugfs_root);
+}
+
+/**
+ * doc_set_driver_info - Fill the mtd_info structure and docg3 structure
+ * @chip_id: The chip ID of the supported chip
+ * @mtd: The structure to fill
+ */
+static void __init doc_set_driver_info(int chip_id, struct mtd_info *mtd)
+{
+ struct docg3 *docg3 = mtd->priv;
+ int cfg;
+
+ cfg = doc_register_readb(docg3, DOC_CONFIGURATION);
+ docg3->if_cfg = (cfg & DOC_CONF_IF_CFG ? 1 : 0);
+
+ switch (chip_id) {
+ case DOC_CHIPID_G3:
+ mtd->name = "DiskOnChip G3";
+ docg3->max_block = 2047;
+ break;
+ }
+ mtd->type = MTD_NANDFLASH;
+ /*
+ * Once write methods are added, the correct flags will be set.
+ * mtd->flags = MTD_CAP_NANDFLASH;
+ */
+ mtd->flags = MTD_CAP_ROM;
+ mtd->size = (docg3->max_block + 1) * DOC_LAYOUT_BLOCK_SIZE;
+ mtd->erasesize = DOC_LAYOUT_BLOCK_SIZE * DOC_LAYOUT_NBPLANES;
+ mtd->writesize = DOC_LAYOUT_PAGE_SIZE;
+ mtd->oobsize = DOC_LAYOUT_OOB_SIZE;
+ mtd->owner = THIS_MODULE;
+ mtd->erase = NULL;
+ mtd->point = NULL;
+ mtd->unpoint = NULL;
+ mtd->read = doc_read;
+ mtd->write = NULL;
+ mtd->read_oob = doc_read_oob;
+ mtd->write_oob = NULL;
+ mtd->sync = NULL;
+ mtd->block_isbad = doc_block_isbad;
+}
+
+/**
+ * doc_probe - Probe the IO space for a DiskOnChip G3 chip
+ * @pdev: platform device
+ *
+ * Probes for a G3 chip at the specified IO space in the platform data
+ * ressources.
+ *
+ * Returns 0 on success, -ENOMEM, -ENXIO on error
+ */
+static int __init docg3_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct docg3 *docg3;
+ struct mtd_info *mtd;
+ struct resource *ress;
+ int ret, bbt_nbpages;
+ u16 chip_id, chip_id_inv;
+
+ ret = -ENOMEM;
+ docg3 = kzalloc(sizeof(struct docg3), GFP_KERNEL);
+ if (!docg3)
+ goto nomem1;
+ mtd = kzalloc(sizeof(struct mtd_info), GFP_KERNEL);
+ if (!mtd)
+ goto nomem2;
+ mtd->priv = docg3;
+
+ ret = -ENXIO;
+ ress = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!ress) {
+ dev_err(dev, "No I/O memory resource defined\n");
+ goto noress;
+ }
+ docg3->base = ioremap(ress->start, DOC_IOSPACE_SIZE);
+
+ docg3->dev = &pdev->dev;
+ docg3->device_id = 0;
+ doc_set_device_id(docg3, docg3->device_id);
+ doc_set_asic_mode(docg3, DOC_ASICMODE_RESET);
+ doc_set_asic_mode(docg3, DOC_ASICMODE_NORMAL);
+
+ chip_id = doc_register_readw(docg3, DOC_CHIPID);
+ chip_id_inv = doc_register_readw(docg3, DOC_CHIPID_INV);
+
+ ret = -ENODEV;
+ if (chip_id != (u16)(~chip_id_inv)) {
+ doc_info("No device found at IO addr %p\n",
+ (void *)ress->start);
+ goto nochipfound;
+ }
+
+ switch (chip_id) {
+ case DOC_CHIPID_G3:
+ doc_info("Found a G3 DiskOnChip at addr %p\n",
+ (void *)ress->start);
+ break;
+ default:
+ doc_err("Chip id %04x is not a DiskOnChip G3 chip\n", chip_id);
+ goto nochipfound;
+ }
+
+ doc_set_driver_info(chip_id, mtd);
+ platform_set_drvdata(pdev, mtd);
+
+ ret = -ENOMEM;
+ bbt_nbpages = DIV_ROUND_UP(docg3->max_block + 1,
+ 8 * DOC_LAYOUT_PAGE_SIZE);
+ docg3->bbt = kzalloc(bbt_nbpages * DOC_LAYOUT_PAGE_SIZE, GFP_KERNEL);
+ if (!docg3->bbt)
+ goto nochipfound;
+ doc_reload_bbt(docg3);
+
+ ret = mtd_device_parse_register(mtd, part_probes,
+ NULL, NULL, 0);
+ if (ret)
+ goto register_error;
+
+ doc_dbg_register(docg3);
+ return 0;
+
+register_error:
+ kfree(docg3->bbt);
+nochipfound:
+ iounmap(docg3->base);
+noress:
+ kfree(mtd);
+nomem2:
+ kfree(docg3);
+nomem1:
+ return ret;
+}
+
+/**
+ * docg3_release - Release the driver
+ * @pdev: the platform device
+ *
+ * Returns 0
+ */
+static int __exit docg3_release(struct platform_device *pdev)
+{
+ struct mtd_info *mtd = platform_get_drvdata(pdev);
+ struct docg3 *docg3 = mtd->priv;
+
+ doc_dbg_unregister(docg3);
+ mtd_device_unregister(mtd);
+ iounmap(docg3->base);
+ kfree(docg3->bbt);
+ kfree(docg3);
+ kfree(mtd);
+ return 0;
+}
+
+static struct platform_driver g3_driver = {
+ .driver = {
+ .name = "docg3",
+ .owner = THIS_MODULE,
+ },
+ .remove = __exit_p(docg3_release),
+};
+
+static int __init docg3_init(void)
+{
+ return platform_driver_probe(&g3_driver, docg3_probe);
+}
+module_init(docg3_init);
+
+
+static void __exit docg3_exit(void)
+{
+ platform_driver_unregister(&g3_driver);
+}
+module_exit(docg3_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
+MODULE_DESCRIPTION("MTD driver for DiskOnChip G3");
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