This driver is a simplified version of linux/drivers/spi/spi-bcm63xx.c
Signed-off-by: Álvaro Fernández Rojas noltari@gmail.com Reviewed-by: Simon Glass sjg@chromium.org Reviewed-by: Daniel Schwierzeck daniel.schwierzeck@gmail.com Reviewed-by: Jagan Teki jagan@openedev.com --- v8: no changes v7: Introduce changes suggested by Daniel Schwierzeck: - Remove prefix and use __func__ instead. v6: Introduce changes suggested by Jagan Teki: - Use cmd instead of val to avoid confusions. - Switch to wait_for_bit instead of infinite loop. v5: Introduce changes suggested by Jagan Teki: - Use long structure instead of a custom bmips_spi_hw structure. - Define constants for each SPI core. v4: Introduce changes suggested by Jagan Teki: - Add data for each HW controller instead of having two separate configs. - Also check clock and reset returns as suggested by Simon Glass for HSSPI. v3: rename BCM6338 SPI driver to BCM6348 switch to devfdt_get_addr_size_index() v2: no changes
drivers/spi/Kconfig | 8 + drivers/spi/Makefile | 1 + drivers/spi/bcm63xx_spi.c | 433 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 442 insertions(+) create mode 100644 drivers/spi/bcm63xx_spi.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 494639fb01..ebc71c2e42 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -40,6 +40,14 @@ config ATMEL_SPI many AT91 (ARM) chips. This driver can be used to access the SPI Flash, such as AT25DF321.
+config BCM63XX_SPI + bool "BCM6348 SPI driver" + depends on ARCH_BMIPS + help + Enable the BCM6348/BCM6358 SPI driver. This driver can be used to + access the SPI NOR flash on platforms embedding these Broadcom + SPI cores. + config CADENCE_QSPI bool "Cadence QSPI driver" help diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index e3184db67f..5770b3f7cc 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -18,6 +18,7 @@ endif obj-$(CONFIG_ALTERA_SPI) += altera_spi.o obj-$(CONFIG_ATH79_SPI) += ath79_spi.o obj-$(CONFIG_ATMEL_SPI) += atmel_spi.o +obj-$(CONFIG_BCM63XX_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 0000000000..f0df6871d8 --- /dev/null +++ b/drivers/spi/bcm63xx_spi.c @@ -0,0 +1,433 @@ +/* + * 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 <wait_bit.h> +#include <asm/io.h> + +DECLARE_GLOBAL_DATA_PTR; + +/* BCM6348 SPI core */ +#define SPI_6348_CLK 0x06 +#define SPI_6348_CMD 0x00 +#define SPI_6348_CTL 0x40 +#define SPI_6348_CTL_SHIFT 6 +#define SPI_6348_FILL 0x07 +#define SPI_6348_IR_MASK 0x04 +#define SPI_6348_IR_STAT 0x02 +#define SPI_6348_RX 0x80 +#define SPI_6348_RX_SIZE 0x3f +#define SPI_6348_TX 0x41 +#define SPI_6348_TX_SIZE 0x3f + +/* BCM6358 SPI core */ +#define SPI_6358_CLK 0x706 +#define SPI_6358_CMD 0x700 +#define SPI_6358_CTL 0x000 +#define SPI_6358_CTL_SHIFT 14 +#define SPI_6358_FILL 0x707 +#define SPI_6358_IR_MASK 0x702 +#define SPI_6358_IR_STAT 0x704 +#define SPI_6358_RX 0x400 +#define SPI_6358_RX_SIZE 0x220 +#define SPI_6358_TX 0x002 +#define SPI_6358_TX_SIZE 0x21e + +/* 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) + +/* 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 Control register */ +#define SPI_CTL_TYPE_FD_RW 0 +#define SPI_CTL_TYPE_HD_W 1 +#define SPI_CTL_TYPE_HD_R 2 + +/* 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) + +enum bcm63xx_regs_spi { + SPI_CLK, + SPI_CMD, + SPI_CTL, + SPI_CTL_SHIFT, + SPI_FILL, + SPI_IR_MASK, + SPI_IR_STAT, + SPI_RX, + SPI_RX_SIZE, + SPI_TX, + SPI_TX_SIZE, +}; + +struct bcm63xx_spi_priv { + const unsigned long *regs; + void __iomem *base; + size_t tx_bytes; + uint8_t num_cs; +}; + +#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 } +}; + +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) { + printf("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); + const unsigned long *regs = priv->regs; + + if (mode & SPI_LSB_FIRST) + setbits_8(priv->base + regs[SPI_CLK], SPI_CLK_BSWAP_MASK); + else + clrbits_8(priv->base + regs[SPI_CLK], 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); + const unsigned long *regs = priv->regs; + 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->base + regs[SPI_CLK], + 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); + const unsigned long *regs = priv->regs; + size_t data_bytes = bitlen / 8; + + if (flags & SPI_XFER_BEGIN) { + /* clear prepends */ + priv->tx_bytes = 0; + + /* initialize hardware */ + writeb_be(0, priv->base + regs[SPI_IR_MASK]); + } + + if (din) { + /* buffering reads not possible since cs is hw controlled */ + if (!(flags & SPI_XFER_END)) { + printf("unable to buffer reads\n"); + return -EINVAL; + } + + /* check rx size */ + if (data_bytes > regs[SPI_RX_SIZE]) { + printf("max rx bytes exceeded\n"); + return -EMSGSIZE; + } + } + + if (dout) { + /* check tx size */ + if (priv->tx_bytes + data_bytes > regs[SPI_TX_SIZE]) { + printf("max tx bytes exceeded\n"); + return -EMSGSIZE; + } + + /* copy tx data */ + memcpy_toio(priv->base + regs[SPI_TX] + 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, cmd; + int ret; + + /* determine control config */ + if (dout && !din) { + /* buffered write transfers */ + val = priv->tx_bytes; + val |= (SPI_CTL_TYPE_HD_W << regs[SPI_CTL_SHIFT]); + priv->tx_bytes = 0; + } else { + if (dout && din && (flags & SPI_XFER_ONCE)) { + /* full duplex read/write */ + val = data_bytes; + val |= (SPI_CTL_TYPE_FD_RW << + regs[SPI_CTL_SHIFT]); + priv->tx_bytes = 0; + } else { + /* prepended write transfer */ + val = data_bytes; + val |= (SPI_CTL_TYPE_HD_R << + regs[SPI_CTL_SHIFT]); + if (priv->tx_bytes > SPI_CMD_PREPEND_BYTES) { + printf("max prepend bytes exceeded\n"); + return -EMSGSIZE; + } + } + } + + if (regs[SPI_CTL_SHIFT] >= 8) + writew_be(val, priv->base + regs[SPI_CTL]); + else + writeb_be(val, priv->base + regs[SPI_CTL]); + + /* clear interrupts */ + writeb_be(SPI_IR_CLEAR_MASK, priv->base + regs[SPI_IR_STAT]); + + /* issue the transfer */ + cmd = SPI_CMD_OP_START; + cmd |= (plat->cs << SPI_CMD_SLAVE_SHIFT) & SPI_CMD_SLAVE_MASK; + cmd |= (priv->tx_bytes << SPI_CMD_PREPEND_SHIFT); + if (plat->mode & SPI_3WIRE) + cmd |= SPI_CMD_3WIRE_MASK; + writew_be(cmd, priv->base + regs[SPI_CMD]); + + /* enable interrupts */ + writeb_be(SPI_IR_DONE_MASK, priv->base + regs[SPI_IR_MASK]); + + ret = wait_for_bit_8(priv->base + regs[SPI_IR_STAT], + SPI_IR_DONE_MASK, true, 1000, false); + if (ret) { + printf("interrupt timeout\n"); + return ret; + } + + /* copy rx data */ + if (din) + memcpy_fromio(din, priv->base + regs[SPI_RX], + 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 unsigned long bcm6348_spi_regs[] = { + [SPI_CLK] = SPI_6348_CLK, + [SPI_CMD] = SPI_6348_CMD, + [SPI_CTL] = SPI_6348_CTL, + [SPI_CTL_SHIFT] = SPI_6348_CTL_SHIFT, + [SPI_FILL] = SPI_6348_FILL, + [SPI_IR_MASK] = SPI_6348_IR_MASK, + [SPI_IR_STAT] = SPI_6348_IR_STAT, + [SPI_RX] = SPI_6348_RX, + [SPI_RX_SIZE] = SPI_6348_RX_SIZE, + [SPI_TX] = SPI_6348_TX, + [SPI_TX_SIZE] = SPI_6348_TX_SIZE, +}; + +static const unsigned long bcm6358_spi_regs[] = { + [SPI_CLK] = SPI_6358_CLK, + [SPI_CMD] = SPI_6358_CMD, + [SPI_CTL] = SPI_6358_CTL, + [SPI_CTL_SHIFT] = SPI_6358_CTL_SHIFT, + [SPI_FILL] = SPI_6358_FILL, + [SPI_IR_MASK] = SPI_6358_IR_MASK, + [SPI_IR_STAT] = SPI_6358_IR_STAT, + [SPI_RX] = SPI_6358_RX, + [SPI_RX_SIZE] = SPI_6358_RX_SIZE, + [SPI_TX] = SPI_6358_TX, + [SPI_TX_SIZE] = SPI_6358_TX_SIZE, +}; + +static const struct udevice_id bcm63xx_spi_ids[] = { + { + .compatible = "brcm,bcm6348-spi", + .data = (ulong)&bcm6348_spi_regs, + }, { + .compatible = "brcm,bcm6358-spi", + .data = (ulong)&bcm6358_spi_regs, + }, { /* sentinel */ } +}; + +static int bcm63xx_spi_child_pre_probe(struct udevice *dev) +{ + struct bcm63xx_spi_priv *priv = dev_get_priv(dev->parent); + const unsigned long *regs = priv->regs; + 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) { + printf("no cs %u\n", plat->cs); + return -ENODEV; + } + + /* max read/write sizes */ + slave->max_read_size = regs[SPI_RX_SIZE]; + slave->max_write_size = regs[SPI_TX_SIZE]; + + return 0; +} + +static int bcm63xx_spi_probe(struct udevice *dev) +{ + struct bcm63xx_spi_priv *priv = dev_get_priv(dev); + const unsigned long *regs = + (const unsigned long *)dev_get_driver_data(dev); + struct reset_ctl rst_ctl; + struct clk clk; + fdt_addr_t addr; + fdt_size_t size; + int ret; + + addr = devfdt_get_addr_size_index(dev, 0, &size); + if (addr == FDT_ADDR_T_NONE) + return -EINVAL; + + priv->regs = regs; + priv->base = 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; + + ret = clk_enable(&clk); + if (ret < 0) + return ret; + + ret = clk_free(&clk); + if (ret < 0) + return ret; + + /* perform reset */ + ret = reset_get_by_index(dev, 0, &rst_ctl); + if (ret < 0) + return ret; + + ret = reset_deassert(&rst_ctl); + if (ret < 0) + return ret; + + ret = reset_free(&rst_ctl); + if (ret < 0) + return ret; + + /* initialize hardware */ + writeb_be(0, priv->base + regs[SPI_IR_MASK]); + + /* set fill register */ + writeb_be(0xff, priv->base + regs[SPI_FILL]); + + 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, +};