at91: atmel_nand: Update driver to support Programmable Multibit ECC controller

The Programmable Multibit ECC (PMECC) controller is a programmable binary
BCH(Bose, Chaudhuri and Hocquenghem) encoder and decoder. This controller
can be used to support both SLC and MLC NAND Flash devices. It supports to
generate ECC to correct 2, 4, 8, 12 or 24 bits of error per sector of data.

To use PMECC in this driver, the user needs to set the PMECC correction
capability, the sector size and ROM lookup table offsets in board config file.

This driver is ported from Linux kernel atmel_nand PMECC patch. The main difference
is in this version it uses registers structure access hardware instead of using macros.
It is tested in 9x5 serial boards.

Signed-off-by: Josh Wu <josh.wu@atmel.com>
[rebase]
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>

1 files changed, 113 insertions, 0 deletions

diff --git a/drivers/mtd/nand/atmel_nand_ecc.h b/drivers/mtd/nand/atmel_nand_ecc.h
index 1ee7f993db..4732582e7f 100644
--- a/drivers/mtd/nand/atmel_nand_ecc.h
+++ b/drivers/mtd/nand/atmel_nand_ecc.h
@@ -33,4 +33,117 @@
 #define ATMEL_ECC_NPR		0x10			/* NParity register */
 #define		ATMEL_ECC_NPARITY	(0xffff << 0)		/* NParity */
 
+/* Register access macros for PMECC */
+#define pmecc_readl(addr, reg) \
+	readl(&addr->reg)
+
+#define pmecc_writel(addr, reg, value) \
+	writel((value), &addr->reg)
+
+/* PMECC Register Definitions */
+#define PMECC_MAX_SECTOR_NUM			8
+struct pmecc_regs {
+	u32 cfg;		/* 0x00 PMECC Configuration Register */
+	u32 sarea;		/* 0x04 PMECC Spare Area Size Register */
+	u32 saddr;		/* 0x08 PMECC Start Address Register */
+	u32 eaddr;		/* 0x0C PMECC End Address Register */
+	u32 clk;		/* 0x10 PMECC Clock Control Register */
+	u32 ctrl;		/* 0x14 PMECC Control Register */
+	u32 sr;			/* 0x18 PMECC Status Register */
+	u32 ier;		/* 0x1C PMECC Interrupt Enable Register */
+	u32 idr;		/* 0x20 PMECC Interrupt Disable Register */
+	u32 imr;		/* 0x24 PMECC Interrupt Mask Register */
+	u32 isr;		/* 0x28 PMECC Interrupt Status Register */
+	u32 reserved0[5];	/* 0x2C-0x3C Reserved */
+
+	/* 0x40 + sector_num * (0x40), Redundancy Registers */
+	struct {
+		u8 ecc[44];	/* PMECC Generated Redundancy Byte Per Sector */
+		u32 reserved1[5];
+	} ecc_port[PMECC_MAX_SECTOR_NUM];
+
+	/* 0x240 + sector_num * (0x40) Remainder Registers */
+	struct {
+		u32 rem[12];
+		u32 reserved2[4];
+	} rem_port[PMECC_MAX_SECTOR_NUM];
+	u32 reserved3[16];	/* 0x440-0x47C Reserved */
+};
+
+/* For PMECC Configuration Register */
+#define		PMECC_CFG_BCH_ERR2		(0 << 0)
+#define		PMECC_CFG_BCH_ERR4		(1 << 0)
+#define		PMECC_CFG_BCH_ERR8		(2 << 0)
+#define		PMECC_CFG_BCH_ERR12		(3 << 0)
+#define		PMECC_CFG_BCH_ERR24		(4 << 0)
+
+#define		PMECC_CFG_SECTOR512		(0 << 4)
+#define		PMECC_CFG_SECTOR1024		(1 << 4)
+
+#define		PMECC_CFG_PAGE_1SECTOR		(0 << 8)
+#define		PMECC_CFG_PAGE_2SECTORS		(1 << 8)
+#define		PMECC_CFG_PAGE_4SECTORS		(2 << 8)
+#define		PMECC_CFG_PAGE_8SECTORS		(3 << 8)
+
+#define		PMECC_CFG_READ_OP		(0 << 12)
+#define		PMECC_CFG_WRITE_OP		(1 << 12)
+
+#define		PMECC_CFG_SPARE_ENABLE		(1 << 16)
+#define		PMECC_CFG_SPARE_DISABLE		(0 << 16)
+
+#define		PMECC_CFG_AUTO_ENABLE		(1 << 20)
+#define		PMECC_CFG_AUTO_DISABLE		(0 << 20)
+
+/* For PMECC Clock Control Register */
+#define		PMECC_CLK_133MHZ		(2 << 0)
+
+/* For PMECC Control Register */
+#define		PMECC_CTRL_RST			(1 << 0)
+#define		PMECC_CTRL_DATA			(1 << 1)
+#define		PMECC_CTRL_USER			(1 << 2)
+#define		PMECC_CTRL_ENABLE		(1 << 4)
+#define		PMECC_CTRL_DISABLE		(1 << 5)
+
+/* For PMECC Status Register */
+#define		PMECC_SR_BUSY			(1 << 0)
+#define		PMECC_SR_ENABLE			(1 << 4)
+
+/* PMERRLOC Register Definitions */
+struct pmecc_errloc_regs {
+	u32 elcfg;	/* 0x00 Error Location Configuration Register */
+	u32 elprim;	/* 0x04 Error Location Primitive Register */
+	u32 elen;	/* 0x08 Error Location Enable Register */
+	u32 eldis;	/* 0x0C Error Location Disable Register */
+	u32 elsr;	/* 0x10 Error Location Status Register */
+	u32 elier;	/* 0x14 Error Location Interrupt Enable Register */
+	u32 elidr;	/* 0x08 Error Location Interrupt Disable Register */
+	u32 elimr;	/* 0x0C Error Location Interrupt Mask Register */
+	u32 elisr;	/* 0x20 Error Location Interrupt Status Register */
+	u32 reserved0;	/* 0x24 Reserved */
+	u32 sigma[25];	/* 0x28-0x88 Error Location Sigma Registers */
+	u32 el[24];	/* 0x8C-0xE8 Error Location Registers */
+	u32 reserved1[5];	/* 0xEC-0xFC Reserved */
+};
+
+/* For Error Location Configuration Register */
+#define		PMERRLOC_ELCFG_SECTOR_512	(0 << 0)
+#define		PMERRLOC_ELCFG_SECTOR_1024	(1 << 0)
+#define		PMERRLOC_ELCFG_NUM_ERRORS(n)	((n) << 16)
+
+/* For Error Location Disable Register */
+#define		PMERRLOC_DISABLE		(1 << 0)
+
+/* For Error Location Interrupt Status Register */
+#define		PMERRLOC_ERR_NUM_MASK		(0x1f << 8)
+#define		PMERRLOC_CALC_DONE		(1 << 0)
+
+/* Galois field dimension */
+#define PMECC_GF_DIMENSION_13			13
+#define PMECC_GF_DIMENSION_14			14
+
+#define PMECC_INDEX_TABLE_SIZE_512		0x2000
+#define PMECC_INDEX_TABLE_SIZE_1024		0x4000
+
+#define PMECC_MAX_TIMEOUT_US		(100 * 1000)
+
 #endif