From d5814bdb661d3dac61422f8f69e459be884c9a9d Mon Sep 17 00:00:00 2001 From: Maarten ter Huurne Date: Tue, 2 Aug 2011 10:49:28 +0200 Subject: [PATCH 06/21] MTD: NAND: JZ4740: Multi-bank support with autodetection The platform data can now specify which external memory banks to probe for NAND chips, and in which order. Banks that contain a NAND are used and the other banks are freed. Squashed version of development done in jz-2.6.38 branch. Original patch by Lars-Peter Clausen with some bug fixes from me. Thanks to Paul Cercueil for the initial autodetection patch. --- arch/mips/include/asm/mach-jz4740/jz4740_nand.h | 4 + arch/mips/jz4740/platform.c | 20 ++- drivers/mtd/nand/jz4740_nand.c | 228 +++++++++++++++++++---- 3 files changed, 215 insertions(+), 37 deletions(-) --- a/arch/mips/include/asm/mach-jz4740/jz4740_nand.h +++ b/arch/mips/include/asm/mach-jz4740/jz4740_nand.h @@ -19,6 +19,8 @@ #include #include +#define JZ_NAND_NUM_BANKS 4 + struct jz_nand_platform_data { int num_partitions; struct mtd_partition *partitions; @@ -27,6 +29,8 @@ struct jz_nand_platform_data { unsigned int busy_gpio; + unsigned char banks[JZ_NAND_NUM_BANKS]; + void (*ident_callback)(struct platform_device *, struct nand_chip *, struct mtd_partition **, int *num_partitions); }; --- a/arch/mips/jz4740/platform.c +++ b/arch/mips/jz4740/platform.c @@ -157,11 +157,29 @@ static struct resource jz4740_nand_resou .flags = IORESOURCE_MEM, }, { - .name = "bank", + .name = "bank1", .start = 0x18000000, .end = 0x180C0000 - 1, .flags = IORESOURCE_MEM, }, + { + .name = "bank2", + .start = 0x14000000, + .end = 0x140C0000 - 1, + .flags = IORESOURCE_MEM, + }, + { + .name = "bank3", + .start = 0x0C000000, + .end = 0x0C0C0000 - 1, + .flags = IORESOURCE_MEM, + }, + { + .name = "bank4", + .start = 0x08000000, + .end = 0x080C0000 - 1, + .flags = IORESOURCE_MEM, + }, }; struct platform_device jz4740_nand_device = { --- a/drivers/mtd/nand/jz4740_nand.c +++ b/drivers/mtd/nand/jz4740_nand.c @@ -52,9 +52,10 @@ #define JZ_NAND_CTRL_ENABLE_CHIP(x) BIT((x) << 1) #define JZ_NAND_CTRL_ASSERT_CHIP(x) BIT(((x) << 1) + 1) +#define JZ_NAND_CTRL_ASSERT_CHIP_MASK 0xaa -#define JZ_NAND_MEM_ADDR_OFFSET 0x10000 #define JZ_NAND_MEM_CMD_OFFSET 0x08000 +#define JZ_NAND_MEM_ADDR_OFFSET 0x10000 struct jz_nand { struct mtd_info mtd; @@ -62,8 +63,11 @@ struct jz_nand { void __iomem *base; struct resource *mem; - void __iomem *bank_base; - struct resource *bank_mem; + unsigned char banks[JZ_NAND_NUM_BANKS]; + void __iomem *bank_base[JZ_NAND_NUM_BANKS]; + struct resource *bank_mem[JZ_NAND_NUM_BANKS]; + + int selected_bank; struct jz_nand_platform_data *pdata; bool is_reading; @@ -74,26 +78,50 @@ static inline struct jz_nand *mtd_to_jz_ return container_of(mtd, struct jz_nand, mtd); } +static void jz_nand_select_chip(struct mtd_info *mtd, int chipnr) +{ + struct jz_nand *nand = mtd_to_jz_nand(mtd); + struct nand_chip *chip = mtd->priv; + uint32_t ctrl; + int banknr; + + ctrl = readl(nand->base + JZ_REG_NAND_CTRL); + ctrl &= ~JZ_NAND_CTRL_ASSERT_CHIP_MASK; + + if (chipnr == -1) { + banknr = -1; + } else { + banknr = nand->banks[chipnr] - 1; + chip->IO_ADDR_R = nand->bank_base[banknr]; + chip->IO_ADDR_W = nand->bank_base[banknr]; + } + writel(ctrl, nand->base + JZ_REG_NAND_CTRL); + + nand->selected_bank = banknr; +} + static void jz_nand_cmd_ctrl(struct mtd_info *mtd, int dat, unsigned int ctrl) { struct jz_nand *nand = mtd_to_jz_nand(mtd); struct nand_chip *chip = mtd->priv; uint32_t reg; + void __iomem *bank_base = nand->bank_base[nand->selected_bank]; + + BUG_ON(nand->selected_bank < 0); if (ctrl & NAND_CTRL_CHANGE) { BUG_ON((ctrl & NAND_ALE) && (ctrl & NAND_CLE)); if (ctrl & NAND_ALE) - chip->IO_ADDR_W = nand->bank_base + JZ_NAND_MEM_ADDR_OFFSET; + bank_base += JZ_NAND_MEM_ADDR_OFFSET; else if (ctrl & NAND_CLE) - chip->IO_ADDR_W = nand->bank_base + JZ_NAND_MEM_CMD_OFFSET; - else - chip->IO_ADDR_W = nand->bank_base; + bank_base += JZ_NAND_MEM_CMD_OFFSET; + chip->IO_ADDR_W = bank_base; reg = readl(nand->base + JZ_REG_NAND_CTRL); if (ctrl & NAND_NCE) - reg |= JZ_NAND_CTRL_ASSERT_CHIP(0); + reg |= JZ_NAND_CTRL_ASSERT_CHIP(nand->selected_bank); else - reg &= ~JZ_NAND_CTRL_ASSERT_CHIP(0); + reg &= ~JZ_NAND_CTRL_ASSERT_CHIP(nand->selected_bank); writel(reg, nand->base + JZ_REG_NAND_CTRL); } if (dat != NAND_CMD_NONE) @@ -252,7 +280,7 @@ static int jz_nand_correct_ecc_rs(struct } static int jz_nand_ioremap_resource(struct platform_device *pdev, - const char *name, struct resource **res, void __iomem **base) + const char *name, struct resource **res, void *__iomem *base) { int ret; @@ -288,6 +316,90 @@ err: return ret; } +static inline void jz_nand_iounmap_resource(struct resource *res, void __iomem *base) +{ + iounmap(base); + release_mem_region(res->start, resource_size(res)); +} + +static int __devinit jz_nand_detect_bank(struct platform_device *pdev, struct jz_nand *nand, unsigned char bank, size_t chipnr, uint8_t *nand_maf_id, uint8_t *nand_dev_id) { + int ret; + int gpio; + char gpio_name[9]; + char res_name[6]; + uint32_t ctrl; + struct mtd_info *mtd = &nand->mtd; + struct nand_chip *chip = &nand->chip; + + /* Request GPIO port. */ + gpio = JZ_GPIO_MEM_CS0 + bank - 1; + sprintf(gpio_name, "NAND CS%d", bank); + ret = gpio_request(gpio, gpio_name); + if (ret) { + dev_warn(&pdev->dev, + "Failed to request %s gpio %d: %d\n", + gpio_name, gpio, ret); + goto notfound_gpio; + } + + /* Request I/O resource. */ + sprintf(res_name, "bank%d", bank); + ret = jz_nand_ioremap_resource(pdev, res_name, + &nand->bank_mem[bank - 1], + &nand->bank_base[bank - 1]); + if (ret) + goto notfound_resource; + + /* Enable chip in bank. */ + jz_gpio_set_function(gpio, JZ_GPIO_FUNC_MEM_CS0); + ctrl = readl(nand->base + JZ_REG_NAND_CTRL); + ctrl |= JZ_NAND_CTRL_ENABLE_CHIP(bank - 1); + writel(ctrl, nand->base + JZ_REG_NAND_CTRL); + + if (chipnr == 0) { + /* Detect first chip. */ + ret = nand_scan_ident(mtd, 1, NULL); + if (ret) + goto notfound_id; + + /* Retrieve the IDs from the first chip. */ + chip->select_chip(mtd, 0); + chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1); + chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1); + *nand_maf_id = chip->read_byte(mtd); + *nand_dev_id = chip->read_byte(mtd); + } else { + /* Detect additional chip. */ + chip->select_chip(mtd, chipnr); + chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1); + chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1); + if (*nand_maf_id != chip->read_byte(mtd) + || *nand_dev_id != chip->read_byte(mtd)) { + ret = -ENODEV; + goto notfound_id; + } + + /* Update size of the MTD. */ + chip->numchips++; + mtd->size += chip->chipsize; + } + + dev_info(&pdev->dev, "Found chip %i on bank %i\n", chipnr, bank); + return 0; + +notfound_id: + dev_info(&pdev->dev, "No chip found on bank %i\n", bank); + ctrl &= ~(JZ_NAND_CTRL_ENABLE_CHIP(bank - 1)); + writel(ctrl, nand->base + JZ_REG_NAND_CTRL); + jz_gpio_set_function(gpio, JZ_GPIO_FUNC_NONE); + jz_nand_iounmap_resource(nand->bank_mem[bank - 1], + nand->bank_base[bank - 1]); +notfound_resource: + gpio_free(gpio); +notfound_gpio: + return ret; +} + static int __devinit jz_nand_probe(struct platform_device *pdev) { int ret; @@ -295,6 +407,8 @@ static int __devinit jz_nand_probe(struc struct nand_chip *chip; struct mtd_info *mtd; struct jz_nand_platform_data *pdata = pdev->dev.platform_data; + size_t chipnr, bank_idx; + uint8_t nand_maf_id = 0, nand_dev_id = 0; nand = kzalloc(sizeof(*nand), GFP_KERNEL); if (!nand) { @@ -305,10 +419,6 @@ static int __devinit jz_nand_probe(struc ret = jz_nand_ioremap_resource(pdev, "mmio", &nand->mem, &nand->base); if (ret) goto err_free; - ret = jz_nand_ioremap_resource(pdev, "bank", &nand->bank_mem, - &nand->bank_base); - if (ret) - goto err_iounmap_mmio; if (pdata && gpio_is_valid(pdata->busy_gpio)) { ret = gpio_request(pdata->busy_gpio, "NAND busy pin"); @@ -316,7 +426,7 @@ static int __devinit jz_nand_probe(struc dev_err(&pdev->dev, "Failed to request busy gpio %d: %d\n", pdata->busy_gpio, ret); - goto err_iounmap_mem; + goto err_iounmap_mmio; } } @@ -338,22 +448,51 @@ static int __devinit jz_nand_probe(struc chip->chip_delay = 50; chip->cmd_ctrl = jz_nand_cmd_ctrl; + chip->select_chip = jz_nand_select_chip; if (pdata && gpio_is_valid(pdata->busy_gpio)) chip->dev_ready = jz_nand_dev_ready; - chip->IO_ADDR_R = nand->bank_base; - chip->IO_ADDR_W = nand->bank_base; - nand->pdata = pdata; platform_set_drvdata(pdev, nand); - writel(JZ_NAND_CTRL_ENABLE_CHIP(0), nand->base + JZ_REG_NAND_CTRL); - - ret = nand_scan_ident(mtd, 1, NULL); - if (ret) { - dev_err(&pdev->dev, "Failed to scan nand\n"); - goto err_gpio_free; + /* We are going to autodetect NAND chips in the banks specified in the + * platform data. Although nand_scan_ident() can detect multiple chips, + * it requires those chips to be numbered consecuitively, which is not + * always the case for external memory banks. And a fixed chip-to-bank + * mapping is not practical either, since for example Dingoo units + * produced at different times have NAND chips in different banks. + */ + chipnr = 0; + for (bank_idx = 0; bank_idx < JZ_NAND_NUM_BANKS; bank_idx++) { + unsigned char bank; + + /* If there is no platform data, look for NAND in bank 1, + * which is the most likely bank since it is the only one + * that can be booted from. + */ + bank = pdata ? pdata->banks[bank_idx] : bank_idx ^ 1; + if (bank == 0) + break; + if (bank > JZ_NAND_NUM_BANKS) { + dev_warn(&pdev->dev, + "Skipping non-existing bank: %d\n", bank); + continue; + } + /* The detection routine will directly or indirectly call + * jz_nand_select_chip(), so nand->banks has to contain the + * bank we're checking. + */ + nand->banks[chipnr] = bank; + if (jz_nand_detect_bank(pdev, nand, bank, chipnr, + &nand_maf_id, &nand_dev_id) == 0) + chipnr++; + else + nand->banks[chipnr] = 0; + } + if (chipnr == 0) { + dev_err(&pdev->dev, "No NAND chips found\n"); + goto err_gpio_busy; } if (pdata && pdata->ident_callback) { @@ -363,8 +502,8 @@ static int __devinit jz_nand_probe(struc ret = nand_scan_tail(mtd); if (ret) { - dev_err(&pdev->dev, "Failed to scan nand\n"); - goto err_gpio_free; + dev_err(&pdev->dev, "Failed to scan NAND\n"); + goto err_unclaim_banks; } ret = mtd_device_parse_register(mtd, NULL, 0, @@ -381,14 +520,21 @@ static int __devinit jz_nand_probe(struc return 0; err_nand_release: - nand_release(&nand->mtd); -err_gpio_free: + nand_release(mtd); +err_unclaim_banks: + while (chipnr--) { + unsigned char bank = nand->banks[chipnr]; + gpio_free(JZ_GPIO_MEM_CS0 + bank - 1); + jz_nand_iounmap_resource(nand->bank_mem[bank - 1], + nand->bank_base[bank - 1]); + } + writel(0, nand->base + JZ_REG_NAND_CTRL); +err_gpio_busy: + if (pdata && gpio_is_valid(pdata->busy_gpio)) + gpio_free(pdata->busy_gpio); platform_set_drvdata(pdev, NULL); - gpio_free(pdata->busy_gpio); -err_iounmap_mem: - iounmap(nand->bank_base); err_iounmap_mmio: - iounmap(nand->base); + jz_nand_iounmap_resource(nand->mem, nand->base); err_free: kfree(nand); return ret; @@ -397,16 +543,26 @@ err_free: static int __devexit jz_nand_remove(struct platform_device *pdev) { struct jz_nand *nand = platform_get_drvdata(pdev); + struct jz_nand_platform_data *pdata = pdev->dev.platform_data; + size_t i; nand_release(&nand->mtd); /* Deassert and disable all chips */ writel(0, nand->base + JZ_REG_NAND_CTRL); - iounmap(nand->bank_base); - release_mem_region(nand->bank_mem->start, resource_size(nand->bank_mem)); - iounmap(nand->base); - release_mem_region(nand->mem->start, resource_size(nand->mem)); + for (i = 0; i < JZ_NAND_NUM_BANKS; ++i) { + unsigned char bank = nand->banks[i]; + if (bank != 0) { + jz_nand_iounmap_resource(nand->bank_mem[bank - 1], + nand->bank_base[bank - 1]); + gpio_free(JZ_GPIO_MEM_CS0 + bank - 1); + } + } + if (pdata && gpio_is_valid(pdata->busy_gpio)) + gpio_free(pdata->busy_gpio); + + jz_nand_iounmap_resource(nand->mem, nand->base); platform_set_drvdata(pdev, NULL); kfree(nand);