[U-Boot] [PATCH v5 2/4] spi: Add SiFive SPI driver
Jagan Teki
jagan at amarulasolutions.com
Wed Jul 17 04:01:44 UTC 2019
On Wed, Jul 17, 2019 at 9:20 AM Anup Patel <Anup.Patel at wdc.com> wrote:
>
> From: Bhargav Shah <bhargavshah1988 at gmail.com>
>
> This patch adds SiFive SPI driver. The driver is 100% DM driver
> and it determines input clock using clk framework.
>
> The SiFive SPI block is found on SiFive FU540 SOC and is used to
> access flash and MMC devices on SiFive Unleashed board.
>
> This driver implementation is inspired from the Linux SiFive SPI
> driver available in Linux-5.2 or higher and SiFive FSBL sources.
>
> Signed-off-by: Bhargav Shah <bhargavshah1988 at gmail.com>
> Signed-off-by: Anup Patel <anup.patel at wdc.com>
> Reviewed-by: Bin Meng <bmeng.cn at gmail.com>
> Tested-by: Bin Meng <bmeng.cn at gmail.com>
> ---
> drivers/spi/Kconfig | 8 +
> drivers/spi/Makefile | 1 +
> drivers/spi/spi-sifive.c | 375 +++++++++++++++++++++++++++++++++++++++
> 3 files changed, 384 insertions(+)
> create mode 100644 drivers/spi/spi-sifive.c
>
> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> index eb32f082fe..030f3377d4 100644
> --- a/drivers/spi/Kconfig
> +++ b/drivers/spi/Kconfig
> @@ -224,6 +224,14 @@ 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 8be9a4baa2..a53b9f4217 100644
> --- a/drivers/spi/Makefile
> +++ b/drivers/spi/Makefile
> @@ -49,6 +49,7 @@ 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..08f30f3f21
> --- /dev/null
> +++ b/drivers/spi/spi-sifive.c
> @@ -0,0 +1,375 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright 2018 SiFive, Inc.
> + * Copyright 2019 Bhargav Shah <bhargavshah1988 at 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->cs > spi->num_cs)
> + return -EINVAL;
Move this to cs_info.
> +
> + 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_claim_bus(struct udevice *dev)
> +{
> + /* Nothing to do here. */
> + return 0;
> +}
> +
> +static int sifive_spi_release_bus(struct udevice *dev)
> +{
> + /* Nothing to do here. */
> + return 0;
> +}
dummy won't need as spi-uclass.c return 0 if none hooked.
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