diff options
Diffstat (limited to 'drivers/spi/spi-aspeed-smc.c')
| -rw-r--r-- | drivers/spi/spi-aspeed-smc.c | 1210 |
1 files changed, 1210 insertions, 0 deletions
diff --git a/drivers/spi/spi-aspeed-smc.c b/drivers/spi/spi-aspeed-smc.c new file mode 100644 index 000000000000..496f3e1e9079 --- /dev/null +++ b/drivers/spi/spi-aspeed-smc.c @@ -0,0 +1,1210 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * ASPEED FMC/SPI Memory Controller Driver + * + * Copyright (c) 2015-2022, IBM Corporation. + * Copyright (c) 2020, ASPEED Corporation. + */ + +#include <linux/clk.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi-mem.h> + +#define DEVICE_NAME "spi-aspeed-smc" + +/* Type setting Register */ +#define CONFIG_REG 0x0 +#define CONFIG_TYPE_SPI 0x2 + +/* CE Control Register */ +#define CE_CTRL_REG 0x4 + +/* CEx Control Register */ +#define CE0_CTRL_REG 0x10 +#define CTRL_IO_MODE_MASK GENMASK(30, 28) +#define CTRL_IO_SINGLE_DATA 0x0 +#define CTRL_IO_DUAL_DATA BIT(29) +#define CTRL_IO_QUAD_DATA BIT(30) +#define CTRL_COMMAND_SHIFT 16 +#define CTRL_IO_ADDRESS_4B BIT(13) /* AST2400 SPI only */ +#define CTRL_IO_DUMMY_SET(dummy) \ + (((((dummy) >> 2) & 0x1) << 14) | (((dummy) & 0x3) << 6)) +#define CTRL_FREQ_SEL_SHIFT 8 +#define CTRL_FREQ_SEL_MASK GENMASK(11, CTRL_FREQ_SEL_SHIFT) +#define CTRL_CE_STOP_ACTIVE BIT(2) +#define CTRL_IO_MODE_CMD_MASK GENMASK(1, 0) +#define CTRL_IO_MODE_NORMAL 0x0 +#define CTRL_IO_MODE_READ 0x1 +#define CTRL_IO_MODE_WRITE 0x2 +#define CTRL_IO_MODE_USER 0x3 + +#define CTRL_IO_CMD_MASK 0xf0ff40c3 + +/* CEx Address Decoding Range Register */ +#define CE0_SEGMENT_ADDR_REG 0x30 + +/* CEx Read timing compensation register */ +#define CE0_TIMING_COMPENSATION_REG 0x94 + +enum aspeed_spi_ctl_reg_value { + ASPEED_SPI_BASE, + ASPEED_SPI_READ, + ASPEED_SPI_WRITE, + ASPEED_SPI_MAX, +}; + +struct aspeed_spi; + +struct aspeed_spi_chip { + struct aspeed_spi *aspi; + u32 cs; + void __iomem *ctl; + void __iomem *ahb_base; + u32 ahb_window_size; + u32 ctl_val[ASPEED_SPI_MAX]; + u32 clk_freq; +}; + +struct aspeed_spi_data { + u32 ctl0; + u32 max_cs; + bool hastype; + u32 mode_bits; + u32 we0; + u32 timing; + u32 hclk_mask; + u32 hdiv_max; + + u32 (*segment_start)(struct aspeed_spi *aspi, u32 reg); + u32 (*segment_end)(struct aspeed_spi *aspi, u32 reg); + u32 (*segment_reg)(struct aspeed_spi *aspi, u32 start, u32 end); + int (*calibrate)(struct aspeed_spi_chip *chip, u32 hdiv, + const u8 *golden_buf, u8 *test_buf); +}; + +#define ASPEED_SPI_MAX_NUM_CS 5 + +struct aspeed_spi { + const struct aspeed_spi_data *data; + + void __iomem *regs; + void __iomem *ahb_base; + u32 ahb_base_phy; + u32 ahb_window_size; + struct device *dev; + + struct clk *clk; + u32 clk_freq; + + struct aspeed_spi_chip chips[ASPEED_SPI_MAX_NUM_CS]; +}; + +static u32 aspeed_spi_get_io_mode(const struct spi_mem_op *op) +{ + switch (op->data.buswidth) { + case 1: + return CTRL_IO_SINGLE_DATA; + case 2: + return CTRL_IO_DUAL_DATA; + case 4: + return CTRL_IO_QUAD_DATA; + default: + return CTRL_IO_SINGLE_DATA; + } +} + +static void aspeed_spi_set_io_mode(struct aspeed_spi_chip *chip, u32 io_mode) +{ + u32 ctl; + + if (io_mode > 0) { + ctl = readl(chip->ctl) & ~CTRL_IO_MODE_MASK; + ctl |= io_mode; + writel(ctl, chip->ctl); + } +} + +static void aspeed_spi_start_user(struct aspeed_spi_chip *chip) +{ + u32 ctl = chip->ctl_val[ASPEED_SPI_BASE]; + + ctl |= CTRL_IO_MODE_USER | CTRL_CE_STOP_ACTIVE; + writel(ctl, chip->ctl); + + ctl &= ~CTRL_CE_STOP_ACTIVE; + writel(ctl, chip->ctl); +} + +static void aspeed_spi_stop_user(struct aspeed_spi_chip *chip) +{ + u32 ctl = chip->ctl_val[ASPEED_SPI_READ] | + CTRL_IO_MODE_USER | CTRL_CE_STOP_ACTIVE; + + writel(ctl, chip->ctl); + + /* Restore defaults */ + writel(chip->ctl_val[ASPEED_SPI_READ], chip->ctl); +} + +static int aspeed_spi_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_spi_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 int aspeed_spi_send_cmd_addr(struct aspeed_spi_chip *chip, u8 addr_nbytes, + u64 offset, u32 opcode) +{ + __be32 temp; + u32 cmdaddr; + + switch (addr_nbytes) { + case 3: + cmdaddr = offset & 0xFFFFFF; + cmdaddr |= opcode << 24; + + temp = cpu_to_be32(cmdaddr); + aspeed_spi_write_to_ahb(chip->ahb_base, &temp, 4); + break; + case 4: + temp = cpu_to_be32(offset); + aspeed_spi_write_to_ahb(chip->ahb_base, &opcode, 1); + aspeed_spi_write_to_ahb(chip->ahb_base, &temp, 4); + break; + default: + WARN_ONCE(1, "Unexpected address width %u", addr_nbytes); + return -EOPNOTSUPP; + } + return 0; +} + +static int aspeed_spi_read_reg(struct aspeed_spi_chip *chip, + const struct spi_mem_op *op) +{ + aspeed_spi_start_user(chip); + aspeed_spi_write_to_ahb(chip->ahb_base, &op->cmd.opcode, 1); + aspeed_spi_read_from_ahb(op->data.buf.in, + chip->ahb_base, op->data.nbytes); + aspeed_spi_stop_user(chip); + return 0; +} + +static int aspeed_spi_write_reg(struct aspeed_spi_chip *chip, + const struct spi_mem_op *op) +{ + aspeed_spi_start_user(chip); + aspeed_spi_write_to_ahb(chip->ahb_base, &op->cmd.opcode, 1); + aspeed_spi_write_to_ahb(chip->ahb_base, op->data.buf.out, + op->data.nbytes); + aspeed_spi_stop_user(chip); + return 0; +} + +static ssize_t aspeed_spi_read_user(struct aspeed_spi_chip *chip, + const struct spi_mem_op *op, + u64 offset, size_t len, void *buf) +{ + int io_mode = aspeed_spi_get_io_mode(op); + u8 dummy = 0xFF; + int i; + int ret; + + aspeed_spi_start_user(chip); + + ret = aspeed_spi_send_cmd_addr(chip, op->addr.nbytes, offset, op->cmd.opcode); + if (ret < 0) + return ret; + + if (op->dummy.buswidth && op->dummy.nbytes) { + for (i = 0; i < op->dummy.nbytes / op->dummy.buswidth; i++) + aspeed_spi_write_to_ahb(chip->ahb_base, &dummy, sizeof(dummy)); + } + + aspeed_spi_set_io_mode(chip, io_mode); + + aspeed_spi_read_from_ahb(buf, chip->ahb_base, len); + aspeed_spi_stop_user(chip); + return 0; +} + +static ssize_t aspeed_spi_write_user(struct aspeed_spi_chip *chip, + const struct spi_mem_op *op) +{ + int ret; + + aspeed_spi_start_user(chip); + ret = aspeed_spi_send_cmd_addr(chip, op->addr.nbytes, op->addr.val, op->cmd.opcode); + if (ret < 0) + return ret; + aspeed_spi_write_to_ahb(chip->ahb_base, op->data.buf.out, op->data.nbytes); + aspeed_spi_stop_user(chip); + return 0; +} + +/* support for 1-1-1, 1-1-2 or 1-1-4 */ +static bool aspeed_spi_supports_op(struct spi_mem *mem, const struct spi_mem_op *op) +{ + if (op->cmd.buswidth > 1) + return false; + + if (op->addr.nbytes != 0) { + if (op->addr.buswidth > 1) + return false; + if (op->addr.nbytes < 3 || op->addr.nbytes > 4) + return false; + } + + if (op->dummy.nbytes != 0) { + if (op->dummy.buswidth > 1 || op->dummy.nbytes > 7) + return false; + } + + if (op->data.nbytes != 0 && op->data.buswidth > 4) + return false; + + return spi_mem_default_supports_op(mem, op); +} + +static const struct aspeed_spi_data ast2400_spi_data; + +static int do_aspeed_spi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op) +{ + struct aspeed_spi *aspi = spi_controller_get_devdata(mem->spi->master); + struct aspeed_spi_chip *chip = &aspi->chips[mem->spi->chip_select]; + u32 addr_mode, addr_mode_backup; + u32 ctl_val; + int ret = 0; + + dev_dbg(aspi->dev, + "CE%d %s OP %#x mode:%d.%d.%d.%d naddr:%#x ndummies:%#x len:%#x", + chip->cs, op->data.dir == SPI_MEM_DATA_IN ? "read" : "write", + op->cmd.opcode, op->cmd.buswidth, op->addr.buswidth, + op->dummy.buswidth, op->data.buswidth, + op->addr.nbytes, op->dummy.nbytes, op->data.nbytes); + + addr_mode = readl(aspi->regs + CE_CTRL_REG); + addr_mode_backup = addr_mode; + + ctl_val = chip->ctl_val[ASPEED_SPI_BASE]; + ctl_val &= ~CTRL_IO_CMD_MASK; + + ctl_val |= op->cmd.opcode << CTRL_COMMAND_SHIFT; + + /* 4BYTE address mode */ + if (op->addr.nbytes) { + if (op->addr.nbytes == 4) + addr_mode |= (0x11 << chip->cs); + else + addr_mode &= ~(0x11 << chip->cs); + + if (op->addr.nbytes == 4 && chip->aspi->data == &ast2400_spi_data) + ctl_val |= CTRL_IO_ADDRESS_4B; + } + + if (op->dummy.nbytes) + ctl_val |= CTRL_IO_DUMMY_SET(op->dummy.nbytes / op->dummy.buswidth); + + if (op->data.nbytes) + ctl_val |= aspeed_spi_get_io_mode(op); + + if (op->data.dir == SPI_MEM_DATA_OUT) + ctl_val |= CTRL_IO_MODE_WRITE; + else + ctl_val |= CTRL_IO_MODE_READ; + + if (addr_mode != addr_mode_backup) + writel(addr_mode, aspi->regs + CE_CTRL_REG); + writel(ctl_val, chip->ctl); + + if (op->data.dir == SPI_MEM_DATA_IN) { + if (!op->addr.nbytes) + ret = aspeed_spi_read_reg(chip, op); + else + ret = aspeed_spi_read_user(chip, op, op->addr.val, + op->data.nbytes, op->data.buf.in); + } else { + if (!op->addr.nbytes) + ret = aspeed_spi_write_reg(chip, op); + else + ret = aspeed_spi_write_user(chip, op); + } + + /* Restore defaults */ + if (addr_mode != addr_mode_backup) + writel(addr_mode_backup, aspi->regs + CE_CTRL_REG); + writel(chip->ctl_val[ASPEED_SPI_READ], chip->ctl); + return ret; +} + +static int aspeed_spi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op) +{ + int ret; + + ret = do_aspeed_spi_exec_op(mem, op); + if (ret) + dev_err(&mem->spi->dev, "operation failed: %d\n", ret); + return ret; +} + +static const char *aspeed_spi_get_name(struct spi_mem *mem) +{ + struct aspeed_spi *aspi = spi_controller_get_devdata(mem->spi->master); + struct device *dev = aspi->dev; + + return devm_kasprintf(dev, GFP_KERNEL, "%s.%d", dev_name(dev), mem->spi->chip_select); +} + +struct aspeed_spi_window { + u32 cs; + u32 offset; + u32 size; +}; + +static void aspeed_spi_get_windows(struct aspeed_spi *aspi, + struct aspeed_spi_window windows[ASPEED_SPI_MAX_NUM_CS]) +{ + const struct aspeed_spi_data *data = aspi->data; + u32 reg_val; + u32 cs; + + for (cs = 0; cs < aspi->data->max_cs; cs++) { + reg_val = readl(aspi->regs + CE0_SEGMENT_ADDR_REG + cs * 4); + windows[cs].cs = cs; + windows[cs].size = data->segment_end(aspi, reg_val) - + data->segment_start(aspi, reg_val); + windows[cs].offset = cs ? windows[cs - 1].offset + windows[cs - 1].size : 0; + dev_vdbg(aspi->dev, "CE%d offset=0x%.8x size=0x%x\n", cs, + windows[cs].offset, windows[cs].size); + } +} + +/* + * On the AST2600, some CE windows are closed by default at reset but + * U-Boot should open all. + */ +static int aspeed_spi_chip_set_default_window(struct aspeed_spi_chip *chip) +{ + struct aspeed_spi *aspi = chip->aspi; + struct aspeed_spi_window windows[ASPEED_SPI_MAX_NUM_CS] = { 0 }; + struct aspeed_spi_window *win = &windows[chip->cs]; + + /* No segment registers for the AST2400 SPI controller */ + if (aspi->data == &ast2400_spi_data) { + win->offset = 0; + win->size = aspi->ahb_window_size; + } else { + aspeed_spi_get_windows(aspi, windows); + } + + chip->ahb_base = aspi->ahb_base + win->offset; + chip->ahb_window_size = win->size; + + dev_dbg(aspi->dev, "CE%d default window [ 0x%.8x - 0x%.8x ] %dMB", + chip->cs, aspi->ahb_base_phy + win->offset, + aspi->ahb_base_phy + win->offset + win->size - 1, + win->size >> 20); + + return chip->ahb_window_size ? 0 : -1; +} + +static int aspeed_spi_set_window(struct aspeed_spi *aspi, + const struct aspeed_spi_window *win) +{ + u32 start = aspi->ahb_base_phy + win->offset; + u32 end = start + win->size; + void __iomem *seg_reg = aspi->regs + CE0_SEGMENT_ADDR_REG + win->cs * 4; + u32 seg_val_backup = readl(seg_reg); + u32 seg_val = aspi->data->segment_reg(aspi, start, end); + + if (seg_val == seg_val_backup) + return 0; + + writel(seg_val, seg_reg); + + /* + * Restore initial value if something goes wrong else we could + * loose access to the chip. + */ + if (seg_val != readl(seg_reg)) { + dev_err(aspi->dev, "CE%d invalid window [ 0x%.8x - 0x%.8x ] %dMB", + win->cs, start, end - 1, win->size >> 20); + writel(seg_val_backup, seg_reg); + return -EIO; + } + + if (win->size) + dev_dbg(aspi->dev, "CE%d new window [ 0x%.8x - 0x%.8x ] %dMB", + win->cs, start, end - 1, win->size >> 20); + else + dev_dbg(aspi->dev, "CE%d window closed", win->cs); + + return 0; +} + +/* + * Yet to be done when possible : + * - Align mappings on flash size (we don't have the info) + * - ioremap each window, not strictly necessary since the overall window + * is correct. + */ +static const struct aspeed_spi_data ast2500_spi_data; +static const struct aspeed_spi_data ast2600_spi_data; +static const struct aspeed_spi_data ast2600_fmc_data; + +static int aspeed_spi_chip_adjust_window(struct aspeed_spi_chip *chip, + u32 local_offset, u32 size) +{ + struct aspeed_spi *aspi = chip->aspi; + struct aspeed_spi_window windows[ASPEED_SPI_MAX_NUM_CS] = { 0 }; + struct aspeed_spi_window *win = &windows[chip->cs]; + int ret; + + /* No segment registers for the AST2400 SPI controller */ + if (aspi->data == &ast2400_spi_data) + return 0; + + /* + * Due to an HW issue on the AST2500 SPI controller, the CE0 + * window size should be smaller than the maximum 128MB. + */ + if (aspi->data == &ast2500_spi_data && chip->cs == 0 && size == SZ_128M) { + size = 120 << 20; + dev_info(aspi->dev, "CE%d window resized to %dMB (AST2500 HW quirk)", + chip->cs, size >> 20); + } + + /* + * The decoding size of AST2600 SPI controller should set at + * least 2MB. + */ + if ((aspi->data == &ast2600_spi_data || aspi->data == &ast2600_fmc_data) && + size < SZ_2M) { + size = SZ_2M; + dev_info(aspi->dev, "CE%d window resized to %dMB (AST2600 Decoding)", + chip->cs, size >> 20); + } + + aspeed_spi_get_windows(aspi, windows); + + /* Adjust this chip window */ + win->offset += local_offset; + win->size = size; + + if (win->offset + win->size > aspi->ahb_window_size) { + win->size = aspi->ahb_window_size - win->offset; + dev_warn(aspi->dev, "CE%d window resized to %dMB", chip->cs, win->size >> 20); + } + + ret = aspeed_spi_set_window(aspi, win); + if (ret) + return ret; + + /* Update chip mapping info */ + chip->ahb_base = aspi->ahb_base + win->offset; + chip->ahb_window_size = win->size; + + /* + * Also adjust next chip window to make sure that it does not + * overlap with the current window. + */ + if (chip->cs < aspi->data->max_cs - 1) { + struct aspeed_spi_window *next = &windows[chip->cs + 1]; + + /* Change offset and size to keep the same end address */ + if ((next->offset + next->size) > (win->offset + win->size)) + next->size = (next->offset + next->size) - (win->offset + win->size); + else + next->size = 0; + next->offset = win->offset + win->size; + + aspeed_spi_set_window(aspi, next); + } + return 0; +} + +static int aspeed_spi_do_calibration(struct aspeed_spi_chip *chip); + +static int aspeed_spi_dirmap_create(struct spi_mem_dirmap_desc *desc) +{ + struct aspeed_spi *aspi = spi_controller_get_devdata(desc->mem->spi->master); + struct aspeed_spi_chip *chip = &aspi->chips[desc->mem->spi->chip_select]; + struct spi_mem_op *op = &desc->info.op_tmpl; + u32 ctl_val; + int ret = 0; + + chip->clk_freq = desc->mem->spi->max_speed_hz; + + /* Only for reads */ + if (op->data.dir != SPI_MEM_DATA_IN) + return -EOPNOTSUPP; + + aspeed_spi_chip_adjust_window(chip, desc->info.offset, desc->info.length); + + if (desc->info.length > chip->ahb_window_size) + dev_warn(aspi->dev, "CE%d window (%dMB) too small for mapping", + chip->cs, chip->ahb_window_size >> 20); + + /* Define the default IO read settings */ + ctl_val = readl(chip->ctl) & ~CTRL_IO_CMD_MASK; + ctl_val |= aspeed_spi_get_io_mode(op) | + op->cmd.opcode << CTRL_COMMAND_SHIFT | + CTRL_IO_DUMMY_SET(op->dummy.nbytes / op->dummy.buswidth) | + CTRL_IO_MODE_READ; + + /* Tune 4BYTE address mode */ + if (op->addr.nbytes) { + u32 addr_mode = readl(aspi->regs + CE_CTRL_REG); + + if (op->addr.nbytes == 4) + addr_mode |= (0x11 << chip->cs); + else + addr_mode &= ~(0x11 << chip->cs); + writel(addr_mode, aspi->regs + CE_CTRL_REG); + + /* AST2400 SPI controller sets 4BYTE address mode in + * CE0 Control Register + */ + if (op->addr.nbytes == 4 && chip->aspi->data == &ast2400_spi_data) + ctl_val |= CTRL_IO_ADDRESS_4B; + } + + /* READ mode is the controller default setting */ + chip->ctl_val[ASPEED_SPI_READ] = ctl_val; + writel(chip->ctl_val[ASPEED_SPI_READ], chip->ctl); + + ret = aspeed_spi_do_calibration(chip); + + dev_info(aspi->dev, "CE%d read buswidth:%d [0x%08x]\n", + chip->cs, op->data.buswidth, chip->ctl_val[ASPEED_SPI_READ]); + + return ret; +} + +static ssize_t aspeed_spi_dirmap_read(struct spi_mem_dirmap_desc *desc, + u64 offset, size_t len, void *buf) +{ + struct aspeed_spi *aspi = spi_controller_get_devdata(desc->mem->spi->master); + struct aspeed_spi_chip *chip = &aspi->chips[desc->mem->spi->chip_select]; + + /* Switch to USER command mode if mapping window is too small */ + if (chip->ahb_window_size < offset + len) { + int ret; + + ret = aspeed_spi_read_user(chip, &desc->info.op_tmpl, offset, len, buf); + if (ret < 0) + return ret; + } else { + memcpy_fromio(buf, chip->ahb_base + offset, len); + } + + return len; +} + +static const struct spi_controller_mem_ops aspeed_spi_mem_ops = { + .supports_op = aspeed_spi_supports_op, + .exec_op = aspeed_spi_exec_op, + .get_name = aspeed_spi_get_name, + .dirmap_create = aspeed_spi_dirmap_create, + .dirmap_read = aspeed_spi_dirmap_read, +}; + +static void aspeed_spi_chip_set_type(struct aspeed_spi *aspi, unsigned int cs, int type) +{ + u32 reg; + + reg = readl(aspi->regs + CONFIG_REG); + reg &= ~(0x3 << (cs * 2)); + reg |= type << (cs * 2); + writel(reg, aspi->regs + CONFIG_REG); +} + +static void aspeed_spi_chip_enable(struct aspeed_spi *aspi, unsigned int cs, bool enable) +{ + u32 we_bit = BIT(aspi->data->we0 + cs); + u32 reg = readl(aspi->regs + CONFIG_REG); + + if (enable) + reg |= we_bit; + else + reg &= ~we_bit; + writel(reg, aspi->regs + CONFIG_REG); +} + +static int aspeed_spi_setup(struct spi_device *spi) +{ + struct aspeed_spi *aspi = spi_controller_get_devdata(spi->master); + const struct aspeed_spi_data *data = aspi->data; + unsigned int cs = spi->chip_select; + struct aspeed_spi_chip *chip = &aspi->chips[cs]; + + chip->aspi = aspi; + chip->cs = cs; + chip->ctl = aspi->regs + data->ctl0 + cs * 4; + + /* The driver only supports SPI type flash */ + if (data->hastype) + aspeed_spi_chip_set_type(aspi, cs, CONFIG_TYPE_SPI); + + if (aspeed_spi_chip_set_default_window(chip) < 0) { + dev_warn(aspi->dev, "CE%d window invalid", cs); + return -EINVAL; + } + + aspeed_spi_chip_enable(aspi, cs, true); + + chip->ctl_val[ASPEED_SPI_BASE] = CTRL_CE_STOP_ACTIVE | CTRL_IO_MODE_USER; + + dev_dbg(aspi->dev, "CE%d setup done\n", cs); + return 0; +} + +static void aspeed_spi_cleanup(struct spi_device *spi) +{ + struct aspeed_spi *aspi = spi_controller_get_devdata(spi->master); + unsigned int cs = spi->chip_select; + + aspeed_spi_chip_enable(aspi, cs, false); + + dev_dbg(aspi->dev, "CE%d cleanup done\n", cs); +} + +static void aspeed_spi_enable(struct aspeed_spi *aspi, bool enable) +{ + int cs; + + for (cs = 0; cs < aspi->data->max_cs; cs++) + aspeed_spi_chip_enable(aspi, cs, enable); +} + +static int aspeed_spi_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + const struct aspeed_spi_data *data; + struct spi_controller *ctlr; + struct aspeed_spi *aspi; + struct resource *res; + int ret; + + data = of_device_get_match_data(&pdev->dev); + if (!data) + return -ENODEV; + + ctlr = devm_spi_alloc_master(dev, sizeof(*aspi)); + if (!ctlr) + return -ENOMEM; + + aspi = spi_controller_get_devdata(ctlr); + platform_set_drvdata(pdev, aspi); + aspi->data = data; + aspi->dev = dev; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + aspi->regs = devm_ioremap_resource(dev, res); + if (IS_ERR(aspi->regs)) { + dev_err(dev, "missing AHB register window\n"); + return PTR_ERR(aspi->regs); + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + aspi->ahb_base = devm_ioremap_resource(dev, res); + if (IS_ERR(aspi->ahb_base)) { + dev_err(dev, "missing AHB mapping window\n"); + return PTR_ERR(aspi->ahb_base); + } + + aspi->ahb_window_size = resource_size(res); + aspi->ahb_base_phy = res->start; + + aspi->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(aspi->clk)) { + dev_err(dev, "missing clock\n"); + return PTR_ERR(aspi->clk); + } + + aspi->clk_freq = clk_get_rate(aspi->clk); + if (!aspi->clk_freq) { + dev_err(dev, "invalid clock\n"); + return -EINVAL; + } + + ret = clk_prepare_enable(aspi->clk); + if (ret) { + dev_err(dev, "can not enable the clock\n"); + return ret; + } + + /* IRQ is for DMA, which the driver doesn't support yet */ + + ctlr->mode_bits = SPI_RX_DUAL | SPI_TX_DUAL | data->mode_bits; + ctlr->bus_num = pdev->id; + ctlr->mem_ops = &aspeed_spi_mem_ops; + ctlr->setup = aspeed_spi_setup; + ctlr->cleanup = aspeed_spi_cleanup; + ctlr->num_chipselect = data->max_cs; + ctlr->dev.of_node = dev->of_node; + + ret = devm_spi_register_controller(dev, ctlr); + if (ret) { + dev_err(&pdev->dev, "spi_register_controller failed\n"); + goto disable_clk; + } + return 0; + +disable_clk: + clk_disable_unprepare(aspi->clk); + return ret; +} + +static int aspeed_spi_remove(struct platform_device *pdev) +{ + struct aspeed_spi *aspi = platform_get_drvdata(pdev); + + aspeed_spi_enable(aspi, false); + clk_disable_unprepare(aspi->clk); + return 0; +} + +/* + * AHB mappings + */ + +/* + * The Segment Registers of the AST2400 and AST2500 use a 8MB unit. + * The address range is encoded with absolute addresses in the overall + * mapping window. + */ +static u32 aspeed_spi_segment_start(struct aspeed_spi *aspi, u32 reg) +{ + return ((reg >> 16) & 0xFF) << 23; +} + +static u32 aspeed_spi_segment_end(struct aspeed_spi *aspi, u32 reg) +{ + return ((reg >> 24) & 0xFF) << 23; +} + +static u32 aspeed_spi_segment_reg(struct aspeed_spi *aspi, u32 start, u32 end) +{ + return (((start >> 23) & 0xFF) << 16) | (((end >> 23) & 0xFF) << 24); +} + +/* + * The Segment Registers of the AST2600 use a 1MB unit. The address + * range is encoded with offsets in the overall mapping window. + */ + +#define AST2600_SEG_ADDR_MASK 0x0ff00000 + +static u32 aspeed_spi_segment_ast2600_start(struct aspeed_spi *aspi, + u32 reg) +{ + u32 start_offset = (reg << 16) & AST2600_SEG_ADDR_MASK; + + return aspi->ahb_base_phy + start_offset; +} + +static u32 aspeed_spi_segment_ast2600_end(struct aspeed_spi *aspi, + u32 reg) +{ + u32 end_offset = reg & AST2600_SEG_ADDR_MASK; + + /* segment is disabled */ + if (!end_offset) + return aspi->ahb_base_phy; + + return aspi->ahb_base_phy + end_offset + 0x100000; +} + +static u32 aspeed_spi_segment_ast2600_reg(struct aspeed_spi *aspi, + u32 start, u32 end) +{ + /* disable zero size segments */ + if (start == end) + return 0; + + return ((start & AST2600_SEG_ADDR_MASK) >> 16) | + ((end - 1) & AST2600_SEG_ADDR_MASK); +} + +/* + * Read timing compensation sequences + */ + +#define CALIBRATE_BUF_SIZE SZ_16K + +static bool aspeed_spi_check_reads(struct aspeed_spi_chip *chip, + const u8 *golden_buf, u8 *test_buf) +{ + int i; + + for (i = 0; i < 10; i++) { + memcpy_fromio(test_buf, chip->ahb_base, CALIBRATE_BUF_SIZE); + if (memcmp(test_buf, golden_buf, CALIBRATE_BUF_SIZE) != 0) { +#if defined(VERBOSE_DEBUG) + print_hex_dump_bytes(DEVICE_NAME " fail: ", DUMP_PREFIX_NONE, + test_buf, 0x100); +#endif + return false; + } + } + return true; +} + +#define FREAD_TPASS(i) (((i) / 2) | (((i) & 1) ? 0 : 8)) + +/* + * The timing register is shared by all devices. Only update for CE0. + */ +static int aspeed_spi_calibrate(struct aspeed_spi_chip *chip, u32 hdiv, + const u8 *golden_buf, u8 *test_buf) +{ + struct aspeed_spi *aspi = chip->aspi; + const struct aspeed_spi_data *data = aspi->data; + int i; + int good_pass = -1, pass_count = 0; + u32 shift = (hdiv - 1) << 2; + u32 mask = ~(0xfu << shift); + u32 fread_timing_val = 0; + + /* Try HCLK delay 0..5, each one with/without delay and look for a + * good pair. + */ + for (i = 0; i < 12; i++) { + bool pass; + + if (chip->cs == 0) { + fread_timing_val &= mask; + fread_timing_val |= FREAD_TPASS(i) << shift; + writel(fread_timing_val, aspi->regs + data->timing); + } + pass = aspeed_spi_check_reads(chip, golden_buf, test_buf); + dev_dbg(aspi->dev, + " * [%08x] %d HCLK delay, %dns DI delay : %s", + fread_timing_val, i / 2, (i & 1) ? 0 : 4, + pass ? "PASS" : "FAIL"); + if (pass) { + pass_count++; + if (pass_count == 3) { + good_pass = i - 1; + break; + } + } else { + pass_count = 0; + } + } + + /* No good setting for this frequency */ + if (good_pass < 0) + return -1; + + /* We have at least one pass of margin, let's use first pass */ + if (chip->cs == 0) { + fread_timing_val &= mask; + fread_timing_val |= FREAD_TPASS(good_pass) << shift; + writel(fread_timing_val, aspi->regs + data->timing); + } + dev_dbg(aspi->dev, " * -> good is pass %d [0x%08x]", + good_pass, fread_timing_val); + return 0; +} + +static bool aspeed_spi_check_calib_data(const u8 *test_buf, u32 size) +{ + const u32 *tb32 = (const u32 *)test_buf; + u32 i, cnt = 0; + + /* We check if we have enough words that are neither all 0 + * nor all 1's so the calibration can be considered valid. + * + * I use an arbitrary threshold for now of 64 + */ + size >>= 2; + for (i = 0; i < size; i++) { + if (tb32[i] != 0 && tb32[i] != 0xffffffff) + cnt++; + } + return cnt >= 64; +} + +static const u32 aspeed_spi_hclk_divs[] = { + 0xf, /* HCLK */ + 0x7, /* HCLK/2 */ + 0xe, /* HCLK/3 */ + 0x6, /* HCLK/4 */ + 0xd, /* HCLK/5 */ +}; + +#define ASPEED_SPI_HCLK_DIV(i) \ + (aspeed_spi_hclk_divs[(i) - 1] << CTRL_FREQ_SEL_SHIFT) + +static int aspeed_spi_do_calibration(struct aspeed_spi_chip *chip) +{ + struct aspeed_spi *aspi = chip->aspi; + const struct aspeed_spi_data *data = aspi->data; + u32 ahb_freq = aspi->clk_freq; + u32 max_freq = chip->clk_freq; + u32 ctl_val; + u8 *golden_buf = NULL; + u8 *test_buf = NULL; + int i, rc, best_div = -1; + + dev_dbg(aspi->dev, "calculate timing compensation - AHB freq: %d MHz", + ahb_freq / 1000000); + + /* + * use the related low frequency to get check calibration data + * and get golden data. + */ + ctl_val = chip->ctl_val[ASPEED_SPI_READ] & data->hclk_mask; + writel(ctl_val, chip->ctl); + + test_buf = kzalloc(CALIBRATE_BUF_SIZE * 2, GFP_KERNEL); + if (!test_buf) + return -ENOMEM; + + golden_buf = test_buf + CALIBRATE_BUF_SIZE; + + memcpy_fromio(golden_buf, chip->ahb_base, CALIBRATE_BUF_SIZE); + if (!aspeed_spi_check_calib_data(golden_buf, CALIBRATE_BUF_SIZE)) { + dev_info(aspi->dev, "Calibration area too uniform, using low speed"); + goto no_calib; + } + +#if defined(VERBOSE_DEBUG) + print_hex_dump_bytes(DEVICE_NAME " good: ", DUMP_PREFIX_NONE, + golden_buf, 0x100); +#endif + + /* Now we iterate the HCLK dividers until we find our breaking point */ + for (i = ARRAY_SIZE(aspeed_spi_hclk_divs); i > data->hdiv_max - 1; i--) { + u32 tv, freq; + + freq = ahb_freq / i; + if (freq > max_freq) + continue; + + /* Set the timing */ + tv = chip->ctl_val[ASPEED_SPI_READ] | ASPEED_SPI_HCLK_DIV(i); + writel(tv, chip->ctl); + dev_dbg(aspi->dev, "Trying HCLK/%d [%08x] ...", i, tv); + rc = data->calibrate(chip, i, golden_buf, test_buf); + if (rc == 0) + best_div = i; + } + + /* Nothing found ? */ + if (best_div < 0) { + dev_warn(aspi->dev, "No good frequency, using dumb slow"); + } else { + dev_dbg(aspi->dev, "Found good read timings at HCLK/%d", best_div); + + /* Record the freq */ + for (i = 0; i < ASPEED_SPI_MAX; i++) + chip->ctl_val[i] = (chip->ctl_val[i] & data->hclk_mask) | + ASPEED_SPI_HCLK_DIV(best_div); + } + +no_calib: + writel(chip->ctl_val[ASPEED_SPI_READ], chip->ctl); + kfree(test_buf); + return 0; +} + +#define TIMING_DELAY_DI BIT(3) +#define TIMING_DELAY_HCYCLE_MAX 5 +#define TIMING_REG_AST2600(chip) \ + ((chip)->aspi->regs + (chip)->aspi->data->timing + \ + (chip)->cs * 4) + +static int aspeed_spi_ast2600_calibrate(struct aspeed_spi_chip *chip, u32 hdiv, + const u8 *golden_buf, u8 *test_buf) +{ + struct aspeed_spi *aspi = chip->aspi; + int hcycle; + u32 shift = (hdiv - 2) << 3; + u32 mask = ~(0xfu << shift); + u32 fread_timing_val = 0; + + for (hcycle = 0; hcycle <= TIMING_DELAY_HCYCLE_MAX; hcycle++) { + int delay_ns; + bool pass = false; + + fread_timing_val &= mask; + fread_timing_val |= hcycle << shift; + + /* no DI input delay first */ + writel(fread_timing_val, TIMING_REG_AST2600(chip)); + pass = aspeed_spi_check_reads(chip, golden_buf, test_buf); + dev_dbg(aspi->dev, + " * [%08x] %d HCLK delay, DI delay none : %s", + fread_timing_val, hcycle, pass ? "PASS" : "FAIL"); + if (pass) + return 0; + + /* Add DI input delays */ + fread_timing_val &= mask; + fread_timing_val |= (TIMING_DELAY_DI | hcycle) << shift; + + for (delay_ns = 0; delay_ns < 0x10; delay_ns++) { + fread_timing_val &= ~(0xf << (4 + shift)); + fread_timing_val |= delay_ns << (4 + shift); + + writel(fread_timing_val, TIMING_REG_AST2600(chip)); + pass = aspeed_spi_check_reads(chip, golden_buf, test_buf); + dev_dbg(aspi->dev, + " * [%08x] %d HCLK delay, DI delay %d.%dns : %s", + fread_timing_val, hcycle, (delay_ns + 1) / 2, + (delay_ns + 1) & 1 ? 5 : 5, pass ? "PASS" : "FAIL"); + /* + * TODO: This is optimistic. We should look + * for a working interval and save the middle + * value in the read timing register. + */ + if (pass) + return 0; + } + } + + /* No good setting for this frequency */ + return -1; +} + +/* + * Platform definitions + */ +static const struct aspeed_spi_data ast2400_fmc_data = { + .max_cs = 5, + .hastype = true, + .we0 = 16, + .ctl0 = CE0_CTRL_REG, + .timing = CE0_TIMING_COMPENSATION_REG, + .hclk_mask = 0xfffff0ff, + .hdiv_max = 1, + .calibrate = aspeed_spi_calibrate, + .segment_start = aspeed_spi_segment_start, + .segment_end = aspeed_spi_segment_end, + .segment_reg = aspeed_spi_segment_reg, +}; + +static const struct aspeed_spi_data ast2400_spi_data = { + .max_cs = 1, + .hastype = false, + .we0 = 0, + .ctl0 = 0x04, + .timing = 0x14, + .hclk_mask = 0xfffff0ff, + .hdiv_max = 1, + .calibrate = aspeed_spi_calibrate, + /* No segment registers */ +}; + +static const struct aspeed_spi_data ast2500_fmc_data = { + .max_cs = 3, + .hastype = true, + .we0 = 16, + .ctl0 = CE0_CTRL_REG, + .timing = CE0_TIMING_COMPENSATION_REG, + .hclk_mask = 0xffffd0ff, + .hdiv_max = 1, + .calibrate = aspeed_spi_calibrate, + .segment_start = aspeed_spi_segment_start, + .segment_end = aspeed_spi_segment_end, + .segment_reg = aspeed_spi_segment_reg, +}; + +static const struct aspeed_spi_data ast2500_spi_data = { + .max_cs = 2, + .hastype = false, + .we0 = 16, + .ctl0 = CE0_CTRL_REG, + .timing = CE0_TIMING_COMPENSATION_REG, + .hclk_mask = 0xffffd0ff, + .hdiv_max = 1, + .calibrate = aspeed_spi_calibrate, + .segment_start = aspeed_spi_segment_start, + .segment_end = aspeed_spi_segment_end, + .segment_reg = aspeed_spi_segment_reg, +}; + +static const struct aspeed_spi_data ast2600_fmc_data = { + .max_cs = 3, + .hastype = false, + .mode_bits = SPI_RX_QUAD | SPI_RX_QUAD, + .we0 = 16, + .ctl0 = CE0_CTRL_REG, + .timing = CE0_TIMING_COMPENSATION_REG, + .hclk_mask = 0xf0fff0ff, + .hdiv_max = 2, + .calibrate = aspeed_spi_ast2600_calibrate, + .segment_start = aspeed_spi_segment_ast2600_start, + .segment_end = aspeed_spi_segment_ast2600_end, + .segment_reg = aspeed_spi_segment_ast2600_reg, +}; + +static const struct aspeed_spi_data ast2600_spi_data = { + .max_cs = 2, + .hastype = false, + .mode_bits = SPI_RX_QUAD | SPI_RX_QUAD, + .we0 = 16, + .ctl0 = CE0_CTRL_REG, + .timing = CE0_TIMING_COMPENSATION_REG, + .hclk_mask = 0xf0fff0ff, + .hdiv_max = 2, + .calibrate = aspeed_spi_ast2600_calibrate, + .segment_start = aspeed_spi_segment_ast2600_start, + .segment_end = aspeed_spi_segment_ast2600_end, + .segment_reg = aspeed_spi_segment_ast2600_reg, +}; + +static const struct of_device_id aspeed_spi_matches[] = { + { .compatible = "aspeed,ast2400-fmc", .data = &ast2400_fmc_data }, + { .compatible = "aspeed,ast2400-spi", .data = &ast2400_spi_data }, + { .compatible = "aspeed,ast2500-fmc", .data = &ast2500_fmc_data }, + { .compatible = "aspeed,ast2500-spi", .data = &ast2500_spi_data }, + { .compatible = "aspeed,ast2600-fmc", .data = &ast2600_fmc_data }, + { .compatible = "aspeed,ast2600-spi", .data = &ast2600_spi_data }, + { } +}; +MODULE_DEVICE_TABLE(of, aspeed_spi_matches); + +static struct platform_driver aspeed_spi_driver = { + .probe = aspeed_spi_probe, + .remove = aspeed_spi_remove, + .driver = { + .name = DEVICE_NAME, + .of_match_table = aspeed_spi_matches, + } +}; + +module_platform_driver(aspeed_spi_driver); + +MODULE_DESCRIPTION("ASPEED Static Memory Controller Driver"); +MODULE_AUTHOR("Chin-Ting Kuo <chin-ting_kuo@aspeedtech.com>"); +MODULE_AUTHOR("Cedric Le Goater <clg@kaod.org>"); +MODULE_LICENSE("GPL v2"); |