1// SPDX-License-Identifier: GPL-2.0+ 2/* 3 * (C) Copyright 2008 4 * Sergei Poselenov, Emcraft Systems, sposelenov@emcraft.com. 5 */ 6 7#include <config.h> 8 9#if defined(CFG_SYS_NAND_BASE) 10#include <nand.h> 11#include <linux/errno.h> 12#include <linux/mtd/rawnand.h> 13#include <asm/io.h> 14 15static int state; 16static void sc_nand_write_byte(struct mtd_info *mtd, u_char byte); 17static void sc_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len); 18static u_char sc_nand_read_byte(struct mtd_info *mtd); 19static u16 sc_nand_read_word(struct mtd_info *mtd); 20static void sc_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len); 21static int sc_nand_device_ready(struct mtd_info *mtdinfo); 22 23#define FPGA_NAND_CMD_MASK (0x7 << 28) 24#define FPGA_NAND_CMD_COMMAND (0x0 << 28) 25#define FPGA_NAND_CMD_ADDR (0x1 << 28) 26#define FPGA_NAND_CMD_READ (0x2 << 28) 27#define FPGA_NAND_CMD_WRITE (0x3 << 28) 28#define FPGA_NAND_BUSY (0x1 << 15) 29#define FPGA_NAND_ENABLE (0x1 << 31) 30#define FPGA_NAND_DATA_SHIFT 16 31 32/** 33 * sc_nand_write_byte - write one byte to the chip 34 * @mtd: MTD device structure 35 * @byte: pointer to data byte to write 36 */ 37static void sc_nand_write_byte(struct mtd_info *mtd, u_char byte) 38{ 39 sc_nand_write_buf(mtd, (const uchar *)&byte, sizeof(byte)); 40} 41 42/** 43 * sc_nand_write_buf - write buffer to chip 44 * @mtd: MTD device structure 45 * @buf: data buffer 46 * @len: number of bytes to write 47 */ 48static void sc_nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len) 49{ 50 int i; 51 struct nand_chip *this = mtd_to_nand(mtd); 52 53 for (i = 0; i < len; i++) { 54 out_be32(this->IO_ADDR_W, 55 state | (buf[i] << FPGA_NAND_DATA_SHIFT)); 56 } 57} 58 59 60/** 61 * sc_nand_read_byte - read one byte from the chip 62 * @mtd: MTD device structure 63 */ 64static u_char sc_nand_read_byte(struct mtd_info *mtd) 65{ 66 u8 byte; 67 sc_nand_read_buf(mtd, (uchar *)&byte, sizeof(byte)); 68 return byte; 69} 70 71/** 72 * sc_nand_read_word - read one word from the chip 73 * @mtd: MTD device structure 74 */ 75static u16 sc_nand_read_word(struct mtd_info *mtd) 76{ 77 u16 word; 78 sc_nand_read_buf(mtd, (uchar *)&word, sizeof(word)); 79 return word; 80} 81 82/** 83 * sc_nand_read_buf - read chip data into buffer 84 * @mtd: MTD device structure 85 * @buf: buffer to store date 86 * @len: number of bytes to read 87 */ 88static void sc_nand_read_buf(struct mtd_info *mtd, u_char *buf, int len) 89{ 90 int i; 91 struct nand_chip *this = mtd_to_nand(mtd); 92 int val; 93 94 val = (state & FPGA_NAND_ENABLE) | FPGA_NAND_CMD_READ; 95 96 out_be32(this->IO_ADDR_W, val); 97 for (i = 0; i < len; i++) { 98 buf[i] = (in_be32(this->IO_ADDR_R) >> FPGA_NAND_DATA_SHIFT) & 0xff; 99 } 100} 101 102/** 103 * sc_nand_device_ready - Check the NAND device is ready for next command. 104 * @mtd: MTD device structure 105 */ 106static int sc_nand_device_ready(struct mtd_info *mtdinfo) 107{ 108 struct nand_chip *this = mtd_to_nand(mtdinfo); 109 110 if (in_be32(this->IO_ADDR_W) & FPGA_NAND_BUSY) 111 return 0; /* busy */ 112 return 1; 113} 114 115/** 116 * sc_nand_hwcontrol - NAND control functions wrapper. 117 * @mtd: MTD device structure 118 * @cmd: Command 119 */ 120static void sc_nand_hwcontrol(struct mtd_info *mtdinfo, int cmd, unsigned int ctrl) 121{ 122 if (ctrl & NAND_CTRL_CHANGE) { 123 state &= ~(FPGA_NAND_CMD_MASK | FPGA_NAND_ENABLE); 124 125 switch (ctrl & (NAND_ALE | NAND_CLE)) { 126 case 0: 127 state |= FPGA_NAND_CMD_WRITE; 128 break; 129 130 case NAND_ALE: 131 state |= FPGA_NAND_CMD_ADDR; 132 break; 133 134 case NAND_CLE: 135 state |= FPGA_NAND_CMD_COMMAND; 136 break; 137 138 default: 139 printf("%s: unknown ctrl %#x\n", __FUNCTION__, ctrl); 140 } 141 142 if (ctrl & NAND_NCE) 143 state |= FPGA_NAND_ENABLE; 144 } 145 146 if (cmd != NAND_CMD_NONE) 147 sc_nand_write_byte(mtdinfo, cmd); 148} 149 150int board_nand_init(struct nand_chip *nand) 151{ 152 nand->cmd_ctrl = sc_nand_hwcontrol; 153 nand->ecc.mode = NAND_ECC_SOFT; 154 nand->dev_ready = sc_nand_device_ready; 155 nand->read_byte = sc_nand_read_byte; 156 nand->read_word = sc_nand_read_word; 157 nand->write_buf = sc_nand_write_buf; 158 nand->read_buf = sc_nand_read_buf; 159 160 return 0; 161} 162 163#endif 164