From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/drivers/spi/spi-orion.c | 572 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 572 insertions(+) create mode 100644 kernel/drivers/spi/spi-orion.c (limited to 'kernel/drivers/spi/spi-orion.c') diff --git a/kernel/drivers/spi/spi-orion.c b/kernel/drivers/spi/spi-orion.c new file mode 100644 index 000000000..ff97cabda --- /dev/null +++ b/kernel/drivers/spi/spi-orion.c @@ -0,0 +1,572 @@ +/* + * Marvell Orion SPI controller driver + * + * Author: Shadi Ammouri + * Copyright (C) 2007-2008 Marvell Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRIVER_NAME "orion_spi" + +/* Runtime PM autosuspend timeout: PM is fairly light on this driver */ +#define SPI_AUTOSUSPEND_TIMEOUT 200 + +/* Some SoCs using this driver support up to 8 chip selects. + * It is up to the implementer to only use the chip selects + * that are available. + */ +#define ORION_NUM_CHIPSELECTS 8 + +#define ORION_SPI_WAIT_RDY_MAX_LOOP 2000 /* in usec */ + +#define ORION_SPI_IF_CTRL_REG 0x00 +#define ORION_SPI_IF_CONFIG_REG 0x04 +#define ORION_SPI_DATA_OUT_REG 0x08 +#define ORION_SPI_DATA_IN_REG 0x0c +#define ORION_SPI_INT_CAUSE_REG 0x10 + +#define ORION_SPI_MODE_CPOL (1 << 11) +#define ORION_SPI_MODE_CPHA (1 << 12) +#define ORION_SPI_IF_8_16_BIT_MODE (1 << 5) +#define ORION_SPI_CLK_PRESCALE_MASK 0x1F +#define ARMADA_SPI_CLK_PRESCALE_MASK 0xDF +#define ORION_SPI_MODE_MASK (ORION_SPI_MODE_CPOL | \ + ORION_SPI_MODE_CPHA) +#define ORION_SPI_CS_MASK 0x1C +#define ORION_SPI_CS_SHIFT 2 +#define ORION_SPI_CS(cs) ((cs << ORION_SPI_CS_SHIFT) & \ + ORION_SPI_CS_MASK) + +enum orion_spi_type { + ORION_SPI, + ARMADA_SPI, +}; + +struct orion_spi_dev { + enum orion_spi_type typ; + /* + * min_divisor and max_hz should be exclusive, the only we can + * have both is for managing the armada-370-spi case with old + * device tree + */ + unsigned long max_hz; + unsigned int min_divisor; + unsigned int max_divisor; + u32 prescale_mask; +}; + +struct orion_spi { + struct spi_master *master; + void __iomem *base; + struct clk *clk; + const struct orion_spi_dev *devdata; +}; + +static inline void __iomem *spi_reg(struct orion_spi *orion_spi, u32 reg) +{ + return orion_spi->base + reg; +} + +static inline void +orion_spi_setbits(struct orion_spi *orion_spi, u32 reg, u32 mask) +{ + void __iomem *reg_addr = spi_reg(orion_spi, reg); + u32 val; + + val = readl(reg_addr); + val |= mask; + writel(val, reg_addr); +} + +static inline void +orion_spi_clrbits(struct orion_spi *orion_spi, u32 reg, u32 mask) +{ + void __iomem *reg_addr = spi_reg(orion_spi, reg); + u32 val; + + val = readl(reg_addr); + val &= ~mask; + writel(val, reg_addr); +} + +static int orion_spi_baudrate_set(struct spi_device *spi, unsigned int speed) +{ + u32 tclk_hz; + u32 rate; + u32 prescale; + u32 reg; + struct orion_spi *orion_spi; + const struct orion_spi_dev *devdata; + + orion_spi = spi_master_get_devdata(spi->master); + devdata = orion_spi->devdata; + + tclk_hz = clk_get_rate(orion_spi->clk); + + if (devdata->typ == ARMADA_SPI) { + unsigned int clk, spr, sppr, sppr2, err; + unsigned int best_spr, best_sppr, best_err; + + best_err = speed; + best_spr = 0; + best_sppr = 0; + + /* Iterate over the valid range looking for best fit */ + for (sppr = 0; sppr < 8; sppr++) { + sppr2 = 0x1 << sppr; + + spr = tclk_hz / sppr2; + spr = DIV_ROUND_UP(spr, speed); + if ((spr == 0) || (spr > 15)) + continue; + + clk = tclk_hz / (spr * sppr2); + err = speed - clk; + + if (err < best_err) { + best_spr = spr; + best_sppr = sppr; + best_err = err; + } + } + + if ((best_sppr == 0) && (best_spr == 0)) + return -EINVAL; + + prescale = ((best_sppr & 0x6) << 5) | + ((best_sppr & 0x1) << 4) | best_spr; + } else { + /* + * the supported rates are: 4,6,8...30 + * round up as we look for equal or less speed + */ + rate = DIV_ROUND_UP(tclk_hz, speed); + rate = roundup(rate, 2); + + /* check if requested speed is too small */ + if (rate > 30) + return -EINVAL; + + if (rate < 4) + rate = 4; + + /* Convert the rate to SPI clock divisor value. */ + prescale = 0x10 + rate/2; + } + + reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG)); + reg = ((reg & ~devdata->prescale_mask) | prescale); + writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG)); + + return 0; +} + +static void +orion_spi_mode_set(struct spi_device *spi) +{ + u32 reg; + struct orion_spi *orion_spi; + + orion_spi = spi_master_get_devdata(spi->master); + + reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG)); + reg &= ~ORION_SPI_MODE_MASK; + if (spi->mode & SPI_CPOL) + reg |= ORION_SPI_MODE_CPOL; + if (spi->mode & SPI_CPHA) + reg |= ORION_SPI_MODE_CPHA; + writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG)); +} + +/* + * called only when no transfer is active on the bus + */ +static int +orion_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) +{ + struct orion_spi *orion_spi; + unsigned int speed = spi->max_speed_hz; + unsigned int bits_per_word = spi->bits_per_word; + int rc; + + orion_spi = spi_master_get_devdata(spi->master); + + if ((t != NULL) && t->speed_hz) + speed = t->speed_hz; + + if ((t != NULL) && t->bits_per_word) + bits_per_word = t->bits_per_word; + + orion_spi_mode_set(spi); + + rc = orion_spi_baudrate_set(spi, speed); + if (rc) + return rc; + + if (bits_per_word == 16) + orion_spi_setbits(orion_spi, ORION_SPI_IF_CONFIG_REG, + ORION_SPI_IF_8_16_BIT_MODE); + else + orion_spi_clrbits(orion_spi, ORION_SPI_IF_CONFIG_REG, + ORION_SPI_IF_8_16_BIT_MODE); + + return 0; +} + +static void orion_spi_set_cs(struct spi_device *spi, bool enable) +{ + struct orion_spi *orion_spi; + + orion_spi = spi_master_get_devdata(spi->master); + + orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, ORION_SPI_CS_MASK); + orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG, + ORION_SPI_CS(spi->chip_select)); + + /* Chip select logic is inverted from spi_set_cs */ + if (!enable) + orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1); + else + orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1); +} + +static inline int orion_spi_wait_till_ready(struct orion_spi *orion_spi) +{ + int i; + + for (i = 0; i < ORION_SPI_WAIT_RDY_MAX_LOOP; i++) { + if (readl(spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG))) + return 1; + + udelay(1); + } + + return -1; +} + +static inline int +orion_spi_write_read_8bit(struct spi_device *spi, + const u8 **tx_buf, u8 **rx_buf) +{ + void __iomem *tx_reg, *rx_reg, *int_reg; + struct orion_spi *orion_spi; + + orion_spi = spi_master_get_devdata(spi->master); + tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG); + rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG); + int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG); + + /* clear the interrupt cause register */ + writel(0x0, int_reg); + + if (tx_buf && *tx_buf) + writel(*(*tx_buf)++, tx_reg); + else + writel(0, tx_reg); + + if (orion_spi_wait_till_ready(orion_spi) < 0) { + dev_err(&spi->dev, "TXS timed out\n"); + return -1; + } + + if (rx_buf && *rx_buf) + *(*rx_buf)++ = readl(rx_reg); + + return 1; +} + +static inline int +orion_spi_write_read_16bit(struct spi_device *spi, + const u16 **tx_buf, u16 **rx_buf) +{ + void __iomem *tx_reg, *rx_reg, *int_reg; + struct orion_spi *orion_spi; + + orion_spi = spi_master_get_devdata(spi->master); + tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG); + rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG); + int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG); + + /* clear the interrupt cause register */ + writel(0x0, int_reg); + + if (tx_buf && *tx_buf) + writel(__cpu_to_le16(get_unaligned((*tx_buf)++)), tx_reg); + else + writel(0, tx_reg); + + if (orion_spi_wait_till_ready(orion_spi) < 0) { + dev_err(&spi->dev, "TXS timed out\n"); + return -1; + } + + if (rx_buf && *rx_buf) + put_unaligned(__le16_to_cpu(readl(rx_reg)), (*rx_buf)++); + + return 1; +} + +static unsigned int +orion_spi_write_read(struct spi_device *spi, struct spi_transfer *xfer) +{ + unsigned int count; + int word_len; + + word_len = spi->bits_per_word; + count = xfer->len; + + if (word_len == 8) { + const u8 *tx = xfer->tx_buf; + u8 *rx = xfer->rx_buf; + + do { + if (orion_spi_write_read_8bit(spi, &tx, &rx) < 0) + goto out; + count--; + } while (count); + } else if (word_len == 16) { + const u16 *tx = xfer->tx_buf; + u16 *rx = xfer->rx_buf; + + do { + if (orion_spi_write_read_16bit(spi, &tx, &rx) < 0) + goto out; + count -= 2; + } while (count); + } + +out: + return xfer->len - count; +} + +static int orion_spi_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *t) +{ + int status = 0; + + status = orion_spi_setup_transfer(spi, t); + if (status < 0) + return status; + + if (t->len) + orion_spi_write_read(spi, t); + + return status; +} + +static int orion_spi_setup(struct spi_device *spi) +{ + return orion_spi_setup_transfer(spi, NULL); +} + +static int orion_spi_reset(struct orion_spi *orion_spi) +{ + /* Verify that the CS is deasserted */ + orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1); + return 0; +} + +static const struct orion_spi_dev orion_spi_dev_data = { + .typ = ORION_SPI, + .min_divisor = 4, + .max_divisor = 30, + .prescale_mask = ORION_SPI_CLK_PRESCALE_MASK, +}; + +static const struct orion_spi_dev armada_spi_dev_data = { + .typ = ARMADA_SPI, + .min_divisor = 4, + .max_divisor = 1920, + .max_hz = 50000000, + .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK, +}; + +static const struct of_device_id orion_spi_of_match_table[] = { + { .compatible = "marvell,orion-spi", .data = &orion_spi_dev_data, }, + { .compatible = "marvell,armada-370-spi", .data = &armada_spi_dev_data, }, + {} +}; +MODULE_DEVICE_TABLE(of, orion_spi_of_match_table); + +static int orion_spi_probe(struct platform_device *pdev) +{ + const struct of_device_id *of_id; + const struct orion_spi_dev *devdata; + struct spi_master *master; + struct orion_spi *spi; + struct resource *r; + unsigned long tclk_hz; + int status = 0; + + master = spi_alloc_master(&pdev->dev, sizeof(*spi)); + if (master == NULL) { + dev_dbg(&pdev->dev, "master allocation failed\n"); + return -ENOMEM; + } + + if (pdev->id != -1) + master->bus_num = pdev->id; + if (pdev->dev.of_node) { + u32 cell_index; + + if (!of_property_read_u32(pdev->dev.of_node, "cell-index", + &cell_index)) + master->bus_num = cell_index; + } + + /* we support only mode 0, and no options */ + master->mode_bits = SPI_CPHA | SPI_CPOL; + master->set_cs = orion_spi_set_cs; + master->transfer_one = orion_spi_transfer_one; + master->num_chipselect = ORION_NUM_CHIPSELECTS; + master->setup = orion_spi_setup; + master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16); + master->auto_runtime_pm = true; + + platform_set_drvdata(pdev, master); + + spi = spi_master_get_devdata(master); + spi->master = master; + + of_id = of_match_device(orion_spi_of_match_table, &pdev->dev); + devdata = (of_id) ? of_id->data : &orion_spi_dev_data; + spi->devdata = devdata; + + spi->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(spi->clk)) { + status = PTR_ERR(spi->clk); + goto out; + } + + status = clk_prepare_enable(spi->clk); + if (status) + goto out; + + tclk_hz = clk_get_rate(spi->clk); + + /* + * With old device tree, armada-370-spi could be used with + * Armada XP, however for this SoC the maximum frequency is + * 50MHz instead of tclk/4. On Armada 370, tclk cannot be + * higher than 200MHz. So, in order to be able to handle both + * SoCs, we can take the minimum of 50MHz and tclk/4. + */ + if (of_device_is_compatible(pdev->dev.of_node, + "marvell,armada-370-spi")) + master->max_speed_hz = min(devdata->max_hz, + DIV_ROUND_UP(tclk_hz, devdata->min_divisor)); + else + master->max_speed_hz = + DIV_ROUND_UP(tclk_hz, devdata->min_divisor); + master->min_speed_hz = DIV_ROUND_UP(tclk_hz, devdata->max_divisor); + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + spi->base = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(spi->base)) { + status = PTR_ERR(spi->base); + goto out_rel_clk; + } + + pm_runtime_set_active(&pdev->dev); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT); + pm_runtime_enable(&pdev->dev); + + status = orion_spi_reset(spi); + if (status < 0) + goto out_rel_pm; + + pm_runtime_mark_last_busy(&pdev->dev); + pm_runtime_put_autosuspend(&pdev->dev); + + master->dev.of_node = pdev->dev.of_node; + status = spi_register_master(master); + if (status < 0) + goto out_rel_pm; + + return status; + +out_rel_pm: + pm_runtime_disable(&pdev->dev); +out_rel_clk: + clk_disable_unprepare(spi->clk); +out: + spi_master_put(master); + return status; +} + + +static int orion_spi_remove(struct platform_device *pdev) +{ + struct spi_master *master = platform_get_drvdata(pdev); + struct orion_spi *spi = spi_master_get_devdata(master); + + pm_runtime_get_sync(&pdev->dev); + clk_disable_unprepare(spi->clk); + + spi_unregister_master(master); + pm_runtime_disable(&pdev->dev); + + return 0; +} + +MODULE_ALIAS("platform:" DRIVER_NAME); + +#ifdef CONFIG_PM +static int orion_spi_runtime_suspend(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct orion_spi *spi = spi_master_get_devdata(master); + + clk_disable_unprepare(spi->clk); + return 0; +} + +static int orion_spi_runtime_resume(struct device *dev) +{ + struct spi_master *master = dev_get_drvdata(dev); + struct orion_spi *spi = spi_master_get_devdata(master); + + return clk_prepare_enable(spi->clk); +} +#endif + +static const struct dev_pm_ops orion_spi_pm_ops = { + SET_RUNTIME_PM_OPS(orion_spi_runtime_suspend, + orion_spi_runtime_resume, + NULL) +}; + +static struct platform_driver orion_spi_driver = { + .driver = { + .name = DRIVER_NAME, + .pm = &orion_spi_pm_ops, + .of_match_table = of_match_ptr(orion_spi_of_match_table), + }, + .probe = orion_spi_probe, + .remove = orion_spi_remove, +}; + +module_platform_driver(orion_spi_driver); + +MODULE_DESCRIPTION("Orion SPI driver"); +MODULE_AUTHOR("Shadi Ammouri "); +MODULE_LICENSE("GPL"); -- cgit 1.2.3-korg