Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 379 insertions, 0 deletions

diff --git a/drivers/phy/rockchip/phy-rockchip-emmc.c b/drivers/phy/rockchip/phy-rockchip-emmc.c
new file mode 100644
index 000000000..b237360f9
--- /dev/null
+++ b/drivers/phy/rockchip/phy-rockchip-emmc.c
@@ -0,0 +1,379 @@
+/*
+ * Rockchip emmc PHY driver
+ *
+ * Copyright (C) 2016 Shawn Lin <shawn.lin@rock-chips.com>
+ * Copyright (C) 2016 ROCKCHIP, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+/*
+ * The higher 16-bit of this register is used for write protection
+ * only if BIT(x + 16) set to 1 the BIT(x) can be written.
+ */
+#define HIWORD_UPDATE(val, mask, shift) \
+		((val) << (shift) | (mask) << ((shift) + 16))
+
+/* Register definition */
+#define GRF_EMMCPHY_CON0		0x0
+#define GRF_EMMCPHY_CON1		0x4
+#define GRF_EMMCPHY_CON2		0x8
+#define GRF_EMMCPHY_CON3		0xc
+#define GRF_EMMCPHY_CON4		0x10
+#define GRF_EMMCPHY_CON5		0x14
+#define GRF_EMMCPHY_CON6		0x18
+#define GRF_EMMCPHY_STATUS		0x20
+
+#define PHYCTRL_PDB_MASK		0x1
+#define PHYCTRL_PDB_SHIFT		0x0
+#define PHYCTRL_PDB_PWR_ON		0x1
+#define PHYCTRL_PDB_PWR_OFF		0x0
+#define PHYCTRL_ENDLL_MASK		0x1
+#define PHYCTRL_ENDLL_SHIFT		0x1
+#define PHYCTRL_ENDLL_ENABLE		0x1
+#define PHYCTRL_ENDLL_DISABLE		0x0
+#define PHYCTRL_CALDONE_MASK		0x1
+#define PHYCTRL_CALDONE_SHIFT		0x6
+#define PHYCTRL_CALDONE_DONE		0x1
+#define PHYCTRL_CALDONE_GOING		0x0
+#define PHYCTRL_DLLRDY_MASK		0x1
+#define PHYCTRL_DLLRDY_SHIFT		0x5
+#define PHYCTRL_DLLRDY_DONE		0x1
+#define PHYCTRL_DLLRDY_GOING		0x0
+#define PHYCTRL_FREQSEL_200M		0x0
+#define PHYCTRL_FREQSEL_50M		0x1
+#define PHYCTRL_FREQSEL_100M		0x2
+#define PHYCTRL_FREQSEL_150M		0x3
+#define PHYCTRL_FREQSEL_MASK		0x3
+#define PHYCTRL_FREQSEL_SHIFT		0xc
+#define PHYCTRL_DR_MASK			0x7
+#define PHYCTRL_DR_SHIFT		0x4
+#define PHYCTRL_DR_50OHM		0x0
+#define PHYCTRL_DR_33OHM		0x1
+#define PHYCTRL_DR_66OHM		0x2
+#define PHYCTRL_DR_100OHM		0x3
+#define PHYCTRL_DR_40OHM		0x4
+#define PHYCTRL_OTAPDLYENA		0x1
+#define PHYCTRL_OTAPDLYENA_MASK		0x1
+#define PHYCTRL_OTAPDLYENA_SHIFT	0xb
+#define PHYCTRL_OTAPDLYSEL_MASK		0xf
+#define PHYCTRL_OTAPDLYSEL_SHIFT	0x7
+
+#define PHYCTRL_IS_CALDONE(x) \
+	((((x) >> PHYCTRL_CALDONE_SHIFT) & \
+	  PHYCTRL_CALDONE_MASK) == PHYCTRL_CALDONE_DONE)
+#define PHYCTRL_IS_DLLRDY(x) \
+	((((x) >> PHYCTRL_DLLRDY_SHIFT) & \
+	  PHYCTRL_DLLRDY_MASK) == PHYCTRL_DLLRDY_DONE)
+
+struct rockchip_emmc_phy {
+	unsigned int	reg_offset;
+	struct regmap	*reg_base;
+	struct clk	*emmcclk;
+};
+
+static int rockchip_emmc_phy_power(struct phy *phy, bool on_off)
+{
+	struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
+	unsigned int caldone;
+	unsigned int dllrdy;
+	unsigned int freqsel = PHYCTRL_FREQSEL_200M;
+	unsigned long rate;
+	int ret;
+
+	/*
+	 * Keep phyctrl_pdb and phyctrl_endll low to allow
+	 * initialization of CALIO state M/C DFFs
+	 */
+	regmap_write(rk_phy->reg_base,
+		     rk_phy->reg_offset + GRF_EMMCPHY_CON6,
+		     HIWORD_UPDATE(PHYCTRL_PDB_PWR_OFF,
+				   PHYCTRL_PDB_MASK,
+				   PHYCTRL_PDB_SHIFT));
+	regmap_write(rk_phy->reg_base,
+		     rk_phy->reg_offset + GRF_EMMCPHY_CON6,
+		     HIWORD_UPDATE(PHYCTRL_ENDLL_DISABLE,
+				   PHYCTRL_ENDLL_MASK,
+				   PHYCTRL_ENDLL_SHIFT));
+
+	/* Already finish power_off above */
+	if (on_off == PHYCTRL_PDB_PWR_OFF)
+		return 0;
+
+	rate = clk_get_rate(rk_phy->emmcclk);
+
+	if (rate != 0) {
+		unsigned long ideal_rate;
+		unsigned long diff;
+
+		switch (rate) {
+		case 1 ... 74999999:
+			ideal_rate = 50000000;
+			freqsel = PHYCTRL_FREQSEL_50M;
+			break;
+		case 75000000 ... 124999999:
+			ideal_rate = 100000000;
+			freqsel = PHYCTRL_FREQSEL_100M;
+			break;
+		case 125000000 ... 174999999:
+			ideal_rate = 150000000;
+			freqsel = PHYCTRL_FREQSEL_150M;
+			break;
+		default:
+			ideal_rate = 200000000;
+			break;
+		}
+
+		diff = (rate > ideal_rate) ?
+			rate - ideal_rate : ideal_rate - rate;
+
+		/*
+		 * In order for tuning delays to be accurate we need to be
+		 * pretty spot on for the DLL range, so warn if we're too
+		 * far off.  Also warn if we're above the 200 MHz max.  Don't
+		 * warn for really slow rates since we won't be tuning then.
+		 */
+		if ((rate > 50000000 && diff > 15000000) || (rate > 200000000))
+			dev_warn(&phy->dev, "Unsupported rate: %lu\n", rate);
+	}
+
+	/*
+	 * According to the user manual, calpad calibration
+	 * cycle takes more than 2us without the minimal recommended
+	 * value, so we may need a little margin here
+	 */
+	udelay(3);
+	regmap_write(rk_phy->reg_base,
+		     rk_phy->reg_offset + GRF_EMMCPHY_CON6,
+		     HIWORD_UPDATE(PHYCTRL_PDB_PWR_ON,
+				   PHYCTRL_PDB_MASK,
+				   PHYCTRL_PDB_SHIFT));
+
+	/*
+	 * According to the user manual, it asks driver to wait 5us for
+	 * calpad busy trimming. However it is documented that this value is
+	 * PVT(A.K.A process,voltage and temperature) relevant, so some
+	 * failure cases are found which indicates we should be more tolerant
+	 * to calpad busy trimming.
+	 */
+	ret = regmap_read_poll_timeout(rk_phy->reg_base,
+				       rk_phy->reg_offset + GRF_EMMCPHY_STATUS,
+				       caldone, PHYCTRL_IS_CALDONE(caldone),
+				       0, 50);
+	if (ret) {
+		pr_err("%s: caldone failed, ret=%d\n", __func__, ret);
+		return ret;
+	}
+
+	/* Set the frequency of the DLL operation */
+	regmap_write(rk_phy->reg_base,
+		     rk_phy->reg_offset + GRF_EMMCPHY_CON0,
+		     HIWORD_UPDATE(freqsel, PHYCTRL_FREQSEL_MASK,
+				   PHYCTRL_FREQSEL_SHIFT));
+
+	/* Turn on the DLL */
+	regmap_write(rk_phy->reg_base,
+		     rk_phy->reg_offset + GRF_EMMCPHY_CON6,
+		     HIWORD_UPDATE(PHYCTRL_ENDLL_ENABLE,
+				   PHYCTRL_ENDLL_MASK,
+				   PHYCTRL_ENDLL_SHIFT));
+
+	/*
+	 * We turned on the DLL even though the rate was 0 because we the
+	 * clock might be turned on later.  ...but we can't wait for the DLL
+	 * to lock when the rate is 0 because it will never lock with no
+	 * input clock.
+	 *
+	 * Technically we should be checking the lock later when the clock
+	 * is turned on, but for now we won't.
+	 */
+	if (rate == 0)
+		return 0;
+
+	/*
+	 * After enabling analog DLL circuits docs say that we need 10.2 us if
+	 * our source clock is at 50 MHz and that lock time scales linearly
+	 * with clock speed.  If we are powering on the PHY and the card clock
+	 * is super slow (like 100 kHZ) this could take as long as 5.1 ms as
+	 * per the math: 10.2 us * (50000000 Hz / 100000 Hz) => 5.1 ms
+	 * Hopefully we won't be running at 100 kHz, but we should still make
+	 * sure we wait long enough.
+	 *
+	 * NOTE: There appear to be corner cases where the DLL seems to take
+	 * extra long to lock for reasons that aren't understood.  In some
+	 * extreme cases we've seen it take up to over 10ms (!).  We'll be
+	 * generous and give it 50ms.
+	 */
+	ret = regmap_read_poll_timeout(rk_phy->reg_base,
+				       rk_phy->reg_offset + GRF_EMMCPHY_STATUS,
+				       dllrdy, PHYCTRL_IS_DLLRDY(dllrdy),
+				       0, 50 * USEC_PER_MSEC);
+	if (ret) {
+		pr_err("%s: dllrdy failed. ret=%d\n", __func__, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int rockchip_emmc_phy_init(struct phy *phy)
+{
+	struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
+	int ret = 0;
+
+	/*
+	 * We purposely get the clock here and not in probe to avoid the
+	 * circular dependency problem.  We expect:
+	 * - PHY driver to probe
+	 * - SDHCI driver to start probe
+	 * - SDHCI driver to register it's clock
+	 * - SDHCI driver to get the PHY
+	 * - SDHCI driver to init the PHY
+	 *
+	 * The clock is optional, so upon any error we just set to NULL.
+	 *
+	 * NOTE: we don't do anything special for EPROBE_DEFER here.  Given the
+	 * above expected use case, EPROBE_DEFER isn't sensible to expect, so
+	 * it's just like any other error.
+	 */
+	rk_phy->emmcclk = clk_get(&phy->dev, "emmcclk");
+	if (IS_ERR(rk_phy->emmcclk)) {
+		dev_dbg(&phy->dev, "Error getting emmcclk: %d\n", ret);
+		rk_phy->emmcclk = NULL;
+	}
+
+	return ret;
+}
+
+static int rockchip_emmc_phy_exit(struct phy *phy)
+{
+	struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
+
+	clk_put(rk_phy->emmcclk);
+
+	return 0;
+}
+
+static int rockchip_emmc_phy_power_off(struct phy *phy)
+{
+	/* Power down emmc phy analog blocks */
+	return rockchip_emmc_phy_power(phy, PHYCTRL_PDB_PWR_OFF);
+}
+
+static int rockchip_emmc_phy_power_on(struct phy *phy)
+{
+	struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
+
+	/* Drive impedance: 50 Ohm */
+	regmap_write(rk_phy->reg_base,
+		     rk_phy->reg_offset + GRF_EMMCPHY_CON6,
+		     HIWORD_UPDATE(PHYCTRL_DR_50OHM,
+				   PHYCTRL_DR_MASK,
+				   PHYCTRL_DR_SHIFT));
+
+	/* Output tap delay: enable */
+	regmap_write(rk_phy->reg_base,
+		     rk_phy->reg_offset + GRF_EMMCPHY_CON0,
+		     HIWORD_UPDATE(PHYCTRL_OTAPDLYENA,
+				   PHYCTRL_OTAPDLYENA_MASK,
+				   PHYCTRL_OTAPDLYENA_SHIFT));
+
+	/* Output tap delay */
+	regmap_write(rk_phy->reg_base,
+		     rk_phy->reg_offset + GRF_EMMCPHY_CON0,
+		     HIWORD_UPDATE(4,
+				   PHYCTRL_OTAPDLYSEL_MASK,
+				   PHYCTRL_OTAPDLYSEL_SHIFT));
+
+	/* Power up emmc phy analog blocks */
+	return rockchip_emmc_phy_power(phy, PHYCTRL_PDB_PWR_ON);
+}
+
+static const struct phy_ops ops = {
+	.init		= rockchip_emmc_phy_init,
+	.exit		= rockchip_emmc_phy_exit,
+	.power_on	= rockchip_emmc_phy_power_on,
+	.power_off	= rockchip_emmc_phy_power_off,
+	.owner		= THIS_MODULE,
+};
+
+static int rockchip_emmc_phy_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct rockchip_emmc_phy *rk_phy;
+	struct phy *generic_phy;
+	struct phy_provider *phy_provider;
+	struct regmap *grf;
+	unsigned int reg_offset;
+
+	if (!dev->parent || !dev->parent->of_node)
+		return -ENODEV;
+
+	grf = syscon_node_to_regmap(dev->parent->of_node);
+	if (IS_ERR(grf)) {
+		dev_err(dev, "Missing rockchip,grf property\n");
+		return PTR_ERR(grf);
+	}
+
+	rk_phy = devm_kzalloc(dev, sizeof(*rk_phy), GFP_KERNEL);
+	if (!rk_phy)
+		return -ENOMEM;
+
+	if (of_property_read_u32(dev->of_node, "reg", &reg_offset)) {
+		dev_err(dev, "missing reg property in node %s\n",
+			dev->of_node->name);
+		return -EINVAL;
+	}
+
+	rk_phy->reg_offset = reg_offset;
+	rk_phy->reg_base = grf;
+
+	generic_phy = devm_phy_create(dev, dev->of_node, &ops);
+	if (IS_ERR(generic_phy)) {
+		dev_err(dev, "failed to create PHY\n");
+		return PTR_ERR(generic_phy);
+	}
+
+	phy_set_drvdata(generic_phy, rk_phy);
+	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+
+	return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id rockchip_emmc_phy_dt_ids[] = {
+	{ .compatible = "rockchip,rk3399-emmc-phy" },
+	{}
+};
+
+MODULE_DEVICE_TABLE(of, rockchip_emmc_phy_dt_ids);
+
+static struct platform_driver rockchip_emmc_driver = {
+	.probe		= rockchip_emmc_phy_probe,
+	.driver		= {
+		.name	= "rockchip-emmc-phy",
+		.of_match_table = rockchip_emmc_phy_dt_ids,
+	},
+};
+
+module_platform_driver(rockchip_emmc_driver);
+
+MODULE_AUTHOR("Shawn Lin <shawn.lin@rock-chips.com>");
+MODULE_DESCRIPTION("Rockchip EMMC PHY driver");
+MODULE_LICENSE("GPL v2");