[PATCH v3 1/3] mtd: nand: add asm9260 NFC driver

Oleksij Rempel linux at rempel-privat.de
Wed Dec 31 04:58:16 PST 2014


Add driver for Nand Flash Controller used on Alphascales ASM9260 chips.
The IP core of this controller has some similarities with
Evatronix NANDFLASH-CTRL IP (unknown revision), so probably it can be reused
by some other SoCs.

Signed-off-by: Oleksij Rempel <linux at rempel-privat.de>
---
 drivers/mtd/nand/Kconfig        |   7 +
 drivers/mtd/nand/Makefile       |   1 +
 drivers/mtd/nand/asm9260_nand.c | 989 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 997 insertions(+)
 create mode 100644 drivers/mtd/nand/asm9260_nand.c

diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index dd10646..580a608 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -41,6 +41,13 @@ config MTD_SM_COMMON
 	tristate
 	default n
 
+config MTD_NAND_ASM9260
+	tristate "NFC support for ASM9260 SoC"
+	depends on OF
+	default n
+	help
+	  Enable support for the NAND controller found on Alphascale ASM9260 SoC.
+
 config MTD_NAND_DENALI
         tristate "Support Denali NAND controller"
         depends on HAS_DMA
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index 9c847e4..08d660a 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_MTD_NAND_BCH)		+= nand_bch.o
 obj-$(CONFIG_MTD_NAND_IDS)		+= nand_ids.o
 obj-$(CONFIG_MTD_SM_COMMON) 		+= sm_common.o
 
+obj-$(CONFIG_MTD_NAND_ASM9260)		+= asm9260_nand.o
 obj-$(CONFIG_MTD_NAND_CAFE)		+= cafe_nand.o
 obj-$(CONFIG_MTD_NAND_AMS_DELTA)	+= ams-delta.o
 obj-$(CONFIG_MTD_NAND_DENALI)		+= denali.o
diff --git a/drivers/mtd/nand/asm9260_nand.c b/drivers/mtd/nand/asm9260_nand.c
new file mode 100644
index 0000000..23154be
--- /dev/null
+++ b/drivers/mtd/nand/asm9260_nand.c
@@ -0,0 +1,989 @@
+/*
+ * NAND controller driver for Alphascale ASM9260, which is probably
+ * based on Evatronix NANDFLASH-CTRL IP (version unknown)
+ *
+ * Copyright (C), 2014 Oleksij Rempel <linux at rempel-privat.de>
+ *
+ * Inspired by asm9260_nand.c,
+ *	Copyright (C), 2007-2013, Alphascale Tech. Co., Ltd.
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+#include <linux/clk.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/of_mtd.h>
+
+#define ASM9260_ECC_STEP		512
+#define ASM9260_ECC_MAX_BIT		16
+#define ASM9260_MAX_CHIPS		2
+
+#define mtd_to_priv(m)	container_of(m, struct asm9260_nand_priv, mtd)
+
+#define HW_CMD				0x00
+#define BM_CMD_CMD2_S			24
+#define BM_CMD_CMD1_S			16
+#define BM_CMD_CMD0_S			8
+/* 0 - ADDR0, 1 - ADDR1 */
+#define BM_CMD_ADDR1			BIT(7)
+/* 0 - PIO, 1 - DMA */
+#define BM_CMD_DMA			BIT(6)
+#define BM_CMD_CMDSEQ_S			0
+/* single command, wait for RnB */
+#define  SEQ0				0x00
+/* send  cmd, addr, wait tWHR, fetch data */
+#define  SEQ1				0x21
+/* send  cmd, addr, wait RnB, fetch data */
+#define  SEQ2				0x22
+/* send  cmd, addr, wait tADL, send data, wait RnB */
+#define  SEQ3				0x03
+/* send  cmd, wait tWHR, fetch data */
+#define  SEQ4				0x24
+/* send  cmd, 3 x addr, wait tWHR, fetch data */
+#define  SEQ5				0x25
+/* wait tRHW, send  cmd, 2 x addr, cmd, wait tCCS, fetch data */
+#define  SEQ6				0x26
+/* wait tRHW, send  cmd, 35 x addr, cmd, wait tCCS, fetch data */
+#define  SEQ7				0x27
+/* send  cmd, 2 x addr, wait tCCS, fetch data */
+#define  SEQ8				0x08
+/* send  cmd, 5 x addr, wait RnB */
+#define  SEQ9				0x29
+/* send  cmd, 5 x addr, cmd, wait RnB, fetch data  */
+#define  SEQ10				0x2a
+/* send  cmd, wait RnB, fetch data  */
+#define  SEQ11				0x2b
+/* send  cmd, 5 x addr, wait tADL, send data, cmd  */
+#define  SEQ12				0x0c
+/* send  cmd, 5 x addr, wait tADL, send data  */
+#define  SEQ13				0x0d
+/* send  cmd, 3 x addr, cmd, wait RnB */
+#define  SEQ14				0x0e
+/* send  cmd, 5 x addr, cmd, 5 x addr, cmd, wait RnB, fetch data */
+#define  SEQ15				0x2f
+/* send  cmd, 5 x addr, wait RnB, fetch data */
+#define  SEQ17				0x15
+
+#define HW_CTRL				0x04
+#define BM_CTRL_DIS_STATUS		BIT(23)
+#define BM_CTRL_READ_STAT		BIT(22)
+#define BM_CTRL_SMALL_BLOCK_EN		BIT(21)
+#define BM_CTRL_ADDR_CYCLE1_S		18
+#define  ADDR_CYCLE_0			0x0
+#define  ADDR_CYCLE_1			0x1
+#define  ADDR_CYCLE_2			0x2
+#define  ADDR_CYCLE_3			0x3
+#define  ADDR_CYCLE_4			0x4
+#define  ADDR_CYCLE_5			0x5
+#define BM_CTRL_ADDR1_AUTO_INCR		BIT(17)
+#define BM_CTRL_ADDR0_AUTO_INCR		BIT(16)
+#define BM_CTRL_WORK_MODE		BIT(15)
+#define BM_CTRL_PORT_EN			BIT(14)
+#define BM_CTRL_LOOKU_EN		BIT(13)
+#define BM_CTRL_IO_16BIT		BIT(12)
+/* Overwrite BM_CTRL_PAGE_SIZE with HW_DATA_SIZE */
+#define BM_CTRL_CUSTOM_PAGE_SIZE	BIT(11)
+#define BM_CTRL_PAGE_SIZE_S		8
+#define BM_CTRL_PAGE_SIZE(x)		((ffs((x) >> 8) - 1) & 0x7)
+#define  PAGE_SIZE_256B			0x0
+#define  PAGE_SIZE_512B			0x1
+#define  PAGE_SIZE_1024B		0x2
+#define  PAGE_SIZE_2048B		0x3
+#define  PAGE_SIZE_4096B		0x4
+#define  PAGE_SIZE_8192B		0x5
+#define  PAGE_SIZE_16384B		0x6
+#define  PAGE_SIZE_32768B		0x7
+#define BM_CTRL_BLOCK_SIZE_S		6
+#define BM_CTRL_BLOCK_SIZE(x)		((ffs((x) >> 5) - 1) & 0x3)
+#define  BLOCK_SIZE_32P			0x0
+#define  BLOCK_SIZE_64P			0x1
+#define  BLOCK_SIZE_128P		0x2
+#define  BLOCK_SIZE_256P		0x3
+#define BM_CTRL_ECC_EN			BIT(5)
+#define BM_CTRL_INT_EN			BIT(4)
+#define BM_CTRL_SPARE_EN		BIT(3)
+/* same values as BM_CTRL_ADDR_CYCLE1_S */
+#define BM_CTRL_ADDR_CYCLE0_S		0
+
+#define HW_STATUS			0x08
+#define	BM_CTRL_NFC_BUSY		BIT(8)
+/* MEM1_RDY (BIT1) - MEM7_RDY (BIT7) */
+#define	BM_CTRL_MEM0_RDY		BIT(0)
+
+#define HW_INT_MASK			0x0c
+#define HW_INT_STATUS			0x10
+#define BM_INT_FIFO_ERROR		BIT(12)
+#define BM_INT_MEM_RDY_S		4
+/* MEM1_RDY (BIT5) - MEM7_RDY (BIT11) */
+#define BM_INT_MEM0_RDY			BIT(4)
+#define BM_INT_ECC_TRSH_ERR		BIT(3)
+#define BM_INT_ECC_FATAL_ERR		BIT(2)
+#define BM_INT_CMD_END			BIT(1)
+
+#define HW_ECC_CTRL			0x14
+/* bits per 512 bytes */
+#define	BM_ECC_CAP_S			5
+/* support ecc strange 2, 4, 6, 8, 10, 12, 14, 16. */
+#define BM_ECC_CAPn(x)			((((x) >> 1) - 1) & 0x7)
+/* Warn if some bitflip level (threshold) reached. Max 15 bits. */
+#define BM_ECC_ERR_THRESHOLD_S		8
+#define BM_ECC_ERR_THRESHOLD_M		0xf
+#define BM_ECC_ERR_OVER			BIT(2)
+/* Uncorrected error. */
+#define BM_ECC_ERR_UNC			BIT(1)
+/* Corrected error. */
+#define BM_ECC_ERR_CORRECT		BIT(0)
+
+#define HW_ECC_OFFSET			0x18
+#define HW_ADDR0_0			0x1c
+#define HW_ADDR1_0			0x20
+#define HW_ADDR0_1			0x24
+#define HW_ADDR1_1			0x28
+#define HW_SPARE_SIZE			0x30
+#define HW_DMA_ADDR			0x64
+#define HW_DMA_CNT			0x68
+
+#define HW_DMA_CTRL			0x6c
+#define BM_DMA_CTRL_START		BIT(7)
+/* 0 - to device; 1 - from device */
+#define BM_DMA_CTRL_FROM_DEVICE		BIT(6)
+/* 0 - software maneged; 1 - scatter-gather */
+#define BM_DMA_CTRL_SG			BIT(5)
+#define BM_DMA_CTRL_BURST_S		2
+#define  DMA_BURST_INCR4		0x0
+#define  DMA_BURST_STREAM		0x1
+#define  DMA_BURST_SINGLE		0x2
+#define  DMA_BURST_INCR			0x3
+#define  DMA_BURST_INCR8		0x4
+#define  DMA_BURST_INCR16		0x5
+#define BM_DMA_CTRL_ERR			BIT(1)
+#define BM_DMA_CTRL_RDY			BIT(0)
+
+#define HW_MEM_CTRL			0x80
+#define	BM_MEM_CTRL_WP_STATE_MASK	0xff00
+#define	BM_MEM_CTRL_UNWPn(x)		(1 << ((x) + 8))
+#define BM_MEM_CTRL_CEn(x)		(((x) & 7) << 0)
+
+/* BM_CTRL_CUSTOM_PAGE_SIZE should be set */
+#define HW_DATA_SIZE			0x84
+#define HW_READ_STATUS			0x88
+#define HW_TIM_SEQ_0			0x8c
+#define HW_TIMING_ASYN			0x90
+#define HW_TIMING_SYN			0x94
+
+#define HW_FIFO_DATA			0x98
+#define HW_TIME_MODE			0x9c
+#define HW_FIFO_INIT			0xb0
+/*
+ * Counter for ecc related errors.
+ * For each 512 byte block it has 5bit counter.
+ */
+#define HW_ECC_ERR_CNT			0xb8
+
+#define HW_TIM_SEQ_1			0xc8
+
+struct asm9260_nand_priv {
+	struct device		*dev;
+	struct mtd_info		mtd;
+	struct nand_chip	nand;
+	struct nand_ecclayout	ecc_layout;
+
+	struct clk		*clk;
+	struct clk		*clk_ahb;
+
+	void __iomem *base;
+	int irq_done;
+
+	u32 read_cache;
+	int read_cache_cnt;
+	u32 cmd_cache;
+	u32 ctrl_cache;
+	u32 mem_mask;
+	u32 page_cache;
+	unsigned int wait_time;
+
+	unsigned int spare_size;
+};
+
+static void asm9260_reg_rmw(struct asm9260_nand_priv *priv,
+		u32 reg_offset, u32 set, u32 clr)
+{
+	u32 val;
+
+	val = ioread32(priv->base + reg_offset);
+	val &= ~clr;
+	val |= set;
+	iowrite32(val, priv->base + reg_offset);
+}
+
+static void asm9260_select_chip(struct mtd_info *mtd, int chip)
+{
+	struct asm9260_nand_priv *priv = mtd_to_priv(mtd);
+
+	if (chip == -1)
+		iowrite32(BM_MEM_CTRL_WP_STATE_MASK, priv->base + HW_MEM_CTRL);
+	else
+		iowrite32(BM_MEM_CTRL_UNWPn(chip) | BM_MEM_CTRL_CEn(chip),
+			  priv->base + HW_MEM_CTRL);
+}
+
+/* 3 commands are supported by HW. 3-d can be used for TWO PLANE. */
+static void asm9260_nand_cmd_prep(struct asm9260_nand_priv *priv,
+		u8 cmd0, u8 cmd1, u8 cmd2, u8 seq)
+{
+	priv->cmd_cache  = (cmd0 << BM_CMD_CMD0_S) | (cmd1 << BM_CMD_CMD1_S);
+	priv->cmd_cache |= seq << BM_CMD_CMDSEQ_S;
+}
+
+static dma_addr_t asm9260_nand_dma_set(struct mtd_info *mtd, void *buf,
+		enum dma_data_direction dir, size_t size)
+{
+	struct asm9260_nand_priv *priv = mtd_to_priv(mtd);
+	dma_addr_t dma_addr;
+
+	dma_addr = dma_map_single(priv->dev, buf, size, dir);
+	if (dma_mapping_error(priv->dev, dma_addr)) {
+		dev_err(priv->dev, "dma_map_single failed!\n");
+		return dma_addr;
+
+	}
+
+	iowrite32(dma_addr, priv->base + HW_DMA_ADDR);
+	iowrite32(size, priv->base + HW_DMA_CNT);
+	iowrite32(BM_DMA_CTRL_START
+		  | (dir == DMA_FROM_DEVICE ? BM_DMA_CTRL_FROM_DEVICE : 0)
+		  | (DMA_BURST_INCR16 << BM_DMA_CTRL_BURST_S),
+		  priv->base + HW_DMA_CTRL);
+	return dma_addr;
+}
+
+/* complete command request */
+static void asm9260_nand_cmd_comp(struct mtd_info *mtd, int dma)
+{
+	struct asm9260_nand_priv *priv = mtd_to_priv(mtd);
+	int timeout;
+	u32 cmd;
+
+	if (!priv->cmd_cache)
+		return;
+
+	if (dma) {
+		priv->cmd_cache |= BM_CMD_DMA;
+		priv->irq_done = 0;
+		iowrite32(priv->mem_mask << BM_INT_MEM_RDY_S,
+				priv->base + HW_INT_MASK);
+	}
+
+	iowrite32(priv->cmd_cache, priv->base + HW_CMD);
+	cmd = priv->cmd_cache;
+	priv->cmd_cache = 0;
+
+	if (dma) {
+		struct nand_chip *nand = &priv->nand;
+
+		timeout = wait_event_timeout(nand->controller->wq,
+				priv->irq_done,
+				msecs_to_jiffies(priv->wait_time ?
+					priv->wait_time : 20));
+		if (timeout <= 0) {
+			dev_info(priv->dev,
+					"Request 0x%08x timed out\n", cmd);
+			/* TODO: Do something useful here? */
+			/* FIXME: if we have problems on DMA or PIO, we need to
+			 * reset NFC. On asm9260 it is possible only with global
+			 * reset register. How can we use it here? */
+		}
+		priv->wait_time = 0;
+	} else
+		nand_wait_ready(mtd);
+}
+
+static int asm9260_nand_dev_ready(struct mtd_info *mtd)
+{
+	struct asm9260_nand_priv *priv = mtd_to_priv(mtd);
+	u32 tmp;
+
+	tmp = ioread32(priv->base + HW_STATUS);
+
+	return (!(tmp & BM_CTRL_NFC_BUSY) &&
+			(tmp & priv->mem_mask));
+}
+
+static void asm9260_nand_ctrl(struct asm9260_nand_priv *priv, u32 set)
+{
+	iowrite32(priv->ctrl_cache | set, priv->base + HW_CTRL);
+}
+
+static void asm9260_nand_set_addr(struct asm9260_nand_priv *priv,
+		u32 row_addr, u32 column)
+{
+	u32 addr[2];
+
+	addr[0] = (column & 0xffff) | (0xffff0000 & (row_addr << 16));
+	addr[1] = (row_addr >> 16) & 0xff;
+
+	iowrite32(addr[0], priv->base + HW_ADDR0_0);
+	iowrite32(addr[1], priv->base + HW_ADDR0_1);
+}
+
+static void asm9260_nand_command_lp(struct mtd_info *mtd,
+		unsigned int command, int column, int page_addr)
+{
+	struct asm9260_nand_priv *priv = mtd_to_priv(mtd);
+
+	switch (command) {
+	case NAND_CMD_RESET:
+		asm9260_nand_cmd_prep(priv, NAND_CMD_RESET, 0, 0, SEQ0);
+		asm9260_nand_cmd_comp(mtd, 0);
+		break;
+
+	case NAND_CMD_READID:
+		iowrite32(1, priv->base + HW_FIFO_INIT);
+		iowrite32((ADDR_CYCLE_1 << BM_CTRL_ADDR_CYCLE1_S)
+			| BM_CTRL_CUSTOM_PAGE_SIZE
+			| (PAGE_SIZE_4096B << BM_CTRL_PAGE_SIZE_S)
+			| (BLOCK_SIZE_32P << BM_CTRL_BLOCK_SIZE_S)
+			| BM_CTRL_INT_EN
+			| (ADDR_CYCLE_1 << BM_CTRL_ADDR_CYCLE0_S),
+			priv->base + HW_CTRL);
+
+		iowrite32(8, priv->base + HW_DATA_SIZE);
+		iowrite32(column, priv->base + HW_ADDR0_0);
+		asm9260_nand_cmd_prep(priv, NAND_CMD_READID, 0, 0, SEQ1);
+
+		priv->read_cache_cnt = 0;
+		break;
+
+	case NAND_CMD_READOOB:
+		column += mtd->writesize;
+		command = NAND_CMD_READ0;
+	case NAND_CMD_READ0:
+		iowrite32(1, priv->base + HW_FIFO_INIT);
+
+		if (column == 0) {
+			asm9260_nand_ctrl(priv, 0);
+			iowrite32(priv->spare_size, priv->base + HW_SPARE_SIZE);
+		} else if (column == mtd->writesize) {
+			asm9260_nand_ctrl(priv, BM_CTRL_CUSTOM_PAGE_SIZE);
+			iowrite32(mtd->oobsize, priv->base + HW_SPARE_SIZE);
+			iowrite32(mtd->oobsize, priv->base + HW_DATA_SIZE);
+		} else {
+			dev_err(priv->dev, "Couldn't support the column\n");
+			break;
+		}
+
+		asm9260_nand_set_addr(priv, page_addr, column);
+
+		asm9260_nand_cmd_prep(priv, NAND_CMD_READ0,
+				NAND_CMD_READSTART, 0, SEQ10);
+
+		priv->read_cache_cnt = 0;
+		break;
+	case NAND_CMD_SEQIN:
+		iowrite32(1, priv->base + HW_FIFO_INIT);
+
+		if (column == 0) {
+			priv->page_cache = page_addr;
+			asm9260_nand_ctrl(priv, 0);
+			iowrite32(priv->spare_size, priv->base + HW_SPARE_SIZE);
+		} else if (column == mtd->writesize) {
+			asm9260_nand_ctrl(priv, BM_CTRL_CUSTOM_PAGE_SIZE);
+			iowrite32(mtd->oobsize, priv->base + HW_DATA_SIZE);
+		}
+
+		asm9260_nand_set_addr(priv, page_addr, column);
+
+		asm9260_nand_cmd_prep(priv, NAND_CMD_SEQIN, NAND_CMD_PAGEPROG,
+			0, SEQ12);
+
+		break;
+	case NAND_CMD_STATUS:
+		iowrite32(1, priv->base + HW_FIFO_INIT);
+		asm9260_nand_ctrl(priv, BM_CTRL_CUSTOM_PAGE_SIZE);
+
+		/*
+		 * Workaround for status bug.
+		 * Instead of SEQ4 we need to use SEQ1 here, which will
+		 * send cmd with address. For this case we need to make sure
+		 * ADDR == 0.
+		 */
+		asm9260_nand_set_addr(priv, 0, 0);
+		iowrite32(4, priv->base + HW_DATA_SIZE);
+		asm9260_nand_cmd_prep(priv, NAND_CMD_STATUS, 0, 0, SEQ1);
+
+		priv->read_cache_cnt = 0;
+		break;
+
+	case NAND_CMD_ERASE1:
+		priv->wait_time = 400;
+		asm9260_nand_set_addr(priv, page_addr, column);
+
+		asm9260_nand_ctrl(priv, 0);
+
+		/*
+		 * Prepare and send command now. We don't need to split it in
+		 * two stages.
+		 */
+		asm9260_nand_cmd_prep(priv, NAND_CMD_ERASE1, NAND_CMD_ERASE2,
+				0, SEQ14);
+		asm9260_nand_cmd_comp(mtd, 0);
+		break;
+	default:
+		break;
+	}
+}
+
+
+/**
+ * We can't read less then 32 bits on HW_FIFO_DATA. So, to make
+ * read_byte and read_word happy, we use sort of cached 32bit read.
+ * Note: expected values for size should be 1 or 2 bytes.
+ */
+static u32 asm9260_nand_read_cached(struct mtd_info *mtd, int size)
+{
+	struct asm9260_nand_priv *priv = mtd_to_priv(mtd);
+	u8 tmp;
+
+	if ((priv->read_cache_cnt <= 0) || (priv->read_cache_cnt > 4)) {
+		asm9260_nand_cmd_comp(mtd, 0);
+		priv->read_cache = ioread32(priv->base + HW_FIFO_DATA);
+		priv->read_cache_cnt = 4;
+	}
+
+	tmp = priv->read_cache >> (8 * (4 - priv->read_cache_cnt));
+	priv->read_cache_cnt -= size;
+
+	return tmp;
+}
+
+static u8 asm9260_nand_read_byte(struct mtd_info *mtd)
+{
+	return 0xff & asm9260_nand_read_cached(mtd, 1);
+}
+
+static u16 asm9260_nand_read_word(struct mtd_info *mtd)
+{
+	return 0xffff & asm9260_nand_read_cached(mtd, 2);
+}
+
+static void asm9260_nand_read_buf(struct mtd_info *mtd, u8 *buf, int len)
+{
+	struct asm9260_nand_priv *priv = mtd_to_priv(mtd);
+	dma_addr_t dma_addr;
+	int dma_ok = 0;
+
+	if (len & 0x3) {
+		dev_err(priv->dev, "Unsupported length (%x)\n", len);
+		return;
+	}
+
+	/*
+	 * I hate you UBI for your all vmalloc. Be slow as hell with PIO.
+	 * ~ with love from ZeroCopy ~
+	 */
+	if (!is_vmalloc_addr(buf)) {
+		dma_addr = asm9260_nand_dma_set(mtd, buf, DMA_FROM_DEVICE, len);
+		dma_ok = !(dma_mapping_error(priv->dev, dma_addr));
+	}
+	asm9260_nand_cmd_comp(mtd, dma_ok);
+
+	if (dma_ok) {
+		dma_sync_single_for_cpu(priv->dev, dma_addr, len,
+				DMA_FROM_DEVICE);
+		dma_unmap_single(priv->dev, dma_addr, len, DMA_FROM_DEVICE);
+		return;
+	}
+
+	/* fall back to pio mode */
+	len >>= 2;
+	ioread32_rep(priv->base + HW_FIFO_DATA, buf, len);
+}
+
+static void asm9260_nand_write_buf(struct mtd_info *mtd,
+		const u8 *buf, int len)
+{
+	struct asm9260_nand_priv *priv = mtd_to_priv(mtd);
+	dma_addr_t dma_addr;
+	int dma_ok = 0;
+
+	if (len & 0x3) {
+		dev_err(priv->dev, "Unsupported length (%x)\n", len);
+		return;
+	}
+
+	if (!is_vmalloc_addr(buf)) {
+		dma_addr = asm9260_nand_dma_set(mtd,
+				(void *)buf, DMA_TO_DEVICE, len);
+		dma_ok = !(dma_mapping_error(priv->dev, dma_addr));
+	}
+
+	if (dma_ok)
+		dma_sync_single_for_device(priv->dev, dma_addr, len,
+				DMA_TO_DEVICE);
+	asm9260_nand_cmd_comp(mtd, dma_ok);
+
+	if (dma_ok) {
+		dma_unmap_single(priv->dev, dma_addr, len, DMA_TO_DEVICE);
+		return;
+	}
+
+	/* fall back to pio mode */
+	len >>= 2;
+	iowrite32_rep(priv->base + HW_FIFO_DATA, buf, len);
+}
+
+static int asm9260_nand_write_page_raw(struct mtd_info *mtd,
+		struct nand_chip *chip, const u8 *buf,
+		int oob_required)
+{
+	struct asm9260_nand_priv *priv = mtd_to_priv(mtd);
+
+	chip->write_buf(mtd, buf, mtd->writesize);
+	if (oob_required)
+		chip->ecc.write_oob(mtd, chip, priv->page_cache &
+				chip->pagemask);
+	return 0;
+}
+
+static int asm9260_nand_write_page_hwecc(struct mtd_info *mtd,
+		struct nand_chip *chip, const u8 *buf,
+		int oob_required)
+{
+	struct asm9260_nand_priv *priv = mtd_to_priv(mtd);
+
+	asm9260_reg_rmw(priv, HW_CTRL, BM_CTRL_ECC_EN, 0);
+	chip->ecc.write_page_raw(mtd, chip, buf, oob_required);
+
+	return 0;
+}
+
+static unsigned int asm9260_nand_count_ecc(struct asm9260_nand_priv *priv)
+{
+	u32 tmp, i, count, maxcount = 0;
+
+	/* FIXME: this layout was tested only on 2048byte NAND.
+	 * NANDs with bigger page size should use more registers. */
+	tmp = ioread32(priv->base + HW_ECC_ERR_CNT);
+	for (i = 0; i < 4; i++) {
+		count = 0x1f & (tmp >> (5 * i));
+		maxcount = max_t(unsigned int, maxcount, count);
+	}
+
+	return count;
+}
+
+static int asm9260_nand_read_page_hwecc(struct mtd_info *mtd,
+		struct nand_chip *chip, u8 *buf,
+		int oob_required, int page)
+{
+	struct asm9260_nand_priv *priv = mtd_to_priv(mtd);
+	u8 *temp_ptr;
+	u32 status, max_bitflips = 0;
+
+	temp_ptr = buf;
+
+	/* enable ecc */
+	asm9260_reg_rmw(priv, HW_CTRL, BM_CTRL_ECC_EN, 0);
+	chip->read_buf(mtd, temp_ptr, mtd->writesize);
+
+	status = ioread32(priv->base + HW_ECC_CTRL);
+
+	if (status & BM_ECC_ERR_UNC) {
+		u32 ecc_err;
+
+		ecc_err = ioread32(priv->base + HW_ECC_ERR_CNT);
+		/* check if it is erased page (all_DATA_OOB == 0xff) */
+		/* FIXME: should be tested if it is a bullet proof solution.
+		 *  if not, use is_buf_blank. */
+		if (ecc_err != 0x8421)
+			mtd->ecc_stats.failed++;
+
+	} else if (status & BM_ECC_ERR_CORRECT) {
+		max_bitflips = asm9260_nand_count_ecc(priv);
+		mtd->ecc_stats.corrected += max_bitflips;
+	}
+
+	if (oob_required)
+		chip->ecc.read_oob(mtd, chip, page);
+
+	return max_bitflips;
+}
+
+static irqreturn_t asm9260_nand_irq(int irq, void *device_info)
+{
+	struct asm9260_nand_priv *priv = device_info;
+	struct nand_chip *nand = &priv->nand;
+	u32 status;
+
+	status = ioread32(priv->base + HW_INT_STATUS);
+	if (!status)
+		return IRQ_NONE;
+
+	iowrite32(0, priv->base + HW_INT_MASK);
+	iowrite32(0, priv->base + HW_INT_STATUS);
+	priv->irq_done = 1;
+	wake_up(&nand->controller->wq);
+
+	return IRQ_HANDLED;
+}
+
+static void __init asm9260_nand_init_chip(struct nand_chip *nand_chip)
+{
+	nand_chip->select_chip	= asm9260_select_chip;
+	nand_chip->cmdfunc	= asm9260_nand_command_lp;
+	nand_chip->read_byte	= asm9260_nand_read_byte;
+	nand_chip->read_word	= asm9260_nand_read_word;
+	nand_chip->read_buf	= asm9260_nand_read_buf;
+	nand_chip->write_buf	= asm9260_nand_write_buf;
+
+	nand_chip->dev_ready	= asm9260_nand_dev_ready;
+	nand_chip->chip_delay	= 100;
+	nand_chip->options	|= NAND_NO_SUBPAGE_WRITE;
+
+	nand_chip->ecc.write_page	= asm9260_nand_write_page_hwecc;
+	nand_chip->ecc.write_page_raw	= asm9260_nand_write_page_raw;
+	nand_chip->ecc.read_page	= asm9260_nand_read_page_hwecc;
+}
+
+static int __init asm9260_nand_cached_config(struct asm9260_nand_priv *priv)
+{
+	struct nand_chip *nand = &priv->nand;
+	struct mtd_info *mtd = &priv->mtd;
+	u32 addr_cycles, col_cycles, pages_per_block;
+
+	pages_per_block = mtd->erasesize / mtd->writesize;
+	/* max 256P, min 32P */
+	if (pages_per_block & ~(0x000001e0)) {
+		dev_err(priv->dev, "Unsupported erasesize 0x%x\n",
+				mtd->erasesize);
+		return -EINVAL;
+	}
+
+	/* max 32K, min 256. */
+	if (mtd->writesize & ~(0x0000ff00)) {
+		dev_err(priv->dev, "Unsupported writesize 0x%x\n",
+				mtd->erasesize);
+		return -EINVAL;
+	}
+
+	col_cycles  = 2;
+	addr_cycles = col_cycles +
+		(((mtd->size >> mtd->writesize) > 65536) ? 3 : 2);
+
+	priv->ctrl_cache = addr_cycles << BM_CTRL_ADDR_CYCLE1_S
+		| BM_CTRL_PAGE_SIZE(mtd->writesize) << BM_CTRL_PAGE_SIZE_S
+		| BM_CTRL_BLOCK_SIZE(pages_per_block) << BM_CTRL_BLOCK_SIZE_S
+		| BM_CTRL_INT_EN
+		| addr_cycles << BM_CTRL_ADDR_CYCLE0_S;
+
+	iowrite32(BM_ECC_CAPn(nand->ecc.strength) << BM_ECC_CAP_S,
+			priv->base + HW_ECC_CTRL);
+
+	iowrite32(mtd->writesize + priv->spare_size,
+			priv->base + HW_ECC_OFFSET);
+
+	return 0;
+}
+
+static unsigned long __init clk_get_cyc_from_ns(struct clk *clk,
+		unsigned long ns)
+{
+	unsigned int cycle;
+
+	cycle = NSEC_PER_SEC / clk_get_rate(clk);
+	return DIV_ROUND_CLOSEST(ns, cycle);
+}
+
+static void __init asm9260_nand_timing_config(struct asm9260_nand_priv *priv)
+{
+	struct nand_chip *nand = &priv->nand;
+	const struct nand_sdr_timings *time;
+	u32 twhr, trhw, trwh, trwp, tadl, tccs, tsync, trr, twb;
+	int mode;
+
+	mode = nand->onfi_timing_mode_default;
+	dev_info(priv->dev, "ONFI timing mode: %i\n", mode);
+
+	time = onfi_async_timing_mode_to_sdr_timings(mode);
+	if (IS_ERR_OR_NULL(time)) {
+		dev_err(priv->dev, "Can't get onfi_timing_mode: %i\n", mode);
+		return;
+	}
+
+	trwh = clk_get_cyc_from_ns(priv->clk, time->tWH_min / 1000);
+	trwp = clk_get_cyc_from_ns(priv->clk, time->tWP_min / 1000);
+
+	iowrite32((trwh << 4) | (trwp), priv->base + HW_TIMING_ASYN);
+
+	twhr = clk_get_cyc_from_ns(priv->clk, time->tWHR_min / 1000);
+	trhw = clk_get_cyc_from_ns(priv->clk, time->tRHW_min / 1000);
+	tadl = clk_get_cyc_from_ns(priv->clk, time->tADL_min / 1000);
+	/* tCCS - change read/write collumn. Time between last cmd and data. */
+	tccs = clk_get_cyc_from_ns(priv->clk,
+			(time->tCLR_min + time->tCLH_min + time->tRC_min)
+			/ 1000);
+
+	iowrite32((twhr << 24) | (trhw << 16)
+		| (tadl << 8) | (tccs), priv->base + HW_TIM_SEQ_0);
+
+	trr = clk_get_cyc_from_ns(priv->clk, time->tRR_min / 1000);
+	tsync = 0; /* ??? */
+	twb = clk_get_cyc_from_ns(priv->clk, time->tWB_max / 1000);
+	iowrite32((tsync << 16) | (trr << 9) | (twb),
+			priv->base + HW_TIM_SEQ_1);
+}
+
+static int __init asm9260_nand_ecc_conf(struct asm9260_nand_priv *priv)
+{
+	struct device_node *np = priv->dev->of_node;
+	struct nand_chip *nand = &priv->nand;
+	struct mtd_info *mtd = &priv->mtd;
+	struct nand_ecclayout *ecc_layout = &priv->ecc_layout;
+	int i, ecc_strength;
+
+	nand->ecc.mode = of_get_nand_ecc_mode(np);
+	switch (nand->ecc.mode) {
+	case NAND_ECC_SOFT:
+	case NAND_ECC_SOFT_BCH:
+		dev_info(priv->dev, "Using soft ECC %i\n", nand->ecc.mode);
+		/* nand_base will find needed settings */
+		return 0;
+	case NAND_ECC_HW:
+	default:
+		dev_info(priv->dev, "Using default NAND_ECC_HW\n");
+		nand->ecc.mode = NAND_ECC_HW;
+		break;
+	}
+
+	ecc_strength = of_get_nand_ecc_strength(np);
+	nand->ecc.size = ASM9260_ECC_STEP;
+	nand->ecc.steps = mtd->writesize / nand->ecc.size;
+
+	if (ecc_strength < nand->ecc_strength_ds) {
+		int ds_corr;
+
+		/* Let's check if ONFI can help us. */
+		if (nand->ecc_strength_ds <= 0) {
+			/* No ONFI and no DT - it is bad. */
+			dev_err(priv->dev,
+					"nand-ecc-strength is not set by DT or ONFI. Please set nand-ecc-strength in DT or add chip quirk in nand_ids.c.\n");
+			return -EINVAL;
+		}
+
+		ds_corr = (mtd->writesize * nand->ecc_strength_ds) /
+			nand->ecc_step_ds;
+		ecc_strength = ds_corr / nand->ecc.steps;
+		dev_info(priv->dev, "ONFI:nand-ecc-strength = %i\n",
+				ecc_strength);
+	} else
+		dev_info(priv->dev, "DT:nand-ecc-strength = %i\n",
+				ecc_strength);
+
+	if (ecc_strength == 0 || ecc_strength > ASM9260_ECC_MAX_BIT) {
+		dev_err(priv->dev,
+				"Not supported ecc_strength value: %i\n",
+				ecc_strength);
+		return -EINVAL;
+	}
+
+	if (ecc_strength & 0x1) {
+		ecc_strength++;
+		dev_info(priv->dev,
+				"Only even ecc_strength value is supported. Recalculating: %i\n",
+		       ecc_strength);
+	}
+
+	/* FIXME: do we have max or min page size? */
+
+	/* 13 - the smallest integer for 512 (ASM9260_ECC_STEP). Div to 8bit. */
+	nand->ecc.bytes = DIV_ROUND_CLOSEST(ecc_strength * 13, 8);
+
+	ecc_layout->eccbytes = nand->ecc.bytes * nand->ecc.steps;
+	nand->ecc.layout = ecc_layout;
+	nand->ecc.strength = ecc_strength;
+
+	priv->spare_size = mtd->oobsize - ecc_layout->eccbytes;
+
+	ecc_layout->oobfree[0].offset = 2;
+	ecc_layout->oobfree[0].length = priv->spare_size - 2;
+
+	/* FIXME: can we use same layout as SW_ECC? */
+	for (i = 0; i < ecc_layout->eccbytes; i++)
+		ecc_layout->eccpos[i] = priv->spare_size + i;
+
+	return 0;
+}
+
+static int __init asm9260_nand_get_dt_clks(struct asm9260_nand_priv *priv)
+{
+	int clk_idx = 0, err;
+
+	priv->clk = devm_clk_get(priv->dev, "sys");
+	if (IS_ERR(priv->clk))
+		goto out_err;
+
+	/* configure AHB clock */
+	clk_idx = 1;
+	priv->clk_ahb = devm_clk_get(priv->dev, "ahb");
+	if (IS_ERR(priv->clk_ahb))
+		goto out_err;
+
+	err = clk_prepare_enable(priv->clk_ahb);
+	if (err)
+		dev_err(priv->dev, "Failed to enable ahb_clk!\n");
+
+	err = clk_set_rate(priv->clk, clk_get_rate(priv->clk_ahb));
+	if (err) {
+		clk_disable_unprepare(priv->clk_ahb);
+		dev_err(priv->dev, "Failed to set rate!\n");
+	}
+
+	err = clk_prepare_enable(priv->clk);
+	if (err) {
+		clk_disable_unprepare(priv->clk_ahb);
+		dev_err(priv->dev, "Failed to enable clk!\n");
+	}
+
+	return 0;
+out_err:
+	dev_err(priv->dev, "%s: Failed to get clk (%i)\n", __func__, clk_idx);
+	return 1;
+}
+
+static int __init asm9260_nand_probe(struct platform_device *pdev)
+{
+	struct asm9260_nand_priv *priv;
+	struct nand_chip *nand;
+	struct mtd_info *mtd;
+	struct device_node *np = pdev->dev.of_node;
+	struct resource *r;
+	int ret, i;
+	unsigned int irq;
+	u32 val;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(struct asm9260_nand_priv),
+			GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(&pdev->dev, r);
+	if (!priv->base) {
+		dev_err(&pdev->dev, "Unable to map resource!\n");
+		return -EINVAL;
+	}
+
+	priv->dev = &pdev->dev;
+	nand = &priv->nand;
+	nand->priv = priv;
+
+	platform_set_drvdata(pdev, priv);
+	mtd = &priv->mtd;
+	mtd->priv = nand;
+	mtd->owner = THIS_MODULE;
+	mtd->name = dev_name(&pdev->dev);
+
+	if (asm9260_nand_get_dt_clks(priv))
+		return -ENODEV;
+
+	irq = platform_get_irq(pdev, 0);
+	if (!irq)
+		return -ENODEV;
+
+	iowrite32(0, priv->base + HW_INT_MASK);
+	ret = devm_request_irq(priv->dev, irq, asm9260_nand_irq,
+				IRQF_ONESHOT | IRQF_SHARED,
+				dev_name(&pdev->dev), priv);
+
+	asm9260_nand_init_chip(nand);
+
+	ret = of_property_read_u32(np, "nand-max-chips", &val);
+	if (ret)
+		val = 1;
+
+	if (val > ASM9260_MAX_CHIPS) {
+		dev_err(&pdev->dev, "Unsupported nand-max-chips value: %i\n",
+				val);
+		return -ENODEV;
+	}
+
+	for (i = 0; i < val; i++)
+		priv->mem_mask |= BM_CTRL_MEM0_RDY << i;
+
+	ret = nand_scan_ident(mtd, val, NULL);
+	if (ret) {
+		dev_err(&pdev->dev, "scan_ident filed!\n");
+		return ret;
+	}
+
+	if (of_get_nand_on_flash_bbt(np)) {
+		dev_info(&pdev->dev, "Use On Flash BBT\n");
+		nand->bbt_options = NAND_BBT_USE_FLASH | NAND_BBT_NO_OOB_BBM
+			| NAND_BBT_LASTBLOCK;
+	}
+
+	asm9260_nand_timing_config(priv);
+	asm9260_nand_ecc_conf(priv);
+	ret = asm9260_nand_cached_config(priv);
+	if (ret)
+		return ret;
+
+	/* second phase scan */
+	if (nand_scan_tail(mtd)) {
+		dev_err(&pdev->dev, "scan_tail filed!\n");
+		return -ENXIO;
+	}
+
+
+	ret = mtd_device_parse_register(mtd, NULL,
+			&(struct mtd_part_parser_data) {
+				.of_node = pdev->dev.of_node,
+			},
+			NULL, 0);
+
+	return ret;
+}
+
+
+static int asm9260_nand_remove(struct platform_device *pdev)
+{
+	struct asm9260_nand_priv *priv = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(priv->clk);
+	clk_disable_unprepare(priv->clk_ahb);
+	nand_release(&priv->mtd);
+
+	return 0;
+}
+
+static const struct of_device_id asm9260_nand_match[] = {
+	{
+		.compatible   = "alphascale,asm9260-nand",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, asm9260_nand_match);
+
+static struct platform_driver asm9260_nand_driver = {
+	.probe		= asm9260_nand_probe,
+	.remove		= asm9260_nand_remove,
+	.driver		= {
+		.name	= "asm9260_nand",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(asm9260_nand_match),
+	},
+};
+
+module_platform_driver(asm9260_nand_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("ASM9260 NAND driver");
-- 
1.9.1




More information about the linux-mtd mailing list