diff options
Diffstat (limited to 'drivers/ata/sata_gemini.c')
| -rw-r--r-- | drivers/ata/sata_gemini.c | 434 |
1 files changed, 434 insertions, 0 deletions
diff --git a/drivers/ata/sata_gemini.c b/drivers/ata/sata_gemini.c new file mode 100644 index 000000000..c96fcf9ee --- /dev/null +++ b/drivers/ata/sata_gemini.c @@ -0,0 +1,434 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Cortina Systems Gemini SATA bridge add-on to Faraday FTIDE010 + * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org> + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/bitops.h> +#include <linux/mfd/syscon.h> +#include <linux/regmap.h> +#include <linux/delay.h> +#include <linux/reset.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/pinctrl/consumer.h> +#include "sata_gemini.h" + +#define DRV_NAME "gemini_sata_bridge" + +/** + * struct sata_gemini - a state container for a Gemini SATA bridge + * @dev: the containing device + * @base: remapped I/O memory base + * @muxmode: the current muxing mode + * @ide_pins: if the device is using the plain IDE interface pins + * @sata_bridge: if the device enables the SATA bridge + * @sata0_reset: SATA0 reset handler + * @sata1_reset: SATA1 reset handler + * @sata0_pclk: SATA0 PCLK handler + * @sata1_pclk: SATA1 PCLK handler + */ +struct sata_gemini { + struct device *dev; + void __iomem *base; + enum gemini_muxmode muxmode; + bool ide_pins; + bool sata_bridge; + struct reset_control *sata0_reset; + struct reset_control *sata1_reset; + struct clk *sata0_pclk; + struct clk *sata1_pclk; +}; + +/* Miscellaneous Control Register */ +#define GEMINI_GLOBAL_MISC_CTRL 0x30 +/* + * Values of IDE IOMUX bits in the misc control register + * + * Bits 26:24 are "IDE IO Select", which decides what SATA + * adapters are connected to which of the two IDE/ATA + * controllers in the Gemini. We can connect the two IDE blocks + * to one SATA adapter each, both acting as master, or one IDE + * blocks to two SATA adapters so the IDE block can act in a + * master/slave configuration. + * + * We also bring out different blocks on the actual IDE + * pins (not SATA pins) if (and only if) these are muxed in. + * + * 111-100 - Reserved + * Mode 0: 000 - ata0 master <-> sata0 + * ata1 master <-> sata1 + * ata0 slave interface brought out on IDE pads + * Mode 1: 001 - ata0 master <-> sata0 + * ata1 master <-> sata1 + * ata1 slave interface brought out on IDE pads + * Mode 2: 010 - ata1 master <-> sata1 + * ata1 slave <-> sata0 + * ata0 master and slave interfaces brought out + * on IDE pads + * Mode 3: 011 - ata0 master <-> sata0 + * ata1 slave <-> sata1 + * ata1 master and slave interfaces brought out + * on IDE pads + */ +#define GEMINI_IDE_IOMUX_MASK (7 << 24) +#define GEMINI_IDE_IOMUX_MODE0 (0 << 24) +#define GEMINI_IDE_IOMUX_MODE1 (1 << 24) +#define GEMINI_IDE_IOMUX_MODE2 (2 << 24) +#define GEMINI_IDE_IOMUX_MODE3 (3 << 24) +#define GEMINI_IDE_IOMUX_SHIFT (24) + +/* + * Registers directly controlling the PATA<->SATA adapters + */ +#define GEMINI_SATA_ID 0x00 +#define GEMINI_SATA_PHY_ID 0x04 +#define GEMINI_SATA0_STATUS 0x08 +#define GEMINI_SATA1_STATUS 0x0c +#define GEMINI_SATA0_CTRL 0x18 +#define GEMINI_SATA1_CTRL 0x1c + +#define GEMINI_SATA_STATUS_BIST_DONE BIT(5) +#define GEMINI_SATA_STATUS_BIST_OK BIT(4) +#define GEMINI_SATA_STATUS_PHY_READY BIT(0) + +#define GEMINI_SATA_CTRL_PHY_BIST_EN BIT(14) +#define GEMINI_SATA_CTRL_PHY_FORCE_IDLE BIT(13) +#define GEMINI_SATA_CTRL_PHY_FORCE_READY BIT(12) +#define GEMINI_SATA_CTRL_PHY_AFE_LOOP_EN BIT(10) +#define GEMINI_SATA_CTRL_PHY_DIG_LOOP_EN BIT(9) +#define GEMINI_SATA_CTRL_HOTPLUG_DETECT_EN BIT(4) +#define GEMINI_SATA_CTRL_ATAPI_EN BIT(3) +#define GEMINI_SATA_CTRL_BUS_WITH_20 BIT(2) +#define GEMINI_SATA_CTRL_SLAVE_EN BIT(1) +#define GEMINI_SATA_CTRL_EN BIT(0) + +/* + * There is only ever one instance of this bridge on a system, + * so create a singleton so that the FTIDE010 instances can grab + * a reference to it. + */ +static struct sata_gemini *sg_singleton; + +struct sata_gemini *gemini_sata_bridge_get(void) +{ + if (sg_singleton) + return sg_singleton; + return ERR_PTR(-EPROBE_DEFER); +} +EXPORT_SYMBOL(gemini_sata_bridge_get); + +bool gemini_sata_bridge_enabled(struct sata_gemini *sg, bool is_ata1) +{ + if (!sg->sata_bridge) + return false; + /* + * In muxmode 2 and 3 one of the ATA controllers is + * actually not connected to any SATA bridge. + */ + if ((sg->muxmode == GEMINI_MUXMODE_2) && + !is_ata1) + return false; + if ((sg->muxmode == GEMINI_MUXMODE_3) && + is_ata1) + return false; + + return true; +} +EXPORT_SYMBOL(gemini_sata_bridge_enabled); + +enum gemini_muxmode gemini_sata_get_muxmode(struct sata_gemini *sg) +{ + return sg->muxmode; +} +EXPORT_SYMBOL(gemini_sata_get_muxmode); + +static int gemini_sata_setup_bridge(struct sata_gemini *sg, + unsigned int bridge) +{ + unsigned long timeout = jiffies + (HZ * 1); + bool bridge_online; + u32 val; + + if (bridge == 0) { + val = GEMINI_SATA_CTRL_HOTPLUG_DETECT_EN | GEMINI_SATA_CTRL_EN; + /* SATA0 slave mode is only used in muxmode 2 */ + if (sg->muxmode == GEMINI_MUXMODE_2) + val |= GEMINI_SATA_CTRL_SLAVE_EN; + writel(val, sg->base + GEMINI_SATA0_CTRL); + } else { + val = GEMINI_SATA_CTRL_HOTPLUG_DETECT_EN | GEMINI_SATA_CTRL_EN; + /* SATA1 slave mode is only used in muxmode 3 */ + if (sg->muxmode == GEMINI_MUXMODE_3) + val |= GEMINI_SATA_CTRL_SLAVE_EN; + writel(val, sg->base + GEMINI_SATA1_CTRL); + } + + /* Vendor code waits 10 ms here */ + msleep(10); + + /* Wait for PHY to become ready */ + do { + msleep(100); + + if (bridge == 0) + val = readl(sg->base + GEMINI_SATA0_STATUS); + else + val = readl(sg->base + GEMINI_SATA1_STATUS); + if (val & GEMINI_SATA_STATUS_PHY_READY) + break; + } while (time_before(jiffies, timeout)); + + bridge_online = !!(val & GEMINI_SATA_STATUS_PHY_READY); + + dev_info(sg->dev, "SATA%d PHY %s\n", bridge, + bridge_online ? "ready" : "not ready"); + + return bridge_online ? 0: -ENODEV; +} + +int gemini_sata_start_bridge(struct sata_gemini *sg, unsigned int bridge) +{ + struct clk *pclk; + int ret; + + if (bridge == 0) + pclk = sg->sata0_pclk; + else + pclk = sg->sata1_pclk; + clk_enable(pclk); + msleep(10); + + /* Do not keep clocking a bridge that is not online */ + ret = gemini_sata_setup_bridge(sg, bridge); + if (ret) + clk_disable(pclk); + + return ret; +} +EXPORT_SYMBOL(gemini_sata_start_bridge); + +void gemini_sata_stop_bridge(struct sata_gemini *sg, unsigned int bridge) +{ + if (bridge == 0) + clk_disable(sg->sata0_pclk); + else if (bridge == 1) + clk_disable(sg->sata1_pclk); +} +EXPORT_SYMBOL(gemini_sata_stop_bridge); + +int gemini_sata_reset_bridge(struct sata_gemini *sg, + unsigned int bridge) +{ + if (bridge == 0) + reset_control_reset(sg->sata0_reset); + else + reset_control_reset(sg->sata1_reset); + msleep(10); + return gemini_sata_setup_bridge(sg, bridge); +} +EXPORT_SYMBOL(gemini_sata_reset_bridge); + +static int gemini_sata_bridge_init(struct sata_gemini *sg) +{ + struct device *dev = sg->dev; + u32 sata_id, sata_phy_id; + int ret; + + sg->sata0_pclk = devm_clk_get(dev, "SATA0_PCLK"); + if (IS_ERR(sg->sata0_pclk)) { + dev_err(dev, "no SATA0 PCLK"); + return -ENODEV; + } + sg->sata1_pclk = devm_clk_get(dev, "SATA1_PCLK"); + if (IS_ERR(sg->sata1_pclk)) { + dev_err(dev, "no SATA1 PCLK"); + return -ENODEV; + } + + ret = clk_prepare_enable(sg->sata0_pclk); + if (ret) { + dev_err(dev, "failed to enable SATA0 PCLK\n"); + return ret; + } + ret = clk_prepare_enable(sg->sata1_pclk); + if (ret) { + dev_err(dev, "failed to enable SATA1 PCLK\n"); + clk_disable_unprepare(sg->sata0_pclk); + return ret; + } + + sg->sata0_reset = devm_reset_control_get_exclusive(dev, "sata0"); + if (IS_ERR(sg->sata0_reset)) { + dev_err(dev, "no SATA0 reset controller\n"); + clk_disable_unprepare(sg->sata1_pclk); + clk_disable_unprepare(sg->sata0_pclk); + return PTR_ERR(sg->sata0_reset); + } + sg->sata1_reset = devm_reset_control_get_exclusive(dev, "sata1"); + if (IS_ERR(sg->sata1_reset)) { + dev_err(dev, "no SATA1 reset controller\n"); + clk_disable_unprepare(sg->sata1_pclk); + clk_disable_unprepare(sg->sata0_pclk); + return PTR_ERR(sg->sata1_reset); + } + + sata_id = readl(sg->base + GEMINI_SATA_ID); + sata_phy_id = readl(sg->base + GEMINI_SATA_PHY_ID); + sg->sata_bridge = true; + clk_disable(sg->sata0_pclk); + clk_disable(sg->sata1_pclk); + + dev_info(dev, "SATA ID %08x, PHY ID: %08x\n", sata_id, sata_phy_id); + + return 0; +} + +static int gemini_setup_ide_pins(struct device *dev) +{ + struct pinctrl *p; + struct pinctrl_state *ide_state; + int ret; + + p = devm_pinctrl_get(dev); + if (IS_ERR(p)) + return PTR_ERR(p); + + ide_state = pinctrl_lookup_state(p, "ide"); + if (IS_ERR(ide_state)) + return PTR_ERR(ide_state); + + ret = pinctrl_select_state(p, ide_state); + if (ret) { + dev_err(dev, "could not select IDE state\n"); + return ret; + } + + return 0; +} + +static int gemini_sata_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct sata_gemini *sg; + struct regmap *map; + enum gemini_muxmode muxmode; + u32 gmode; + u32 gmask; + int ret; + + sg = devm_kzalloc(dev, sizeof(*sg), GFP_KERNEL); + if (!sg) + return -ENOMEM; + sg->dev = dev; + + sg->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(sg->base)) + return PTR_ERR(sg->base); + + map = syscon_regmap_lookup_by_phandle(np, "syscon"); + if (IS_ERR(map)) { + dev_err(dev, "no global syscon\n"); + return PTR_ERR(map); + } + + /* Set up the SATA bridge if need be */ + if (of_property_read_bool(np, "cortina,gemini-enable-sata-bridge")) { + ret = gemini_sata_bridge_init(sg); + if (ret) + return ret; + } + + if (of_property_read_bool(np, "cortina,gemini-enable-ide-pins")) + sg->ide_pins = true; + + if (!sg->sata_bridge && !sg->ide_pins) { + dev_err(dev, "neither SATA bridge or IDE output enabled\n"); + ret = -EINVAL; + goto out_unprep_clk; + } + + ret = of_property_read_u32(np, "cortina,gemini-ata-muxmode", &muxmode); + if (ret) { + dev_err(dev, "could not parse ATA muxmode\n"); + goto out_unprep_clk; + } + if (muxmode > GEMINI_MUXMODE_3) { + dev_err(dev, "illegal muxmode %d\n", muxmode); + ret = -EINVAL; + goto out_unprep_clk; + } + sg->muxmode = muxmode; + gmask = GEMINI_IDE_IOMUX_MASK; + gmode = (muxmode << GEMINI_IDE_IOMUX_SHIFT); + + ret = regmap_update_bits(map, GEMINI_GLOBAL_MISC_CTRL, gmask, gmode); + if (ret) { + dev_err(dev, "unable to set up IDE muxing\n"); + ret = -ENODEV; + goto out_unprep_clk; + } + + /* + * Route out the IDE pins if desired. + * This is done by looking up a special pin control state called + * "ide" that will route out the IDE pins. + */ + if (sg->ide_pins) { + ret = gemini_setup_ide_pins(dev); + if (ret) + return ret; + } + + dev_info(dev, "set up the Gemini IDE/SATA nexus\n"); + platform_set_drvdata(pdev, sg); + sg_singleton = sg; + + return 0; + +out_unprep_clk: + if (sg->sata_bridge) { + clk_unprepare(sg->sata1_pclk); + clk_unprepare(sg->sata0_pclk); + } + return ret; +} + +static int gemini_sata_remove(struct platform_device *pdev) +{ + struct sata_gemini *sg = platform_get_drvdata(pdev); + + if (sg->sata_bridge) { + clk_unprepare(sg->sata1_pclk); + clk_unprepare(sg->sata0_pclk); + } + sg_singleton = NULL; + + return 0; +} + +static const struct of_device_id gemini_sata_of_match[] = { + { .compatible = "cortina,gemini-sata-bridge", }, + { /* sentinel */ } +}; + +static struct platform_driver gemini_sata_driver = { + .driver = { + .name = DRV_NAME, + .of_match_table = of_match_ptr(gemini_sata_of_match), + }, + .probe = gemini_sata_probe, + .remove = gemini_sata_remove, +}; +module_platform_driver(gemini_sata_driver); + +MODULE_DESCRIPTION("low level driver for Cortina Systems Gemini SATA bridge"); +MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRV_NAME); |