This driver is a simplified version of linux/drivers/spi/spi-bcm63xx.c Instead of supporting both HW revisions of the controller in a single build, support has been split by the selected config to save space.
Signed-off-by: Álvaro Fernández Rojas noltari@gmail.com --- drivers/spi/Kconfig | 23 +++ drivers/spi/Makefile | 1 + drivers/spi/bcm63xx_spi.c | 404 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 428 insertions(+) create mode 100644 drivers/spi/bcm63xx_spi.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index a00d401..d458dd7 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -43,6 +43,29 @@ config ATMEL_SPI many AT32 (AVR32) and AT91 (ARM) chips. This driver can be used to access the SPI Flash, such as AT25DF321.
+choice + prompt "BCM63xx SPI driver" + depends on ARCH_BMIPS + optional + +config BCM6338_SPI + bool "BCM6338 SPI driver" + select SPI_MAX_WRITE_CMD_BYTES + help + Enable the BCM6338 SPI driver. This driver can be used to + access the SPI NOR flash on platforms embedding this Broadcom + SPI core. + +config BCM6358_SPI + bool "BCM6358 SPI driver" + select SPI_MAX_WRITE_CMD_BYTES + help + Enable the BCM6358 SPI driver. This driver can be used to + access the SPI NOR flash on platforms embedding this Broadcom + SPI core. + +endchoice + config CADENCE_QSPI bool "Cadence QSPI driver" help diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index c090562..c9ba648 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_ALTERA_SPI) += altera_spi.o obj-$(CONFIG_ATH79_SPI) += ath79_spi.o obj-$(CONFIG_ATMEL_DATAFLASH_SPI) += atmel_dataflash_spi.o obj-$(CONFIG_ATMEL_SPI) += atmel_spi.o +obj-$(CONFIG_BCM6338_SPI)$(CONFIG_BCM6358_SPI) += bcm63xx_spi.o obj-$(CONFIG_CADENCE_QSPI) += cadence_qspi.o cadence_qspi_apb.o obj-$(CONFIG_CF_SPI) += cf_spi.o obj-$(CONFIG_DAVINCI_SPI) += davinci_spi.o diff --git a/drivers/spi/bcm63xx_spi.c b/drivers/spi/bcm63xx_spi.c new file mode 100644 index 0000000..6e64607 --- /dev/null +++ b/drivers/spi/bcm63xx_spi.c @@ -0,0 +1,404 @@ +/* + * Copyright (C) 2017 Álvaro Fernández Rojas noltari@gmail.com + * + * Derived from linux/drivers/spi/spi-bcm63xx.c: + * Copyright (C) 2009-2012 Florian Fainelli florian@openwrt.org + * Copyright (C) 2010 Tanguy Bouzeloc tanguy.bouzeloc@efixo.com + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <clk.h> +#include <dm.h> +#include <spi.h> +#include <reset.h> +#include <asm/io.h> + +DECLARE_GLOBAL_DATA_PTR; + +#if defined(CONFIG_BCM6338_SPI) + +# define SPI_DT_ID "brcm,bcm6338-spi" + +/* SPI Command register */ +# define SPI_CMD_REG 0x00 + +/* SPI Interrupt registers */ +# define SPI_IR_STAT_REG 0x02 +# define SPI_IR_MASK_REG 0x04 + +/* SPI Clock register */ +# define SPI_CLK_REG 0x06 + +/* SPI Fill register */ +# define SPI_FILL_REG 0x07 + +/* SPI Control register (8 bit) */ +# define SPI_CTL_REG 0x40 +# define SPI_CTL_BYTES_SHIFT 0 +# define SPI_CTL_BYTES_MASK (0x3f << SPI_CTL_BYTES_SHIFT) +# define SPI_CTL_TYPE_SHIFT 6 +# define SPI_CTL_TYPE_FD_RW (0 << SPI_CTL_TYPE_SHIFT) +# define SPI_CTL_TYPE_HD_W (1 << SPI_CTL_TYPE_SHIFT) +# define SPI_CTL_TYPE_HD_R (2 << SPI_CTL_TYPE_SHIFT) + +# define bcm63xx_spi_wctl(v,a) writeb_be(v, a); + +/* SPI TX Data registers */ +# define SPI_TX_DATA_REG 0x41 +# define SPI_TX_DATA_SIZE 0x3f + +/* SPI RX Data registers */ +# define SPI_RX_DATA_REG 0x80 +# define SPI_RX_DATA_SIZE 0x3f + +#elif defined(CONFIG_BCM6358_SPI) + +# define SPI_DT_ID "brcm,bcm6358-spi" + +/* SPI Control register (16 bit) */ +# define SPI_CTL_REG 0x000 +# define SPI_CTL_BYTES_SHIFT 0 +# define SPI_CTL_BYTES_MASK (0x3ff << SPI_CTL_BYTES_SHIFT) +# define SPI_CTL_TYPE_SHIFT 14 +# define SPI_CTL_TYPE_FD_RW (0 << SPI_CTL_TYPE_SHIFT) +# define SPI_CTL_TYPE_HD_W (1 << SPI_CTL_TYPE_SHIFT) +# define SPI_CTL_TYPE_HD_R (2 << SPI_CTL_TYPE_SHIFT) + +# define bcm63xx_spi_wctl(v,a) writew_be(v, a); + +/* SPI TX Data registers */ +# define SPI_TX_DATA_REG 0x002 +# define SPI_TX_DATA_SIZE 0x21e + +/* SPI RX Data registers */ +# define SPI_RX_DATA_REG 0x400 +# define SPI_RX_DATA_SIZE 0x220 + +/* SPI Command register */ +# define SPI_CMD_REG 0x700 + +/* SPI Interrupt registers */ +# define SPI_IR_STAT_REG 0x702 +# define SPI_IR_MASK_REG 0x704 + +/* SPI Clock register */ +# define SPI_CLK_REG 0x706 + +/* SPI Fill register */ +# define SPI_FILL_REG 0x707 + +#endif + +/* SPI Command register */ +#define SPI_CMD_OP_SHIFT 0 +#define SPI_CMD_OP_START (0x3 << SPI_CMD_OP_SHIFT) +#define SPI_CMD_SLAVE_SHIFT 4 +#define SPI_CMD_SLAVE_MASK (0xf << SPI_CMD_SLAVE_SHIFT) +#define SPI_CMD_PREPEND_SHIFT 8 +#define SPI_CMD_PREPEND_BYTES 0xf +#define SPI_CMD_3WIRE_SHIFT 12 +#define SPI_CMD_3WIRE_MASK (1 << SPI_CMD_3WIRE_SHIFT) + +/* SPI Interrupt registers */ +#define SPI_IR_DONE_SHIFT 0 +#define SPI_IR_DONE_MASK (1 << SPI_IR_DONE_SHIFT) +#define SPI_IR_RXOVER_SHIFT 1 +#define SPI_IR_RXOVER_MASK (1 << SPI_IR_RXOVER_SHIFT) +#define SPI_IR_TXUNDER_SHIFT 2 +#define SPI_IR_TXUNDER_MASK (1 << SPI_IR_TXUNDER_SHIFT) +#define SPI_IR_TXOVER_SHIFT 3 +#define SPI_IR_TXOVER_MASK (1 << SPI_IR_TXOVER_SHIFT) +#define SPI_IR_RXUNDER_SHIFT 4 +#define SPI_IR_RXUNDER_MASK (1 << SPI_IR_RXUNDER_SHIFT) +#define SPI_IR_CLEAR_MASK (SPI_IR_DONE_MASK |\ + SPI_IR_RXOVER_MASK |\ + SPI_IR_TXUNDER_MASK |\ + SPI_IR_TXOVER_MASK |\ + SPI_IR_RXUNDER_MASK) + +/* SPI Clock register */ +#define SPI_CLK_SHIFT 0 +#define SPI_CLK_20MHZ (0 << SPI_CLK_SHIFT) +#define SPI_CLK_0_391MHZ (1 << SPI_CLK_SHIFT) +#define SPI_CLK_0_781MHZ (2 << SPI_CLK_SHIFT) +#define SPI_CLK_1_563MHZ (3 << SPI_CLK_SHIFT) +#define SPI_CLK_3_125MHZ (4 << SPI_CLK_SHIFT) +#define SPI_CLK_6_250MHZ (5 << SPI_CLK_SHIFT) +#define SPI_CLK_12_50MHZ (6 << SPI_CLK_SHIFT) +#define SPI_CLK_25MHZ (7 << SPI_CLK_SHIFT) +#define SPI_CLK_MASK (7 << SPI_CLK_SHIFT) +#define SPI_CLK_SSOFF_SHIFT 3 +#define SPI_CLK_SSOFF_2 (2 << SPI_CLK_SSOFF_SHIFT) +#define SPI_CLK_SSOFF_MASK (7 << SPI_CLK_SSOFF_SHIFT) +#define SPI_CLK_BSWAP_SHIFT 7 +#define SPI_CLK_BSWAP_MASK (1 << SPI_CLK_BSWAP_SHIFT) + +#define SPI_CLK_CNT 8 +static const unsigned bcm63xx_spi_freq_table[SPI_CLK_CNT][2] = { + { 25000000, SPI_CLK_25MHZ }, + { 20000000, SPI_CLK_20MHZ }, + { 12500000, SPI_CLK_12_50MHZ }, + { 6250000, SPI_CLK_6_250MHZ }, + { 3125000, SPI_CLK_3_125MHZ }, + { 1563000, SPI_CLK_1_563MHZ }, + { 781000, SPI_CLK_0_781MHZ }, + { 391000, SPI_CLK_0_391MHZ } +}; + +struct bcm63xx_spi_priv { + void __iomem *regs; + uint8_t num_cs; + size_t tx_bytes; +}; + +static int bcm63xx_spi_cs_info(struct udevice *bus, uint cs, + struct spi_cs_info *info) +{ + struct bcm63xx_spi_priv *priv = dev_get_priv(bus); + + if (cs >= priv->num_cs) { + error("no cs %u\n", cs); + return -ENODEV; + } + + return 0; +} + +static int bcm63xx_spi_set_mode(struct udevice *bus, uint mode) +{ + struct bcm63xx_spi_priv *priv = dev_get_priv(bus); + + if (mode & SPI_LSB_FIRST) + setbits_8(priv->regs + SPI_CLK_REG, SPI_CLK_BSWAP_MASK); + else + clrbits_8(priv->regs + SPI_CLK_REG, SPI_CLK_BSWAP_MASK); + + return 0; +} + +static int bcm63xx_spi_set_speed(struct udevice *bus, uint speed) +{ + struct bcm63xx_spi_priv *priv = dev_get_priv(bus); + uint8_t clk_cfg; + int i; + + /* default to lowest clock configuration */ + clk_cfg = SPI_CLK_0_391MHZ; + + /* find the closest clock configuration */ + for (i = 0; i < SPI_CLK_CNT; i++) { + if (speed >= bcm63xx_spi_freq_table[i][0]) { + clk_cfg = bcm63xx_spi_freq_table[i][1]; + break; + } + } + + /* write clock configuration */ + clrsetbits_8(priv->regs + SPI_CLK_REG, + SPI_CLK_SSOFF_MASK | SPI_CLK_MASK, + clk_cfg | SPI_CLK_SSOFF_2); + + return 0; +} + +/* + * BCM63xx SPI driver doesn't allow keeping CS active between transfers since + * they are HW controlled. + * However, it provides a mechanism to prepend write transfers prior to read + * transfers (with a maximum prepend of 15 bytes), which is usually enough for + * SPI-connected flashes since reading requires prepending a write transfer of + * 5 bytes. + * + * This implementation takes advantage of the prepend mechanism and combines + * multiple transfers into a single one where possible (single/multiple write + * transfer(s) followed by a final read/write transfer). + * However, it's not possible to buffer reads, which means that read transfers + * should always be done as the final ones. + * On the other hand, take into account that combining write transfers into + * a single one is just buffering and doesn't require prepend mechanism. + */ +static int bcm63xx_spi_xfer(struct udevice *dev, unsigned int bitlen, + const void *dout, void *din, unsigned long flags) +{ + struct bcm63xx_spi_priv *priv = dev_get_priv(dev->parent); + size_t data_bytes = bitlen / 8; + + if (flags & SPI_XFER_BEGIN) { + /* clear prepends */ + priv->tx_bytes = 0; + + /* initialize hardware */ + writeb_be(0, priv->regs + SPI_IR_MASK_REG); + } + + if (din) { + /* buffering reads not possible since cs is hw controlled */ + if (!(flags & SPI_XFER_END)) { + error("unable to buffer reads\n"); + return -EINVAL; + } + + /* check rx size */ + if (data_bytes > SPI_RX_DATA_SIZE) { + error("max rx bytes exceeded\n"); + return -EMSGSIZE; + } + } + + if (dout) { + /* check tx size */ + if (priv->tx_bytes + data_bytes > SPI_TX_DATA_SIZE) { + error("max tx bytes exceeded\n"); + return -EMSGSIZE; + } + + /* copy tx data */ + memcpy_toio(priv->regs + SPI_TX_DATA_REG + priv->tx_bytes, + dout, data_bytes); + priv->tx_bytes += data_bytes; + } + + if (flags & SPI_XFER_END) { + struct dm_spi_slave_platdata *plat = + dev_get_parent_platdata(dev); + uint16_t val = 0; + uint8_t irq; + + /* determine control config */ + if (dout && !din) { + /* buffered write transfers */ + val |= (priv->tx_bytes << SPI_CTL_BYTES_SHIFT); + val |= SPI_CTL_TYPE_HD_W; + priv->tx_bytes = 0; + } else { + if (dout && din && (flags & SPI_XFER_ONCE)) { + /* full duplex read/write */ + val |= (data_bytes << SPI_CTL_BYTES_SHIFT); + val |= SPI_CTL_TYPE_FD_RW; + priv->tx_bytes = 0; + } else { + /* prepended write transfer */ + val |= (data_bytes << SPI_CTL_BYTES_SHIFT); + val |= SPI_CTL_TYPE_HD_R; + if (priv->tx_bytes > SPI_CMD_PREPEND_BYTES) { + error("max prepend bytes exceeded\n"); + return -EMSGSIZE; + } + } + } + bcm63xx_spi_wctl(val, priv->regs + SPI_CTL_REG); + + /* clear interrupts */ + writeb_be(SPI_IR_CLEAR_MASK, priv->regs + SPI_IR_STAT_REG); + + /* issue the transfer */ + val = SPI_CMD_OP_START; + val |= (plat->cs << SPI_CMD_SLAVE_SHIFT) & SPI_CMD_SLAVE_MASK; + val |= (priv->tx_bytes << SPI_CMD_PREPEND_SHIFT); + if (plat->mode & SPI_3WIRE) + val |= SPI_CMD_3WIRE_MASK; + writew_be(val, priv->regs + SPI_CMD_REG); + + /* enable interrupts */ + writeb_be(SPI_IR_DONE_MASK, priv->regs + SPI_IR_MASK_REG); + + do { + /* read interupts */ + irq = readb_be(priv->regs + SPI_IR_STAT_REG); + + /* transfer completed */ + if (irq & SPI_IR_DONE_MASK) + break; + } while (1); + + /* copy rx data */ + if (din) + memcpy_fromio(din, priv->regs + SPI_RX_DATA_REG, + data_bytes); + } + + return 0; +} + +static const struct dm_spi_ops bcm63xx_spi_ops = { + .cs_info = bcm63xx_spi_cs_info, + .set_mode = bcm63xx_spi_set_mode, + .set_speed = bcm63xx_spi_set_speed, + .xfer = bcm63xx_spi_xfer, +}; + +static const struct udevice_id bcm63xx_spi_ids[] = { + { .compatible = SPI_DT_ID, }, + { /* sentinel */ } +}; + +static int bcm63xx_spi_child_pre_probe(struct udevice *dev) +{ + struct bcm63xx_spi_priv *priv = dev_get_priv(dev->parent); + struct spi_slave *slave = dev_get_parent_priv(dev); + struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev); + + /* check cs */ + if (plat->cs >= priv->num_cs) { + error("no cs %u\n", plat->cs); + return -ENODEV; + } + + /* max read/write sizes */ + slave->max_read_size = SPI_RX_DATA_SIZE; + slave->max_write_size = SPI_TX_DATA_SIZE; + + return 0; +} + +static int bcm63xx_spi_probe(struct udevice *dev) +{ + struct bcm63xx_spi_priv *priv = dev_get_priv(dev); + struct reset_ctl rst_ctl; + struct clk clk; + fdt_addr_t addr; + fdt_size_t size; + int ret; + + addr = dev_get_addr_size_index(dev, 0, &size); + if (addr == FDT_ADDR_T_NONE) + return -EINVAL; + + priv->regs = ioremap(addr, size); + priv->num_cs = fdtdec_get_uint(gd->fdt_blob, dev_of_offset(dev), + "num-cs", 8); + + /* enable clock */ + ret = clk_get_by_index(dev, 0, &clk); + if (ret < 0) + return ret; + clk_enable(&clk); + clk_free(&clk); + + /* perform reset */ + ret = reset_get_by_index(dev, 0, &rst_ctl); + if (ret < 0) + return ret; + reset_deassert(&rst_ctl); + reset_free(&rst_ctl); + + /* initialize hardware */ + writeb_be(0, priv->regs + SPI_IR_MASK_REG); + + /* set fill register */ + writeb_be(0xff, priv->regs + SPI_FILL_REG); + + return 0; +} + +U_BOOT_DRIVER(bcm63xx_spi) = { + .name = "bcm63xx_spi", + .id = UCLASS_SPI, + .of_match = bcm63xx_spi_ids, + .ops = &bcm63xx_spi_ops, + .priv_auto_alloc_size = sizeof(struct bcm63xx_spi_priv), + .child_pre_probe = bcm63xx_spi_child_pre_probe, + .probe = bcm63xx_spi_probe, +};