This driver is a simplified version of linux/drivers/spi/spi-bcm63xx-hsspi.c
Signed-off-by: Álvaro Fernández Rojas noltari@gmail.com --- v2: Introduce changes suggested by Simon Glass: - Split bcm63xx_hsspi_xfer() into smaller functions. - Check possible clock errors. - Check possible reset errors. - Switch to devfdt_get_addr_size_index(). - Use setbits32_be() for clock gate.
drivers/spi/Kconfig | 8 + drivers/spi/Makefile | 1 + drivers/spi/bcm63xx_hsspi.c | 413 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 422 insertions(+) create mode 100644 drivers/spi/bcm63xx_hsspi.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 0b408db..e49ec36 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -40,6 +40,14 @@ config ATMEL_SPI many AT32 (AVR32) and AT91 (ARM) chips. This driver can be used to access the SPI Flash, such as AT25DF321.
+config BCM6328_HSSPI + bool "BCM6328 HSSPI driver" + depends on ARCH_BMIPS + help + Enable the BCM6328 HSSPI driver. This driver can be used to + access the SPI NOR flash on platforms embedding this Broadcom + SPI core. + choice prompt "BCM63xx SPI driver" depends on ARCH_BMIPS diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 2795a34..7ad0da1 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-$(CONFIG_BCM6328_HSSPI) += bcm63xx_hsspi.o obj-$(CONFIG_BCM6348_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 diff --git a/drivers/spi/bcm63xx_hsspi.c b/drivers/spi/bcm63xx_hsspi.c new file mode 100644 index 0000000..538c4ec --- /dev/null +++ b/drivers/spi/bcm63xx_hsspi.c @@ -0,0 +1,413 @@ +/* + * Copyright (C) 2017 Álvaro Fernández Rojas noltari@gmail.com + * + * Derived from linux/drivers/spi/spi-bcm63xx-hsspi.c: + * Copyright (C) 2000-2010 Broadcom Corporation + * Copyright (C) 2012-2013 Jonas Gorski jogo@openwrt.org + * + * 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; + +#define SPI_PP_SEL 0 + +#define SPI_MAX_SYNC_CLOCK 30000000 + +/* SPI Control register */ +#define SPI_CTL_REG 0x000 +#define SPI_CTL_CS_POL_SHIFT 0 +#define SPI_CTL_CS_POL_MASK (0xff << SPI_CTL_CS_POL_SHIFT) +#define SPI_CTL_CLK_GATE_SHIFT 16 +#define SPI_CTL_CLK_GATE_MASK (1 << SPI_CTL_CLK_GATE_SHIFT) +#define SPI_CTL_CLK_POL_SHIFT 17 +#define SPI_CTL_CLK_POL_MASK (1 << SPI_CTL_CLK_POL_SHIFT) + +/* SPI Interrupts registers */ +#define SPI_IR_STAT_REG 0x008 +#define SPI_IR_ST_MASK_REG 0x00c +#define SPI_IR_MASK_REG 0x010 + +#define SPI_IR_CLEAR_ALL 0xff001f1f + +/* SPI Ping-Pong Command registers */ +#define SPI_PP_CMD_REG (0x080 + (0x40 * (SPI_PP_SEL)) + 0x00) +#define SPI_PP_CMD_OP_SHIFT 0 +#define SPI_PP_CMD_OP_START (0x1 << SPI_PP_CMD_OP_SHIFT) +#define SPI_PP_CMD_PFL_SHIFT 8 +#define SPI_PP_CMD_PFL_MASK (0x7 << SPI_PP_CMD_PFL_SHIFT) +#define SPI_PP_CMD_SLAVE_SHIFT 12 +#define SPI_PP_CMD_SLAVE_MASK (0x7 << SPI_PP_CMD_SLAVE_SHIFT) + +/* SPI Ping-Pong Status registers */ +#define SPI_PP_STAT_REG (0x080 + (0x40 * (SPI_PP_SEL)) + 0x04) +#define SPI_PP_STAT_SRCBUSY_SHIFT 1 +#define SPI_PP_STAT_SRCBUSY_MASK (1 << SPI_PP_STAT_SRCBUSY_SHIFT) + +/* SPI Profile Clock registers */ +#define SPI_PFL_CLK_REG(x) (0x100 + (0x20 * (x)) + 0x00) +#define SPI_PFL_CLK_FREQ_SHIFT 0 +#define SPI_PFL_CLK_FREQ_MASK (0x3fff << SPI_PFL_CLK_FREQ_SHIFT) +#define SPI_PFL_CLK_RSTLOOP_SHIFT 15 +#define SPI_PFL_CLK_RSTLOOP_MASK (1 << SPI_PFL_CLK_RSTLOOP_SHIFT) + +/* SPI Profile Signal registers */ +#define SPI_PFL_SIG_REG(x) (0x100 + (0x20 * (x)) + 0x04) +#define SPI_PFL_SIG_LATCHRIS_SHIFT 12 +#define SPI_PFL_SIG_LATCHRIS_MASK (1 << SPI_PFL_SIG_LATCHRIS_SHIFT) +#define SPI_PFL_SIG_LAUNCHRIS_SHIFT 13 +#define SPI_PFL_SIG_LAUNCHRIS_MASK (1 << SPI_PFL_SIG_LAUNCHRIS_SHIFT) +#define SPI_PFL_SIG_ASYNCIN_SHIFT 16 +#define SPI_PFL_SIG_ASYNCIN_MASK (1 << SPI_PFL_SIG_ASYNCIN_SHIFT) + +/* SPI Profile Mode registers */ +#define SPI_PFL_MODE_REG(x) (0x100 + (0x20 * (x)) + 0x08) +#define SPI_PFL_MODE_FILL_SHIFT 0 +#define SPI_PFL_MODE_FILL_MASK (0xff << SPI_PFL_MODE_FILL_SHIFT) +#define SPI_PFL_MODE_MDRDSZ_SHIFT 16 +#define SPI_PFL_MODE_MDRDSZ_MASK (1 << SPI_PFL_MODE_MDRDSZ_SHIFT) +#define SPI_PFL_MODE_MDWRSZ_SHIFT 18 +#define SPI_PFL_MODE_MDWRSZ_MASK (1 << SPI_PFL_MODE_MDWRSZ_SHIFT) +#define SPI_PFL_MODE_3WIRE_SHIFT 20 +#define SPI_PFL_MODE_3WIRE_MASK (1 << SPI_PFL_MODE_3WIRE_SHIFT) + +/* SPI Ping-Pong FIFO registers */ +#define SPI_PP_FIFO_SIZE 0x200 +#define SPI_PP_FIFO_BASE (0x200 + \ + (SPI_PP_FIFO_SIZE * SPI_PP_SEL)) + +/* SPI Ping-Pong FIFO OP register */ +#define SPI_PP_FIFO_OP_SIZE 0x2 +#define SPI_PP_FIFO_OP_REG (SPI_PP_FIFO_BASE + 0x00) +#define SPI_PP_FIFO_OP_BYTES_SHIFT 0 +#define SPI_PP_FIFO_OP_BYTES_MASK (0x3ff << SPI_PP_FIFO_OP_BYTES_SHIFT) +#define SPI_PP_FIFO_OP_MBIT_SHIFT 11 +#define SPI_PP_FIFO_OP_MBIT_MASK (1 << SPI_PP_FIFO_OP_MBIT_SHIFT) +#define SPI_PP_FIFO_OP_CODE_SHIFT 13 +#define SPI_PP_FIFO_OP_CODE_RW (1 << SPI_PP_FIFO_OP_CODE_SHIFT) +#define SPI_PP_FIFO_OP_CODE_W (2 << SPI_PP_FIFO_OP_CODE_SHIFT) +#define SPI_PP_FIFO_OP_CODE_R (3 << SPI_PP_FIFO_OP_CODE_SHIFT) + +struct bcm63xx_hsspi_priv { + void __iomem *regs; + ulong clk_rate; + uint8_t num_cs; + uint8_t cs_pols; + uint speed; +}; + +static int bcm63xx_hsspi_cs_info(struct udevice *bus, uint cs, + struct spi_cs_info *info) +{ + struct bcm63xx_hsspi_priv *priv = dev_get_priv(bus); + + if (cs >= priv->num_cs) { + error("no cs %u\n", cs); + return -ENODEV; + } + + return 0; +} + +static int bcm63xx_hsspi_set_mode(struct udevice *bus, uint mode) +{ + struct bcm63xx_hsspi_priv *priv = dev_get_priv(bus); + + /* clock polarity */ + if (mode & SPI_CPOL) + setbits_be32(priv->regs + SPI_CTL_REG, SPI_CTL_CLK_POL_MASK); + else + clrbits_be32(priv->regs + SPI_CTL_REG, SPI_CTL_CLK_POL_MASK); + + return 0; +} + +static int bcm63xx_hsspi_set_speed(struct udevice *bus, uint speed) +{ + struct bcm63xx_hsspi_priv *priv = dev_get_priv(bus); + + priv->speed = speed; + + return 0; +} + +static void bcm63xx_hsspi_claim_cs(struct bcm63xx_hsspi_priv *priv, + struct dm_spi_slave_platdata *plat) +{ + uint32_t clr, set; + + /* profile clock */ + set = DIV_ROUND_UP(priv->clk_rate, priv->speed); + set = DIV_ROUND_UP(2048, set); + set &= SPI_PFL_CLK_FREQ_MASK; + set |= SPI_PFL_CLK_RSTLOOP_MASK; + writel_be(set, priv->regs + SPI_PFL_CLK_REG(plat->cs)); + + /* profile signal */ + set = 0; + clr = SPI_PFL_SIG_LAUNCHRIS_MASK | + SPI_PFL_SIG_LATCHRIS_MASK | + SPI_PFL_SIG_ASYNCIN_MASK; + + /* latch/launch config */ + if (plat->mode & SPI_CPHA) + set |= SPI_PFL_SIG_LAUNCHRIS_MASK; + else + set |= SPI_PFL_SIG_LATCHRIS_MASK; + + /* async clk */ + if (priv->speed > SPI_MAX_SYNC_CLOCK) + set |= SPI_PFL_SIG_ASYNCIN_MASK; + + clrsetbits_be32(priv->regs + SPI_PFL_SIG_REG(plat->cs), clr, set); + + /* global control */ + set = 0; + clr = 0; + + /* invert cs polarity */ + if (priv->cs_pols & BIT(plat->cs)) + clr |= BIT(plat->cs); + else + set |= BIT(plat->cs); + + /* invert dummy cs polarity */ + if (priv->cs_pols & BIT(!plat->cs)) + clr |= BIT(!plat->cs); + else + set |= BIT(!plat->cs); + + clrsetbits_be32(priv->regs + SPI_CTL_REG, clr, set); +} + +static void bcm63xx_hsspi_release_cs(struct bcm63xx_hsspi_priv *priv) +{ + /* restore cs polarities */ + clrsetbits_be32(priv->regs + SPI_CTL_REG, SPI_CTL_CS_POL_MASK, + priv->cs_pols); +} + +/* + * BCM63xx HSSPI driver doesn't allow keeping CS active between transfers + * because they are controlled by HW. + * 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. On the other hand it also provides a way to invert each CS + * polarity, not only between transfers like the older BCM63xx SPI driver, but + * also the rest of the time. + * + * Instead of using the prepend mechanism, this implementation inverts the + * polarity of both the desired CS and another dummy CS when the bus is + * claimed. This way, the dummy CS is restored to its inactive value when + * transfers are issued and the desired CS is preserved in its active value + * all the time. This hack is also used in the upstream linux driver and + * allows keeping CS active between trasnfers even if the HW doesn't give + * this possibility. + */ +static int bcm63xx_hsspi_xfer(struct udevice *dev, unsigned int bitlen, + const void *dout, void *din, unsigned long flags) +{ + struct bcm63xx_hsspi_priv *priv = dev_get_priv(dev->parent); + struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev); + size_t data_bytes = bitlen / 8; + size_t step_size = SPI_PP_FIFO_SIZE; + uint16_t opcode = 0; + uint32_t val; + const uint8_t *tx = dout; + uint8_t *rx = din; + + if (flags & SPI_XFER_BEGIN) + bcm63xx_hsspi_claim_cs(priv, plat); + + /* fifo operation */ + if (tx && rx) + opcode = SPI_PP_FIFO_OP_CODE_RW; + else if (rx) + opcode = SPI_PP_FIFO_OP_CODE_R; + else if (tx) + opcode = SPI_PP_FIFO_OP_CODE_W; + + if (opcode != SPI_PP_FIFO_OP_CODE_R) + step_size -= SPI_PP_FIFO_OP_SIZE; + + /* dual mode */ + if ((opcode == SPI_PP_FIFO_OP_CODE_R && plat->mode == SPI_RX_DUAL) || + (opcode == SPI_PP_FIFO_OP_CODE_W && plat->mode == SPI_TX_DUAL)) + opcode |= SPI_PP_FIFO_OP_MBIT_MASK; + + /* profile mode */ + val = SPI_PFL_MODE_FILL_MASK | + SPI_PFL_MODE_MDRDSZ_MASK | + SPI_PFL_MODE_MDWRSZ_MASK; + if (plat->mode & SPI_3WIRE) + val |= SPI_PFL_MODE_3WIRE_MASK; + writel_be(val, priv->regs + SPI_PFL_MODE_REG(plat->cs)); + + /* transfer loop */ + while (data_bytes > 0) { + size_t curr_step = min(step_size, data_bytes); + + /* copy tx data */ + if (tx) { + memcpy_toio(priv->regs + SPI_PP_FIFO_BASE + + SPI_PP_FIFO_OP_SIZE, tx, curr_step); + tx += curr_step; + } + + /* set fifo operation */ + writew_be(opcode | (curr_step & SPI_PP_FIFO_OP_BYTES_MASK), + priv->regs + SPI_PP_FIFO_OP_REG); + + /* issue the transfer */ + val = SPI_PP_CMD_OP_START; + val |= (plat->cs << SPI_PP_CMD_PFL_SHIFT) & + SPI_PP_CMD_PFL_MASK; + val |= (!plat->cs << SPI_PP_CMD_SLAVE_SHIFT) & + SPI_PP_CMD_SLAVE_MASK; + writel_be(val, priv->regs + SPI_PP_CMD_REG); + + /* wait for completion */ + do { + /* check ping-pong status */ + val = readl_be(priv->regs + SPI_PP_STAT_REG); + + /* transfer completed */ + if (!(val & SPI_PP_STAT_SRCBUSY_MASK)) + break; + } while (1); + + /* copy rx data */ + if (rx) { + memcpy_fromio(rx, priv->regs + SPI_PP_FIFO_BASE, + curr_step); + rx += curr_step; + } + + data_bytes -= curr_step; + } + + if (flags & SPI_XFER_END) + bcm63xx_hsspi_release_cs(priv); + + return 0; +} + +static const struct dm_spi_ops bcm63xx_hsspi_ops = { + .cs_info = bcm63xx_hsspi_cs_info, + .set_mode = bcm63xx_hsspi_set_mode, + .set_speed = bcm63xx_hsspi_set_speed, + .xfer = bcm63xx_hsspi_xfer, +}; + +static const struct udevice_id bcm63xx_hsspi_ids[] = { + { .compatible = "brcm,bcm6328-hsspi", }, + { /* sentinel */ } +}; + +static int bcm63xx_hsspi_child_pre_probe(struct udevice *dev) +{ + struct bcm63xx_hsspi_priv *priv = dev_get_priv(dev->parent); + 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; + } + + /* cs polarity */ + if (plat->mode & SPI_CS_HIGH) + priv->cs_pols |= BIT(plat->cs); + else + priv->cs_pols &= ~BIT(plat->cs); + + return 0; +} + +static int bcm63xx_hsspi_probe(struct udevice *dev) +{ + struct bcm63xx_hsspi_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 = devfdt_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_name(dev, "hsspi", &clk); + if (ret < 0) + return ret; + + ret = clk_enable(&clk); + if (ret < 0) + return ret; + + ret = clk_free(&clk); + if (ret < 0) + return ret; + + /* get clock rate */ + ret = clk_get_by_name(dev, "pll", &clk); + if (ret < 0) + return ret; + + priv->clk_rate = clk_get_rate(&clk); + + 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 */ + writel_be(0, priv->regs + SPI_IR_MASK_REG); + + /* clear pending interrupts */ + writel_be(SPI_IR_CLEAR_ALL, priv->regs + SPI_IR_STAT_REG); + + /* enable clk gate */ + setbits_be32(priv->regs + SPI_CTL_REG, SPI_CTL_CLK_GATE_MASK); + + /* read default cs polarities */ + priv->cs_pols = readl_be(priv->regs + SPI_CTL_REG) & + SPI_CTL_CS_POL_MASK; + + return 0; +} + +U_BOOT_DRIVER(bcm63xx_hsspi) = { + .name = "bcm63xx_hsspi", + .id = UCLASS_SPI, + .of_match = bcm63xx_hsspi_ids, + .ops = &bcm63xx_hsspi_ops, + .priv_auto_alloc_size = sizeof(struct bcm63xx_hsspi_priv), + .child_pre_probe = bcm63xx_hsspi_child_pre_probe, + .probe = bcm63xx_hsspi_probe, +};