[MTD] [NAND] Rename cafe.c to cafe_nand.c and remove the multi-obj magic

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 838 insertions, 0 deletions

diff --git a/drivers/mtd/nand/cafe_nand.c b/drivers/mtd/nand/cafe_nand.c
new file mode 100644
index 00000000000..05f6ec9f5aa
--- /dev/null
+++ b/drivers/mtd/nand/cafe_nand.c
@@ -0,0 +1,838 @@
+/*
+ * Driver for One Laptop Per Child ‘CAFÉ’ controller, aka Marvell 88ALP01
+ *
+ * Copyright © 2006 Red Hat, Inc.
+ * Copyright © 2006 David Woodhouse <dwmw2@infradead.org>
+ */
+
+#define DEBUG
+
+#include <linux/device.h>
+#undef DEBUG
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/rslib.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+#include <asm/io.h>
+
+#define CAFE_NAND_CTRL1		0x00
+#define CAFE_NAND_CTRL2		0x04
+#define CAFE_NAND_CTRL3		0x08
+#define CAFE_NAND_STATUS	0x0c
+#define CAFE_NAND_IRQ		0x10
+#define CAFE_NAND_IRQ_MASK	0x14
+#define CAFE_NAND_DATA_LEN	0x18
+#define CAFE_NAND_ADDR1		0x1c
+#define CAFE_NAND_ADDR2		0x20
+#define CAFE_NAND_TIMING1	0x24
+#define CAFE_NAND_TIMING2	0x28
+#define CAFE_NAND_TIMING3	0x2c
+#define CAFE_NAND_NONMEM	0x30
+#define CAFE_NAND_ECC_RESULT	0x3C
+#define CAFE_NAND_DMA_CTRL	0x40
+#define CAFE_NAND_DMA_ADDR0	0x44
+#define CAFE_NAND_DMA_ADDR1	0x48
+#define CAFE_NAND_ECC_SYN01	0x50
+#define CAFE_NAND_ECC_SYN23	0x54
+#define CAFE_NAND_ECC_SYN45	0x58
+#define CAFE_NAND_ECC_SYN67	0x5c
+#define CAFE_NAND_READ_DATA	0x1000
+#define CAFE_NAND_WRITE_DATA	0x2000
+
+#define CAFE_GLOBAL_CTRL	0x3004
+#define CAFE_GLOBAL_IRQ		0x3008
+#define CAFE_GLOBAL_IRQ_MASK	0x300c
+#define CAFE_NAND_RESET		0x3034
+
+struct cafe_priv {
+	struct nand_chip nand;
+	struct pci_dev *pdev;
+	void __iomem *mmio;
+	struct rs_control *rs;
+	uint32_t ctl1;
+	uint32_t ctl2;
+	int datalen;
+	int nr_data;
+	int data_pos;
+	int page_addr;
+	dma_addr_t dmaaddr;
+	unsigned char *dmabuf;
+};
+
+static int usedma = 1;
+module_param(usedma, int, 0644);
+
+static int skipbbt = 0;
+module_param(skipbbt, int, 0644);
+
+static int debug = 0;
+module_param(debug, int, 0644);
+
+static int regdebug = 0;
+module_param(regdebug, int, 0644);
+
+static int checkecc = 1;
+module_param(checkecc, int, 0644);
+
+static int numtimings;
+static int timing[3];
+module_param_array(timing, int, &numtimings, 0644);
+
+/* Hrm. Why isn't this already conditional on something in the struct device? */
+#define cafe_dev_dbg(dev, args...) do { if (debug) dev_dbg(dev, ##args); } while(0)
+
+/* Make it easier to switch to PIO if we need to */
+#define cafe_readl(cafe, addr)			readl((cafe)->mmio + CAFE_##addr)
+#define cafe_writel(cafe, datum, addr)		writel(datum, (cafe)->mmio + CAFE_##addr)
+
+static int cafe_device_ready(struct mtd_info *mtd)
+{
+	struct cafe_priv *cafe = mtd->priv;
+	int result = !!(cafe_readl(cafe, NAND_STATUS) | 0x40000000);
+	uint32_t irqs = cafe_readl(cafe, NAND_IRQ);
+
+	cafe_writel(cafe, irqs, NAND_IRQ);
+
+	cafe_dev_dbg(&cafe->pdev->dev, "NAND device is%s ready, IRQ %x (%x) (%x,%x)\n",
+		result?"":" not", irqs, cafe_readl(cafe, NAND_IRQ),
+		cafe_readl(cafe, GLOBAL_IRQ), cafe_readl(cafe, GLOBAL_IRQ_MASK));
+
+	return result;
+}
+
+
+static void cafe_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
+{
+	struct cafe_priv *cafe = mtd->priv;
+
+	if (usedma)
+		memcpy(cafe->dmabuf + cafe->datalen, buf, len);
+	else
+		memcpy_toio(cafe->mmio + CAFE_NAND_WRITE_DATA + cafe->datalen, buf, len);
+
+	cafe->datalen += len;
+
+	cafe_dev_dbg(&cafe->pdev->dev, "Copy 0x%x bytes to write buffer. datalen 0x%x\n",
+		len, cafe->datalen);
+}
+
+static void cafe_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+	struct cafe_priv *cafe = mtd->priv;
+
+	if (usedma)
+		memcpy(buf, cafe->dmabuf + cafe->datalen, len);
+	else
+		memcpy_fromio(buf, cafe->mmio + CAFE_NAND_READ_DATA + cafe->datalen, len);
+
+	cafe_dev_dbg(&cafe->pdev->dev, "Copy 0x%x bytes from position 0x%x in read buffer.\n",
+		  len, cafe->datalen);
+	cafe->datalen += len;
+}
+
+static uint8_t cafe_read_byte(struct mtd_info *mtd)
+{
+	struct cafe_priv *cafe = mtd->priv;
+	uint8_t d;
+
+	cafe_read_buf(mtd, &d, 1);
+	cafe_dev_dbg(&cafe->pdev->dev, "Read %02x\n", d);
+
+	return d;
+}
+
+static void cafe_nand_cmdfunc(struct mtd_info *mtd, unsigned command,
+			      int column, int page_addr)
+{
+	struct cafe_priv *cafe = mtd->priv;
+	int adrbytes = 0;
+	uint32_t ctl1;
+	uint32_t doneint = 0x80000000;
+
+	cafe_dev_dbg(&cafe->pdev->dev, "cmdfunc %02x, 0x%x, 0x%x\n",
+		command, column, page_addr);
+
+	if (command == NAND_CMD_ERASE2 || command == NAND_CMD_PAGEPROG) {
+		/* Second half of a command we already calculated */
+		cafe_writel(cafe, cafe->ctl2 | 0x100 | command, NAND_CTRL2);
+		ctl1 = cafe->ctl1;
+		cafe->ctl2 &= ~(1<<30);
+		cafe_dev_dbg(&cafe->pdev->dev, "Continue command, ctl1 %08x, #data %d\n",
+			  cafe->ctl1, cafe->nr_data);
+		goto do_command;
+	}
+	/* Reset ECC engine */
+	cafe_writel(cafe, 0, NAND_CTRL2);
+
+	/* Emulate NAND_CMD_READOOB on large-page chips */
+	if (mtd->writesize > 512 &&
+	    command == NAND_CMD_READOOB) {
+		column += mtd->writesize;
+		command = NAND_CMD_READ0;
+	}
+
+	/* FIXME: Do we need to send read command before sending data
+	   for small-page chips, to position the buffer correctly? */
+
+	if (column != -1) {
+		cafe_writel(cafe, column, NAND_ADDR1);
+		adrbytes = 2;
+		if (page_addr != -1)
+			goto write_adr2;
+	} else if (page_addr != -1) {
+		cafe_writel(cafe, page_addr & 0xffff, NAND_ADDR1);
+		page_addr >>= 16;
+	write_adr2:
+		cafe_writel(cafe, page_addr, NAND_ADDR2);
+		adrbytes += 2;
+		if (mtd->size > mtd->writesize << 16)
+			adrbytes++;
+	}
+
+	cafe->data_pos = cafe->datalen = 0;
+
+	/* Set command valid bit */
+	ctl1 = 0x80000000 | command;
+
+	/* Set RD or WR bits as appropriate */
+	if (command == NAND_CMD_READID || command == NAND_CMD_STATUS) {
+		ctl1 |= (1<<26); /* rd */
+		/* Always 5 bytes, for now */
+		cafe->datalen = 4;
+		/* And one address cycle -- even for STATUS, since the controller doesn't work without */
+		adrbytes = 1;
+	} else if (command == NAND_CMD_READ0 || command == NAND_CMD_READ1 ||
+		   command == NAND_CMD_READOOB || command == NAND_CMD_RNDOUT) {
+		ctl1 |= 1<<26; /* rd */
+		/* For now, assume just read to end of page */
+		cafe->datalen = mtd->writesize + mtd->oobsize - column;
+	} else if (command == NAND_CMD_SEQIN)
+		ctl1 |= 1<<25; /* wr */
+
+	/* Set number of address bytes */
+	if (adrbytes)
+		ctl1 |= ((adrbytes-1)|8) << 27;
+
+	if (command == NAND_CMD_SEQIN || command == NAND_CMD_ERASE1) {
+		/* Ignore the first command of a pair; the hardware
+		   deals with them both at once, later */
+		cafe->ctl1 = ctl1;
+		cafe_dev_dbg(&cafe->pdev->dev, "Setup for delayed command, ctl1 %08x, dlen %x\n",
+			  cafe->ctl1, cafe->datalen);
+		return;
+	}
+	/* RNDOUT and READ0 commands need a following byte */
+	if (command == NAND_CMD_RNDOUT)
+		cafe_writel(cafe, cafe->ctl2 | 0x100 | NAND_CMD_RNDOUTSTART, NAND_CTRL2);
+	else if (command == NAND_CMD_READ0 && mtd->writesize > 512)
+		cafe_writel(cafe, cafe->ctl2 | 0x100 | NAND_CMD_READSTART, NAND_CTRL2);
+
+ do_command:
+	cafe_dev_dbg(&cafe->pdev->dev, "dlen %x, ctl1 %x, ctl2 %x\n",
+		cafe->datalen, ctl1, cafe_readl(cafe, NAND_CTRL2));
+
+	/* NB: The datasheet lies -- we really should be subtracting 1 here */
+	cafe_writel(cafe, cafe->datalen, NAND_DATA_LEN);
+	cafe_writel(cafe, 0x90000000, NAND_IRQ);
+	if (usedma && (ctl1 & (3<<25))) {
+		uint32_t dmactl = 0xc0000000 + cafe->datalen;
+		/* If WR or RD bits set, set up DMA */
+		if (ctl1 & (1<<26)) {
+			/* It's a read */
+			dmactl |= (1<<29);
+			/* ... so it's done when the DMA is done, not just
+			   the command. */
+			doneint = 0x10000000;
+		}
+		cafe_writel(cafe, dmactl, NAND_DMA_CTRL);
+	}
+	cafe->datalen = 0;
+
+	if (unlikely(regdebug)) {
+		int i;
+		printk("About to write command %08x to register 0\n", ctl1);
+		for (i=4; i< 0x5c; i+=4)
+			printk("Register %x: %08x\n", i, readl(cafe->mmio + i));
+	}
+
+	cafe_writel(cafe, ctl1, NAND_CTRL1);
+	/* Apply this short delay always to ensure that we do wait tWB in
+	 * any case on any machine. */
+	ndelay(100);
+
+	if (1) {
+		int c;
+		uint32_t irqs;
+
+		for (c = 500000; c != 0; c--) {
+			irqs = cafe_readl(cafe, NAND_IRQ);
+			if (irqs & doneint)
+				break;
+			udelay(1);
+			if (!(c % 100000))
+				cafe_dev_dbg(&cafe->pdev->dev, "Wait for ready, IRQ %x\n", irqs);
+			cpu_relax();
+		}
+		cafe_writel(cafe, doneint, NAND_IRQ);
+		cafe_dev_dbg(&cafe->pdev->dev, "Command %x completed after %d usec, irqs %x (%x)\n",
+			     command, 500000-c, irqs, cafe_readl(cafe, NAND_IRQ));
+	}
+
+	WARN_ON(cafe->ctl2 & (1<<30));
+
+	switch (command) {
+
+	case NAND_CMD_CACHEDPROG:
+	case NAND_CMD_PAGEPROG:
+	case NAND_CMD_ERASE1:
+	case NAND_CMD_ERASE2:
+	case NAND_CMD_SEQIN:
+	case NAND_CMD_RNDIN:
+	case NAND_CMD_STATUS:
+	case NAND_CMD_DEPLETE1:
+	case NAND_CMD_RNDOUT:
+	case NAND_CMD_STATUS_ERROR:
+	case NAND_CMD_STATUS_ERROR0:
+	case NAND_CMD_STATUS_ERROR1:
+	case NAND_CMD_STATUS_ERROR2:
+	case NAND_CMD_STATUS_ERROR3:
+		cafe_writel(cafe, cafe->ctl2, NAND_CTRL2);
+		return;
+	}
+	nand_wait_ready(mtd);
+	cafe_writel(cafe, cafe->ctl2, NAND_CTRL2);
+}
+
+static void cafe_select_chip(struct mtd_info *mtd, int chipnr)
+{
+	//struct cafe_priv *cafe = mtd->priv;
+	//	cafe_dev_dbg(&cafe->pdev->dev, "select_chip %d\n", chipnr);
+}
+
+static int cafe_nand_interrupt(int irq, void *id)
+{
+	struct mtd_info *mtd = id;
+	struct cafe_priv *cafe = mtd->priv;
+	uint32_t irqs = cafe_readl(cafe, NAND_IRQ);
+	cafe_writel(cafe, irqs & ~0x90000000, NAND_IRQ);
+	if (!irqs)
+		return IRQ_NONE;
+
+	cafe_dev_dbg(&cafe->pdev->dev, "irq, bits %x (%x)\n", irqs, cafe_readl(cafe, NAND_IRQ));
+	return IRQ_HANDLED;
+}
+
+static void cafe_nand_bug(struct mtd_info *mtd)
+{
+	BUG();
+}
+
+static int cafe_nand_write_oob(struct mtd_info *mtd,
+			       struct nand_chip *chip, int page)
+{
+	int status = 0;
+
+	chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page);
+	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
+	chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
+	status = chip->waitfunc(mtd, chip);
+
+	return status & NAND_STATUS_FAIL ? -EIO : 0;
+}
+
+/* Don't use -- use nand_read_oob_std for now */
+static int cafe_nand_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
+			      int page, int sndcmd)
+{
+	chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
+	chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
+	return 1;
+}
+/**
+ * cafe_nand_read_page_syndrome - {REPLACABLE] hardware ecc syndrom based page read
+ * @mtd:	mtd info structure
+ * @chip:	nand chip info structure
+ * @buf:	buffer to store read data
+ *
+ * The hw generator calculates the error syndrome automatically. Therefor
+ * we need a special oob layout and handling.
+ */
+static int cafe_nand_read_page(struct mtd_info *mtd, struct nand_chip *chip,
+			       uint8_t *buf)
+{
+	struct cafe_priv *cafe = mtd->priv;
+
+	cafe_dev_dbg(&cafe->pdev->dev, "ECC result %08x SYN1,2 %08x\n",
+		     cafe_readl(cafe, NAND_ECC_RESULT),
+		     cafe_readl(cafe, NAND_ECC_SYN01));
+
+	chip->read_buf(mtd, buf, mtd->writesize);
+	chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
+
+	if (checkecc && cafe_readl(cafe, NAND_ECC_RESULT) & (1<<18)) {
+		unsigned short syn[8], pat[4];
+		int pos[4];
+		u8 *oob = chip->oob_poi;
+		int i, n;
+
+		for (i=0; i<8; i+=2) {
+			uint32_t tmp = cafe_readl(cafe, NAND_ECC_SYN01 + (i*2));
+			syn[i] = cafe->rs->index_of[tmp & 0xfff];
+			syn[i+1] = cafe->rs->index_of[(tmp >> 16) & 0xfff];
+		}
+
+		n = decode_rs16(cafe->rs, NULL, NULL, 1367, syn, 0, pos, 0,
+		                pat);
+
+		for (i = 0; i < n; i++) {
+			int p = pos[i];
+
+			/* The 12-bit symbols are mapped to bytes here */
+
+			if (p > 1374) {
+				/* out of range */
+				n = -1374;
+			} else if (p == 0) {
+				/* high four bits do not correspond to data */
+				if (pat[i] > 0xff)
+					n = -2048;
+				else
+					buf[0] ^= pat[i];
+			} else if (p == 1365) {
+				buf[2047] ^= pat[i] >> 4;
+				oob[0] ^= pat[i] << 4;
+			} else if (p > 1365) {
+				if ((p & 1) == 1) {
+					oob[3*p/2 - 2048] ^= pat[i] >> 4;
+					oob[3*p/2 - 2047] ^= pat[i] << 4;
+				} else {
+					oob[3*p/2 - 2049] ^= pat[i] >> 8;
+					oob[3*p/2 - 2048] ^= pat[i];
+				}
+			} else if ((p & 1) == 1) {
+				buf[3*p/2] ^= pat[i] >> 4;
+				buf[3*p/2 + 1] ^= pat[i] << 4;
+			} else {
+				buf[3*p/2 - 1] ^= pat[i] >> 8;
+				buf[3*p/2] ^= pat[i];
+			}
+		}
+
+		if (n < 0) {
+			dev_dbg(&cafe->pdev->dev, "Failed to correct ECC at %08x\n",
+				cafe_readl(cafe, NAND_ADDR2) * 2048);
+			for (i = 0; i < 0x5c; i += 4)
+				printk("Register %x: %08x\n", i, readl(cafe->mmio + i));
+			mtd->ecc_stats.failed++;
+		} else {
+			dev_dbg(&cafe->pdev->dev, "Corrected %d symbol errors\n", n);
+			mtd->ecc_stats.corrected += n;
+		}
+	}
+
+	return 0;
+}
+
+static struct nand_ecclayout cafe_oobinfo_2048 = {
+	.eccbytes = 14,
+	.eccpos = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13},
+	.oobfree = {{14, 50}}
+};
+
+/* Ick. The BBT code really ought to be able to work this bit out
+   for itself from the above, at least for the 2KiB case */
+static uint8_t cafe_bbt_pattern_2048[] = { 'B', 'b', 't', '0' };
+static uint8_t cafe_mirror_pattern_2048[] = { '1', 't', 'b', 'B' };
+
+static uint8_t cafe_bbt_pattern_512[] = { 0xBB };
+static uint8_t cafe_mirror_pattern_512[] = { 0xBC };
+
+
+static struct nand_bbt_descr cafe_bbt_main_descr_2048 = {
+	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
+		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
+	.offs =	14,
+	.len = 4,
+	.veroffs = 18,
+	.maxblocks = 4,
+	.pattern = cafe_bbt_pattern_2048
+};
+
+static struct nand_bbt_descr cafe_bbt_mirror_descr_2048 = {
+	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
+		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
+	.offs =	14,
+	.len = 4,
+	.veroffs = 18,
+	.maxblocks = 4,
+	.pattern = cafe_mirror_pattern_2048
+};
+
+static struct nand_ecclayout cafe_oobinfo_512 = {
+	.eccbytes = 14,
+	.eccpos = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13},
+	.oobfree = {{14, 2}}
+};
+
+static struct nand_bbt_descr cafe_bbt_main_descr_512 = {
+	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
+		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
+	.offs =	14,
+	.len = 1,
+	.veroffs = 15,
+	.maxblocks = 4,
+	.pattern = cafe_bbt_pattern_512
+};
+
+static struct nand_bbt_descr cafe_bbt_mirror_descr_512 = {
+	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
+		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
+	.offs =	14,
+	.len = 1,
+	.veroffs = 15,
+	.maxblocks = 4,
+	.pattern = cafe_mirror_pattern_512
+};
+
+
+static void cafe_nand_write_page_lowlevel(struct mtd_info *mtd,
+					  struct nand_chip *chip, const uint8_t *buf)
+{
+	struct cafe_priv *cafe = mtd->priv;
+
+	chip->write_buf(mtd, buf, mtd->writesize);
+	chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
+
+	/* Set up ECC autogeneration */
+	cafe->ctl2 |= (1<<30);
+}
+
+static int cafe_nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
+				const uint8_t *buf, int page, int cached, int raw)
+{
+	int status;
+
+	chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
+
+	if (unlikely(raw))
+		chip->ecc.write_page_raw(mtd, chip, buf);
+	else
+		chip->ecc.write_page(mtd, chip, buf);
+
+	/*
+	 * Cached progamming disabled for now, Not sure if its worth the
+	 * trouble. The speed gain is not very impressive. (2.3->2.6Mib/s)
+	 */
+	cached = 0;
+
+	if (!cached || !(chip->options & NAND_CACHEPRG)) {
+
+		chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
+		status = chip->waitfunc(mtd, chip);
+		/*
+		 * See if operation failed and additional status checks are
+		 * available
+		 */
+		if ((status & NAND_STATUS_FAIL) && (chip->errstat))
+			status = chip->errstat(mtd, chip, FL_WRITING, status,
+					       page);
+
+		if (status & NAND_STATUS_FAIL)
+			return -EIO;
+	} else {
+		chip->cmdfunc(mtd, NAND_CMD_CACHEDPROG, -1, -1);
+		status = chip->waitfunc(mtd, chip);
+	}
+
+#ifdef CONFIG_MTD_NAND_VERIFY_WRITE
+	/* Send command to read back the data */
+	chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
+
+	if (chip->verify_buf(mtd, buf, mtd->writesize))
+		return -EIO;
+#endif
+	return 0;
+}
+
+static int cafe_nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
+{
+	return 0;
+}
+
+/* F_2[X]/(X**6+X+1)  */
+static unsigned short __devinit gf64_mul(u8 a, u8 b)
+{
+	u8 c;
+	unsigned int i;
+
+	c = 0;
+	for (i = 0; i < 6; i++) {
+		if (a & 1)
+			c ^= b;
+		a >>= 1;
+		b <<= 1;
+		if ((b & 0x40) != 0)
+			b ^= 0x43;
+	}
+
+	return c;
+}
+
+/* F_64[X]/(X**2+X+A**-1) with A the generator of F_64[X]  */
+static u16 __devinit gf4096_mul(u16 a, u16 b)
+{
+	u8 ah, al, bh, bl, ch, cl;
+
+	ah = a >> 6;
+	al = a & 0x3f;
+	bh = b >> 6;
+	bl = b & 0x3f;
+
+	ch = gf64_mul(ah ^ al, bh ^ bl) ^ gf64_mul(al, bl);
+	cl = gf64_mul(gf64_mul(ah, bh), 0x21) ^ gf64_mul(al, bl);
+
+	return (ch << 6) ^ cl;
+}
+
+static int __devinit cafe_mul(int x)
+{
+	if (x == 0)
+		return 1;
+	return gf4096_mul(x, 0xe01);
+}
+
+static int __devinit cafe_nand_probe(struct pci_dev *pdev,
+				     const struct pci_device_id *ent)
+{
+	struct mtd_info *mtd;
+	struct cafe_priv *cafe;
+	uint32_t ctrl;
+	int err = 0;
+
+	err = pci_enable_device(pdev);
+	if (err)
+		return err;
+
+	pci_set_master(pdev);
+
+	mtd = kzalloc(sizeof(*mtd) + sizeof(struct cafe_priv), GFP_KERNEL);
+	if (!mtd) {
+		dev_warn(&pdev->dev, "failed to alloc mtd_info\n");
+		return  -ENOMEM;
+	}
+	cafe = (void *)(&mtd[1]);
+
+	mtd->priv = cafe;
+	mtd->owner = THIS_MODULE;
+
+	cafe->pdev = pdev;
+	cafe->mmio = pci_iomap(pdev, 0, 0);
+	if (!cafe->mmio) {
+		dev_warn(&pdev->dev, "failed to iomap\n");
+		err = -ENOMEM;
+		goto out_free_mtd;
+	}
+	cafe->dmabuf = dma_alloc_coherent(&cafe->pdev->dev, 2112 + sizeof(struct nand_buffers),
+					  &cafe->dmaaddr, GFP_KERNEL);
+	if (!cafe->dmabuf) {
+		err = -ENOMEM;
+		goto out_ior;
+	}
+	cafe->nand.buffers = (void *)cafe->dmabuf + 2112;
+
+	cafe->rs = init_rs_non_canonical(12, &cafe_mul, 0, 1, 8);
+	if (!cafe->rs) {
+		err = -ENOMEM;
+		goto out_ior;
+	}
+
+	cafe->nand.cmdfunc = cafe_nand_cmdfunc;
+	cafe->nand.dev_ready = cafe_device_ready;
+	cafe->nand.read_byte = cafe_read_byte;
+	cafe->nand.read_buf = cafe_read_buf;
+	cafe->nand.write_buf = cafe_write_buf;
+	cafe->nand.select_chip = cafe_select_chip;
+
+	cafe->nand.chip_delay = 0;
+
+	/* Enable the following for a flash based bad block table */
+	cafe->nand.options = NAND_USE_FLASH_BBT | NAND_NO_AUTOINCR | NAND_OWN_BUFFERS;
+
+	if (skipbbt) {
+		cafe->nand.options |= NAND_SKIP_BBTSCAN;
+		cafe->nand.block_bad = cafe_nand_block_bad;
+	}
+
+	if (numtimings && numtimings != 3) {
+		dev_warn(&cafe->pdev->dev, "%d timing register values ignored; precisely three are required\n", numtimings);
+	}
+
+	if (numtimings == 3) {
+		cafe_dev_dbg(&cafe->pdev->dev, "Using provided timings (%08x %08x %08x)\n",
+			     timing[0], timing[1], timing[2]);
+	} else {
+		timing[0] = cafe_readl(cafe, NAND_TIMING1);
+		timing[1] = cafe_readl(cafe, NAND_TIMING2);
+		timing[2] = cafe_readl(cafe, NAND_TIMING3);
+
+		if (timing[0] | timing[1] | timing[2]) {
+			cafe_dev_dbg(&cafe->pdev->dev, "Timing registers already set (%08x %08x %08x)\n",
+				     timing[0], timing[1], timing[2]);
+		} else {
+			dev_warn(&cafe->pdev->dev, "Timing registers unset; using most conservative defaults\n");
+			timing[0] = timing[1] = timing[2] = 0xffffffff;
+		}
+	}
+
+	/* Start off by resetting the NAND controller completely */
+	cafe_writel(cafe, 1, NAND_RESET);
+	cafe_writel(cafe, 0, NAND_RESET);
+
+	cafe_writel(cafe, timing[0], NAND_TIMING1);
+	cafe_writel(cafe, timing[1], NAND_TIMING2);
+	cafe_writel(cafe, timing[2], NAND_TIMING3);
+
+	cafe_writel(cafe, 0xffffffff, NAND_IRQ_MASK);
+	err = request_irq(pdev->irq, &cafe_nand_interrupt, IRQF_SHARED,
+			  "CAFE NAND", mtd);
+	if (err) {
+		dev_warn(&pdev->dev, "Could not register IRQ %d\n", pdev->irq);
+		goto out_free_dma;
+	}
+
+	/* Disable master reset, enable NAND clock */
+	ctrl = cafe_readl(cafe, GLOBAL_CTRL);
+	ctrl &= 0xffffeff0;
+	ctrl |= 0x00007000;
+	cafe_writel(cafe, ctrl | 0x05, GLOBAL_CTRL);
+	cafe_writel(cafe, ctrl | 0x0a, GLOBAL_CTRL);
+	cafe_writel(cafe, 0, NAND_DMA_CTRL);
+
+	cafe_writel(cafe, 0x7006, GLOBAL_CTRL);
+	cafe_writel(cafe, 0x700a, GLOBAL_CTRL);
+
+	/* Set up DMA address */
+	cafe_writel(cafe, cafe->dmaaddr & 0xffffffff, NAND_DMA_ADDR0);
+	if (sizeof(cafe->dmaaddr) > 4)
+		/* Shift in two parts to shut the compiler up */
+		cafe_writel(cafe, (cafe->dmaaddr >> 16) >> 16, NAND_DMA_ADDR1);
+	else
+		cafe_writel(cafe, 0, NAND_DMA_ADDR1);
+
+	cafe_dev_dbg(&cafe->pdev->dev, "Set DMA address to %x (virt %p)\n",
+		cafe_readl(cafe, NAND_DMA_ADDR0), cafe->dmabuf);
+
+	/* Enable NAND IRQ in global IRQ mask register */
+	cafe_writel(cafe, 0x80000007, GLOBAL_IRQ_MASK);
+	cafe_dev_dbg(&cafe->pdev->dev, "Control %x, IRQ mask %x\n",
+		cafe_readl(cafe, GLOBAL_CTRL), cafe_readl(cafe, GLOBAL_IRQ_MASK));
+
+	/* Scan to find existence of the device */
+	if (nand_scan_ident(mtd, 1)) {
+		err = -ENXIO;
+		goto out_irq;
+	}
+
+	cafe->ctl2 = 1<<27; /* Reed-Solomon ECC */
+	if (mtd->writesize == 2048)
+		cafe->ctl2 |= 1<<29; /* 2KiB page size */
+
+	/* Set up ECC according to the type of chip we found */
+	if (mtd->writesize == 2048) {
+		cafe->nand.ecc.layout = &cafe_oobinfo_2048;
+		cafe->nand.bbt_td = &cafe_bbt_main_descr_2048;
+		cafe->nand.bbt_md = &cafe_bbt_mirror_descr_2048;
+	} else if (mtd->writesize == 512) {
+		cafe->nand.ecc.layout = &cafe_oobinfo_512;
+		cafe->nand.bbt_td = &cafe_bbt_main_descr_512;
+		cafe->nand.bbt_md = &cafe_bbt_mirror_descr_512;
+	} else {
+		printk(KERN_WARNING "Unexpected NAND flash writesize %d. Aborting\n",
+		       mtd->writesize);
+		goto out_irq;
+	}
+	cafe->nand.ecc.mode = NAND_ECC_HW_SYNDROME;
+	cafe->nand.ecc.size = mtd->writesize;
+	cafe->nand.ecc.bytes = 14;
+	cafe->nand.ecc.hwctl  = (void *)cafe_nand_bug;
+	cafe->nand.ecc.calculate = (void *)cafe_nand_bug;
+	cafe->nand.ecc.correct  = (void *)cafe_nand_bug;
+	cafe->nand.write_page = cafe_nand_write_page;
+	cafe->nand.ecc.write_page = cafe_nand_write_page_lowlevel;
+	cafe->nand.ecc.write_oob = cafe_nand_write_oob;
+	cafe->nand.ecc.read_page = cafe_nand_read_page;
+	cafe->nand.ecc.read_oob = cafe_nand_read_oob;
+
+	err = nand_scan_tail(mtd);
+	if (err)
+		goto out_irq;
+
+	pci_set_drvdata(pdev, mtd);
+	add_mtd_device(mtd);
+	goto out;
+
+ out_irq:
+	/* Disable NAND IRQ in global IRQ mask register */
+	cafe_writel(cafe, ~1 & cafe_readl(cafe, GLOBAL_IRQ_MASK), GLOBAL_IRQ_MASK);
+	free_irq(pdev->irq, mtd);
+ out_free_dma:
+	dma_free_coherent(&cafe->pdev->dev, 2112, cafe->dmabuf, cafe->dmaaddr);
+ out_ior:
+	pci_iounmap(pdev, cafe->mmio);
+ out_free_mtd:
+	kfree(mtd);
+ out:
+	return err;
+}
+
+static void __devexit cafe_nand_remove(struct pci_dev *pdev)
+{
+	struct mtd_info *mtd = pci_get_drvdata(pdev);
+	struct cafe_priv *cafe = mtd->priv;
+
+	del_mtd_device(mtd);
+	/* Disable NAND IRQ in global IRQ mask register */
+	cafe_writel(cafe, ~1 & cafe_readl(cafe, GLOBAL_IRQ_MASK), GLOBAL_IRQ_MASK);
+	free_irq(pdev->irq, mtd);
+	nand_release(mtd);
+	free_rs(cafe->rs);
+	pci_iounmap(pdev, cafe->mmio);
+	dma_free_coherent(&cafe->pdev->dev, 2112, cafe->dmabuf, cafe->dmaaddr);
+	kfree(mtd);
+}
+
+static struct pci_device_id cafe_nand_tbl[] = {
+	{ 0x11ab, 0x4100, PCI_ANY_ID, PCI_ANY_ID, PCI_CLASS_MEMORY_FLASH << 8, 0xFFFF0 }
+};
+
+MODULE_DEVICE_TABLE(pci, cafe_nand_tbl);
+
+static struct pci_driver cafe_nand_pci_driver = {
+	.name = "CAFÉ NAND",
+	.id_table = cafe_nand_tbl,
+	.probe = cafe_nand_probe,
+	.remove = __devexit_p(cafe_nand_remove),
+#ifdef CONFIG_PMx
+	.suspend = cafe_nand_suspend,
+	.resume = cafe_nand_resume,
+#endif
+};
+
+static int cafe_nand_init(void)
+{
+	return pci_register_driver(&cafe_nand_pci_driver);
+}
+
+static void cafe_nand_exit(void)
+{
+	pci_unregister_driver(&cafe_nand_pci_driver);
+}
+module_init(cafe_nand_init);
+module_exit(cafe_nand_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
+MODULE_DESCRIPTION("NAND flash driver for OLPC CAFÉ chip");