/* * ASPEED Static Memory Controller driver * * Copyright (c) 2015-2016, IBM Corporation. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include #include #include #include #include #include #include #include #include #include #include #define DEVICE_NAME "aspeed-smc" /* * The driver only support SPI flash */ enum aspeed_smc_flash_type { smc_type_nor = 0, smc_type_nand = 1, smc_type_spi = 2, }; struct aspeed_smc_chip; struct aspeed_smc_info { u32 maxsize; /* maximum size of chip window */ u8 nce; /* number of chip enables */ bool hastype; /* flash type field exists in config reg */ u8 we0; /* shift for write enable bit for CE0 */ u8 ctl0; /* offset in regs of ctl for CE0 */ void (*set_4b)(struct aspeed_smc_chip *chip); }; static void aspeed_smc_chip_set_4b_spi_2400(struct aspeed_smc_chip *chip); static void aspeed_smc_chip_set_4b(struct aspeed_smc_chip *chip); static const struct aspeed_smc_info fmc_2400_info = { .maxsize = 64 * 1024 * 1024, .nce = 5, .hastype = true, .we0 = 16, .ctl0 = 0x10, .set_4b = aspeed_smc_chip_set_4b, }; static const struct aspeed_smc_info spi_2400_info = { .maxsize = 64 * 1024 * 1024, .nce = 1, .hastype = false, .we0 = 0, .ctl0 = 0x04, .set_4b = aspeed_smc_chip_set_4b_spi_2400, }; static const struct aspeed_smc_info fmc_2500_info = { .maxsize = 256 * 1024 * 1024, .nce = 3, .hastype = true, .we0 = 16, .ctl0 = 0x10, .set_4b = aspeed_smc_chip_set_4b, }; static const struct aspeed_smc_info spi_2500_info = { .maxsize = 128 * 1024 * 1024, .nce = 2, .hastype = false, .we0 = 16, .ctl0 = 0x10, .set_4b = aspeed_smc_chip_set_4b, }; enum aspeed_smc_ctl_reg_value { smc_base, /* base value without mode for other commands */ smc_read, /* command reg for (maybe fast) reads */ smc_write, /* command reg for writes */ smc_max, }; struct aspeed_smc_controller; struct aspeed_smc_chip { int cs; struct aspeed_smc_controller *controller; void __iomem *ctl; /* control register */ void __iomem *ahb_base; /* base of chip window */ u32 ctl_val[smc_max]; /* control settings */ enum aspeed_smc_flash_type type; /* what type of flash */ struct spi_nor nor; }; struct aspeed_smc_controller { struct device *dev; struct mutex mutex; /* controller access mutex */ const struct aspeed_smc_info *info; /* type info of controller */ void __iomem *regs; /* controller registers */ void __iomem *ahb_base; /* per-chip windows resource */ struct aspeed_smc_chip *chips[0]; /* pointers to attached chips */ }; /* * SPI Flash Configuration Register (AST2500 SPI) * or * Type setting Register (AST2500 FMC). * CE0 and CE1 can only be of type SPI. CE2 can be of type NOR but the * driver does not support it. */ #define CONFIG_REG 0x0 #define CONFIG_DISABLE_LEGACY BIT(31) /* 1 */ #define CONFIG_CE2_WRITE BIT(18) #define CONFIG_CE1_WRITE BIT(17) #define CONFIG_CE0_WRITE BIT(16) #define CONFIG_CE2_TYPE BIT(4) /* AST2500 FMC only */ #define CONFIG_CE1_TYPE BIT(2) /* AST2500 FMC only */ #define CONFIG_CE0_TYPE BIT(0) /* AST2500 FMC only */ /* * CE Control Register */ #define CE_CONTROL_REG 0x4 /* * CEx Control Register */ #define CONTROL_AAF_MODE BIT(31) #define CONTROL_IO_MODE_MASK GENMASK(30, 28) #define CONTROL_IO_DUAL_DATA BIT(29) #define CONTROL_IO_DUAL_ADDR_DATA (BIT(29) | BIT(28)) #define CONTROL_IO_QUAD_DATA BIT(30) #define CONTROL_IO_QUAD_ADDR_DATA (BIT(30) | BIT(28)) #define CONTROL_CE_INACTIVE_SHIFT 24 #define CONTROL_CE_INACTIVE_MASK GENMASK(27, \ CONTROL_CE_INACTIVE_SHIFT) /* 0 = 16T ... 15 = 1T T=HCLK */ #define CONTROL_COMMAND_SHIFT 16 #define CONTROL_DUMMY_COMMAND_OUT BIT(15) #define CONTROL_IO_DUMMY_HI BIT(14) #define CONTROL_IO_DUMMY_HI_SHIFT 14 #define CONTROL_CLK_DIV4 BIT(13) /* others */ #define CONTROL_IO_ADDRESS_4B BIT(13) /* AST2400 SPI */ #define CONTROL_RW_MERGE BIT(12) #define CONTROL_IO_DUMMY_LO_SHIFT 6 #define CONTROL_IO_DUMMY_LO GENMASK(7, \ CONTROL_IO_DUMMY_LO_SHIFT) #define CONTROL_IO_DUMMY_MASK (CONTROL_IO_DUMMY_HI | \ CONTROL_IO_DUMMY_LO) #define CONTROL_IO_DUMMY_SET(dummy) \ (((((dummy) >> 2) & 0x1) << CONTROL_IO_DUMMY_HI_SHIFT) | \ (((dummy) & 0x3) << CONTROL_IO_DUMMY_LO_SHIFT)) #define CONTROL_CLOCK_FREQ_SEL_SHIFT 8 #define CONTROL_CLOCK_FREQ_SEL_MASK GENMASK(11, \ CONTROL_CLOCK_FREQ_SEL_SHIFT) #define CONTROL_LSB_FIRST BIT(5) #define CONTROL_CLOCK_MODE_3 BIT(4) #define CONTROL_IN_DUAL_DATA BIT(3) #define CONTROL_CE_STOP_ACTIVE_CONTROL BIT(2) #define CONTROL_COMMAND_MODE_MASK GENMASK(1, 0) #define CONTROL_COMMAND_MODE_NORMAL 0 #define CONTROL_COMMAND_MODE_FREAD 1 #define CONTROL_COMMAND_MODE_WRITE 2 #define CONTROL_COMMAND_MODE_USER 3 #define CONTROL_KEEP_MASK \ (CONTROL_AAF_MODE | CONTROL_CE_INACTIVE_MASK | CONTROL_CLK_DIV4 | \ CONTROL_CLOCK_FREQ_SEL_MASK | CONTROL_LSB_FIRST | CONTROL_CLOCK_MODE_3) /* * The Segment Register uses a 8MB unit to encode the start address * and the end address of the mapping window of a flash SPI slave : * * | byte 1 | byte 2 | byte 3 | byte 4 | * +--------+--------+--------+--------+ * | end | start | 0 | 0 | */ #define SEGMENT_ADDR_REG0 0x30 #define SEGMENT_ADDR_START(_r) ((((_r) >> 16) & 0xFF) << 23) #define SEGMENT_ADDR_END(_r) ((((_r) >> 24) & 0xFF) << 23) /* * In user mode all data bytes read or written to the chip decode address * range are transferred to or from the SPI bus. The range is treated as a * fifo of arbitratry 1, 2, or 4 byte width but each write has to be aligned * to its size. The address within the multiple 8kB range is ignored when * sending bytes to the SPI bus. * * On the arm architecture, as of Linux version 4.3, memcpy_fromio and * memcpy_toio on little endian targets use the optimized memcpy routines * that were designed for well behavied memory storage. These routines * have a stutter if the source and destination are not both word aligned, * once with a duplicate access to the source after aligning to the * destination to a word boundary, and again with a duplicate access to * the source when the final byte count is not word aligned. * * When writing or reading the fifo this stutter discards data or sends * too much data to the fifo and can not be used by this driver. * * While the low level io string routines that implement the insl family do * the desired accesses and memory increments, the cross architecture io * macros make them essentially impossible to use on a memory mapped address * instead of a a token from the call to iomap of an io port. * * These fifo routines use readl and friends to a constant io port and update * the memory buffer pointer and count via explicit code. The final updates * to len are optimistically suppressed. */ static int aspeed_smc_read_from_ahb(void *buf, void __iomem *src, size_t len) { size_t offset = 0; if (IS_ALIGNED((uintptr_t)src, sizeof(uintptr_t)) && IS_ALIGNED((uintptr_t)buf, sizeof(uintptr_t))) { ioread32_rep(src, buf, len >> 2); offset = len & ~0x3; len -= offset; } ioread8_rep(src, (u8 *)buf + offset, len); return 0; } static int aspeed_smc_write_to_ahb(void __iomem *dst, const void *buf, size_t len) { size_t offset = 0; if (IS_ALIGNED((uintptr_t)dst, sizeof(uintptr_t)) && IS_ALIGNED((uintptr_t)buf, sizeof(uintptr_t))) { iowrite32_rep(dst, buf, len >> 2); offset = len & ~0x3; len -= offset; } iowrite8_rep(dst, (const u8 *)buf + offset, len); return 0; } static inline u32 aspeed_smc_chip_write_bit(struct aspeed_smc_chip *chip) { return BIT(chip->controller->info->we0 + chip->cs); } static void aspeed_smc_chip_check_config(struct aspeed_smc_chip *chip) { struct aspeed_smc_controller *controller = chip->controller; u32 reg; reg = readl(controller->regs + CONFIG_REG); if (reg & aspeed_smc_chip_write_bit(chip)) return; dev_dbg(controller->dev, "config write is not set ! @%p: 0x%08x\n", controller->regs + CONFIG_REG, reg); reg |= aspeed_smc_chip_write_bit(chip); writel(reg, controller->regs + CONFIG_REG); } static void aspeed_smc_start_user(struct spi_nor *nor) { struct aspeed_smc_chip *chip = nor->priv; u32 ctl = chip->ctl_val[smc_base]; /* * When the chip is controlled in user mode, we need write * access to send the opcodes to it. So check the config. */ aspeed_smc_chip_check_config(chip); ctl |= CONTROL_COMMAND_MODE_USER | CONTROL_CE_STOP_ACTIVE_CONTROL; writel(ctl, chip->ctl); ctl &= ~CONTROL_CE_STOP_ACTIVE_CONTROL; writel(ctl, chip->ctl); } static void aspeed_smc_stop_user(struct spi_nor *nor) { struct aspeed_smc_chip *chip = nor->priv; u32 ctl = chip->ctl_val[smc_read]; u32 ctl2 = ctl | CONTROL_COMMAND_MODE_USER | CONTROL_CE_STOP_ACTIVE_CONTROL; writel(ctl2, chip->ctl); /* stop user CE control */ writel(ctl, chip->ctl); /* default to fread or read mode */ } static int aspeed_smc_prep(struct spi_nor *nor, enum spi_nor_ops ops) { struct aspeed_smc_chip *chip = nor->priv; mutex_lock(&chip->controller->mutex); return 0; } static void aspeed_smc_unprep(struct spi_nor *nor, enum spi_nor_ops ops) { struct aspeed_smc_chip *chip = nor->priv; mutex_unlock(&chip->controller->mutex); } static int aspeed_smc_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len) { struct aspeed_smc_chip *chip = nor->priv; aspeed_smc_start_user(nor); aspeed_smc_write_to_ahb(chip->ahb_base, &opcode, 1); aspeed_smc_read_from_ahb(buf, chip->ahb_base, len); aspeed_smc_stop_user(nor); return 0; } static int aspeed_smc_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len) { struct aspeed_smc_chip *chip = nor->priv; aspeed_smc_start_user(nor); aspeed_smc_write_to_ahb(chip->ahb_base, &opcode, 1); aspeed_smc_write_to_ahb(chip->ahb_base, buf, len); aspeed_smc_stop_user(nor); return 0; } static void aspeed_smc_send_cmd_addr(struct spi_nor *nor, u8 cmd, u32 addr) { struct aspeed_smc_chip *chip = nor->priv; __be32 temp; u32 cmdaddr; switch (nor->addr_width) { default: WARN_ONCE(1, "Unexpected address width %u, defaulting to 3\n", nor->addr_width); /* FALLTHROUGH */ case 3: cmdaddr = addr & 0xFFFFFF; cmdaddr |= cmd << 24; temp = cpu_to_be32(cmdaddr); aspeed_smc_write_to_ahb(chip->ahb_base, &temp, 4); break; case 4: temp = cpu_to_be32(addr); aspeed_smc_write_to_ahb(chip->ahb_base, &cmd, 1); aspeed_smc_write_to_ahb(chip->ahb_base, &temp, 4); break; } } static ssize_t aspeed_smc_read_user(struct spi_nor *nor, loff_t from, size_t len, u_char *read_buf) { struct aspeed_smc_chip *chip = nor->priv; int i; u8 dummy = 0xFF; aspeed_smc_start_user(nor); aspeed_smc_send_cmd_addr(nor, nor->read_opcode, from); for (i = 0; i < chip->nor.read_dummy / 8; i++) aspeed_smc_write_to_ahb(chip->ahb_base, &dummy, sizeof(dummy)); aspeed_smc_read_from_ahb(read_buf, chip->ahb_base, len); aspeed_smc_stop_user(nor); return len; } static ssize_t aspeed_smc_write_user(struct spi_nor *nor, loff_t to, size_t len, const u_char *write_buf) { struct aspeed_smc_chip *chip = nor->priv; aspeed_smc_start_user(nor); aspeed_smc_send_cmd_addr(nor, nor->program_opcode, to); aspeed_smc_write_to_ahb(chip->ahb_base, write_buf, len); aspeed_smc_stop_user(nor); return len; } static int aspeed_smc_unregister(struct aspeed_smc_controller *controller) { struct aspeed_smc_chip *chip; int n; for (n = 0; n < controller->info->nce; n++) { chip = controller->chips[n]; if (chip) mtd_device_unregister(&chip->nor.mtd); } return 0; } static int aspeed_smc_remove(struct platform_device *dev) { return aspeed_smc_unregister(platform_get_drvdata(dev)); } static const struct of_device_id aspeed_smc_matches[] = { { .compatible = "aspeed,ast2400-fmc", .data = &fmc_2400_info }, { .compatible = "aspeed,ast2400-spi", .data = &spi_2400_info }, { .compatible = "aspeed,ast2500-fmc", .data = &fmc_2500_info }, { .compatible = "aspeed,ast2500-spi", .data = &spi_2500_info }, { } }; MODULE_DEVICE_TABLE(of, aspeed_smc_matches); /* * Each chip has a mapping window defined by a segment address * register defining a start and an end address on the AHB bus. These * addresses can be configured to fit the chip size and offer a * contiguous memory region across chips. For the moment, we only * check that each chip segment is valid. */ static void __iomem *aspeed_smc_chip_base(struct aspeed_smc_chip *chip, struct resource *res) { struct aspeed_smc_controller *controller = chip->controller; u32 offset = 0; u32 reg; if (controller->info->nce > 1) { reg = readl(controller->regs + SEGMENT_ADDR_REG0 + chip->cs * 4); if (SEGMENT_ADDR_START(reg) >= SEGMENT_ADDR_END(reg)) return NULL; offset = SEGMENT_ADDR_START(reg) - res->start; } return controller->ahb_base + offset; } static void aspeed_smc_chip_enable_write(struct aspeed_smc_chip *chip) { struct aspeed_smc_controller *controller = chip->controller; u32 reg; reg = readl(controller->regs + CONFIG_REG); reg |= aspeed_smc_chip_write_bit(chip); writel(reg, controller->regs + CONFIG_REG); } static void aspeed_smc_chip_set_type(struct aspeed_smc_chip *chip, int type) { struct aspeed_smc_controller *controller = chip->controller; u32 reg; chip->type = type; reg = readl(controller->regs + CONFIG_REG); reg &= ~(3 << (chip->cs * 2)); reg |= chip->type << (chip->cs * 2); writel(reg, controller->regs + CONFIG_REG); } /* * The AST2500 FMC flash controller should be strapped by hardware, or * autodetected, but the AST2500 SPI flash needs to be set. */ static void aspeed_smc_chip_set_4b(struct aspeed_smc_chip *chip) { struct aspeed_smc_controller *controller = chip->controller; u32 reg; if (chip->controller->info == &spi_2500_info) { reg = readl(controller->regs + CE_CONTROL_REG); reg |= 1 << chip->cs; writel(reg, controller->regs + CE_CONTROL_REG); } } /* * The AST2400 SPI flash controller does not have a CE Control * register. It uses the CE0 control register to set 4Byte mode at the * controller level. */ static void aspeed_smc_chip_set_4b_spi_2400(struct aspeed_smc_chip *chip) { chip->ctl_val[smc_base] |= CONTROL_IO_ADDRESS_4B; chip->ctl_val[smc_read] |= CONTROL_IO_ADDRESS_4B; } static int aspeed_smc_chip_setup_init(struct aspeed_smc_chip *chip, struct resource *res) { struct aspeed_smc_controller *controller = chip->controller; const struct aspeed_smc_info *info = controller->info; u32 reg, base_reg; /* * Always turn on the write enable bit to allow opcodes to be * sent in user mode. */ aspeed_smc_chip_enable_write(chip); /* The driver only supports SPI type flash */ if (info->hastype) aspeed_smc_chip_set_type(chip, smc_type_spi); /* * Configure chip base address in memory */ chip->ahb_base = aspeed_smc_chip_base(chip, res); if (!chip->ahb_base) { dev_warn(chip->nor.dev, "CE segment window closed.\n"); return -EINVAL; } /* * Get value of the inherited control register. U-Boot usually * does some timing calibration on the FMC chip, so it's good * to keep them. In the future, we should handle calibration * from Linux. */ reg = readl(chip->ctl); dev_dbg(controller->dev, "control register: %08x\n", reg); base_reg = reg & CONTROL_KEEP_MASK; if (base_reg != reg) { dev_dbg(controller->dev, "control register changed to: %08x\n", base_reg); } chip->ctl_val[smc_base] = base_reg; /* * Retain the prior value of the control register as the * default if it was normal access mode. Otherwise start with * the sanitized base value set to read mode. */ if ((reg & CONTROL_COMMAND_MODE_MASK) == CONTROL_COMMAND_MODE_NORMAL) chip->ctl_val[smc_read] = reg; else chip->ctl_val[smc_read] = chip->ctl_val[smc_base] | CONTROL_COMMAND_MODE_NORMAL; dev_dbg(controller->dev, "default control register: %08x\n", chip->ctl_val[smc_read]); return 0; } static int aspeed_smc_chip_setup_finish(struct aspeed_smc_chip *chip) { struct aspeed_smc_controller *controller = chip->controller; const struct aspeed_smc_info *info = controller->info; u32 cmd; if (chip->nor.addr_width == 4 && info->set_4b) info->set_4b(chip); /* * base mode has not been optimized yet. use it for writes. */ chip->ctl_val[smc_write] = chip->ctl_val[smc_base] | chip->nor.program_opcode << CONTROL_COMMAND_SHIFT | CONTROL_COMMAND_MODE_WRITE; dev_dbg(controller->dev, "write control register: %08x\n", chip->ctl_val[smc_write]); /* * TODO: Adjust clocks if fast read is supported and interpret * SPI-NOR flags to adjust controller settings. */ if (chip->nor.read_proto == SNOR_PROTO_1_1_1) { if (chip->nor.read_dummy == 0) cmd = CONTROL_COMMAND_MODE_NORMAL; else cmd = CONTROL_COMMAND_MODE_FREAD; } else { dev_err(chip->nor.dev, "unsupported SPI read mode\n"); return -EINVAL; } chip->ctl_val[smc_read] |= cmd | CONTROL_IO_DUMMY_SET(chip->nor.read_dummy / 8); dev_dbg(controller->dev, "base control register: %08x\n", chip->ctl_val[smc_read]); return 0; } static int aspeed_smc_setup_flash(struct aspeed_smc_controller *controller, struct device_node *np, struct resource *r) { const struct spi_nor_hwcaps hwcaps = { .mask = SNOR_HWCAPS_READ | SNOR_HWCAPS_READ_FAST | SNOR_HWCAPS_PP, }; const struct aspeed_smc_info *info = controller->info; struct device *dev = controller->dev; struct device_node *child; unsigned int cs; int ret = -ENODEV; for_each_available_child_of_node(np, child) { struct aspeed_smc_chip *chip; struct spi_nor *nor; struct mtd_info *mtd; /* This driver does not support NAND or NOR flash devices. */ if (!of_device_is_compatible(child, "jedec,spi-nor")) continue; ret = of_property_read_u32(child, "reg", &cs); if (ret) { dev_err(dev, "Couldn't not read chip select.\n"); break; } if (cs >= info->nce) { dev_err(dev, "Chip select %d out of range.\n", cs); ret = -ERANGE; break; } if (controller->chips[cs]) { dev_err(dev, "Chip select %d already in use by %s\n", cs, dev_name(controller->chips[cs]->nor.dev)); ret = -EBUSY; break; } chip = devm_kzalloc(controller->dev, sizeof(*chip), GFP_KERNEL); if (!chip) { ret = -ENOMEM; break; } chip->controller = controller; chip->ctl = controller->regs + info->ctl0 + cs * 4; chip->cs = cs; nor = &chip->nor; mtd = &nor->mtd; nor->dev = dev; nor->priv = chip; spi_nor_set_flash_node(nor, child); nor->read = aspeed_smc_read_user; nor->write = aspeed_smc_write_user; nor->read_reg = aspeed_smc_read_reg; nor->write_reg = aspeed_smc_write_reg; nor->prepare = aspeed_smc_prep; nor->unprepare = aspeed_smc_unprep; ret = aspeed_smc_chip_setup_init(chip, r); if (ret) break; /* * TODO: Add support for Dual and Quad SPI protocols * attach when board support is present as determined * by of property. */ ret = spi_nor_scan(nor, NULL, &hwcaps); if (ret) break; ret = aspeed_smc_chip_setup_finish(chip); if (ret) break; ret = mtd_device_register(mtd, NULL, 0); if (ret) break; controller->chips[cs] = chip; } if (ret) aspeed_smc_unregister(controller); return ret; } static int aspeed_smc_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; struct device *dev = &pdev->dev; struct aspeed_smc_controller *controller; const struct of_device_id *match; const struct aspeed_smc_info *info; struct resource *res; int ret; match = of_match_device(aspeed_smc_matches, &pdev->dev); if (!match || !match->data) return -ENODEV; info = match->data; controller = devm_kzalloc(&pdev->dev, sizeof(*controller) + info->nce * sizeof(controller->chips[0]), GFP_KERNEL); if (!controller) return -ENOMEM; controller->info = info; controller->dev = dev; mutex_init(&controller->mutex); platform_set_drvdata(pdev, controller); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); controller->regs = devm_ioremap_resource(dev, res); if (IS_ERR(controller->regs)) return PTR_ERR(controller->regs); res = platform_get_resource(pdev, IORESOURCE_MEM, 1); controller->ahb_base = devm_ioremap_resource(dev, res); if (IS_ERR(controller->ahb_base)) return PTR_ERR(controller->ahb_base); ret = aspeed_smc_setup_flash(controller, np, res); if (ret) dev_err(dev, "Aspeed SMC probe failed %d\n", ret); return ret; } static struct platform_driver aspeed_smc_driver = { .probe = aspeed_smc_probe, .remove = aspeed_smc_remove, .driver = { .name = DEVICE_NAME, .of_match_table = aspeed_smc_matches, } }; module_platform_driver(aspeed_smc_driver); MODULE_DESCRIPTION("ASPEED Static Memory Controller Driver"); MODULE_AUTHOR("Cedric Le Goater "); MODULE_LICENSE("GPL v2");