mtd: add bcmring nand driver

Signed-off-by: Leo Hao Chen <leochen@broadcom.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/nand/nand_bcm_umi.h b/drivers/mtd/nand/nand_bcm_umi.h
new file mode 100644
index 0000000..7cec2cd
--- /dev/null
+++ b/drivers/mtd/nand/nand_bcm_umi.h
@@ -0,0 +1,358 @@
+/*****************************************************************************
+* Copyright 2003 - 2009 Broadcom Corporation.  All rights reserved.
+*
+* Unless you and Broadcom execute a separate written software license
+* agreement governing use of this software, this software is licensed to you
+* under the terms of the GNU General Public License version 2, available at
+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
+*
+* Notwithstanding the above, under no circumstances may you combine this
+* software in any way with any other Broadcom software provided under a
+* license other than the GPL, without Broadcom's express prior written
+* consent.
+*****************************************************************************/
+#ifndef NAND_BCM_UMI_H
+#define NAND_BCM_UMI_H
+
+/* ---- Include Files ---------------------------------------------------- */
+#include <mach/reg_umi.h>
+#include <mach/reg_nand.h>
+#include <cfg_global.h>
+
+/* ---- Constants and Types ---------------------------------------------- */
+#if (CFG_GLOBAL_CHIP_FAMILY == CFG_GLOBAL_CHIP_FAMILY_BCMRING)
+#define NAND_ECC_BCH (CFG_GLOBAL_CHIP_REV > 0xA0)
+#else
+#define NAND_ECC_BCH 0
+#endif
+
+#define CFG_GLOBAL_NAND_ECC_BCH_NUM_BYTES	13
+
+#if NAND_ECC_BCH
+#ifdef BOOT0_BUILD
+#define NAND_ECC_NUM_BYTES 13
+#else
+#define NAND_ECC_NUM_BYTES CFG_GLOBAL_NAND_ECC_BCH_NUM_BYTES
+#endif
+#else
+#define NAND_ECC_NUM_BYTES 3
+#endif
+
+#define NAND_DATA_ACCESS_SIZE 512
+
+/* ---- Variable Externs ------------------------------------------ */
+/* ---- Function Prototypes --------------------------------------- */
+int nand_bcm_umi_bch_correct_page(uint8_t *datap, uint8_t *readEccData,
+				  int numEccBytes);
+
+/* Check in device is ready */
+static inline int nand_bcm_umi_dev_ready(void)
+{
+	return REG_UMI_NAND_RCSR & REG_UMI_NAND_RCSR_RDY;
+}
+
+/* Wait until device is ready */
+static inline void nand_bcm_umi_wait_till_ready(void)
+{
+	while (nand_bcm_umi_dev_ready() == 0)
+		;
+}
+
+/* Enable Hamming ECC */
+static inline void nand_bcm_umi_hamming_enable_hwecc(void)
+{
+	/* disable and reset ECC, 512 byte page */
+	REG_UMI_NAND_ECC_CSR &= ~(REG_UMI_NAND_ECC_CSR_ECC_ENABLE |
+		REG_UMI_NAND_ECC_CSR_256BYTE);
+	/* enable ECC */
+	REG_UMI_NAND_ECC_CSR |= REG_UMI_NAND_ECC_CSR_ECC_ENABLE;
+}
+
+#if NAND_ECC_BCH
+/* BCH ECC specifics */
+#define ECC_BITS_PER_CORRECTABLE_BIT 13
+
+/* Enable BCH Read ECC */
+static inline void nand_bcm_umi_bch_enable_read_hwecc(void)
+{
+	/* disable and reset ECC */
+	REG_UMI_BCH_CTRL_STATUS = REG_UMI_BCH_CTRL_STATUS_RD_ECC_VALID;
+	/* Turn on ECC */
+	REG_UMI_BCH_CTRL_STATUS = REG_UMI_BCH_CTRL_STATUS_ECC_RD_EN;
+}
+
+/* Enable BCH Write ECC */
+static inline void nand_bcm_umi_bch_enable_write_hwecc(void)
+{
+	/* disable and reset ECC */
+	REG_UMI_BCH_CTRL_STATUS = REG_UMI_BCH_CTRL_STATUS_WR_ECC_VALID;
+	/* Turn on ECC */
+	REG_UMI_BCH_CTRL_STATUS = REG_UMI_BCH_CTRL_STATUS_ECC_WR_EN;
+}
+
+/* Config number of BCH ECC bytes */
+static inline void nand_bcm_umi_bch_config_ecc(uint8_t numEccBytes)
+{
+	uint32_t nValue;
+	uint32_t tValue;
+	uint32_t kValue;
+	uint32_t numBits = numEccBytes * 8;
+
+	/* disable and reset ECC */
+	REG_UMI_BCH_CTRL_STATUS =
+	    REG_UMI_BCH_CTRL_STATUS_WR_ECC_VALID |
+	    REG_UMI_BCH_CTRL_STATUS_RD_ECC_VALID;
+
+	/* Every correctible bit requires 13 ECC bits */
+	tValue = (uint32_t) (numBits / ECC_BITS_PER_CORRECTABLE_BIT);
+
+	/* Total data in number of bits for generating and computing BCH ECC */
+	nValue = (NAND_DATA_ACCESS_SIZE + numEccBytes) * 8;
+
+	/* K parameter is used internally.  K = N - (T * 13) */
+	kValue = nValue - (tValue * ECC_BITS_PER_CORRECTABLE_BIT);
+
+	/* Write the settings */
+	REG_UMI_BCH_N = nValue;
+	REG_UMI_BCH_T = tValue;
+	REG_UMI_BCH_K = kValue;
+}
+
+/* Pause during ECC read calculation to skip bytes in OOB */
+static inline void nand_bcm_umi_bch_pause_read_ecc_calc(void)
+{
+	REG_UMI_BCH_CTRL_STATUS =
+	    REG_UMI_BCH_CTRL_STATUS_ECC_RD_EN |
+	    REG_UMI_BCH_CTRL_STATUS_PAUSE_ECC_DEC;
+}
+
+/* Resume during ECC read calculation after skipping bytes in OOB */
+static inline void nand_bcm_umi_bch_resume_read_ecc_calc(void)
+{
+	REG_UMI_BCH_CTRL_STATUS = REG_UMI_BCH_CTRL_STATUS_ECC_RD_EN;
+}
+
+/* Poll read ECC calc to check when hardware completes */
+static inline uint32_t nand_bcm_umi_bch_poll_read_ecc_calc(void)
+{
+	uint32_t regVal;
+
+	do {
+		/* wait for ECC to be valid */
+		regVal = REG_UMI_BCH_CTRL_STATUS;
+	} while ((regVal & REG_UMI_BCH_CTRL_STATUS_RD_ECC_VALID) == 0);
+
+	return regVal;
+}
+
+/* Poll write ECC calc to check when hardware completes */
+static inline void nand_bcm_umi_bch_poll_write_ecc_calc(void)
+{
+	/* wait for ECC to be valid */
+	while ((REG_UMI_BCH_CTRL_STATUS & REG_UMI_BCH_CTRL_STATUS_WR_ECC_VALID)
+	       == 0)
+		;
+}
+
+/* Read the OOB and ECC, for kernel write OOB to a buffer */
+#if defined(__KERNEL__) && !defined(STANDALONE)
+static inline void nand_bcm_umi_bch_read_oobEcc(uint32_t pageSize,
+	uint8_t *eccCalc, int numEccBytes, uint8_t *oobp)
+#else
+static inline void nand_bcm_umi_bch_read_oobEcc(uint32_t pageSize,
+	uint8_t *eccCalc, int numEccBytes)
+#endif
+{
+	int eccPos = 0;
+	int numToRead = 16;	/* There are 16 bytes per sector in the OOB */
+
+	/* ECC is already paused when this function is called */
+
+	if (pageSize == NAND_DATA_ACCESS_SIZE) {
+		while (numToRead > numEccBytes) {
+			/* skip free oob region */
+#if defined(__KERNEL__) && !defined(STANDALONE)
+			*oobp++ = REG_NAND_DATA8;
+#else
+			REG_NAND_DATA8;
+#endif
+			numToRead--;
+		}
+
+		/* read ECC bytes before BI */
+		nand_bcm_umi_bch_resume_read_ecc_calc();
+
+		while (numToRead > 11) {
+#if defined(__KERNEL__) && !defined(STANDALONE)
+			*oobp = REG_NAND_DATA8;
+			eccCalc[eccPos++] = *oobp;
+			oobp++;
+#else
+			eccCalc[eccPos++] = REG_NAND_DATA8;
+#endif
+		}
+
+		nand_bcm_umi_bch_pause_read_ecc_calc();
+
+		if (numToRead == 11) {
+			/* read BI */
+#if defined(__KERNEL__) && !defined(STANDALONE)
+			*oobp++ = REG_NAND_DATA8;
+#else
+			REG_NAND_DATA8;
+#endif
+			numToRead--;
+		}
+
+		/* read ECC bytes */
+		nand_bcm_umi_bch_resume_read_ecc_calc();
+		while (numToRead) {
+#if defined(__KERNEL__) && !defined(STANDALONE)
+			*oobp = REG_NAND_DATA8;
+			eccCalc[eccPos++] = *oobp;
+			oobp++;
+#else
+			eccCalc[eccPos++] = REG_NAND_DATA8;
+#endif
+			numToRead--;
+		}
+	} else {
+		/* skip BI */
+#if defined(__KERNEL__) && !defined(STANDALONE)
+		*oobp++ = REG_NAND_DATA8;
+#else
+		REG_NAND_DATA8;
+#endif
+		numToRead--;
+
+		while (numToRead > numEccBytes) {
+			/* skip free oob region */
+#if defined(__KERNEL__) && !defined(STANDALONE)
+			*oobp++ = REG_NAND_DATA8;
+#else
+			REG_NAND_DATA8;
+#endif
+			numToRead--;
+		}
+
+		/* read ECC bytes */
+		nand_bcm_umi_bch_resume_read_ecc_calc();
+		while (numToRead) {
+#if defined(__KERNEL__) && !defined(STANDALONE)
+			*oobp = REG_NAND_DATA8;
+			eccCalc[eccPos++] = *oobp;
+			oobp++;
+#else
+			eccCalc[eccPos++] = REG_NAND_DATA8;
+#endif
+			numToRead--;
+		}
+	}
+}
+
+/* Helper function to write ECC */
+static inline void NAND_BCM_UMI_ECC_WRITE(int numEccBytes, int eccBytePos,
+					  uint8_t *oobp, uint8_t eccVal)
+{
+	if (eccBytePos <= numEccBytes)
+		*oobp = eccVal;
+}
+
+/* Write OOB with ECC */
+static inline void nand_bcm_umi_bch_write_oobEcc(uint32_t pageSize,
+						 uint8_t *oobp, int numEccBytes)
+{
+	uint32_t eccVal = 0xffffffff;
+
+	/* wait for write ECC to be valid */
+	nand_bcm_umi_bch_poll_write_ecc_calc();
+
+	/*
+	 ** Get the hardware ecc from the 32-bit result registers.
+	 ** Read after 512 byte accesses. Format B3B2B1B0
+	 ** where B3 = ecc3, etc.
+	 */
+
+	if (pageSize == NAND_DATA_ACCESS_SIZE) {
+		/* Now fill in the ECC bytes */
+		if (numEccBytes >= 13)
+			eccVal = REG_UMI_BCH_WR_ECC_3;
+
+		/* Usually we skip CM in oob[0,1] */
+		NAND_BCM_UMI_ECC_WRITE(numEccBytes, 15, &oobp[0],
+			(eccVal >> 16) & 0xff);
+		NAND_BCM_UMI_ECC_WRITE(numEccBytes, 14, &oobp[1],
+			(eccVal >> 8) & 0xff);
+
+		/* Write ECC in oob[2,3,4] */
+		NAND_BCM_UMI_ECC_WRITE(numEccBytes, 13, &oobp[2],
+			eccVal & 0xff);	/* ECC 12 */
+
+		if (numEccBytes >= 9)
+			eccVal = REG_UMI_BCH_WR_ECC_2;
+
+		NAND_BCM_UMI_ECC_WRITE(numEccBytes, 12, &oobp[3],
+			(eccVal >> 24) & 0xff);	/* ECC11 */
+		NAND_BCM_UMI_ECC_WRITE(numEccBytes, 11, &oobp[4],
+			(eccVal >> 16) & 0xff);	/* ECC10 */
+
+		/* Always Skip BI in oob[5] */
+	} else {
+		/* Always Skip BI in oob[0] */
+
+		/* Now fill in the ECC bytes */
+		if (numEccBytes >= 13)
+			eccVal = REG_UMI_BCH_WR_ECC_3;
+
+		/* Usually skip CM in oob[1,2] */
+		NAND_BCM_UMI_ECC_WRITE(numEccBytes, 15, &oobp[1],
+			(eccVal >> 16) & 0xff);
+		NAND_BCM_UMI_ECC_WRITE(numEccBytes, 14, &oobp[2],
+			(eccVal >> 8) & 0xff);
+
+		/* Write ECC in oob[3-15] */
+		NAND_BCM_UMI_ECC_WRITE(numEccBytes, 13, &oobp[3],
+			eccVal & 0xff);	/* ECC12 */
+
+		if (numEccBytes >= 9)
+			eccVal = REG_UMI_BCH_WR_ECC_2;
+
+		NAND_BCM_UMI_ECC_WRITE(numEccBytes, 12, &oobp[4],
+			(eccVal >> 24) & 0xff);	/* ECC11 */
+		NAND_BCM_UMI_ECC_WRITE(numEccBytes, 11, &oobp[5],
+			(eccVal >> 16) & 0xff);	/* ECC10 */
+	}
+
+	/* Fill in the remainder of ECC locations */
+	NAND_BCM_UMI_ECC_WRITE(numEccBytes, 10, &oobp[6],
+		(eccVal >> 8) & 0xff);	/* ECC9 */
+	NAND_BCM_UMI_ECC_WRITE(numEccBytes, 9, &oobp[7],
+		eccVal & 0xff);	/* ECC8 */
+
+	if (numEccBytes >= 5)
+		eccVal = REG_UMI_BCH_WR_ECC_1;
+
+	NAND_BCM_UMI_ECC_WRITE(numEccBytes, 8, &oobp[8],
+		(eccVal >> 24) & 0xff);	/* ECC7 */
+	NAND_BCM_UMI_ECC_WRITE(numEccBytes, 7, &oobp[9],
+		(eccVal >> 16) & 0xff);	/* ECC6 */
+	NAND_BCM_UMI_ECC_WRITE(numEccBytes, 6, &oobp[10],
+		(eccVal >> 8) & 0xff);	/* ECC5 */
+	NAND_BCM_UMI_ECC_WRITE(numEccBytes, 5, &oobp[11],
+		eccVal & 0xff);	/* ECC4 */
+
+	if (numEccBytes >= 1)
+		eccVal = REG_UMI_BCH_WR_ECC_0;
+
+	NAND_BCM_UMI_ECC_WRITE(numEccBytes, 4, &oobp[12],
+		(eccVal >> 24) & 0xff);	/* ECC3 */
+	NAND_BCM_UMI_ECC_WRITE(numEccBytes, 3, &oobp[13],
+		(eccVal >> 16) & 0xff);	/* ECC2 */
+	NAND_BCM_UMI_ECC_WRITE(numEccBytes, 2, &oobp[14],
+		(eccVal >> 8) & 0xff);	/* ECC1 */
+	NAND_BCM_UMI_ECC_WRITE(numEccBytes, 1, &oobp[15],
+		eccVal & 0xff);	/* ECC0 */
+}
+#endif
+
+#endif /* NAND_BCM_UMI_H */