* by the Free Software Foundation.
*
* Copyright © 2012 John Crispin <blogic@openwrt.org>
+ * Copyright © 2016 Hauke Mehrtens <hauke@hauke-m.de>
*/
#include <linux/mtd/nand.h>
#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 */
-#define NAND_CMD_ALE (1 << 2)
-#define NAND_CMD_CLE (1 << 3)
-#define NAND_CMD_CS (1 << 4)
-#define NAND_WRITE_CMD_RESET 0xff
+/*
+ * 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)
-#define NAND_WAIT_WR_C (1 << 3)
-#define NAND_WAIT_RD (0x1)
/* we need to tel the ebu which addr we mapped the nand to */
#define ADDSEL1_MASK(x) (x << 4)
#define NAND_CON_CSMUX (1 << 1)
#define NAND_CON_NANDM 1
-static void xway_reset_chip(struct nand_chip *chip)
+struct xway_nand_data {
+ struct nand_chip chip;
+ unsigned long csflags;
+ void __iomem *nandaddr;
+};
+
+static u8 xway_readb(struct mtd_info *mtd, int op)
{
- unsigned long nandaddr = (unsigned long) chip->IO_ADDR_W;
- unsigned long flags;
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct xway_nand_data *data = nand_get_controller_data(chip);
- nandaddr &= ~NAND_WRITE_ADDR;
- nandaddr |= NAND_WRITE_CMD;
+ return readb(data->nandaddr + op);
+}
- /* finish with a reset */
- spin_lock_irqsave(&ebu_lock, flags);
- writeb(NAND_WRITE_CMD_RESET, (void __iomem *) nandaddr);
- while ((ltq_ebu_r32(EBU_NAND_WAIT) & NAND_WAIT_WR_C) == 0)
- ;
- spin_unlock_irqrestore(&ebu_lock, flags);
+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 chip)
+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 (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;
static void xway_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
{
- struct nand_chip *this = mtd_to_nand(mtd);
- unsigned long nandaddr = (unsigned long) this->IO_ADDR_W;
- unsigned long flags;
-
- if (ctrl & NAND_CTRL_CHANGE) {
- nandaddr &= ~(NAND_WRITE_CMD | NAND_WRITE_ADDR);
- if (ctrl & NAND_CLE)
- nandaddr |= NAND_WRITE_CMD;
- else
- nandaddr |= NAND_WRITE_ADDR;
- this->IO_ADDR_W = (void __iomem *) nandaddr;
- }
+ if (cmd == NAND_CMD_NONE)
+ return;
- if (cmd != NAND_CMD_NONE) {
- spin_lock_irqsave(&ebu_lock, flags);
- writeb(cmd, this->IO_ADDR_W);
- while ((ltq_ebu_r32(EBU_NAND_WAIT) & NAND_WAIT_WR_C) == 0)
- ;
- spin_unlock_irqrestore(&ebu_lock, flags);
- }
+ 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)
static unsigned char xway_read_byte(struct mtd_info *mtd)
{
- struct nand_chip *this = mtd_to_nand(mtd);
- unsigned long nandaddr = (unsigned long) this->IO_ADDR_R;
- unsigned long flags;
- int ret;
+ return xway_readb(mtd, NAND_READ_DATA);
+}
+
+static void xway_read_buf(struct mtd_info *mtd, u_char *buf, int len)
+{
+ int i;
- spin_lock_irqsave(&ebu_lock, flags);
- ret = ltq_r8((void __iomem *)(nandaddr + NAND_READ_DATA));
- spin_unlock_irqrestore(&ebu_lock, flags);
+ for (i = 0; i < len; i++)
+ buf[i] = xway_readb(mtd, NAND_WRITE_DATA);
+}
- return ret;
+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 nand_chip *this = platform_get_drvdata(pdev);
- unsigned long nandaddr = (unsigned long) this->IO_ADDR_W;
- const __be32 *cs = of_get_property(pdev->dev.of_node,
- "lantiq,cs", NULL);
+ 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 */
- if (cs && (*cs == 1))
+ 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(nandaddr)
- | ADDSEL1_MASK(3) | ADDSEL1_REGEN, EBU_ADDSEL1);
+ 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);
+ | 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);
+ | NAND_CON_SE_P | NAND_CON_WP_P | NAND_CON_PRE_P
+ | cs_flag, EBU_NAND_CON);
- /* finish with a reset */
- xway_reset_chip(this);
+ /* Scan to find existence of the device */
+ err = nand_scan(mtd, 1);
+ if (err)
+ return err;
- return 0;
-}
+ err = mtd_device_register(mtd, NULL, 0);
+ if (err)
+ nand_release(mtd);
-static struct platform_nand_data xway_nand_data = {
- .chip = {
- .nr_chips = 1,
- .chip_delay = 30,
- },
- .ctrl = {
- .probe = xway_nand_probe,
- .cmd_ctrl = xway_cmd_ctrl,
- .dev_ready = xway_dev_ready,
- .select_chip = xway_select_chip,
- .read_byte = xway_read_byte,
- }
-};
+ return err;
+}
/*
- * Try to find the node inside the DT. If it is available attach out
- * platform_nand_data
+ * Remove a NAND device.
*/
-static int __init xway_register_nand(void)
+static int xway_nand_remove(struct platform_device *pdev)
{
- struct device_node *node;
- struct platform_device *pdev;
-
- node = of_find_compatible_node(NULL, NULL, "lantiq,nand-xway");
- if (!node)
- return -ENOENT;
- pdev = of_find_device_by_node(node);
- if (!pdev)
- return -EINVAL;
- pdev->dev.platform_data = &xway_nand_data;
- of_node_put(node);
+ struct xway_nand_data *data = platform_get_drvdata(pdev);
+
+ nand_release(nand_to_mtd(&data->chip));
+
return 0;
}
-subsys_initcall(xway_register_nand);
+static const struct of_device_id xway_nand_match[] = {
+ { .compatible = "lantiq,nand-xway" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, xway_nand_match);
+
+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,
+ },
+};
+
+module_platform_driver(xway_nand_driver);
+
+MODULE_LICENSE("GPL");
projects / deliverable / linux.git / blobdiff