/* * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published * by the Free Software Foundation. * * Copyright © 2012 John Crispin * Copyright © 2016 Hauke Mehrtens */ #include #include #include #include /* nand registers */ #define EBU_ADDSEL1 0x24 #define EBU_NAND_CON 0xB0 #define EBU_NAND_WAIT 0xB4 #define NAND_WAIT_RD BIT(0) /* NAND flash status output */ #define NAND_WAIT_WR_C BIT(3) /* NAND Write/Read complete */ #define EBU_NAND_ECC0 0xB8 #define EBU_NAND_ECC_AC 0xBC /* * nand commands * The pins of the NAND chip are selected based on the address bits of the * "register" read and write. There are no special registers, but an * address range and the lower address bits are used to activate the * correct line. For example when the bit (1 << 2) is set in the address * the ALE pin will be activated. */ #define NAND_CMD_ALE BIT(2) /* address latch enable */ #define NAND_CMD_CLE BIT(3) /* command latch enable */ #define NAND_CMD_CS BIT(4) /* chip select */ #define NAND_CMD_SE BIT(5) /* spare area access latch */ #define NAND_CMD_WP BIT(6) /* write protect */ #define NAND_WRITE_CMD (NAND_CMD_CS | NAND_CMD_CLE) #define NAND_WRITE_ADDR (NAND_CMD_CS | NAND_CMD_ALE) #define NAND_WRITE_DATA (NAND_CMD_CS) #define NAND_READ_DATA (NAND_CMD_CS) /* we need to tel the ebu which addr we mapped the nand to */ #define ADDSEL1_MASK(x) (x << 4) #define ADDSEL1_REGEN 1 /* we need to tell the EBU that we have nand attached and set it up properly */ #define BUSCON1_SETUP (1 << 22) #define BUSCON1_BCGEN_RES (0x3 << 12) #define BUSCON1_WAITWRC2 (2 << 8) #define BUSCON1_WAITRDC2 (2 << 6) #define BUSCON1_HOLDC1 (1 << 4) #define BUSCON1_RECOVC1 (1 << 2) #define BUSCON1_CMULT4 1 #define NAND_CON_CE (1 << 20) #define NAND_CON_OUT_CS1 (1 << 10) #define NAND_CON_IN_CS1 (1 << 8) #define NAND_CON_PRE_P (1 << 7) #define NAND_CON_WP_P (1 << 6) #define NAND_CON_SE_P (1 << 5) #define NAND_CON_CS_P (1 << 4) #define NAND_CON_CSMUX (1 << 1) #define NAND_CON_NANDM 1 struct xway_nand_data { struct nand_chip chip; unsigned long csflags; void __iomem *nandaddr; }; static u8 xway_readb(struct mtd_info *mtd, int op) { struct nand_chip *chip = mtd_to_nand(mtd); struct xway_nand_data *data = nand_get_controller_data(chip); return readb(data->nandaddr + op); } static void xway_writeb(struct mtd_info *mtd, int op, u8 value) { struct nand_chip *chip = mtd_to_nand(mtd); struct xway_nand_data *data = nand_get_controller_data(chip); writeb(value, data->nandaddr + op); } static void xway_select_chip(struct mtd_info *mtd, int select) { struct nand_chip *chip = mtd_to_nand(mtd); struct xway_nand_data *data = nand_get_controller_data(chip); switch (select) { case -1: ltq_ebu_w32_mask(NAND_CON_CE, 0, EBU_NAND_CON); ltq_ebu_w32_mask(NAND_CON_NANDM, 0, EBU_NAND_CON); spin_unlock_irqrestore(&ebu_lock, data->csflags); break; case 0: spin_lock_irqsave(&ebu_lock, data->csflags); ltq_ebu_w32_mask(0, NAND_CON_NANDM, EBU_NAND_CON); ltq_ebu_w32_mask(0, NAND_CON_CE, EBU_NAND_CON); break; default: BUG(); } } static void xway_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl) { if (cmd == NAND_CMD_NONE) return; if (ctrl & NAND_CLE) xway_writeb(mtd, NAND_WRITE_CMD, cmd); else if (ctrl & NAND_ALE) xway_writeb(mtd, NAND_WRITE_ADDR, cmd); while ((ltq_ebu_r32(EBU_NAND_WAIT) & NAND_WAIT_WR_C) == 0) ; } static int xway_dev_ready(struct mtd_info *mtd) { return ltq_ebu_r32(EBU_NAND_WAIT) & NAND_WAIT_RD; } static unsigned char xway_read_byte(struct mtd_info *mtd) { return xway_readb(mtd, NAND_READ_DATA); } static void xway_read_buf(struct mtd_info *mtd, u_char *buf, int len) { int i; for (i = 0; i < len; i++) buf[i] = xway_readb(mtd, NAND_WRITE_DATA); } static void xway_write_buf(struct mtd_info *mtd, const u_char *buf, int len) { int i; for (i = 0; i < len; i++) xway_writeb(mtd, NAND_WRITE_DATA, buf[i]); } /* * Probe for the NAND device. */ static int xway_nand_probe(struct platform_device *pdev) { struct xway_nand_data *data; struct mtd_info *mtd; struct resource *res; int err; u32 cs; u32 cs_flag = 0; /* Allocate memory for the device structure (and zero it) */ data = devm_kzalloc(&pdev->dev, sizeof(struct xway_nand_data), GFP_KERNEL); if (!data) return -ENOMEM; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); data->nandaddr = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(data->nandaddr)) return PTR_ERR(data->nandaddr); nand_set_flash_node(&data->chip, pdev->dev.of_node); mtd = nand_to_mtd(&data->chip); mtd->dev.parent = &pdev->dev; data->chip.cmd_ctrl = xway_cmd_ctrl; data->chip.dev_ready = xway_dev_ready; data->chip.select_chip = xway_select_chip; data->chip.write_buf = xway_write_buf; data->chip.read_buf = xway_read_buf; data->chip.read_byte = xway_read_byte; data->chip.chip_delay = 30; data->chip.ecc.mode = NAND_ECC_SOFT; data->chip.ecc.algo = NAND_ECC_HAMMING; platform_set_drvdata(pdev, data); nand_set_controller_data(&data->chip, data); /* load our CS from the DT. Either we find a valid 1 or default to 0 */ err = of_property_read_u32(pdev->dev.of_node, "lantiq,cs", &cs); if (!err && cs == 1) cs_flag = NAND_CON_IN_CS1 | NAND_CON_OUT_CS1; /* setup the EBU to run in NAND mode on our base addr */ ltq_ebu_w32(CPHYSADDR(data->nandaddr) | ADDSEL1_MASK(3) | ADDSEL1_REGEN, EBU_ADDSEL1); ltq_ebu_w32(BUSCON1_SETUP | BUSCON1_BCGEN_RES | BUSCON1_WAITWRC2 | BUSCON1_WAITRDC2 | BUSCON1_HOLDC1 | BUSCON1_RECOVC1 | BUSCON1_CMULT4, LTQ_EBU_BUSCON1); ltq_ebu_w32(NAND_CON_NANDM | NAND_CON_CSMUX | NAND_CON_CS_P | NAND_CON_SE_P | NAND_CON_WP_P | NAND_CON_PRE_P | cs_flag, EBU_NAND_CON); /* Scan to find existence of the device */ err = nand_scan(&data->chip, 1); if (err) return err; err = mtd_device_register(mtd, NULL, 0); if (err) nand_cleanup(&data->chip); return err; } /* * Remove a NAND device. */ static int xway_nand_remove(struct platform_device *pdev) { struct xway_nand_data *data = platform_get_drvdata(pdev); nand_release(&data->chip); return 0; } static const struct of_device_id xway_nand_match[] = { { .compatible = "lantiq,nand-xway" }, {}, }; static struct platform_driver xway_nand_driver = { .probe = xway_nand_probe, .remove = xway_nand_remove, .driver = { .name = "lantiq,nand-xway", .of_match_table = xway_nand_match, }, }; builtin_platform_driver(xway_nand_driver);