From: Jonas Gorski Date: Sat, 30 Nov 2013 11:42:06 +0000 (+0100) Subject: spi: bcm63xx-hsspi: add bcm63xx HSSPI driver X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=142168eba9dc5c20538a67049ad53c49bc6f8336;p=linux-beck.git spi: bcm63xx-hsspi: add bcm63xx HSSPI driver Add a driver for the High Speed SPI controller found on newer BCM63XX SoCs. It does feature some new modes like 3-wire or dual spi, but neither of it is currently implemented. Signed-off-by: Jonas Gorski Signed-off-by: Mark Brown --- diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index eb1f1ef5fa2e..62ce2a9ec612 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -118,6 +118,13 @@ config SPI_BCM63XX help Enable support for the SPI controller on the Broadcom BCM63xx SoCs. +config SPI_BCM63XX_HSSPI + tristate "Broadcom BCM63XX HS SPI controller driver" + depends on BCM63XX || COMPILE_TEST + help + This enables support for the High Speed SPI controller present on + newer Broadcom BCM63XX SoCs. + config SPI_BITBANG tristate "Utilities for Bitbanging SPI masters" help diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index ab8d8644af0e..95af48d2d360 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_SPI_ATH79) += spi-ath79.o obj-$(CONFIG_SPI_AU1550) += spi-au1550.o obj-$(CONFIG_SPI_BCM2835) += spi-bcm2835.o obj-$(CONFIG_SPI_BCM63XX) += spi-bcm63xx.o +obj-$(CONFIG_SPI_BCM63XX_HSSPI) += spi-bcm63xx-hsspi.o obj-$(CONFIG_SPI_BFIN5XX) += spi-bfin5xx.o obj-$(CONFIG_SPI_BFIN_V3) += spi-bfin-v3.o obj-$(CONFIG_SPI_BFIN_SPORT) += spi-bfin-sport.o diff --git a/drivers/spi/spi-bcm63xx-hsspi.c b/drivers/spi/spi-bcm63xx-hsspi.c new file mode 100644 index 000000000000..bc8d848d33b7 --- /dev/null +++ b/drivers/spi/spi-bcm63xx-hsspi.c @@ -0,0 +1,484 @@ +/* + * Broadcom BCM63XX High Speed SPI Controller driver + * + * Copyright 2000-2010 Broadcom Corporation + * Copyright 2012-2013 Jonas Gorski + * + * Licensed under the GNU/GPL. See COPYING for details. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define HSSPI_GLOBAL_CTRL_REG 0x0 +#define GLOBAL_CTRL_CS_POLARITY_SHIFT 0 +#define GLOBAL_CTRL_CS_POLARITY_MASK 0x000000ff +#define GLOBAL_CTRL_PLL_CLK_CTRL_SHIFT 8 +#define GLOBAL_CTRL_PLL_CLK_CTRL_MASK 0x0000ff00 +#define GLOBAL_CTRL_CLK_GATE_SSOFF BIT(16) +#define GLOBAL_CTRL_CLK_POLARITY BIT(17) +#define GLOBAL_CTRL_MOSI_IDLE BIT(18) + +#define HSSPI_GLOBAL_EXT_TRIGGER_REG 0x4 + +#define HSSPI_INT_STATUS_REG 0x8 +#define HSSPI_INT_STATUS_MASKED_REG 0xc +#define HSSPI_INT_MASK_REG 0x10 + +#define HSSPI_PINGx_CMD_DONE(i) BIT((i * 8) + 0) +#define HSSPI_PINGx_RX_OVER(i) BIT((i * 8) + 1) +#define HSSPI_PINGx_TX_UNDER(i) BIT((i * 8) + 2) +#define HSSPI_PINGx_POLL_TIMEOUT(i) BIT((i * 8) + 3) +#define HSSPI_PINGx_CTRL_INVAL(i) BIT((i * 8) + 4) + +#define HSSPI_INT_CLEAR_ALL 0xff001f1f + +#define HSSPI_PINGPONG_COMMAND_REG(x) (0x80 + (x) * 0x40) +#define PINGPONG_CMD_COMMAND_MASK 0xf +#define PINGPONG_COMMAND_NOOP 0 +#define PINGPONG_COMMAND_START_NOW 1 +#define PINGPONG_COMMAND_START_TRIGGER 2 +#define PINGPONG_COMMAND_HALT 3 +#define PINGPONG_COMMAND_FLUSH 4 +#define PINGPONG_CMD_PROFILE_SHIFT 8 +#define PINGPONG_CMD_SS_SHIFT 12 + +#define HSSPI_PINGPONG_STATUS_REG(x) (0x84 + (x) * 0x40) + +#define HSSPI_PROFILE_CLK_CTRL_REG(x) (0x100 + (x) * 0x20) +#define CLK_CTRL_FREQ_CTRL_MASK 0x0000ffff +#define CLK_CTRL_SPI_CLK_2X_SEL BIT(14) +#define CLK_CTRL_ACCUM_RST_ON_LOOP BIT(15) + +#define HSSPI_PROFILE_SIGNAL_CTRL_REG(x) (0x104 + (x) * 0x20) +#define SIGNAL_CTRL_LATCH_RISING BIT(12) +#define SIGNAL_CTRL_LAUNCH_RISING BIT(13) +#define SIGNAL_CTRL_ASYNC_INPUT_PATH BIT(16) + +#define HSSPI_PROFILE_MODE_CTRL_REG(x) (0x108 + (x) * 0x20) +#define MODE_CTRL_MULTIDATA_RD_STRT_SHIFT 8 +#define MODE_CTRL_MULTIDATA_WR_STRT_SHIFT 12 +#define MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT 16 +#define MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT 18 +#define MODE_CTRL_MODE_3WIRE BIT(20) +#define MODE_CTRL_PREPENDBYTE_CNT_SHIFT 24 + +#define HSSPI_FIFO_REG(x) (0x200 + (x) * 0x200) + + +#define HSSPI_OP_CODE_SHIFT 13 +#define HSSPI_OP_SLEEP (0 << HSSPI_OP_CODE_SHIFT) +#define HSSPI_OP_READ_WRITE (1 << HSSPI_OP_CODE_SHIFT) +#define HSSPI_OP_WRITE (2 << HSSPI_OP_CODE_SHIFT) +#define HSSPI_OP_READ (3 << HSSPI_OP_CODE_SHIFT) +#define HSSPI_OP_SETIRQ (4 << HSSPI_OP_CODE_SHIFT) + +#define HSSPI_BUFFER_LEN 512 +#define HSSPI_OPCODE_LEN 2 + +#define HSSPI_MAX_PREPEND_LEN 15 + +#define HSSPI_MAX_SYNC_CLOCK 30000000 + +#define HSSPI_BUS_NUM 1 /* 0 is legacy SPI */ + +struct bcm63xx_hsspi { + struct completion done; + struct mutex bus_mutex; + + struct platform_device *pdev; + struct clk *clk; + void __iomem *regs; + u8 __iomem *fifo; + + u32 speed_hz; + u8 cs_polarity; +}; + +static void bcm63xx_hsspi_set_cs(struct bcm63xx_hsspi *bs, unsigned cs, + bool active) +{ + u32 reg; + + mutex_lock(&bs->bus_mutex); + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG); + + reg &= ~BIT(cs); + if (active == !(bs->cs_polarity & BIT(cs))) + reg |= BIT(cs); + + __raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG); + mutex_unlock(&bs->bus_mutex); +} + +static void bcm63xx_hsspi_set_clk(struct bcm63xx_hsspi *bs, + struct spi_device *spi, int hz) +{ + unsigned profile = spi->chip_select; + u32 reg; + + reg = DIV_ROUND_UP(2048, DIV_ROUND_UP(bs->speed_hz, hz)); + __raw_writel(CLK_CTRL_ACCUM_RST_ON_LOOP | reg, + bs->regs + HSSPI_PROFILE_CLK_CTRL_REG(profile)); + + reg = __raw_readl(bs->regs + HSSPI_PROFILE_SIGNAL_CTRL_REG(profile)); + if (hz > HSSPI_MAX_SYNC_CLOCK) + reg |= SIGNAL_CTRL_ASYNC_INPUT_PATH; + else + reg &= ~SIGNAL_CTRL_ASYNC_INPUT_PATH; + __raw_writel(reg, bs->regs + HSSPI_PROFILE_SIGNAL_CTRL_REG(profile)); + + mutex_lock(&bs->bus_mutex); + /* setup clock polarity */ + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG); + reg &= ~GLOBAL_CTRL_CLK_POLARITY; + if (spi->mode & SPI_CPOL) + reg |= GLOBAL_CTRL_CLK_POLARITY; + __raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG); + mutex_unlock(&bs->bus_mutex); +} + +static int bcm63xx_hsspi_do_txrx(struct spi_device *spi, struct spi_transfer *t) +{ + struct bcm63xx_hsspi *bs = spi_master_get_devdata(spi->master); + unsigned chip_select = spi->chip_select; + u16 opcode = 0; + int pending = t->len; + int step_size = HSSPI_BUFFER_LEN; + const u8 *tx = t->tx_buf; + u8 *rx = t->rx_buf; + + bcm63xx_hsspi_set_clk(bs, spi, t->speed_hz); + bcm63xx_hsspi_set_cs(bs, spi->chip_select, true); + + if (tx && rx) + opcode = HSSPI_OP_READ_WRITE; + else if (tx) + opcode = HSSPI_OP_WRITE; + else if (rx) + opcode = HSSPI_OP_READ; + + if (opcode != HSSPI_OP_READ) + step_size -= HSSPI_OPCODE_LEN; + + __raw_writel(0 << MODE_CTRL_PREPENDBYTE_CNT_SHIFT | + 2 << MODE_CTRL_MULTIDATA_WR_STRT_SHIFT | + 2 << MODE_CTRL_MULTIDATA_RD_STRT_SHIFT | 0xff, + bs->regs + HSSPI_PROFILE_MODE_CTRL_REG(chip_select)); + + while (pending > 0) { + int curr_step = min_t(int, step_size, pending); + + init_completion(&bs->done); + if (tx) { + memcpy_toio(bs->fifo + HSSPI_OPCODE_LEN, tx, curr_step); + tx += curr_step; + } + + __raw_writew(opcode | curr_step, bs->fifo); + + /* enable interrupt */ + __raw_writel(HSSPI_PINGx_CMD_DONE(0), + bs->regs + HSSPI_INT_MASK_REG); + + /* start the transfer */ + __raw_writel(!chip_select << PINGPONG_CMD_SS_SHIFT | + chip_select << PINGPONG_CMD_PROFILE_SHIFT | + PINGPONG_COMMAND_START_NOW, + bs->regs + HSSPI_PINGPONG_COMMAND_REG(0)); + + if (wait_for_completion_timeout(&bs->done, HZ) == 0) { + dev_err(&bs->pdev->dev, "transfer timed out!\n"); + return -ETIMEDOUT; + } + + if (rx) { + memcpy_fromio(rx, bs->fifo, curr_step); + rx += curr_step; + } + + pending -= curr_step; + } + + return 0; +} + +static int bcm63xx_hsspi_setup(struct spi_device *spi) +{ + struct bcm63xx_hsspi *bs = spi_master_get_devdata(spi->master); + u32 reg; + + reg = __raw_readl(bs->regs + + HSSPI_PROFILE_SIGNAL_CTRL_REG(spi->chip_select)); + reg &= ~(SIGNAL_CTRL_LAUNCH_RISING | SIGNAL_CTRL_LATCH_RISING); + if (spi->mode & SPI_CPHA) + reg |= SIGNAL_CTRL_LAUNCH_RISING; + else + reg |= SIGNAL_CTRL_LATCH_RISING; + __raw_writel(reg, bs->regs + + HSSPI_PROFILE_SIGNAL_CTRL_REG(spi->chip_select)); + + mutex_lock(&bs->bus_mutex); + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG); + + /* only change actual polarities if there is no transfer */ + if ((reg & GLOBAL_CTRL_CS_POLARITY_MASK) == bs->cs_polarity) { + if (spi->mode & SPI_CS_HIGH) + reg |= BIT(spi->chip_select); + else + reg &= ~BIT(spi->chip_select); + __raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG); + } + + if (spi->mode & SPI_CS_HIGH) + bs->cs_polarity |= BIT(spi->chip_select); + else + bs->cs_polarity &= ~BIT(spi->chip_select); + + mutex_unlock(&bs->bus_mutex); + + return 0; +} + +static int bcm63xx_hsspi_transfer_one(struct spi_master *master, + struct spi_message *msg) +{ + struct bcm63xx_hsspi *bs = spi_master_get_devdata(master); + struct spi_transfer *t; + struct spi_device *spi = msg->spi; + int status = -EINVAL; + int dummy_cs; + u32 reg; + + /* This controller does not support keeping CS active during idle. + * To work around this, we use the following ugly hack: + * + * a. Invert the target chip select's polarity so it will be active. + * b. Select a "dummy" chip select to use as the hardware target. + * c. Invert the dummy chip select's polarity so it will be inactive + * during the actual transfers. + * d. Tell the hardware to send to the dummy chip select. Thanks to + * the multiplexed nature of SPI the actual target will receive + * the transfer and we see its response. + * + * e. At the end restore the polarities again to their default values. + */ + + dummy_cs = !spi->chip_select; + bcm63xx_hsspi_set_cs(bs, dummy_cs, true); + + list_for_each_entry(t, &msg->transfers, transfer_list) { + status = bcm63xx_hsspi_do_txrx(spi, t); + if (status) + break; + + msg->actual_length += t->len; + + if (t->delay_usecs) + udelay(t->delay_usecs); + + if (t->cs_change) + bcm63xx_hsspi_set_cs(bs, spi->chip_select, false); + } + + mutex_lock(&bs->bus_mutex); + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG); + reg &= ~GLOBAL_CTRL_CS_POLARITY_MASK; + reg |= bs->cs_polarity; + __raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG); + mutex_unlock(&bs->bus_mutex); + + msg->status = status; + spi_finalize_current_message(master); + + return 0; +} + +static irqreturn_t bcm63xx_hsspi_interrupt(int irq, void *dev_id) +{ + struct bcm63xx_hsspi *bs = (struct bcm63xx_hsspi *)dev_id; + + if (__raw_readl(bs->regs + HSSPI_INT_STATUS_MASKED_REG) == 0) + return IRQ_NONE; + + __raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG); + __raw_writel(0, bs->regs + HSSPI_INT_MASK_REG); + + complete(&bs->done); + + return IRQ_HANDLED; +} + +static int bcm63xx_hsspi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct bcm63xx_hsspi *bs; + struct resource *res_mem; + void __iomem *regs; + struct device *dev = &pdev->dev; + struct clk *clk; + int irq, ret; + u32 reg, rate; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(dev, "no irq\n"); + return -ENXIO; + } + + res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + regs = devm_request_and_ioremap(dev, res_mem); + if (IS_ERR(regs)) + return PTR_ERR(regs); + + clk = clk_get(dev, "hsspi"); + + if (IS_ERR(clk)) + return PTR_ERR(clk); + + rate = clk_get_rate(clk); + if (!rate) { + ret = -EINVAL; + goto out_put_clk; + } + + clk_prepare_enable(clk); + + master = spi_alloc_master(&pdev->dev, sizeof(*bs)); + if (!master) { + ret = -ENOMEM; + goto out_disable_clk; + } + + bs = spi_master_get_devdata(master); + bs->pdev = pdev; + bs->clk = clk; + bs->regs = regs; + bs->speed_hz = rate; + bs->fifo = (u8 __iomem *)(bs->regs + HSSPI_FIFO_REG(0)); + + mutex_init(&bs->bus_mutex); + + master->bus_num = HSSPI_BUS_NUM; + master->num_chipselect = 8; + master->setup = bcm63xx_hsspi_setup; + master->transfer_one_message = bcm63xx_hsspi_transfer_one; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->bits_per_word_mask = SPI_BPW_MASK(8); + master->auto_runtime_pm = true; + + platform_set_drvdata(pdev, master); + + /* Initialize the hardware */ + __raw_writel(0, bs->regs + HSSPI_INT_MASK_REG); + + /* clean up any pending interrupts */ + __raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG); + + /* read out default CS polarities */ + reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG); + bs->cs_polarity = reg & GLOBAL_CTRL_CS_POLARITY_MASK; + __raw_writel(reg | GLOBAL_CTRL_CLK_GATE_SSOFF, + bs->regs + HSSPI_GLOBAL_CTRL_REG); + + ret = devm_request_irq(dev, irq, bcm63xx_hsspi_interrupt, IRQF_SHARED, + pdev->name, bs); + + if (ret) + goto out_put_master; + + /* register and we are done */ + ret = spi_register_master(master); + if (ret) + goto out_put_master; + + return 0; + +out_put_master: + spi_master_put(master); +out_disable_clk: + clk_disable_unprepare(clk); +out_put_clk: + clk_put(clk); + + return ret; +} + + +static int bcm63xx_hsspi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct bcm63xx_hsspi *bs = spi_master_get_devdata(master); + + spi_unregister_master(master); + + /* reset the hardware and block queue progress */ + __raw_writel(0, bs->regs + HSSPI_INT_MASK_REG); + clk_disable_unprepare(bs->clk); + clk_put(bs->clk); + + return 0; +} + +#ifdef CONFIG_PM +static int bcm63xx_hsspi_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct bcm63xx_hsspi *bs = spi_master_get_devdata(master); + + spi_master_suspend(master); + clk_disable(bs->clk); + + return 0; +} + +static int bcm63xx_hsspi_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct bcm63xx_hsspi *bs = spi_master_get_devdata(master); + + clk_enable(bs->clk); + spi_master_resume(master); + + return 0; +} + +static const struct dev_pm_ops bcm63xx_hsspi_pm_ops = { + .suspend = bcm63xx_hsspi_suspend, + .resume = bcm63xx_hsspi_resume, +}; + +#define BCM63XX_HSSPI_PM_OPS (&bcm63xx_hsspi_pm_ops) +#else +#define BCM63XX_HSSPI_PM_OPS NULL +#endif + + + +static struct platform_driver bcm63xx_hsspi_driver = { + .driver = { + .name = "bcm63xx-hsspi", + .owner = THIS_MODULE, + .pm = BCM63XX_HSSPI_PM_OPS, + }, + .probe = bcm63xx_hsspi_probe, + .remove = bcm63xx_hsspi_remove, +}; + +module_platform_driver(bcm63xx_hsspi_driver); + +MODULE_ALIAS("platform:bcm63xx_hsspi"); +MODULE_DESCRIPTION("Broadcom BCM63xx High Speed SPI Controller driver"); +MODULE_AUTHOR("Jonas Gorski "); +MODULE_LICENSE("GPL");