diff options
Diffstat (limited to 'drivers/spi/cadence_qspi.c')
| -rw-r--r-- | drivers/spi/cadence_qspi.c | 345 |
1 files changed, 345 insertions, 0 deletions
diff --git a/drivers/spi/cadence_qspi.c b/drivers/spi/cadence_qspi.c new file mode 100644 index 0000000000..fa95b19ecd --- /dev/null +++ b/drivers/spi/cadence_qspi.c @@ -0,0 +1,345 @@ +/* + * Copyright (C) 2012 + * Altera Corporation <www.altera.com> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <dm.h> +#include <fdtdec.h> +#include <malloc.h> +#include <spi.h> +#include <asm/errno.h> +#include "cadence_qspi.h" + +#define CQSPI_STIG_READ 0 +#define CQSPI_STIG_WRITE 1 +#define CQSPI_INDIRECT_READ 2 +#define CQSPI_INDIRECT_WRITE 3 + +DECLARE_GLOBAL_DATA_PTR; + +static int cadence_spi_write_speed(struct udevice *bus, uint hz) +{ + struct cadence_spi_platdata *plat = bus->platdata; + struct cadence_spi_priv *priv = dev_get_priv(bus); + + cadence_qspi_apb_config_baudrate_div(priv->regbase, + CONFIG_CQSPI_REF_CLK, hz); + + /* Reconfigure delay timing if speed is changed. */ + cadence_qspi_apb_delay(priv->regbase, CONFIG_CQSPI_REF_CLK, hz, + plat->tshsl_ns, plat->tsd2d_ns, + plat->tchsh_ns, plat->tslch_ns); + + return 0; +} + +/* Calibration sequence to determine the read data capture delay register */ +static int spi_calibration(struct udevice *bus) +{ + struct cadence_spi_platdata *plat = bus->platdata; + struct cadence_spi_priv *priv = dev_get_priv(bus); + void *base = priv->regbase; + u8 opcode_rdid = 0x9F; + unsigned int idcode = 0, temp = 0; + int err = 0, i, range_lo = -1, range_hi = -1; + + /* start with slowest clock (1 MHz) */ + cadence_spi_write_speed(bus, 1000000); + + /* configure the read data capture delay register to 0 */ + cadence_qspi_apb_readdata_capture(base, 1, 0); + + /* Enable QSPI */ + cadence_qspi_apb_controller_enable(base); + + /* read the ID which will be our golden value */ + err = cadence_qspi_apb_command_read(base, 1, &opcode_rdid, + 3, (u8 *)&idcode); + if (err) { + puts("SF: Calibration failed (read)\n"); + return err; + } + + /* use back the intended clock and find low range */ + cadence_spi_write_speed(bus, plat->max_hz); + for (i = 0; i < CQSPI_READ_CAPTURE_MAX_DELAY; i++) { + /* Disable QSPI */ + cadence_qspi_apb_controller_disable(base); + + /* reconfigure the read data capture delay register */ + cadence_qspi_apb_readdata_capture(base, 1, i); + + /* Enable back QSPI */ + cadence_qspi_apb_controller_enable(base); + + /* issue a RDID to get the ID value */ + err = cadence_qspi_apb_command_read(base, 1, &opcode_rdid, + 3, (u8 *)&temp); + if (err) { + puts("SF: Calibration failed (read)\n"); + return err; + } + + /* search for range lo */ + if (range_lo == -1 && temp == idcode) { + range_lo = i; + continue; + } + + /* search for range hi */ + if (range_lo != -1 && temp != idcode) { + range_hi = i - 1; + break; + } + range_hi = i; + } + + if (range_lo == -1) { + puts("SF: Calibration failed (low range)\n"); + return err; + } + + /* Disable QSPI for subsequent initialization */ + cadence_qspi_apb_controller_disable(base); + + /* configure the final value for read data capture delay register */ + cadence_qspi_apb_readdata_capture(base, 1, (range_hi + range_lo) / 2); + debug("SF: Read data capture delay calibrated to %i (%i - %i)\n", + (range_hi + range_lo) / 2, range_lo, range_hi); + + /* just to ensure we do once only when speed or chip select change */ + priv->qspi_calibrated_hz = plat->max_hz; + priv->qspi_calibrated_cs = spi_chip_select(bus); + + return 0; +} + +static int cadence_spi_set_speed(struct udevice *bus, uint hz) +{ + struct cadence_spi_platdata *plat = bus->platdata; + struct cadence_spi_priv *priv = dev_get_priv(bus); + int err; + + /* Disable QSPI */ + cadence_qspi_apb_controller_disable(priv->regbase); + + cadence_spi_write_speed(bus, hz); + + /* Calibration required for different SCLK speed or chip select */ + if (priv->qspi_calibrated_hz != plat->max_hz || + priv->qspi_calibrated_cs != spi_chip_select(bus)) { + err = spi_calibration(bus); + if (err) + return err; + } + + /* Enable QSPI */ + cadence_qspi_apb_controller_enable(priv->regbase); + + debug("%s: speed=%d\n", __func__, hz); + + return 0; +} + +static int cadence_spi_probe(struct udevice *bus) +{ + struct cadence_spi_platdata *plat = bus->platdata; + struct cadence_spi_priv *priv = dev_get_priv(bus); + + priv->regbase = plat->regbase; + priv->ahbbase = plat->ahbbase; + + if (!priv->qspi_is_init) { + cadence_qspi_apb_controller_init(plat); + priv->qspi_is_init = 1; + } + + return 0; +} + +static int cadence_spi_set_mode(struct udevice *bus, uint mode) +{ + struct cadence_spi_priv *priv = dev_get_priv(bus); + unsigned int clk_pol = (mode & SPI_CPOL) ? 1 : 0; + unsigned int clk_pha = (mode & SPI_CPHA) ? 1 : 0; + + /* Disable QSPI */ + cadence_qspi_apb_controller_disable(priv->regbase); + + /* Set SPI mode */ + cadence_qspi_apb_set_clk_mode(priv->regbase, clk_pol, clk_pha); + + /* Enable QSPI */ + cadence_qspi_apb_controller_enable(priv->regbase); + + return 0; +} + +static int cadence_spi_xfer(struct udevice *dev, unsigned int bitlen, + const void *dout, void *din, unsigned long flags) +{ + struct udevice *bus = dev->parent; + struct cadence_spi_platdata *plat = bus->platdata; + struct cadence_spi_priv *priv = dev_get_priv(bus); + void *base = priv->regbase; + u8 *cmd_buf = priv->cmd_buf; + size_t data_bytes; + int err = 0; + u32 mode = CQSPI_STIG_WRITE; + + if (flags & SPI_XFER_BEGIN) { + /* copy command to local buffer */ + priv->cmd_len = bitlen / 8; + memcpy(cmd_buf, dout, priv->cmd_len); + } + + if (flags == (SPI_XFER_BEGIN | SPI_XFER_END)) { + /* if start and end bit are set, the data bytes is 0. */ + data_bytes = 0; + } else { + data_bytes = bitlen / 8; + } + debug("%s: len=%d [bytes]\n", __func__, data_bytes); + + /* Set Chip select */ + cadence_qspi_apb_chipselect(base, spi_chip_select(dev), + CONFIG_CQSPI_DECODER); + + if ((flags & SPI_XFER_END) || (flags == 0)) { + if (priv->cmd_len == 0) { + printf("QSPI: Error, command is empty.\n"); + return -1; + } + + if (din && data_bytes) { + /* read */ + /* Use STIG if no address. */ + if (!CQSPI_IS_ADDR(priv->cmd_len)) + mode = CQSPI_STIG_READ; + else + mode = CQSPI_INDIRECT_READ; + } else if (dout && !(flags & SPI_XFER_BEGIN)) { + /* write */ + if (!CQSPI_IS_ADDR(priv->cmd_len)) + mode = CQSPI_STIG_WRITE; + else + mode = CQSPI_INDIRECT_WRITE; + } + + switch (mode) { + case CQSPI_STIG_READ: + err = cadence_qspi_apb_command_read( + base, priv->cmd_len, cmd_buf, + data_bytes, din); + + break; + case CQSPI_STIG_WRITE: + err = cadence_qspi_apb_command_write(base, + priv->cmd_len, cmd_buf, + data_bytes, dout); + break; + case CQSPI_INDIRECT_READ: + err = cadence_qspi_apb_indirect_read_setup(plat, + priv->cmd_len, cmd_buf); + if (!err) { + err = cadence_qspi_apb_indirect_read_execute + (plat, data_bytes, din); + } + break; + case CQSPI_INDIRECT_WRITE: + err = cadence_qspi_apb_indirect_write_setup + (plat, priv->cmd_len, cmd_buf); + if (!err) { + err = cadence_qspi_apb_indirect_write_execute + (plat, data_bytes, dout); + } + break; + default: + err = -1; + break; + } + + if (flags & SPI_XFER_END) { + /* clear command buffer */ + memset(cmd_buf, 0, sizeof(priv->cmd_buf)); + priv->cmd_len = 0; + } + } + + return err; +} + +static int cadence_spi_ofdata_to_platdata(struct udevice *bus) +{ + struct cadence_spi_platdata *plat = bus->platdata; + const void *blob = gd->fdt_blob; + int node = bus->of_offset; + int subnode; + u32 data[4]; + int ret; + + /* 2 base addresses are needed, lets get them from the DT */ + ret = fdtdec_get_int_array(blob, node, "reg", data, ARRAY_SIZE(data)); + if (ret) { + printf("Error: Can't get base addresses (ret=%d)!\n", ret); + return -ENODEV; + } + + plat->regbase = (void *)data[0]; + plat->ahbbase = (void *)data[2]; + + /* Use 500KHz as a suitable default */ + plat->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency", + 500000); + + /* All other paramters are embedded in the child node */ + subnode = fdt_first_subnode(blob, node); + if (!subnode) { + printf("Error: subnode with SPI flash config missing!\n"); + return -ENODEV; + } + + /* Read other parameters from DT */ + plat->page_size = fdtdec_get_int(blob, subnode, "page-size", 256); + plat->block_size = fdtdec_get_int(blob, subnode, "block-size", 16); + plat->tshsl_ns = fdtdec_get_int(blob, subnode, "tshsl-ns", 200); + plat->tsd2d_ns = fdtdec_get_int(blob, subnode, "tsd2d-ns", 255); + plat->tchsh_ns = fdtdec_get_int(blob, subnode, "tchsh-ns", 20); + plat->tslch_ns = fdtdec_get_int(blob, subnode, "tslch-ns", 20); + + debug("%s: regbase=%p ahbbase=%p max-frequency=%d page-size=%d\n", + __func__, plat->regbase, plat->ahbbase, plat->max_hz, + plat->page_size); + + return 0; +} + +static const struct dm_spi_ops cadence_spi_ops = { + .xfer = cadence_spi_xfer, + .set_speed = cadence_spi_set_speed, + .set_mode = cadence_spi_set_mode, + /* + * cs_info is not needed, since we require all chip selects to be + * in the device tree explicitly + */ +}; + +static const struct udevice_id cadence_spi_ids[] = { + { .compatible = "cadence,qspi" }, + { } +}; + +U_BOOT_DRIVER(cadence_spi) = { + .name = "cadence_spi", + .id = UCLASS_SPI, + .of_match = cadence_spi_ids, + .ops = &cadence_spi_ops, + .ofdata_to_platdata = cadence_spi_ofdata_to_platdata, + .platdata_auto_alloc_size = sizeof(struct cadence_spi_platdata), + .priv_auto_alloc_size = sizeof(struct cadence_spi_priv), + .per_child_auto_alloc_size = sizeof(struct spi_slave), + .probe = cadence_spi_probe, +}; |
