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path: root/drivers/mtd/nand/davinci_nand.c
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Diffstat (limited to 'drivers/mtd/nand/davinci_nand.c')
-rw-r--r--drivers/mtd/nand/davinci_nand.c200
1 files changed, 146 insertions, 54 deletions
diff --git a/drivers/mtd/nand/davinci_nand.c b/drivers/mtd/nand/davinci_nand.c
index 41a9568..d3c6e51 100644
--- a/drivers/mtd/nand/davinci_nand.c
+++ b/drivers/mtd/nand/davinci_nand.c
@@ -59,14 +59,111 @@
static emif_registers *const emif_regs = (void *) DAVINCI_ASYNC_EMIF_CNTRL_BASE;
+/*
+ * Exploit the little endianness of the ARM to do multi-byte transfers
+ * per device read. This can perform over twice as quickly as individual
+ * byte transfers when buffer alignment is conducive.
+ *
+ * NOTE: This only works if the NAND is not connected to the 2 LSBs of
+ * the address bus. On Davinci EVM platforms this has always been true.
+ */
+static void nand_davinci_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+ struct nand_chip *chip = mtd->priv;
+ const u32 *nand = chip->IO_ADDR_R;
+
+ /* Make sure that buf is 32 bit aligned */
+ if (((int)buf & 0x3) != 0) {
+ if (((int)buf & 0x1) != 0) {
+ if (len) {
+ *buf = readb(nand);
+ buf += 1;
+ len--;
+ }
+ }
+
+ if (((int)buf & 0x3) != 0) {
+ if (len >= 2) {
+ *(u16 *)buf = readw(nand);
+ buf += 2;
+ len -= 2;
+ }
+ }
+ }
+
+ /* copy aligned data */
+ while (len >= 4) {
+ *(u32 *)buf = readl(nand);
+ buf += 4;
+ len -= 4;
+ }
+
+ /* mop up any remaining bytes */
+ if (len) {
+ if (len >= 2) {
+ *(u16 *)buf = readw(nand);
+ buf += 2;
+ len -= 2;
+ }
+
+ if (len)
+ *buf = readb(nand);
+ }
+}
+
+static void nand_davinci_write_buf(struct mtd_info *mtd, const uint8_t *buf,
+ int len)
+{
+ struct nand_chip *chip = mtd->priv;
+ const u32 *nand = chip->IO_ADDR_W;
+
+ /* Make sure that buf is 32 bit aligned */
+ if (((int)buf & 0x3) != 0) {
+ if (((int)buf & 0x1) != 0) {
+ if (len) {
+ writeb(*buf, nand);
+ buf += 1;
+ len--;
+ }
+ }
+
+ if (((int)buf & 0x3) != 0) {
+ if (len >= 2) {
+ writew(*(u16 *)buf, nand);
+ buf += 2;
+ len -= 2;
+ }
+ }
+ }
+
+ /* copy aligned data */
+ while (len >= 4) {
+ writel(*(u32 *)buf, nand);
+ buf += 4;
+ len -= 4;
+ }
+
+ /* mop up any remaining bytes */
+ if (len) {
+ if (len >= 2) {
+ writew(*(u16 *)buf, nand);
+ buf += 2;
+ len -= 2;
+ }
+
+ if (len)
+ writeb(*buf, nand);
+ }
+}
+
static void nand_davinci_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
{
struct nand_chip *this = mtd->priv;
u_int32_t IO_ADDR_W = (u_int32_t)this->IO_ADDR_W;
- IO_ADDR_W &= ~(MASK_ALE|MASK_CLE);
-
if (ctrl & NAND_CTRL_CHANGE) {
+ IO_ADDR_W &= ~(MASK_ALE|MASK_CLE);
+
if ( ctrl & NAND_CLE )
IO_ADDR_W |= MASK_CLE;
if ( ctrl & NAND_ALE )
@@ -75,7 +172,7 @@ static void nand_davinci_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int c
}
if (cmd != NAND_CMD_NONE)
- writeb(cmd, this->IO_ADDR_W);
+ writeb(cmd, IO_ADDR_W);
}
#ifdef CONFIG_SYS_NAND_HW_ECC
@@ -248,59 +345,55 @@ static int nand_davinci_4bit_calculate_ecc(struct mtd_info *mtd,
const uint8_t *dat,
uint8_t *ecc_code)
{
- unsigned int hw_4ecc[4] = { 0, 0, 0, 0 };
- unsigned int const1 = 0, const2 = 0;
- unsigned char count1 = 0;
+ unsigned int hw_4ecc[4];
+ unsigned int i;
nand_davinci_4bit_readecc(mtd, hw_4ecc);
/*Convert 10 bit ecc value to 8 bit */
- for (count1 = 0; count1 < 2; count1++) {
- const2 = count1 * 5;
- const1 = count1 * 2;
+ for (i = 0; i < 2; i++) {
+ unsigned int hw_ecc_low = hw_4ecc[i * 2];
+ unsigned int hw_ecc_hi = hw_4ecc[(i * 2) + 1];
/* Take first 8 bits from val1 (count1=0) or val5 (count1=1) */
- ecc_code[const2] = hw_4ecc[const1] & 0xFF;
+ *ecc_code++ = hw_ecc_low & 0xFF;
/*
* Take 2 bits as LSB bits from val1 (count1=0) or val5
* (count1=1) and 6 bits from val2 (count1=0) or
* val5 (count1=1)
*/
- ecc_code[const2 + 1] =
- ((hw_4ecc[const1] >> 8) & 0x3) | ((hw_4ecc[const1] >> 14) &
- 0xFC);
+ *ecc_code++ =
+ ((hw_ecc_low >> 8) & 0x3) | ((hw_ecc_low >> 14) & 0xFC);
/*
* Take 4 bits from val2 (count1=0) or val5 (count1=1) and
* 4 bits from val3 (count1=0) or val6 (count1=1)
*/
- ecc_code[const2 + 2] =
- ((hw_4ecc[const1] >> 22) & 0xF) |
- ((hw_4ecc[const1 + 1] << 4) & 0xF0);
+ *ecc_code++ =
+ ((hw_ecc_low >> 22) & 0xF) | ((hw_ecc_hi << 4) & 0xF0);
/*
* Take 6 bits from val3(count1=0) or val6 (count1=1) and
* 2 bits from val4 (count1=0) or val7 (count1=1)
*/
- ecc_code[const2 + 3] =
- ((hw_4ecc[const1 + 1] >> 4) & 0x3F) |
- ((hw_4ecc[const1 + 1] >> 10) & 0xC0);
+ *ecc_code++ =
+ ((hw_ecc_hi >> 4) & 0x3F) | ((hw_ecc_hi >> 10) & 0xC0);
/* Take 8 bits from val4 (count1=0) or val7 (count1=1) */
- ecc_code[const2 + 4] = (hw_4ecc[const1 + 1] >> 18) & 0xFF;
+ *ecc_code++ = (hw_ecc_hi >> 18) & 0xFF;
}
+
return 0;
}
-
static int nand_davinci_4bit_correct_data(struct mtd_info *mtd, uint8_t *dat,
uint8_t *read_ecc, uint8_t *calc_ecc)
{
- unsigned short ecc_10bit[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
int i;
- unsigned int hw_4ecc[4] = { 0, 0, 0, 0 }, iserror = 0;
- unsigned short *pspare = NULL, *pspare1 = NULL;
+ unsigned int hw_4ecc[4];
+ unsigned int iserror;
+ unsigned short *ecc16;
unsigned int numerrors, erroraddress, errorvalue;
u32 val;
@@ -317,44 +410,41 @@ static int nand_davinci_4bit_correct_data(struct mtd_info *mtd, uint8_t *dat,
return 0;
/* Convert 8 bit in to 10 bit */
- pspare = (unsigned short *)&read_ecc[2];
- pspare1 = (unsigned short *)&read_ecc[0];
+ ecc16 = (unsigned short *)&read_ecc[0];
- /* Take 10 bits from 0th and 1st bytes */
- ecc_10bit[0] = (*pspare1) & 0x3FF;
+ /*
+ * Write the parity values in the NAND Flash 4-bit ECC Load register.
+ * Write each parity value one at a time starting from 4bit_ecc_val8
+ * to 4bit_ecc_val1.
+ */
- /* Take 6 bits from 1st byte and 4 bits from 2nd byte */
- ecc_10bit[1] = (((*pspare1) >> 10) & 0x3F)
- | (((pspare[0]) << 6) & 0x3C0);
+ /*Take 2 bits from 8th byte and 8 bits from 9th byte */
+ writel(((ecc16[4]) >> 6) & 0x3FF, &emif_regs->NAND4BITECCLOAD);
- /* Take 4 bits form 2nd bytes and 6 bits from 3rd bytes */
- ecc_10bit[2] = ((pspare[0]) >> 4) & 0x3FF;
+ /* Take 4 bits from 7th byte and 6 bits from 8th byte */
+ writel((((ecc16[3]) >> 12) & 0xF) | ((((ecc16[4])) << 4) & 0x3F0),
+ &emif_regs->NAND4BITECCLOAD);
- /*Take 2 bits from 3rd byte and 8 bits from 4th byte */
- ecc_10bit[3] = (((pspare[0]) >> 14) & 0x3)
- | ((((pspare[1])) << 2) & 0x3FC);
+ /* Take 6 bits from 6th byte and 4 bits from 7th byte */
+ writel((ecc16[3] >> 2) & 0x3FF, &emif_regs->NAND4BITECCLOAD);
/* Take 8 bits from 5th byte and 2 bits from 6th byte */
- ecc_10bit[4] = ((pspare[1]) >> 8)
- | ((((pspare[2])) << 8) & 0x300);
+ writel(((ecc16[2]) >> 8) | ((((ecc16[3])) << 8) & 0x300),
+ &emif_regs->NAND4BITECCLOAD);
- /* Take 6 bits from 6th byte and 4 bits from 7th byte */
- ecc_10bit[5] = (pspare[2] >> 2) & 0x3FF;
+ /*Take 2 bits from 3rd byte and 8 bits from 4th byte */
+ writel((((ecc16[1]) >> 14) & 0x3) | ((((ecc16[2])) << 2) & 0x3FC),
+ &emif_regs->NAND4BITECCLOAD);
- /* Take 4 bits from 7th byte and 6 bits from 8th byte */
- ecc_10bit[6] = (((pspare[2]) >> 12) & 0xF)
- | ((((pspare[3])) << 4) & 0x3F0);
+ /* Take 4 bits form 2nd bytes and 6 bits from 3rd bytes */
+ writel(((ecc16[1]) >> 4) & 0x3FF, &emif_regs->NAND4BITECCLOAD);
- /*Take 2 bits from 8th byte and 8 bits from 9th byte */
- ecc_10bit[7] = ((pspare[3]) >> 6) & 0x3FF;
+ /* Take 6 bits from 1st byte and 4 bits from 2nd byte */
+ writel((((ecc16[0]) >> 10) & 0x3F) | (((ecc16[1]) << 6) & 0x3C0),
+ &emif_regs->NAND4BITECCLOAD);
- /*
- * Write the parity values in the NAND Flash 4-bit ECC Load register.
- * Write each parity value one at a time starting from 4bit_ecc_val8
- * to 4bit_ecc_val1.
- */
- for (i = 7; i >= 0; i--)
- emif_regs->NAND4BITECCLOAD = ecc_10bit[i];
+ /* Take 10 bits from 0th and 1st bytes */
+ writel((ecc16[0]) & 0x3FF, &emif_regs->NAND4BITECCLOAD);
/*
* Perform a dummy read to the EMIF Revision Code and Status register.
@@ -371,8 +461,7 @@ static int nand_davinci_4bit_correct_data(struct mtd_info *mtd, uint8_t *dat,
*/
nand_davinci_4bit_readecc(mtd, hw_4ecc);
- if (hw_4ecc[0] == ECC_STATE_NO_ERR && hw_4ecc[1] == ECC_STATE_NO_ERR &&
- hw_4ecc[2] == ECC_STATE_NO_ERR && hw_4ecc[3] == ECC_STATE_NO_ERR)
+ if (!(hw_4ecc[0] | hw_4ecc[1] | hw_4ecc[2] | hw_4ecc[3]))
return 0;
/*
@@ -519,6 +608,9 @@ void davinci_nand_init(struct nand_chip *nand)
/* Set address of hardware control function */
nand->cmd_ctrl = nand_davinci_hwcontrol;
+ nand->read_buf = nand_davinci_read_buf;
+ nand->write_buf = nand_davinci_write_buf;
+
nand->dev_ready = nand_davinci_dev_ready;
nand_flash_init();