mtd: nand: new base driver for memory mapped nand devices

The BF537-STAMP Blackfin board had a driver for working with NAND devices
that are simply memory mapped.  Since there is nothing Blackfin specific
about this, generalize the driver a bit so that everyone can leverage it.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Scott Wood <scottwood@freescale.com>

board/bf537-stamp/Makefile

@@ -32,7 +32,6 @@ LIB	= $(obj)lib$(BOARD).a
 COBJS-y	:= $(BOARD).o cmd_bf537led.o
 COBJS-$(CONFIG_BFIN_IDE)   += ide-cf.o
 COBJS-$(CONFIG_CMD_EEPROM) += spi_flash.o
-COBJS-$(CONFIG_CMD_NAND)   += nand.o
 COBJS-$(CONFIG_POST)       += post.o post-memory.o
 
 SRCS	:= $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c)

board/bf537-stamp/nand.c

@@ -1,100 +0,0 @@
-/*
- * Copyright (c) 2006-2007 Analog Devices Inc.
- *
- * See file CREDITS for list of people who contributed to this
- * project.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
- */
-
-#include <common.h>
-#include <asm/io.h>
-
-#include <nand.h>
-
-#define CONCAT(a,b,c,d) a ## b ## c ## d
-#define PORT(a,b)  CONCAT(pPORT,a,b,)
-
-#ifndef CONFIG_NAND_GPIO_PORT
-#define CONFIG_NAND_GPIO_PORT F
-#endif
-
-/*
- * hardware specific access to control-lines
- */
-static void bfin_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
-{
-	register struct nand_chip *this = mtd->priv;
-	u32 IO_ADDR_W = (u32) this->IO_ADDR_W;
-
-	if (ctrl & NAND_CTRL_CHANGE) {
-		if (ctrl & NAND_CLE)
-			IO_ADDR_W = CONFIG_SYS_NAND_BASE + BFIN_NAND_CLE;
-		else
-			IO_ADDR_W = CONFIG_SYS_NAND_BASE;
-		if (ctrl & NAND_ALE)
-			IO_ADDR_W = CONFIG_SYS_NAND_BASE + BFIN_NAND_ALE;
-		else
-			IO_ADDR_W = CONFIG_SYS_NAND_BASE;
-		this->IO_ADDR_W = (void __iomem *) IO_ADDR_W;
-	}
-	this->IO_ADDR_R = this->IO_ADDR_W;
-
-	/* Drain the writebuffer */
-	SSYNC();
-
-	if (cmd != NAND_CMD_NONE)
-		writeb(cmd, this->IO_ADDR_W);
-}
-
-int bfin_device_ready(struct mtd_info *mtd)
-{
-	int ret = (*PORT(CONFIG_NAND_GPIO_PORT, IO) & BFIN_NAND_READY) ? 1 : 0;
-	SSYNC();
-	return ret;
-}
-
-/*
- * Board-specific NAND initialization. The following members of the
- * argument are board-specific (per include/linux/mtd/nand.h):
- * - IO_ADDR_R?: address to read the 8 I/O lines of the flash device
- * - IO_ADDR_W?: address to write the 8 I/O lines of the flash device
- * - cmd_ctrl: hardwarespecific function for accesing control-lines
- * - dev_ready: hardwarespecific function for  accesing device ready/busy line
- * - enable_hwecc?: function to enable (reset)  hardware ecc generator. Must
- *   only be provided if a hardware ECC is available
- * - ecc.mode: mode of ecc, see defines
- * - chip_delay: chip dependent delay for transfering data from array to
- *   read regs (tR)
- * - options: various chip options. They can partly be set to inform
- *   nand_scan about special functionality. See the defines for further
- *   explanation
- * Members with a "?" were not set in the merged testing-NAND branch,
- * so they are not set here either.
- */
-int board_nand_init(struct nand_chip *nand)
-{
-	*PORT(CONFIG_NAND_GPIO_PORT, _FER) &= ~BFIN_NAND_READY;
-	*PORT(CONFIG_NAND_GPIO_PORT, IO_DIR) &= ~BFIN_NAND_READY;
-	*PORT(CONFIG_NAND_GPIO_PORT, IO_INEN) |= BFIN_NAND_READY;
-
-	nand->cmd_ctrl = bfin_hwcontrol;
-	nand->ecc.mode = NAND_ECC_SOFT;
-	nand->dev_ready = bfin_device_ready;
-	nand->chip_delay = 30;
-
-	return 0;
-}

drivers/mtd/nand/Makefile

@@ -45,6 +45,7 @@ COBJS-$(CONFIG_NAND_NOMADIK) += nomadik.o
 COBJS-$(CONFIG_NAND_S3C2410) += s3c2410_nand.c
 COBJS-$(CONFIG_NAND_S3C64XX) += s3c64xx.o
 COBJS-$(CONFIG_NAND_OMAP_GPMC) += omap_gpmc.o
+COBJS-$(CONFIG_NAND_PLAT) += nand_plat.o
 endif
 
 COBJS	:= $(COBJS-y)

drivers/mtd/nand/nand_plat.c

@@ -0,0 +1,53 @@
+/*
+ * Genericish driver for memory mapped NAND devices
+ *
+ * Copyright (c) 2006-2009 Analog Devices Inc.
+ * Licensed under the GPL-2 or later.
+ */
+
+/* Your board must implement the following macros:
+ *  NAND_PLAT_WRITE_CMD(chip, cmd)
+ *  NAND_PLAT_WRITE_ADR(chip, cmd)
+ *  NAND_PLAT_INIT()
+ *
+ * It may also implement the following:
+ *  NAND_PLAT_DEV_READY(chip)
+ */
+
+#include <common.h>
+#include <asm/io.h>
+
+#include <nand.h>
+
+static void plat_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
+{
+	struct nand_chip *this = mtd->priv;
+
+	if (cmd == NAND_CMD_NONE)
+		return;
+
+	if (ctrl & NAND_CLE)
+		NAND_PLAT_WRITE_CMD(this, cmd);
+	else
+		NAND_PLAT_WRITE_ADR(this, cmd);
+}
+
+#ifdef NAND_PLAT_DEV_READY
+static int plat_dev_ready(struct mtd_info *mtd)
+{
+	return NAND_PLAT_DEV_READY((struct nand_chip *)mtd->priv);
+}
+#else
+# define plat_dev_ready NULL
+#endif
+
+int board_nand_init(struct nand_chip *nand)
+{
+	NAND_PLAT_INIT();
+
+	nand->cmd_ctrl = plat_cmd_ctrl;
+	nand->dev_ready = plat_dev_ready;
+	nand->ecc.mode = NAND_ECC_SOFT;
+
+	return 0;
+}

include/configs/bf537-stamp.h

@@ -151,36 +151,28 @@
 /*
  * NAND Settings
  */
-/* #define CONFIG_BF537_NAND */
+/* #define CONFIG_NAND_PLAT */
-#ifdef CONFIG_BF537_NAND
+#define CONFIG_SYS_NAND_BASE		0x20212000
-# define CONFIG_CMD_NAND
-#endif
-
-#define CONFIG_SYS_NAND_ADDR		0x20212000
-#define CONFIG_SYS_NAND_BASE		CONFIG_SYS_NAND_ADDR
 #define CONFIG_SYS_MAX_NAND_DEVICE	1
-#define SECTORSIZE		512
-#define ADDR_COLUMN		1
-#define ADDR_PAGE		2
-#define ADDR_COLUMN_PAGE	3
-#define NAND_ChipID_UNKNOWN	0x00
-#define NAND_MAX_FLOORS		1
-#define BFIN_NAND_READY		PF3
 
-#define NAND_WAIT_READY(nand) \
+#define BFIN_NAND_CLE(chip) ((unsigned long)(chip)->IO_ADDR_W | (1 << 2))
+#define BFIN_NAND_ALE(chip) ((unsigned long)(chip)->IO_ADDR_W | (1 << 1))
+#define BFIN_NAND_READY     PF3
+#define BFIN_NAND_WRITE(addr, cmd) \
 	do { \
-		int timeout = 0; \
+		bfin_write8(addr, cmd); \
-		while (!(*pPORTFIO & PF3)) \
+		SSYNC(); \
-			if (timeout++ > 100000) \
-				break; \
 	} while (0)
 
-#define BFIN_NAND_CLE		(1 << 2)	/* A2 -> Command Enable */
+#define NAND_PLAT_WRITE_CMD(chip, cmd) BFIN_NAND_WRITE(BFIN_NAND_CLE(chip), cmd)
-#define BFIN_NAND_ALE		(1 << 1)	/* A1 -> Address Enable */
+#define NAND_PLAT_WRITE_ADR(chip, cmd) BFIN_NAND_WRITE(BFIN_NAND_ALE(chip), cmd)
-#define WRITE_NAND_COMMAND(d, adr) bfin_write8(adr | BFIN_NAND_CLE, d)
+#define NAND_PLAT_DEV_READY(chip)      (bfin_read_PORTFIO() & BFIN_NAND_READY)
-#define WRITE_NAND_ADDRESS(d, adr) bfin_write8(adr | BFIN_NAND_ALE, d)
+#define NAND_PLAT_INIT() \
-#define WRITE_NAND(d, adr)         bfin_write8(adr, d)
+	do { \
-#define READ_NAND(adr)             bfin_read8(adr)
+		bfin_write_PORTF_FER(bfin_read_PORTF_FER() & ~BFIN_NAND_READY); \
+		bfin_write_PORTFIO_DIR(bfin_read_PORTFIO_DIR() & ~BFIN_NAND_READY); \
+		bfin_write_PORTFIO_INEN(bfin_read_PORTFIO_INEN() | BFIN_NAND_READY); \
+	} while (0)
 
 
 /*

include/configs/bfin_adi_common.h

@@ -38,6 +38,9 @@
 #  define CONFIG_CMD_USB_STORAGE
 #  define CONFIG_DOS_PARTITION
 # endif
+# ifdef CONFIG_NAND_PLAT
+#  define CONFIG_CMD_NAND
+# endif
 # ifdef CONFIG_POST
 #  define CONFIG_CMD_DIAG
 # endif