[xburst] jz4740_nand:
authorLars-Peter Clausen <lars@metafoo.de>
Fri, 26 Feb 2010 18:09:12 +0000 (18:09 +0000)
committerLars-Peter Clausen <lars@metafoo.de>
Fri, 26 Feb 2010 18:09:12 +0000 (18:09 +0000)
* Use NAND_ECC_HW_OOB_FIRST mode instead of a patched NAND_ECC_HW
* Fix subpage writing
* speed up reading

SVN-Revision: 19875

target/linux/xburst/files-2.6.32/drivers/mtd/nand/jz4740_nand.c
target/linux/xburst/patches-2.6.32/050-nand.patch

index d1e3818..abe0caa 100644 (file)
@@ -60,6 +60,7 @@ struct jz_nand {
        struct resource *mem;
 
        struct jz_nand_platform_data *pdata;
+       bool is_reading;
 };
 
 static inline struct jz_nand *mtd_to_jz_nand(struct mtd_info *mtd)
@@ -115,9 +116,11 @@ static void jz_nand_hwctl(struct mtd_info *mtd, int mode)
        switch(mode) {
        case NAND_ECC_READ:
                reg &= ~JZ_NAND_ECC_CTRL_ENCODING;
+               nand->is_reading = true;
                break;
        case NAND_ECC_WRITE:
                reg |= JZ_NAND_ECC_CTRL_ENCODING;
+               nand->is_reading = false;
                break;
        default:
                break;
@@ -126,12 +129,17 @@ static void jz_nand_hwctl(struct mtd_info *mtd, int mode)
        writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
 }
 
+
 static int jz_nand_calculate_ecc_rs(struct mtd_info* mtd, const uint8_t* dat,
                                        uint8_t *ecc_code)
 {
        struct jz_nand *nand = mtd_to_jz_nand(mtd);
        uint32_t reg, status;
        int i;
+       static uint8_t all_ff_ecc[] = {0xcd, 0x9d, 0x90, 0x58, 0xf4, 0x8b, 0xff, 0xb7, 0x6f};
+
+       if (nand->is_reading)
+               return 0;
 
        do {
                status = readl(nand->base + JZ_REG_NAND_IRQ_STAT);
@@ -145,27 +153,36 @@ static int jz_nand_calculate_ecc_rs(struct mtd_info* mtd, const uint8_t* dat,
                ecc_code[i] = readb(nand->base + JZ_REG_NAND_PAR0 + i);
        }
 
+       /* If the written data is completly 0xff, we also want to write 0xff as
+        * ecc, otherwise we will get in trouble when doing subpage writes. */
+       if (memcmp(ecc_code, all_ff_ecc, 9) == 0) {
+               memset(ecc_code, 0xff, 9);
+       }
+
        return 0;
 }
 
+/*#define printkd printk*/
+#define printkd(...)
+
 static void correct_data(uint8_t *dat, int index, int mask)
 {
        int offset = index & 0x7;
        uint16_t data;
-       printk("correct: ");
+       printkd("correct: ");
 
        index += (index >> 3);
 
        data = dat[index];
        data |= dat[index+1] << 8;
 
-       printk("0x%x -> ", data);
+       printkd("0x%x -> ", data);
 
        mask ^= (data >> offset) & 0x1ff;
        data &= ~(0x1ff << offset);
        data |= (mask << offset);
 
-       printk("0x%x\n", data);
+       printkd("0x%x\n", data);
 
        dat[index] = data & 0xff;
        dat[index+1] = (data >> 8) & 0xff;
@@ -177,18 +194,24 @@ static int jz_nand_correct_ecc_rs(struct mtd_info* mtd, uint8_t *dat,
        struct jz_nand *nand = mtd_to_jz_nand(mtd);
        int i, error_count, index;
        uint32_t reg, status, error;
+       uint32_t t;
 
-       for(i = 0; i < 9; ++i) {
-               if (read_ecc[i] != 0xff)
-                       break;
-       }
-       if (i == 9) {
-               for (i = 0; i < nand->chip.ecc.size; ++i) {
-                       if (dat[i] != 0xff)
-                               break;
+       t = read_ecc[0];
+
+       if (t == 0xff) {
+               for (i = 1; i < 9; ++i)
+                       t &= read_ecc[i];
+
+               t &= dat[0];
+               t &= dat[nand->chip.ecc.size / 2];
+               t &= dat[nand->chip.ecc.size - 1];
+
+               if (t == 0xff) {
+                       for (i = 1; i < nand->chip.ecc.size - 1; ++i)
+                               t &= dat[i];
+                       if (t == 0xff)
+                               return 0;
                }
-               if (i == nand->chip.ecc.size)
-                       return 0;
        }
 
        for(i = 0; i < 9; ++i)
@@ -208,20 +231,20 @@ static int jz_nand_correct_ecc_rs(struct mtd_info* mtd, uint8_t *dat,
 
        if (status & JZ_NAND_STATUS_ERROR) {
                if (status & JZ_NAND_STATUS_UNCOR_ERROR) {
-                       printk("uncorrectable ecc:");
+                       printkd("uncorrectable ecc:");
                        for(i = 0; i < 9; ++i)
-                               printk(" 0x%x", read_ecc[i]);
-                       printk("\n");
-                       printk("uncorrectable data:");
+                               printkd(" 0x%x", read_ecc[i]);
+                       printkd("\n");
+                       printkd("uncorrectable data:");
                        for(i = 0; i < 32; ++i)
-                               printk(" 0x%x", dat[i]);
-                       printk("\n");
+                               printkd(" 0x%x", dat[i]);
+                       printkd("\n");
                        return -1;
                }
 
                error_count = (status & JZ_NAND_STATUS_ERR_COUNT) >> 29;
 
-               printk("error_count: %d %x\n", error_count, status);
+               printkd("error_count: %d %x\n", error_count, status);
 
                for(i = 0; i < error_count; ++i) {
                        error = readl(nand->base + JZ_REG_NAND_ERR(i));
@@ -304,7 +327,7 @@ static int __devinit jz_nand_probe(struct platform_device *pdev)
 
        chip->ecc.calculate     = jz_nand_calculate_ecc_rs;
        chip->ecc.correct       = jz_nand_correct_ecc_rs;
-       chip->ecc.mode          = NAND_ECC_HW;
+       chip->ecc.mode          = NAND_ECC_HW_OOB_FIRST;
        chip->ecc.size          = 512;
        chip->ecc.bytes         = 9;
        if (pdata)
index e803a21..bdb1df8 100644 (file)
@@ -31,49 +31,4 @@ Subject: [PATCH] /opt/Projects/openwrt/target/linux/xburst/patches-2.6.31/050-na
 +obj-$(CONFIG_MTD_NAND_JZ4740)         += jz4740_nand.o
  
  nand-objs := nand_base.o nand_bbt.o
---- a/drivers/mtd/nand/nand_base.c
-+++ b/drivers/mtd/nand/nand_base.c
-@@ -956,29 +956,22 @@ static int nand_read_page_hwecc(struct m
-       uint8_t *ecc_calc = chip->buffers->ecccalc;
-       uint8_t *ecc_code = chip->buffers->ecccode;
-       uint32_t *eccpos = chip->ecc.layout->eccpos;
--
--      for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
--              chip->ecc.hwctl(mtd, NAND_ECC_READ);
--              chip->read_buf(mtd, p, eccsize);
--              chip->ecc.calculate(mtd, p, &ecc_calc[i]);
--      }
--      chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
-+      int stat;
-       for (i = 0; i < chip->ecc.total; i++)
-               ecc_code[i] = chip->oob_poi[eccpos[i]];
--      eccsteps = chip->ecc.steps;
--      p = buf;
--
--      for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
--              int stat;
-+      for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
-+              chip->ecc.hwctl(mtd, NAND_ECC_READ);
-+              chip->read_buf(mtd, p, eccsize);
-               stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
-               if (stat < 0)
-                       mtd->ecc_stats.failed++;
-               else
-                       mtd->ecc_stats.corrected += stat;
-       }
-+
-       return 0;
- }
-@@ -1178,6 +1171,8 @@ static int nand_do_read_ops(struct mtd_i
-                       bufpoi = aligned ? buf : chip->buffers->databuf;
-                       if (likely(sndcmd)) {
-+                              chip->cmdfunc(mtd, NAND_CMD_READOOB, 0x00, page);
-+                              chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
-                               chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
-                               sndcmd = 0;
-                       }
+