mtd: Add DiskOnChip G3 support

Add support for DiskOnChip G3 chips. The support is quite
limited yet :
 - no flash writes/erases are implemented
 - ECC fixes are not implemented
 - powerdown is not implemented
 - IPL handling is not yet done

On the brighter side, the chip reading does work.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
diff --git a/drivers/mtd/devices/docg3.h b/drivers/mtd/devices/docg3.h
new file mode 100644
index 0000000..0d407be
--- /dev/null
+++ b/drivers/mtd/devices/docg3.h
@@ -0,0 +1,297 @@
+/*
+ * Handles the M-Systems DiskOnChip G3 chip
+ *
+ * Copyright (C) 2011 Robert Jarzmik
+ *
+ * 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
+ *
+ */
+
+#ifndef _MTD_DOCG3_H
+#define _MTD_DOCG3_H
+
+/*
+ * Flash memory areas :
+ *   - 0x0000 .. 0x07ff : IPL
+ *   - 0x0800 .. 0x0fff : Data area
+ *   - 0x1000 .. 0x17ff : Registers
+ *   - 0x1800 .. 0x1fff : Unknown
+ */
+#define DOC_IOSPACE_IPL			0x0000
+#define DOC_IOSPACE_DATA		0x0800
+#define DOC_IOSPACE_SIZE		0x2000
+
+/*
+ * DOC G3 layout and adressing scheme
+ *   A page address for the block "b", plane "P" and page "p":
+ *   address = [bbbb bPpp pppp]
+ */
+
+#define DOC_ADDR_PAGE_MASK		0x3f
+#define DOC_ADDR_BLOCK_SHIFT		6
+#define DOC_LAYOUT_NBPLANES		2
+#define DOC_LAYOUT_PAGES_PER_BLOCK	64
+#define DOC_LAYOUT_PAGE_SIZE		512
+#define DOC_LAYOUT_OOB_SIZE		16
+#define DOC_LAYOUT_WEAR_SIZE		8
+#define DOC_LAYOUT_PAGE_OOB_SIZE				\
+	(DOC_LAYOUT_PAGE_SIZE + DOC_LAYOUT_OOB_SIZE)
+#define DOC_LAYOUT_WEAR_OFFSET		(DOC_LAYOUT_PAGE_OOB_SIZE * 2)
+#define DOC_LAYOUT_BLOCK_SIZE					\
+	(DOC_LAYOUT_PAGES_PER_BLOCK * DOC_LAYOUT_PAGE_SIZE)
+#define DOC_ECC_BCH_SIZE		7
+#define DOC_ECC_BCH_COVERED_BYTES				\
+	(DOC_LAYOUT_PAGE_SIZE + DOC_LAYOUT_OOB_PAGEINFO_SZ +	\
+	 DOC_LAYOUT_OOB_HAMMING_SZ + DOC_LAYOUT_OOB_BCH_SZ)
+
+/*
+ * Blocks distribution
+ */
+#define DOC_LAYOUT_BLOCK_BBT		0
+#define DOC_LAYOUT_BLOCK_OTP		0
+#define DOC_LAYOUT_BLOCK_FIRST_DATA	6
+
+#define DOC_LAYOUT_PAGE_BBT		4
+
+/*
+ * Extra page OOB (16 bytes wide) layout
+ */
+#define DOC_LAYOUT_OOB_PAGEINFO_OFS	0
+#define DOC_LAYOUT_OOB_HAMMING_OFS	7
+#define DOC_LAYOUT_OOB_BCH_OFS		8
+#define DOC_LAYOUT_OOB_UNUSED_OFS	15
+#define DOC_LAYOUT_OOB_PAGEINFO_SZ	7
+#define DOC_LAYOUT_OOB_HAMMING_SZ	1
+#define DOC_LAYOUT_OOB_BCH_SZ		7
+#define DOC_LAYOUT_OOB_UNUSED_SZ	1
+
+
+#define DOC_CHIPID_G3			0x200
+#define DOC_ERASE_MARK			0xaa
+/*
+ * Flash registers
+ */
+#define DOC_CHIPID			0x1000
+#define DOC_TEST			0x1004
+#define DOC_BUSLOCK			0x1006
+#define DOC_ENDIANCONTROL		0x1008
+#define DOC_DEVICESELECT		0x100a
+#define DOC_ASICMODE			0x100c
+#define DOC_CONFIGURATION		0x100e
+#define DOC_INTERRUPTCONTROL		0x1010
+#define DOC_READADDRESS			0x101a
+#define DOC_DATAEND			0x101e
+#define DOC_INTERRUPTSTATUS		0x1020
+
+#define DOC_FLASHSEQUENCE		0x1032
+#define DOC_FLASHCOMMAND		0x1034
+#define DOC_FLASHADDRESS		0x1036
+#define DOC_FLASHCONTROL		0x1038
+#define DOC_NOP				0x103e
+
+#define DOC_ECCCONF0			0x1040
+#define DOC_ECCCONF1			0x1042
+#define DOC_ECCPRESET			0x1044
+#define DOC_HAMMINGPARITY		0x1046
+#define DOC_BCH_SYNDROM(idx)		(0x1048 + (idx << 1))
+
+#define DOC_PROTECTION			0x1056
+#define DOC_DPS0_ADDRLOW		0x1060
+#define DOC_DPS0_ADDRHIGH		0x1062
+#define DOC_DPS1_ADDRLOW		0x1064
+#define DOC_DPS1_ADDRHIGH		0x1066
+#define DOC_DPS0_STATUS			0x106c
+#define DOC_DPS1_STATUS			0x106e
+
+#define DOC_ASICMODECONFIRM		0x1072
+#define DOC_CHIPID_INV			0x1074
+
+/*
+ * Flash sequences
+ * A sequence is preset before one or more commands are input to the chip.
+ */
+#define DOC_SEQ_RESET			0x00
+#define DOC_SEQ_PAGE_SIZE_532		0x03
+#define DOC_SEQ_SET_MODE		0x09
+#define DOC_SEQ_READ			0x12
+#define DOC_SEQ_SET_PLANE1		0x0e
+#define DOC_SEQ_SET_PLANE2		0x10
+#define DOC_SEQ_PAGE_SETUP		0x1d
+
+/*
+ * Flash commands
+ */
+#define DOC_CMD_READ_PLANE1		0x00
+#define DOC_CMD_SET_ADDR_READ		0x05
+#define DOC_CMD_READ_ALL_PLANES		0x30
+#define DOC_CMD_READ_PLANE2		0x50
+#define DOC_CMD_READ_FLASH		0xe0
+#define DOC_CMD_PAGE_SIZE_532		0x3c
+
+#define DOC_CMD_PROG_BLOCK_ADDR		0x60
+#define DOC_CMD_PROG_CYCLE1		0x80
+#define DOC_CMD_PROG_CYCLE2		0x10
+#define DOC_CMD_ERASECYCLE2		0xd0
+
+#define DOC_CMD_RELIABLE_MODE		0x22
+#define DOC_CMD_FAST_MODE		0xa2
+
+#define DOC_CMD_RESET			0xff
+
+/*
+ * Flash register : DOC_FLASHCONTROL
+ */
+#define DOC_CTRL_VIOLATION		0x20
+#define DOC_CTRL_CE			0x10
+#define DOC_CTRL_UNKNOWN_BITS		0x08
+#define DOC_CTRL_PROTECTION_ERROR	0x04
+#define DOC_CTRL_SEQUENCE_ERROR		0x02
+#define DOC_CTRL_FLASHREADY		0x01
+
+/*
+ * Flash register : DOC_ASICMODE
+ */
+#define DOC_ASICMODE_RESET		0x00
+#define DOC_ASICMODE_NORMAL		0x01
+#define DOC_ASICMODE_POWERDOWN		0x02
+#define DOC_ASICMODE_MDWREN		0x04
+#define DOC_ASICMODE_BDETCT_RESET	0x08
+#define DOC_ASICMODE_RSTIN_RESET	0x10
+#define DOC_ASICMODE_RAM_WE		0x20
+
+/*
+ * Flash register : DOC_ECCCONF0
+ */
+#define DOC_ECCCONF0_READ_MODE		0x8000
+#define DOC_ECCCONF0_AUTO_ECC_ENABLE	0x4000
+#define DOC_ECCCONF0_HAMMING_ENABLE	0x1000
+#define DOC_ECCCONF0_BCH_ENABLE		0x0800
+#define DOC_ECCCONF0_DATA_BYTES_MASK	0x07ff
+
+/*
+ * Flash register : DOC_ECCCONF1
+ */
+#define DOC_ECCCONF1_BCH_SYNDROM_ERR	0x80
+#define DOC_ECCCONF1_UNKOWN1		0x40
+#define DOC_ECCCONF1_UNKOWN2		0x20
+#define DOC_ECCCONF1_UNKOWN3		0x10
+#define DOC_ECCCONF1_HAMMING_BITS_MASK	0x0f
+
+/*
+ * Flash register : DOC_PROTECTION
+ */
+#define DOC_PROTECT_FOUNDRY_OTP_LOCK	0x01
+#define DOC_PROTECT_CUSTOMER_OTP_LOCK	0x02
+#define DOC_PROTECT_LOCK_INPUT		0x04
+#define DOC_PROTECT_STICKY_LOCK		0x08
+#define DOC_PROTECT_PROTECTION_ENABLED	0x10
+#define DOC_PROTECT_IPL_DOWNLOAD_LOCK	0x20
+#define DOC_PROTECT_PROTECTION_ERROR	0x80
+
+/*
+ * Flash register : DOC_DPS0_STATUS and DOC_DPS1_STATUS
+ */
+#define DOC_DPS_OTP_PROTECTED		0x01
+#define DOC_DPS_READ_PROTECTED		0x02
+#define DOC_DPS_WRITE_PROTECTED		0x04
+#define DOC_DPS_HW_LOCK_ENABLED		0x08
+#define DOC_DPS_KEY_OK			0x80
+
+/*
+ * Flash register : DOC_CONFIGURATION
+ */
+#define DOC_CONF_IF_CFG			0x80
+#define DOC_CONF_MAX_ID_MASK		0x30
+#define DOC_CONF_VCCQ_3V		0x01
+
+/*
+ * Flash register : DOC_READADDRESS
+ */
+#define DOC_READADDR_INC		0x8000
+#define DOC_READADDR_ONE_BYTE		0x4000
+#define DOC_READADDR_ADDR_MASK		0x1fff
+
+/**
+ * struct docg3 - DiskOnChip driver private data
+ * @dev: the device currently under control
+ * @base: mapped IO space
+ * @device_id: number of the cascaded DoCG3 device (0, 1, 2 or 3)
+ * @if_cfg: if true, reads are on 16bits, else reads are on 8bits
+ * @bbt: bad block table cache
+ * @debugfs_root: debugfs root node
+ */
+struct docg3 {
+	struct device *dev;
+	void __iomem *base;
+	unsigned int device_id:4;
+	unsigned int if_cfg:1;
+	int max_block;
+	u8 *bbt;
+	struct dentry *debugfs_root;
+};
+
+#define doc_err(fmt, arg...) dev_err(docg3->dev, (fmt), ## arg)
+#define doc_info(fmt, arg...) dev_info(docg3->dev, (fmt), ## arg)
+#define doc_dbg(fmt, arg...) dev_dbg(docg3->dev, (fmt), ## arg)
+#define doc_vdbg(fmt, arg...) dev_vdbg(docg3->dev, (fmt), ## arg)
+
+#define DEBUGFS_RO_ATTR(name, show_fct) \
+	static int name##_open(struct inode *inode, struct file *file) \
+	{ return single_open(file, show_fct, inode->i_private); }      \
+	static const struct file_operations name##_fops = { \
+		.owner = THIS_MODULE, \
+		.open = name##_open, \
+		.llseek = seq_lseek, \
+		.read = seq_read, \
+		.release = single_release \
+	};
+#endif
+
+/*
+ * Trace events part
+ */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM docg3
+
+#if !defined(_MTD_DOCG3_TRACE) || defined(TRACE_HEADER_MULTI_READ)
+#define _MTD_DOCG3_TRACE
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(docg3_io,
+	    TP_PROTO(int op, int width, u16 reg, int val),
+	    TP_ARGS(op, width, reg, val),
+	    TP_STRUCT__entry(
+		    __field(int, op)
+		    __field(unsigned char, width)
+		    __field(u16, reg)
+		    __field(int, val)),
+	    TP_fast_assign(
+		    __entry->op = op;
+		    __entry->width = width;
+		    __entry->reg = reg;
+		    __entry->val = val;),
+	    TP_printk("docg3: %s%02d reg=%04x, val=%04x",
+		      __entry->op ? "write" : "read", __entry->width,
+		      __entry->reg, __entry->val)
+	);
+#endif
+
+/* This part must be outside protection */
+#undef TRACE_INCLUDE_PATH
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE docg3
+#include <trace/define_trace.h>