diff options
-rw-r--r-- | drivers/spi/Kconfig | 8 | ||||
-rw-r--r-- | drivers/spi/Makefile | 1 | ||||
-rw-r--r-- | drivers/spi/spi-sifive.c | 370 |
3 files changed, 379 insertions, 0 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index cc174dd036..2ee0ac976d 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -232,6 +232,14 @@ config SANDBOX_SPI }; }; +config SPI_SIFIVE + bool "SiFive SPI driver" + help + This driver supports the SiFive SPI IP. If unsure say N. + Enable the SiFive SPI controller driver. + + The SiFive SPI controller driver is found on various SiFive SoCs. + config SPI_SUNXI bool "Allwinner SoC SPI controllers" help diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index ab84122f08..d0ebaf339a 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -50,6 +50,7 @@ obj-$(CONFIG_PL022_SPI) += pl022_spi.o obj-$(CONFIG_RENESAS_RPC_SPI) += renesas_rpc_spi.o obj-$(CONFIG_ROCKCHIP_SPI) += rk_spi.o obj-$(CONFIG_SANDBOX_SPI) += sandbox_spi.o +obj-$(CONFIG_SPI_SIFIVE) += spi-sifive.o obj-$(CONFIG_SPI_SUNXI) += spi-sunxi.o obj-$(CONFIG_SH_SPI) += sh_spi.o obj-$(CONFIG_SH_QSPI) += sh_qspi.o diff --git a/drivers/spi/spi-sifive.c b/drivers/spi/spi-sifive.c new file mode 100644 index 0000000000..969bd4b75c --- /dev/null +++ b/drivers/spi/spi-sifive.c @@ -0,0 +1,370 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2018 SiFive, Inc. + * Copyright 2019 Bhargav Shah <bhargavshah1988@gmail.com> + * + * SiFive SPI controller driver (master mode only) + */ + +#include <common.h> +#include <dm.h> +#include <malloc.h> +#include <spi.h> +#include <asm/io.h> +#include <linux/log2.h> +#include <clk.h> + +#define SIFIVE_SPI_MAX_CS 32 + +#define SIFIVE_SPI_DEFAULT_DEPTH 8 +#define SIFIVE_SPI_DEFAULT_BITS 8 + +/* register offsets */ +#define SIFIVE_SPI_REG_SCKDIV 0x00 /* Serial clock divisor */ +#define SIFIVE_SPI_REG_SCKMODE 0x04 /* Serial clock mode */ +#define SIFIVE_SPI_REG_CSID 0x10 /* Chip select ID */ +#define SIFIVE_SPI_REG_CSDEF 0x14 /* Chip select default */ +#define SIFIVE_SPI_REG_CSMODE 0x18 /* Chip select mode */ +#define SIFIVE_SPI_REG_DELAY0 0x28 /* Delay control 0 */ +#define SIFIVE_SPI_REG_DELAY1 0x2c /* Delay control 1 */ +#define SIFIVE_SPI_REG_FMT 0x40 /* Frame format */ +#define SIFIVE_SPI_REG_TXDATA 0x48 /* Tx FIFO data */ +#define SIFIVE_SPI_REG_RXDATA 0x4c /* Rx FIFO data */ +#define SIFIVE_SPI_REG_TXMARK 0x50 /* Tx FIFO watermark */ +#define SIFIVE_SPI_REG_RXMARK 0x54 /* Rx FIFO watermark */ +#define SIFIVE_SPI_REG_FCTRL 0x60 /* SPI flash interface control */ +#define SIFIVE_SPI_REG_FFMT 0x64 /* SPI flash instruction format */ +#define SIFIVE_SPI_REG_IE 0x70 /* Interrupt Enable Register */ +#define SIFIVE_SPI_REG_IP 0x74 /* Interrupt Pendings Register */ + +/* sckdiv bits */ +#define SIFIVE_SPI_SCKDIV_DIV_MASK 0xfffU + +/* sckmode bits */ +#define SIFIVE_SPI_SCKMODE_PHA BIT(0) +#define SIFIVE_SPI_SCKMODE_POL BIT(1) +#define SIFIVE_SPI_SCKMODE_MODE_MASK (SIFIVE_SPI_SCKMODE_PHA | \ + SIFIVE_SPI_SCKMODE_POL) + +/* csmode bits */ +#define SIFIVE_SPI_CSMODE_MODE_AUTO 0U +#define SIFIVE_SPI_CSMODE_MODE_HOLD 2U +#define SIFIVE_SPI_CSMODE_MODE_OFF 3U + +/* delay0 bits */ +#define SIFIVE_SPI_DELAY0_CSSCK(x) ((u32)(x)) +#define SIFIVE_SPI_DELAY0_CSSCK_MASK 0xffU +#define SIFIVE_SPI_DELAY0_SCKCS(x) ((u32)(x) << 16) +#define SIFIVE_SPI_DELAY0_SCKCS_MASK (0xffU << 16) + +/* delay1 bits */ +#define SIFIVE_SPI_DELAY1_INTERCS(x) ((u32)(x)) +#define SIFIVE_SPI_DELAY1_INTERCS_MASK 0xffU +#define SIFIVE_SPI_DELAY1_INTERXFR(x) ((u32)(x) << 16) +#define SIFIVE_SPI_DELAY1_INTERXFR_MASK (0xffU << 16) + +/* fmt bits */ +#define SIFIVE_SPI_FMT_PROTO_SINGLE 0U +#define SIFIVE_SPI_FMT_PROTO_DUAL 1U +#define SIFIVE_SPI_FMT_PROTO_QUAD 2U +#define SIFIVE_SPI_FMT_PROTO_MASK 3U +#define SIFIVE_SPI_FMT_ENDIAN BIT(2) +#define SIFIVE_SPI_FMT_DIR BIT(3) +#define SIFIVE_SPI_FMT_LEN(x) ((u32)(x) << 16) +#define SIFIVE_SPI_FMT_LEN_MASK (0xfU << 16) + +/* txdata bits */ +#define SIFIVE_SPI_TXDATA_DATA_MASK 0xffU +#define SIFIVE_SPI_TXDATA_FULL BIT(31) + +/* rxdata bits */ +#define SIFIVE_SPI_RXDATA_DATA_MASK 0xffU +#define SIFIVE_SPI_RXDATA_EMPTY BIT(31) + +/* ie and ip bits */ +#define SIFIVE_SPI_IP_TXWM BIT(0) +#define SIFIVE_SPI_IP_RXWM BIT(1) + +struct sifive_spi { + void *regs; /* base address of the registers */ + u32 fifo_depth; + u32 bits_per_word; + u32 cs_inactive; /* Level of the CS pins when inactive*/ + u32 freq; + u32 num_cs; +}; + +static void sifive_spi_prep_device(struct sifive_spi *spi, + struct dm_spi_slave_platdata *slave) +{ + /* Update the chip select polarity */ + if (slave->mode & SPI_CS_HIGH) + spi->cs_inactive &= ~BIT(slave->cs); + else + spi->cs_inactive |= BIT(slave->cs); + writel(spi->cs_inactive, spi->regs + SIFIVE_SPI_REG_CSDEF); + + /* Select the correct device */ + writel(slave->cs, spi->regs + SIFIVE_SPI_REG_CSID); +} + +static int sifive_spi_set_cs(struct sifive_spi *spi, + struct dm_spi_slave_platdata *slave) +{ + u32 cs_mode = SIFIVE_SPI_CSMODE_MODE_HOLD; + + if (slave->mode & SPI_CS_HIGH) + cs_mode = SIFIVE_SPI_CSMODE_MODE_AUTO; + + writel(cs_mode, spi->regs + SIFIVE_SPI_REG_CSMODE); + + return 0; +} + +static void sifive_spi_clear_cs(struct sifive_spi *spi) +{ + writel(SIFIVE_SPI_CSMODE_MODE_AUTO, spi->regs + SIFIVE_SPI_REG_CSMODE); +} + +static void sifive_spi_prep_transfer(struct sifive_spi *spi, + bool is_rx_xfer, + struct dm_spi_slave_platdata *slave) +{ + u32 cr; + + /* Modify the SPI protocol mode */ + cr = readl(spi->regs + SIFIVE_SPI_REG_FMT); + + /* Bits per word ? */ + cr &= ~SIFIVE_SPI_FMT_LEN_MASK; + cr |= SIFIVE_SPI_FMT_LEN(spi->bits_per_word); + + /* LSB first? */ + cr &= ~SIFIVE_SPI_FMT_ENDIAN; + if (slave->mode & SPI_LSB_FIRST) + cr |= SIFIVE_SPI_FMT_ENDIAN; + + /* Number of wires ? */ + cr &= ~SIFIVE_SPI_FMT_PROTO_MASK; + if ((slave->mode & SPI_TX_QUAD) || (slave->mode & SPI_RX_QUAD)) + cr |= SIFIVE_SPI_FMT_PROTO_QUAD; + else if ((slave->mode & SPI_TX_DUAL) || (slave->mode & SPI_RX_DUAL)) + cr |= SIFIVE_SPI_FMT_PROTO_DUAL; + else + cr |= SIFIVE_SPI_FMT_PROTO_SINGLE; + + /* SPI direction in/out ? */ + cr &= ~SIFIVE_SPI_FMT_DIR; + if (!is_rx_xfer) + cr |= SIFIVE_SPI_FMT_DIR; + + writel(cr, spi->regs + SIFIVE_SPI_REG_FMT); +} + +static void sifive_spi_rx(struct sifive_spi *spi, u8 *rx_ptr) +{ + u32 data; + + do { + data = readl(spi->regs + SIFIVE_SPI_REG_RXDATA); + } while (data & SIFIVE_SPI_RXDATA_EMPTY); + + if (rx_ptr) + *rx_ptr = data & SIFIVE_SPI_RXDATA_DATA_MASK; +} + +static void sifive_spi_tx(struct sifive_spi *spi, const u8 *tx_ptr) +{ + u32 data; + u8 tx_data = (tx_ptr) ? *tx_ptr & SIFIVE_SPI_TXDATA_DATA_MASK : + SIFIVE_SPI_TXDATA_DATA_MASK; + + do { + data = readl(spi->regs + SIFIVE_SPI_REG_TXDATA); + } while (data & SIFIVE_SPI_TXDATA_FULL); + + writel(tx_data, spi->regs + SIFIVE_SPI_REG_TXDATA); +} + +static int sifive_spi_xfer(struct udevice *dev, unsigned int bitlen, + const void *dout, void *din, unsigned long flags) +{ + struct udevice *bus = dev->parent; + struct sifive_spi *spi = dev_get_priv(bus); + struct dm_spi_slave_platdata *slave = dev_get_parent_platdata(dev); + const unsigned char *tx_ptr = dout; + u8 *rx_ptr = din; + u32 remaining_len; + int ret; + + if (flags & SPI_XFER_BEGIN) { + sifive_spi_prep_device(spi, slave); + + ret = sifive_spi_set_cs(spi, slave); + if (ret) + return ret; + } + + sifive_spi_prep_transfer(spi, true, slave); + + remaining_len = bitlen / 8; + + while (remaining_len) { + int n_words, tx_words, rx_words; + + n_words = min(remaining_len, spi->fifo_depth); + + /* Enqueue n_words for transmission */ + if (tx_ptr) { + for (tx_words = 0; tx_words < n_words; ++tx_words) { + sifive_spi_tx(spi, tx_ptr); + sifive_spi_rx(spi, NULL); + tx_ptr++; + } + } + + /* Read out all the data from the RX FIFO */ + if (rx_ptr) { + for (rx_words = 0; rx_words < n_words; ++rx_words) { + sifive_spi_tx(spi, NULL); + sifive_spi_rx(spi, rx_ptr); + rx_ptr++; + } + } + + remaining_len -= n_words; + } + + if (flags & SPI_XFER_END) + sifive_spi_clear_cs(spi); + + return 0; +} + +static int sifive_spi_set_speed(struct udevice *bus, uint speed) +{ + struct sifive_spi *spi = dev_get_priv(bus); + u32 scale; + + if (speed > spi->freq) + speed = spi->freq; + + /* Cofigure max speed */ + scale = (DIV_ROUND_UP(spi->freq >> 1, speed) - 1) + & SIFIVE_SPI_SCKDIV_DIV_MASK; + writel(scale, spi->regs + SIFIVE_SPI_REG_SCKDIV); + + return 0; +} + +static int sifive_spi_set_mode(struct udevice *bus, uint mode) +{ + struct sifive_spi *spi = dev_get_priv(bus); + u32 cr; + + /* Switch clock mode bits */ + cr = readl(spi->regs + SIFIVE_SPI_REG_SCKMODE) & + ~SIFIVE_SPI_SCKMODE_MODE_MASK; + if (mode & SPI_CPHA) + cr |= SIFIVE_SPI_SCKMODE_PHA; + if (mode & SPI_CPOL) + cr |= SIFIVE_SPI_SCKMODE_POL; + + writel(cr, spi->regs + SIFIVE_SPI_REG_SCKMODE); + + return 0; +} + +static int sifive_spi_cs_info(struct udevice *bus, uint cs, + struct spi_cs_info *info) +{ + struct sifive_spi *spi = dev_get_priv(bus); + + if (cs >= spi->num_cs) + return -EINVAL; + + return 0; +} + +static void sifive_spi_init_hw(struct sifive_spi *spi) +{ + u32 cs_bits; + + /* probe the number of CS lines */ + spi->cs_inactive = readl(spi->regs + SIFIVE_SPI_REG_CSDEF); + writel(0xffffffffU, spi->regs + SIFIVE_SPI_REG_CSDEF); + cs_bits = readl(spi->regs + SIFIVE_SPI_REG_CSDEF); + writel(spi->cs_inactive, spi->regs + SIFIVE_SPI_REG_CSDEF); + if (!cs_bits) { + printf("Could not auto probe CS lines\n"); + return; + } + + spi->num_cs = ilog2(cs_bits) + 1; + if (spi->num_cs > SIFIVE_SPI_MAX_CS) { + printf("Invalid number of spi slaves\n"); + return; + } + + /* Watermark interrupts are disabled by default */ + writel(0, spi->regs + SIFIVE_SPI_REG_IE); + + /* Set CS/SCK Delays and Inactive Time to defaults */ + writel(SIFIVE_SPI_DELAY0_CSSCK(1) | SIFIVE_SPI_DELAY0_SCKCS(1), + spi->regs + SIFIVE_SPI_REG_DELAY0); + writel(SIFIVE_SPI_DELAY1_INTERCS(1) | SIFIVE_SPI_DELAY1_INTERXFR(0), + spi->regs + SIFIVE_SPI_REG_DELAY1); + + /* Exit specialized memory-mapped SPI flash mode */ + writel(0, spi->regs + SIFIVE_SPI_REG_FCTRL); +} + +static int sifive_spi_probe(struct udevice *bus) +{ + struct sifive_spi *spi = dev_get_priv(bus); + struct clk clkdev; + int ret; + + spi->regs = (void *)(ulong)dev_remap_addr(bus); + if (!spi->regs) + return -ENODEV; + + spi->fifo_depth = dev_read_u32_default(bus, + "sifive,fifo-depth", + SIFIVE_SPI_DEFAULT_DEPTH); + + spi->bits_per_word = dev_read_u32_default(bus, + "sifive,max-bits-per-word", + SIFIVE_SPI_DEFAULT_BITS); + + ret = clk_get_by_index(bus, 0, &clkdev); + if (ret) + return ret; + spi->freq = clk_get_rate(&clkdev); + + /* init the sifive spi hw */ + sifive_spi_init_hw(spi); + + return 0; +} + +static const struct dm_spi_ops sifive_spi_ops = { + .xfer = sifive_spi_xfer, + .set_speed = sifive_spi_set_speed, + .set_mode = sifive_spi_set_mode, + .cs_info = sifive_spi_cs_info, +}; + +static const struct udevice_id sifive_spi_ids[] = { + { .compatible = "sifive,spi0" }, + { } +}; + +U_BOOT_DRIVER(sifive_spi) = { + .name = "sifive_spi", + .id = UCLASS_SPI, + .of_match = sifive_spi_ids, + .ops = &sifive_spi_ops, + .priv_auto_alloc_size = sizeof(struct sifive_spi), + .probe = sifive_spi_probe, +}; |