| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * Copyright (c) 2006 Ben Warren, Qstreams Networks Inc. |
| * With help from the common/soft_spi and arch/powerpc/cpu/mpc8260 drivers |
| */ |
| |
| #include <clk.h> |
| #include <dm.h> |
| #include <errno.h> |
| #include <log.h> |
| #include <malloc.h> |
| #include <spi.h> |
| #include <asm/mpc8xxx_spi.h> |
| #include <asm-generic/gpio.h> |
| #include <dm/device_compat.h> |
| #include <linux/bitops.h> |
| #include <linux/delay.h> |
| #include <asm/arch/soc.h> |
| |
| enum { |
| SPI_EV_NE = BIT(31 - 22), /* Receiver Not Empty */ |
| SPI_EV_NF = BIT(31 - 23), /* Transmitter Not Full */ |
| }; |
| |
| enum { |
| SPI_MODE_LOOP = BIT(31 - 1), /* Loopback mode */ |
| SPI_MODE_CI = BIT(31 - 2), /* Clock invert */ |
| SPI_MODE_CP = BIT(31 - 3), /* Clock phase */ |
| SPI_MODE_DIV16 = BIT(31 - 4), /* Divide clock source by 16 */ |
| SPI_MODE_REV = BIT(31 - 5), /* Reverse mode - MSB first */ |
| SPI_MODE_MS = BIT(31 - 6), /* Always master */ |
| SPI_MODE_EN = BIT(31 - 7), /* Enable interface */ |
| SPI_MODE_OP = BIT(31 - 17), /* CPU Mode, QE otherwise */ |
| |
| SPI_MODE_LEN_MASK = 0xf00000, |
| SPI_MODE_LEN_SHIFT = 20, |
| SPI_MODE_PM_SHIFT = 16, |
| SPI_MODE_PM_MASK = 0xf0000, |
| |
| SPI_COM_LST = BIT(31 - 9), |
| }; |
| |
| struct mpc8xxx_priv { |
| spi8xxx_t *spi; |
| struct gpio_desc gpios[16]; |
| int cs_count; |
| ulong clk_rate; |
| }; |
| |
| #define SPI_TIMEOUT 1000 |
| |
| static int mpc8xxx_spi_of_to_plat(struct udevice *dev) |
| { |
| struct mpc8xxx_priv *priv = dev_get_priv(dev); |
| struct clk clk; |
| int ret; |
| |
| priv->spi = dev_read_addr_ptr(dev); |
| |
| ret = gpio_request_list_by_name(dev, "gpios", priv->gpios, |
| ARRAY_SIZE(priv->gpios), GPIOD_IS_OUT | GPIOD_ACTIVE_LOW); |
| if (ret < 0) |
| return -EINVAL; |
| |
| priv->cs_count = ret; |
| |
| ret = clk_get_by_index(dev, 0, &clk); |
| if (ret) { |
| dev_err(dev, "%s: clock not defined\n", __func__); |
| return ret; |
| } |
| |
| priv->clk_rate = clk_get_rate(&clk); |
| if (!priv->clk_rate) { |
| dev_err(dev, "%s: failed to get clock rate\n", __func__); |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| static int mpc8xxx_spi_probe(struct udevice *dev) |
| { |
| struct mpc8xxx_priv *priv = dev_get_priv(dev); |
| spi8xxx_t *spi = priv->spi; |
| |
| /* |
| * SPI pins on the MPC83xx are not muxed, so all we do is initialize |
| * some registers |
| */ |
| out_be32(&priv->spi->mode, SPI_MODE_REV | SPI_MODE_MS); |
| |
| if (dev_get_driver_data(dev) == SOC_MPC832X) |
| setbits_be32(&priv->spi->mode, SPI_MODE_OP); |
| |
| /* set len to 8 bits */ |
| setbits_be32(&spi->mode, (8 - 1) << SPI_MODE_LEN_SHIFT); |
| |
| setbits_be32(&spi->mode, SPI_MODE_EN); |
| |
| /* Clear all SPI events */ |
| setbits_be32(&priv->spi->event, 0xffffffff); |
| /* Mask all SPI interrupts */ |
| clrbits_be32(&priv->spi->mask, 0xffffffff); |
| /* LST bit doesn't do anything, so disregard */ |
| out_be32(&priv->spi->com, 0); |
| |
| return 0; |
| } |
| |
| static void mpc8xxx_spi_cs_activate(struct udevice *dev) |
| { |
| struct mpc8xxx_priv *priv = dev_get_priv(dev->parent); |
| struct dm_spi_slave_plat *plat = dev_get_parent_plat(dev); |
| |
| dm_gpio_set_value(&priv->gpios[plat->cs], 1); |
| } |
| |
| static void mpc8xxx_spi_cs_deactivate(struct udevice *dev) |
| { |
| struct mpc8xxx_priv *priv = dev_get_priv(dev->parent); |
| struct dm_spi_slave_plat *plat = dev_get_parent_plat(dev); |
| |
| dm_gpio_set_value(&priv->gpios[plat->cs], 0); |
| } |
| |
| static int mpc8xxx_spi_xfer(struct udevice *dev, uint bitlen, |
| const void *dout, void *din, ulong flags) |
| { |
| struct udevice *bus = dev->parent; |
| struct mpc8xxx_priv *priv = dev_get_priv(bus); |
| spi8xxx_t *spi = priv->spi; |
| struct dm_spi_slave_plat *plat = dev_get_parent_plat(dev); |
| u32 tmpdin = 0, tmpdout = 0, n; |
| const u8 *cout = dout; |
| u8 *cin = din; |
| ulong type = dev_get_driver_data(bus); |
| |
| debug("%s: slave %s:%u dout %08X din %08X bitlen %u\n", __func__, |
| bus->name, plat->cs, (uint)dout, (uint)din, bitlen); |
| if (plat->cs >= priv->cs_count) { |
| dev_err(dev, "chip select index %d too large (cs_count=%d)\n", |
| plat->cs, priv->cs_count); |
| return -EINVAL; |
| } |
| if (bitlen % 8) { |
| printf("*** spi_xfer: bitlen must be multiple of 8\n"); |
| return -ENOTSUPP; |
| } |
| |
| if (flags & SPI_XFER_BEGIN) |
| mpc8xxx_spi_cs_activate(dev); |
| |
| /* Clear all SPI events */ |
| setbits_be32(&spi->event, 0xffffffff); |
| n = bitlen / 8; |
| |
| /* Handle data in 8-bit chunks */ |
| while (n--) { |
| ulong start; |
| |
| if (cout) |
| tmpdout = *cout++; |
| |
| if (type == SOC_MPC832X) |
| tmpdout <<= 24; |
| |
| /* Write the data out */ |
| out_be32(&spi->tx, tmpdout); |
| |
| debug("*** %s: ... %08x written\n", __func__, tmpdout); |
| |
| /* |
| * Wait for SPI transmit to get out |
| * or time out (1 second = 1000 ms) |
| * The NE event must be read and cleared first |
| */ |
| start = get_timer(0); |
| do { |
| u32 event = in_be32(&spi->event); |
| bool have_ne = event & SPI_EV_NE; |
| bool have_nf = event & SPI_EV_NF; |
| |
| if (!have_ne) |
| continue; |
| |
| tmpdin = in_be32(&spi->rx); |
| setbits_be32(&spi->event, SPI_EV_NE); |
| |
| if (type == SOC_MPC832X) |
| tmpdin >>= 16; |
| |
| if (cin) |
| *cin++ = tmpdin; |
| |
| /* |
| * Only bail when we've had both NE and NF events. |
| * This will cause timeouts on RO devices, so maybe |
| * in the future put an arbitrary delay after writing |
| * the device. Arbitrary delays suck, though... |
| */ |
| if (have_nf) |
| break; |
| |
| mdelay(1); |
| } while (get_timer(start) < SPI_TIMEOUT); |
| |
| if (get_timer(start) >= SPI_TIMEOUT) { |
| debug("*** %s: Time out during SPI transfer\n", |
| __func__); |
| return -ETIMEDOUT; |
| } |
| |
| debug("*** %s: transfer ended. Value=%08x\n", __func__, tmpdin); |
| } |
| |
| if (flags & SPI_XFER_END) |
| mpc8xxx_spi_cs_deactivate(dev); |
| |
| return 0; |
| } |
| |
| static int mpc8xxx_spi_set_speed(struct udevice *dev, uint speed) |
| { |
| struct mpc8xxx_priv *priv = dev_get_priv(dev); |
| spi8xxx_t *spi = priv->spi; |
| u32 bits, mask, div16, pm; |
| u32 mode; |
| ulong clk; |
| |
| clk = priv->clk_rate; |
| if (clk / 64 > speed) { |
| div16 = SPI_MODE_DIV16; |
| clk /= 16; |
| } else { |
| div16 = 0; |
| } |
| pm = (clk - 1)/(4*speed) + 1; |
| if (pm > 16) { |
| dev_err(dev, "requested speed %u too small\n", speed); |
| return -EINVAL; |
| } |
| pm--; |
| |
| bits = div16 | (pm << SPI_MODE_PM_SHIFT); |
| mask = SPI_MODE_DIV16 | SPI_MODE_PM_MASK; |
| mode = in_be32(&spi->mode); |
| if ((mode & mask) != bits) { |
| /* Must clear mode[EN] while changing speed. */ |
| mode &= ~(mask | SPI_MODE_EN); |
| out_be32(&spi->mode, mode); |
| mode |= bits; |
| out_be32(&spi->mode, mode); |
| mode |= SPI_MODE_EN; |
| out_be32(&spi->mode, mode); |
| } |
| |
| debug("requested speed %u, set speed to %lu/(%s4*%u) == %lu\n", |
| speed, priv->clk_rate, div16 ? "16*" : "", pm + 1, |
| clk/(4*(pm + 1))); |
| |
| return 0; |
| } |
| |
| static int mpc8xxx_spi_set_mode(struct udevice *dev, uint mode) |
| { |
| /* TODO(mario.six@gdsys.cc): Using SPI_CPHA (for clock phase) and |
| * SPI_CPOL (for clock polarity) should work |
| */ |
| return 0; |
| } |
| |
| static const struct dm_spi_ops mpc8xxx_spi_ops = { |
| .xfer = mpc8xxx_spi_xfer, |
| .set_speed = mpc8xxx_spi_set_speed, |
| .set_mode = mpc8xxx_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 mpc8xxx_spi_ids[] = { |
| { .compatible = "fsl,spi" }, |
| { .compatible = "fsl,mpc832x-spi", .data = SOC_MPC832X }, |
| { } |
| }; |
| |
| U_BOOT_DRIVER(mpc8xxx_spi) = { |
| .name = "mpc8xxx_spi", |
| .id = UCLASS_SPI, |
| .of_match = mpc8xxx_spi_ids, |
| .ops = &mpc8xxx_spi_ops, |
| .of_to_plat = mpc8xxx_spi_of_to_plat, |
| .probe = mpc8xxx_spi_probe, |
| .priv_auto = sizeof(struct mpc8xxx_priv), |
| }; |