diff options
Diffstat (limited to 'arch/arm/mach-omap2/gpmc-nand.c')
| -rw-r--r-- | arch/arm/mach-omap2/gpmc-nand.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/gpmc-nand.c b/arch/arm/mach-omap2/gpmc-nand.c new file mode 100644 index 000000000..72918c497 --- /dev/null +++ b/arch/arm/mach-omap2/gpmc-nand.c @@ -0,0 +1,159 @@ +/* + * gpmc-nand.c + * + * Copyright (C) 2009 Texas Instruments + * Vimal Singh <vimalsingh@ti.com> + * + * 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. + */ + +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/omap-gpmc.h> +#include <linux/mtd/nand.h> +#include <linux/platform_data/mtd-nand-omap2.h> + +#include <asm/mach/flash.h> + +#include "soc.h" + +/* minimum size for IO mapping */ +#define NAND_IO_SIZE 4 + +static bool gpmc_hwecc_bch_capable(enum omap_ecc ecc_opt) +{ + /* platforms which support all ECC schemes */ + if (soc_is_am33xx() || soc_is_am43xx() || cpu_is_omap44xx() || + soc_is_omap54xx() || soc_is_dra7xx()) + return 1; + + if (ecc_opt == OMAP_ECC_BCH4_CODE_HW_DETECTION_SW || + ecc_opt == OMAP_ECC_BCH8_CODE_HW_DETECTION_SW) { + if (cpu_is_omap24xx()) + return 0; + else if (cpu_is_omap3630() && (GET_OMAP_REVISION() == 0)) + return 0; + else + return 1; + } + + /* OMAP3xxx do not have ELM engine, so cannot support ECC schemes + * which require H/W based ECC error detection */ + if ((cpu_is_omap34xx() || cpu_is_omap3630()) && + ((ecc_opt == OMAP_ECC_BCH4_CODE_HW) || + (ecc_opt == OMAP_ECC_BCH8_CODE_HW))) + return 0; + + /* legacy platforms support only HAM1 (1-bit Hamming) ECC scheme */ + if (ecc_opt == OMAP_ECC_HAM1_CODE_HW || + ecc_opt == OMAP_ECC_HAM1_CODE_SW) + return 1; + else + return 0; +} + +/* This function will go away once the device-tree convertion is complete */ +static void gpmc_set_legacy(struct omap_nand_platform_data *gpmc_nand_data, + struct gpmc_settings *s) +{ + /* Enable RD PIN Monitoring Reg */ + if (gpmc_nand_data->dev_ready) { + s->wait_on_read = true; + s->wait_on_write = true; + } + + if (gpmc_nand_data->devsize == NAND_BUSWIDTH_16) + s->device_width = GPMC_DEVWIDTH_16BIT; + else + s->device_width = GPMC_DEVWIDTH_8BIT; +} + +int gpmc_nand_init(struct omap_nand_platform_data *gpmc_nand_data, + struct gpmc_timings *gpmc_t) +{ + int err = 0; + struct gpmc_settings s; + struct platform_device *pdev; + struct resource gpmc_nand_res[] = { + { .flags = IORESOURCE_MEM, }, + { .flags = IORESOURCE_IRQ, }, + { .flags = IORESOURCE_IRQ, }, + }; + + BUG_ON(gpmc_nand_data->cs >= GPMC_CS_NUM); + + err = gpmc_cs_request(gpmc_nand_data->cs, NAND_IO_SIZE, + (unsigned long *)&gpmc_nand_res[0].start); + if (err < 0) { + pr_err("omap2-gpmc: Cannot request GPMC CS %d, error %d\n", + gpmc_nand_data->cs, err); + return err; + } + gpmc_nand_res[0].end = gpmc_nand_res[0].start + NAND_IO_SIZE - 1; + gpmc_nand_res[1].start = gpmc_get_client_irq(GPMC_IRQ_FIFOEVENTENABLE); + gpmc_nand_res[2].start = gpmc_get_client_irq(GPMC_IRQ_COUNT_EVENT); + + memset(&s, 0, sizeof(struct gpmc_settings)); + if (gpmc_nand_data->of_node) + gpmc_read_settings_dt(gpmc_nand_data->of_node, &s); + else + gpmc_set_legacy(gpmc_nand_data, &s); + + s.device_nand = true; + + if (gpmc_t) { + err = gpmc_cs_set_timings(gpmc_nand_data->cs, gpmc_t, &s); + if (err < 0) { + pr_err("omap2-gpmc: Unable to set gpmc timings: %d\n", + err); + return err; + } + } + + err = gpmc_cs_program_settings(gpmc_nand_data->cs, &s); + if (err < 0) + goto out_free_cs; + + err = gpmc_configure(GPMC_CONFIG_WP, 0); + if (err < 0) + goto out_free_cs; + + gpmc_update_nand_reg(&gpmc_nand_data->reg, gpmc_nand_data->cs); + + if (!gpmc_hwecc_bch_capable(gpmc_nand_data->ecc_opt)) { + pr_err("omap2-nand: Unsupported NAND ECC scheme selected\n"); + err = -EINVAL; + goto out_free_cs; + } + + + pdev = platform_device_alloc("omap2-nand", gpmc_nand_data->cs); + if (pdev) { + err = platform_device_add_resources(pdev, gpmc_nand_res, + ARRAY_SIZE(gpmc_nand_res)); + if (!err) + pdev->dev.platform_data = gpmc_nand_data; + } else { + err = -ENOMEM; + } + if (err) + goto out_free_pdev; + + err = platform_device_add(pdev); + if (err) { + dev_err(&pdev->dev, "Unable to register NAND device\n"); + goto out_free_pdev; + } + + return 0; + +out_free_pdev: + platform_device_put(pdev); +out_free_cs: + gpmc_cs_free(gpmc_nand_data->cs); + + return err; +} |