mtd: bcm47xxnflash: implement reading (3c01d4cb) · Commits · 戴 / test

drivers/mtd/nand/bcm47xxnflash/bcm47xxnflash.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -11,6 +11,7 @@ struct bcm47xxnflash {
		struct mtd_info mtd;

		unsigned curr_command;
		int curr_page_addr;
		int curr_column;

		u8 id_data[8];

drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c

+106 −0

Original line number	Diff line number	Diff line
		@@ -20,6 +20,8 @@
		* shown 164 retries as maxiumum. */
		#define NFLASH_READY_RETRIES 1000

		#define NFLASH_SECTOR_SIZE 512

		/**************************************************
		* Various helpers
		**************************************************/
		@@ -47,6 +49,80 @@ static int bcm47xxnflash_ops_bcm4706_ctl_cmd(struct bcma_drv_cc *cc, u32 code)
		return 0;
		}

		static int bcm47xxnflash_ops_bcm4706_poll(struct bcma_drv_cc *cc)
		{
		int i;

		for (i = 0; i < NFLASH_READY_RETRIES; i++) {
		if (bcma_cc_read32(cc, BCMA_CC_NFLASH_CTL) & 0x04000000) {
		if (bcma_cc_read32(cc, BCMA_CC_NFLASH_CTL) &
		BCMA_CC_NFLASH_CTL_ERR) {
		pr_err("Error on polling\n");
		return -EBUSY;
		} else {
		return 0;
		}
		}
		}

		pr_err("Polling timeout!\n");
		return -EBUSY;
		}

		/**************************************************
		* R/W
		**************************************************/

		static void bcm47xxnflash_ops_bcm4706_read(struct mtd_info mtd, uint8_t buf,
		int len)
		{
		struct nand_chip nand_chip = (struct nand_chip )mtd->priv;
		struct bcm47xxnflash b47n = (struct bcm47xxnflash )nand_chip->priv;

		u32 ctlcode;
		u32 dest = (u32 )buf;
		int i;
		int toread;

		BUG_ON(b47n->curr_page_addr & ~nand_chip->pagemask);
		/* Don't validate column using nand_chip->page_shift, it may be bigger
		* when accessing OOB */

		while (len) {
		/* We can read maximum of 0x200 bytes at once */
		toread = min(len, 0x200);

		/* Set page and column */
		bcma_cc_write32(b47n->cc, BCMA_CC_NFLASH_COL_ADDR,
		b47n->curr_column);
		bcma_cc_write32(b47n->cc, BCMA_CC_NFLASH_ROW_ADDR,
		b47n->curr_page_addr);

		/* Prepare to read */
		ctlcode = 0x40000000 \| 0x00080000 \| 0x00040000 \| 0x00020000 \|
		0x00010000;
		ctlcode \|= NAND_CMD_READSTART << 8;
		if (bcm47xxnflash_ops_bcm4706_ctl_cmd(b47n->cc, ctlcode))
		return;
		if (bcm47xxnflash_ops_bcm4706_poll(b47n->cc))
		return;

		/* Eventually read some data :) */
		for (i = 0; i < toread; i += 4, dest++) {
		ctlcode = 0x40000000 \| 0x30000000 \| 0x00100000;
		if (i == toread - 4) /* Last read goes without that */
		ctlcode &= ~0x40000000;
		if (bcm47xxnflash_ops_bcm4706_ctl_cmd(b47n->cc,
		ctlcode))
		return;
		*dest = bcma_cc_read32(b47n->cc, BCMA_CC_NFLASH_DATA);
		}

		b47n->curr_column += toread;
		len -= toread;
		}
		}

		/**************************************************
		* NAND chip ops
		**************************************************/
		@@ -76,6 +152,8 @@ static void bcm47xxnflash_ops_bcm4706_cmdfunc(struct mtd_info *mtd,

		if (column != -1)
		b47n->curr_column = column;
		if (page_addr != -1)
		b47n->curr_page_addr = page_addr;

		switch (command) {
		case NAND_CMD_RESET:
		@@ -109,6 +187,12 @@ static void bcm47xxnflash_ops_bcm4706_cmdfunc(struct mtd_info *mtd,
		}

		break;
		case NAND_CMD_READ0:
		break;
		case NAND_CMD_READOOB:
		if (page_addr != -1)
		b47n->curr_column += mtd->writesize;
		break;
		default:
		pr_err("Command 0x%X unsupported\n", command);
		break;
		@@ -120,6 +204,7 @@ static u8 bcm47xxnflash_ops_bcm4706_read_byte(struct mtd_info *mtd)
		{
		struct nand_chip nand_chip = (struct nand_chip )mtd->priv;
		struct bcm47xxnflash b47n = (struct bcm47xxnflash )nand_chip->priv;
		u32 tmp = 0;

		switch (b47n->curr_command) {
		case NAND_CMD_READID:
		@@ -129,12 +214,31 @@ static u8 bcm47xxnflash_ops_bcm4706_read_byte(struct mtd_info *mtd)
		return 0;
		}
		return b47n->id_data[b47n->curr_column++];
		case NAND_CMD_READOOB:
		bcm47xxnflash_ops_bcm4706_read(mtd, (u8 *)&tmp, 4);
		return tmp & 0xFF;
		}

		pr_err("Invalid command for byte read: 0x%X\n", b47n->curr_command);
		return 0;
		}

		static void bcm47xxnflash_ops_bcm4706_read_buf(struct mtd_info *mtd,
		uint8_t *buf, int len)
		{
		struct nand_chip nand_chip = (struct nand_chip )mtd->priv;
		struct bcm47xxnflash b47n = (struct bcm47xxnflash )nand_chip->priv;

		switch (b47n->curr_command) {
		case NAND_CMD_READ0:
		case NAND_CMD_READOOB:
		bcm47xxnflash_ops_bcm4706_read(mtd, buf, len);
		return;
		}

		pr_err("Invalid command for buf read: 0x%X\n", b47n->curr_command);
		}

		/**************************************************
		* Init
		**************************************************/
		@@ -153,6 +257,8 @@ int bcm47xxnflash_ops_bcm4706_init(struct bcm47xxnflash *b47n)
		b47n->nand_chip.select_chip = bcm47xxnflash_ops_bcm4706_select_chip;
		b47n->nand_chip.cmdfunc = bcm47xxnflash_ops_bcm4706_cmdfunc;
		b47n->nand_chip.read_byte = bcm47xxnflash_ops_bcm4706_read_byte;
		b47n->nand_chip.read_buf = bcm47xxnflash_ops_bcm4706_read_buf;
		b47n->nand_chip.bbt_options = NAND_BBT_USE_FLASH;
		b47n->nand_chip.ecc.mode = NAND_ECC_NONE; /* TODO: implement ECC */

		/* Enable NAND flash access */

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