--- /dev/null
+/*
+ * YAFFS: Yet another FFS. A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002 Aleph One Ltd.
+ * for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *
+ * This version hacked for emulating 2kpage NAND for YAFFS2 testing.
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/fs.h>
+#include <linux/proc_fs.h>
+#include <linux/pagemap.h>
+#include <linux/mtd/mtd.h>
+#include <linux/interrupt.h>
+#include <linux/string.h>
+#include <linux/locks.h>
+
+#include <asm/uaccess.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/nand.h>
+
+#define T(f,x) printk x
+#define ALLOCATE(x) kmalloc(x,GFP_KERNEL)
+#define FREE(x) kfree(x)
+
+
+
+
+
+#define EM_SIZE_IN_MEG 4
+#define PAGE_DATA_SIZE (2048)
+#define PAGE_SPARE_SIZE (64)
+#define PAGES_PER_BLOCK (64)
+#define NAND_SHIFT (11) // Shifter for 2k
+
+
+#define EM_SIZE_IN_BYTES (EM_SIZE_IN_MEG * (1<<20))
+
+#define PAGE_TOTAL_SIZE (PAGE_DATA_SIZE+PAGE_SPARE_SIZE)
+
+#define BLOCK_TOTAL_SIZE (PAGES_PER_BLOCK * PAGE_TOTAL_SIZE)
+
+#define BLOCKS_PER_MEG ((1<<20)/(PAGES_PER_BLOCK * PAGE_DATA_SIZE))
+
+
+static struct mtd_info nandemul2k_mtd;
+
+typedef struct
+{
+ __u8 data[PAGE_TOTAL_SIZE]; // Data + spare
+ int empty; // is this empty?
+} nandemul_Page;
+
+
+typedef struct
+{
+ nandemul_Page *page[PAGES_PER_BLOCK];
+ int damaged;
+} nandemul_Block;
+
+
+
+typedef struct
+{
+ nandemul_Block**block;
+ int nBlocks;
+} nandemul_Device;
+
+static nandemul_Device ned;
+
+static int sizeInMB = EM_SIZE_IN_MEG;
+
+
+static void nandemul_yield(int n)
+{
+#ifdef __KERNEL__
+ if(n > 0) schedule_timeout(n);
+#endif
+
+}
+
+
+static void nandemul2k_Read(void *buffer, int page, int start, int nBytes)
+{
+ int pg = page%PAGES_PER_BLOCK;
+ int blk = page/PAGES_PER_BLOCK;
+ if(buffer && nBytes > 0)
+ {
+ memcpy(buffer,&ned.block[blk]->page[pg]->data[start],nBytes);
+ }
+
+}
+
+static void nandemul2k_Program(const void *buffer, int page, int start, int nBytes)
+{
+ int pg = page%PAGES_PER_BLOCK;
+ int blk = page/PAGES_PER_BLOCK;
+ __u8 *p;
+ __u8 *b = (__u8 *)buffer;
+
+ p = &ned.block[blk]->page[pg]->data[start];
+
+ while(buffer && nBytes>0)
+ {
+ *p = *p & *b;
+ p++;
+ b++;
+ nBytes--;
+ }
+}
+
+static void nandemul2k_DoErase(int blockNumber)
+{
+ int i;
+
+ nandemul_Block *blk;
+
+ if(blockNumber < 0 || blockNumber >= ned.nBlocks)
+ {
+ return;
+ }
+
+ blk = ned.block[blockNumber];
+
+ for(i = 0; i < PAGES_PER_BLOCK; i++)
+ {
+ memset(blk->page[i],0xff,sizeof(nandemul_Page));
+ blk->page[i]->empty = 1;
+ }
+ nandemul_yield(2);
+}
+
+
+static int nandemul2k_CalcNBlocks(void)
+{
+ return EM_SIZE_IN_MEG * BLOCKS_PER_MEG;
+}
+
+
+
+static int CheckInit(void)
+{
+ static int initialised = 0;
+
+ int i,j;
+
+ int fail = 0;
+ int nBlocks;
+
+ int nAllocated = 0;
+
+ if(initialised)
+ {
+ return 0;
+ }
+
+
+ ned.nBlocks = nBlocks = nandemul2k_CalcNBlocks();
+
+
+ ned.block = ALLOCATE(sizeof(nandemul_Block*) * nBlocks );
+
+ if(!ned.block) return ENOMEM;
+
+
+
+
+
+ for(i=fail=0; i <nBlocks; i++)
+ {
+
+ nandemul_Block *blk;
+
+ if(!(blk = ned.block[i] = ALLOCATE(sizeof(nandemul_Block))))
+ {
+ fail = 1;
+ }
+ else
+ {
+ for(j = 0; j < PAGES_PER_BLOCK; j++)
+ {
+ if((blk->page[j] = ALLOCATE(sizeof(nandemul_Page))) == 0)
+ {
+ fail = 1;
+ }
+ }
+ nandemul2k_DoErase(i);
+ ned.block[i]->damaged = 0;
+ nAllocated++;
+ }
+ }
+
+ if(fail)
+ {
+ //Todo thump pages
+
+ for(i = 0; i < nAllocated; i++)
+ {
+ FREE(ned.block[i]);
+ }
+ FREE(ned.block);
+
+ return ENOMEM;
+ }
+
+ ned.nBlocks = nBlocks;
+
+ initialised = 1;
+
+ return 1;
+}
+
+
+
+static void nandemul2k_CleanUp(void)
+{
+ int i,j;
+
+ for(i = 0; i < ned.nBlocks; i++)
+ {
+ for(j = 0; j < PAGES_PER_BLOCK; j++)
+ {
+ FREE(ned.block[i]->page[j]);
+ }
+ FREE(ned.block[i]);
+
+ }
+ FREE(ned.block);
+ ned.block = 0;
+}
+
+int nandemul2k_GetBytesPerChunk(void) { return PAGE_DATA_SIZE;}
+
+int nandemul2k_GetChunksPerBlock(void) { return PAGES_PER_BLOCK; }
+int nandemul2k_GetNumberOfBlocks(void) {return nandemul2k_CalcNBlocks();}
+
+
+
+int nandemul2k_ReadId(__u8 *vendorId, __u8 *deviceId)
+{
+ *vendorId = 'Y';
+ *deviceId = '2';
+
+ return 1;
+}
+
+
+int nandemul2k_ReadStatus(__u8 *status)
+{
+ *status = 0;
+ return 1;
+}
+
+
+#ifdef CONFIG_MTD_NAND_ECC
+#include <linux/mtd/nand_ecc.h>
+#endif
+
+/*
+ * NAND low-level MTD interface functions
+ */
+static int nand_read (struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, u_char *buf);
+static int nand_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, u_char *buf, u_char *oob_buf, struct nand_oobinfo *dummy);
+static int nand_read_oob (struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, u_char *buf);
+static int nand_write (struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const u_char *buf);
+static int nand_write_ecc (struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const u_char *buf,
+ const u_char *oob_buf, struct nand_oobinfo *dummy);
+static int nand_write_oob (struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const u_char *buf);
+static int nand_writev (struct mtd_info *mtd, const struct iovec *vecs,
+ unsigned long count, loff_t to, size_t *retlen);
+static int nand_erase (struct mtd_info *mtd, struct erase_info *instr);
+static void nand_sync (struct mtd_info *mtd);
+
+
+
+/*
+ * NAND read
+ */
+static int nand_read (struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, u_char *buf)
+{
+ return nand_read_ecc (mtd, from, len, retlen, buf, NULL,NULL);
+}
+
+
+/*
+ * NAND read with ECC
+ */
+static int nand_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, u_char *buf, u_char *oob_buf,struct nand_oobinfo *oobsel)
+{
+ int start, page;
+ int n = len;
+ int nToCopy;
+
+
+
+ /* Do not allow reads past end of device */
+ if ((from + len) > mtd->size) {
+ *retlen = 0;
+ return -EINVAL;
+ }
+
+
+ /* Initialize return value */
+ *retlen = 0;
+
+ while(n > 0)
+ {
+
+ /* First we calculate the starting page */
+ page = from >> NAND_SHIFT;
+
+ /* Get raw starting column */
+
+ start = from & (mtd->oobblock-1);
+
+ // OK now check for the curveball where the start and end are in
+ // the same page
+ if((start + n) < mtd->oobblock)
+ {
+ nToCopy = n;
+ }
+ else
+ {
+ nToCopy = mtd->oobblock - start;
+ }
+
+ nandemul2k_Read(buf, page, start, nToCopy);
+ nandemul2k_Read(oob_buf,page,PAGE_DATA_SIZE,PAGE_SPARE_SIZE);
+
+ n -= nToCopy;
+ from += nToCopy;
+ buf += nToCopy;
+ if(oob_buf) oob_buf += PAGE_SPARE_SIZE;
+ *retlen += nToCopy;
+
+ }
+
+
+ return 0;
+}
+
+/*
+ * NAND read out-of-band
+ */
+static int nand_read_oob (struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, u_char *buf)
+{
+ int col, page;
+
+ T(0,("nand_read_oob: from = 0x%08x, buf = 0x%08x, len = %i\n", (unsigned int) from, (unsigned int) buf,
+ (int) len));
+
+ /* Shift to get page */
+ page = ((int) from) >> NAND_SHIFT;
+
+ /* Mask to get column */
+ col = from & 0x0f;
+
+ /* Initialize return length value */
+ *retlen = 0;
+
+ /* Do not allow reads past end of device */
+ if ((from + len) > mtd->size) {
+ T(0,
+ ("nand_read_oob: Attempt read beyond end of device\n"));
+ *retlen = 0;
+ return -EINVAL;
+ }
+
+ nandemul2k_Read(buf,page,PAGE_DATA_SIZE + col,len);
+
+ /* Return happy */
+ *retlen = len;
+ return 0;
+}
+
+/*
+ * NAND write
+ */
+static int nand_write (struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const u_char *buf)
+{
+ return nand_write_ecc (mtd, to, len, retlen, buf, NULL,NULL);
+}
+
+/*
+ * NAND write with ECC
+ */
+static int nand_write_ecc (struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const u_char *buf,
+ const u_char *oob_buf, struct nand_oobinfo *dummy)
+{
+
+ int start, page;
+ int n = len;
+ int nToCopy;
+
+
+
+ /* Do not allow reads past end of device */
+ if ((to + len) > mtd->size) {
+ *retlen = 0;
+ return -EINVAL;
+ }
+
+
+ /* Initialize return value */
+ *retlen = 0;
+
+ while(n > 0)
+ {
+
+ /* First we calculate the starting page */
+ page = to >> NAND_SHIFT;
+
+ /* Get raw starting column */
+
+ start = to & (mtd->oobblock - 1);
+
+ // OK now check for the curveball where the start and end are in
+ // the same page
+ if((start + n) < mtd->oobblock)
+ {
+ nToCopy = n;
+ }
+ else
+ {
+ nToCopy = mtd->oobblock - start;
+ }
+
+ nandemul2k_Program(buf, page, start, nToCopy);
+ nandemul2k_Program(oob_buf, page, PAGE_DATA_SIZE, PAGE_SPARE_SIZE);
+
+ n -= nToCopy;
+ to += nToCopy;
+ buf += nToCopy;
+ if(oob_buf) oob_buf += PAGE_SPARE_SIZE;
+ *retlen += nToCopy;
+
+ }
+
+
+ return 0;
+}
+
+/*
+ * NAND write out-of-band
+ */
+static int nand_write_oob (struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const u_char *buf)
+{
+ int col, page;
+
+
+ T(0,(
+ "nand_read_oob: to = 0x%08x, len = %i\n", (unsigned int) to,
+ (int) len));
+
+ /* Shift to get page */
+ page = ((int) to) >> NAND_SHIFT;
+
+ /* Mask to get column */
+ col = to & 0x0f;
+
+ /* Initialize return length value */
+ *retlen = 0;
+
+ /* Do not allow reads past end of device */
+ if ((to + len) > mtd->size) {
+ T(0,(
+ "nand_read_oob: Attempt read beyond end of device\n"));
+ *retlen = 0;
+ return -EINVAL;
+ }
+
+ nandemul2k_Program(buf,page,512 + col,len);
+
+ /* Return happy */
+ *retlen = len;
+ return 0;
+
+}
+
+/*
+ * NAND write with iovec
+ */
+static int nand_writev (struct mtd_info *mtd, const struct iovec *vecs,
+ unsigned long count, loff_t to, size_t *retlen)
+{
+ return -EINVAL;
+}
+
+/*
+ * NAND erase a block
+ */
+static int nand_erase (struct mtd_info *mtd, struct erase_info *instr)
+{
+ int i, nBlocks,block;
+
+ T(0,(
+ "nand_erase: start = 0x%08x, len = %i\n",
+ (unsigned int) instr->addr, (unsigned int) instr->len));
+
+ /* Start address must align on block boundary */
+ if (instr->addr & (mtd->erasesize - 1)) {
+ T(0,(
+ "nand_erase: Unaligned address\n"));
+ return -EINVAL;
+ }
+
+ /* Length must align on block boundary */
+ if (instr->len & (mtd->erasesize - 1)) {
+ T(0,(
+ "nand_erase: Length not block aligned\n"));
+ return -EINVAL;
+ }
+
+ /* Do not allow erase past end of device */
+ if ((instr->len + instr->addr) > mtd->size) {
+ T(0,(
+ "nand_erase: Erase past end of device\n"));
+ return -EINVAL;
+ }
+
+ nBlocks = instr->len >> (NAND_SHIFT + 5);
+ block = instr->addr >> (NAND_SHIFT + 5);
+
+ for(i = 0; i < nBlocks; i++)
+ {
+ nandemul2k_DoErase(block);
+ block++;
+ }
+
+
+
+ return 0;
+
+
+}
+
+
+int nand_block_isbad(struct mtd_info *mtd,int blockNo)
+{
+ return 0;
+}
+
+int nand_block_markbad(struct mtd_info *mtd, int blockNo)
+{
+ return 0;
+}
+
+
+/*
+ * NAND sync
+ */
+static void nand_sync (struct mtd_info *mtd)
+{
+ T(0,("nand_sync: called\n"));
+
+}
+
+/*
+ * Scan for the NAND device
+ */
+int nand_scan (struct mtd_info *mtd,int nchips)
+{
+ mtd->oobblock = PAGE_DATA_SIZE;
+ mtd->oobsize = PAGE_SPARE_SIZE;
+ mtd->erasesize = PAGE_DATA_SIZE * PAGES_PER_BLOCK;
+ mtd->size = sizeInMB * 1024*1024;
+
+
+
+ /* Fill in remaining MTD driver data */
+ mtd->type = MTD_NANDFLASH;
+ mtd->flags = MTD_CAP_NANDFLASH;
+ mtd->owner = THIS_MODULE;
+ mtd->ecctype = MTD_ECC_NONE;
+ mtd->erase = nand_erase;
+ mtd->point = NULL;
+ mtd->unpoint = NULL;
+ mtd->read = nand_read;
+ mtd->write = nand_write;
+ mtd->read_ecc = nand_read_ecc;
+ mtd->write_ecc = nand_write_ecc;
+ mtd->read_oob = nand_read_oob;
+ mtd->write_oob = nand_write_oob;
+ mtd->block_isbad = nand_block_isbad;
+ mtd->block_markbad = nand_block_markbad;
+ mtd->readv = NULL;
+ mtd->writev = nand_writev;
+ mtd->sync = nand_sync;
+ mtd->lock = NULL;
+ mtd->unlock = NULL;
+ mtd->suspend = NULL;
+ mtd->resume = NULL;
+
+ /* Return happy */
+ return 0;
+}
+
+#if 0
+#ifdef MODULE
+MODULE_PARM(sizeInMB, "i");
+
+__setup("sizeInMB=",sizeInMB);
+#endif
+#endif
+
+/*
+ * Define partitions for flash devices
+ */
+
+static struct mtd_partition nandemul2k_partition[] =
+{
+ { name: "NANDemul partition 1",
+ offset: 0,
+ size: 0 },
+};
+
+static int nPartitions = sizeof(nandemul2k_partition)/sizeof(nandemul2k_partition[0]);
+
+/*
+ * Main initialization routine
+ */
+int __init nandemul2k_init (void)
+{
+
+ // Do the nand init
+
+ CheckInit();
+
+ nand_scan(&nandemul2k_mtd,1);
+
+ // Build the partition table
+
+ nandemul2k_partition[0].size = sizeInMB * 1024 * 1024;
+
+ // Register the partition
+ add_mtd_partitions(&nandemul2k_mtd,nandemul2k_partition,nPartitions);
+
+ return 0;
+
+}
+
+module_init(nandemul2k_init);
+
+/*
+ * Clean up routine
+ */
+#ifdef MODULE
+static void __exit nandemul2k_cleanup (void)
+{
+
+ nandemul2k_CleanUp();
+
+ /* Unregister partitions */
+ del_mtd_partitions(&nandemul2k_mtd);
+
+ /* Unregister the device */
+ del_mtd_device (&nandemul2k_mtd);
+
+}
+module_exit(nandemul2k_cleanup);
+#endif
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Charles Manning <manningc@aleph1.co.uk>");
+MODULE_DESCRIPTION("2k Page/128k Block NAND emulated in RAM");
+
+
+
+
projects / yaffs2.git / blobdiff