* [PATCH v5 2/2] phy: intel-lgm-emmc: Add support for eMMC PHY
2019-09-04 5:53 [PATCH v5 1/2] dt-bindings: phy: intel-emmc-phy: Add YAML schema for LGM eMMC PHY Ramuthevar,Vadivel MuruganX
@ 2019-09-04 5:53 ` Ramuthevar,Vadivel MuruganX
2019-09-17 14:23 ` [PATCH v5 1/2] dt-bindings: phy: intel-emmc-phy: Add YAML schema for LGM " Rob Herring
1 sibling, 0 replies; 5+ messages in thread
From: Ramuthevar,Vadivel MuruganX @ 2019-09-04 5:53 UTC (permalink / raw)
To: kishon
Cc: linux-kernel, devicetree, robh, andriy.shevchenko,
cheol.yong.kim, qi-ming.wu, peter.harliman.liem,
vadivel.muruganx.ramuthevar
From: Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@linux.intel.com>
Add support for eMMC PHY on Intel's Lightning Mountain SoC.
Signed-off-by: Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
---
drivers/phy/Kconfig | 1 +
drivers/phy/Makefile | 1 +
drivers/phy/intel/Kconfig | 9 ++
drivers/phy/intel/Makefile | 2 +
drivers/phy/intel/phy-intel-emmc.c | 283 +++++++++++++++++++++++++++++++++++++
5 files changed, 296 insertions(+)
create mode 100644 drivers/phy/intel/Kconfig
create mode 100644 drivers/phy/intel/Makefile
create mode 100644 drivers/phy/intel/phy-intel-emmc.c
diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 0263db2ac874..b3ed94b98d9b 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -69,5 +69,6 @@ source "drivers/phy/socionext/Kconfig"
source "drivers/phy/st/Kconfig"
source "drivers/phy/tegra/Kconfig"
source "drivers/phy/ti/Kconfig"
+source "drivers/phy/intel/Kconfig"
endmenu
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index c96a1afc95bd..310c149a9df5 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -18,6 +18,7 @@ obj-y += broadcom/ \
cadence/ \
freescale/ \
hisilicon/ \
+ intel/ \
lantiq/ \
marvell/ \
motorola/ \
diff --git a/drivers/phy/intel/Kconfig b/drivers/phy/intel/Kconfig
new file mode 100644
index 000000000000..4ea6a8897cd7
--- /dev/null
+++ b/drivers/phy/intel/Kconfig
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Phy drivers for Intel Lightning Mountain(LGM) platform
+#
+config PHY_INTEL_EMMC
+ tristate "Intel EMMC PHY driver"
+ select GENERIC_PHY
+ help
+ Enable this to support the Intel EMMC PHY
diff --git a/drivers/phy/intel/Makefile b/drivers/phy/intel/Makefile
new file mode 100644
index 000000000000..6b876a75599d
--- /dev/null
+++ b/drivers/phy/intel/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_PHY_INTEL_EMMC) += phy-intel-emmc.o
diff --git a/drivers/phy/intel/phy-intel-emmc.c b/drivers/phy/intel/phy-intel-emmc.c
new file mode 100644
index 000000000000..1a358e7fd236
--- /dev/null
+++ b/drivers/phy/intel/phy-intel-emmc.c
@@ -0,0 +1,283 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel eMMC PHY driver
+ * Copyright (C) 2019 Intel, Corp.
+ */
+
+#include <linux/bits.h>
+#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>
+
+/* eMMC phy register definitions */
+#define EMMC_PHYCTRL0_REG 0xa8
+#define DR_TY_MASK GENMASK(30, 28)
+#define DR_TY_SHIFT(x) (((x) << 28) & DR_TY_MASK)
+#define OTAPDLYENA BIT(14)
+#define OTAPDLYSEL_MASK GENMASK(13, 10)
+#define OTAPDLYSEL_SHIFT(x) (((x) << 10) & OTAPDLYSEL_MASK)
+
+#define EMMC_PHYCTRL1_REG 0xac
+#define PDB_MASK BIT(0)
+#define PDB_SHIFT(x) (((x) << 0) & PDB_MASK)
+#define ENDLL_MASK BIT(7)
+#define ENDLL_SHIFT(x) (((x) << 7) & ENDLL_MASK)
+
+#define EMMC_PHYCTRL2_REG 0xb0
+#define FRQSEL_25M 0
+#define FRQSEL_50M 1
+#define FRQSEL_100M 2
+#define FRQSEL_150M 3
+#define FRQSEL_MASK GENMASK(24, 22)
+#define FRQSEL_SHIFT(x) (((x) << 22) & FRQSEL_MASK)
+
+#define EMMC_PHYSTAT_REG 0xbc
+#define CALDONE_MASK BIT(9)
+#define DLLRDY_MASK BIT(8)
+#define IS_CALDONE(x) ((x) & CALDONE_MASK)
+#define IS_DLLRDY(x) ((x) & DLLRDY_MASK)
+
+struct intel_emmc_phy {
+ struct regmap *syscfg;
+ struct clk *emmcclk;
+};
+
+static int intel_emmc_phy_power(struct phy *phy, bool on_off)
+{
+ struct intel_emmc_phy *priv = phy_get_drvdata(phy);
+ unsigned int caldone;
+ unsigned int dllrdy;
+ unsigned int freqsel;
+ unsigned long rate;
+ int ret, quot;
+
+ /*
+ * Keep phyctrl_pdb and phyctrl_endll low to allow
+ * initialization of CALIO state M/C DFFs
+ */
+ ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL1_REG, PDB_MASK,
+ PDB_SHIFT(0));
+ if (ret) {
+ dev_err(&phy->dev, "CALIO power down bar failed: %d\n", ret);
+ return ret;
+ }
+
+ /* Already finish power_off above */
+ if (!on_off)
+ return 0;
+
+ rate = clk_get_rate(priv->emmcclk);
+ quot = DIV_ROUND_CLOSEST(rate, 50000000);
+ if (quot > FRQSEL_150M)
+ dev_warn(&phy->dev, "Unsupported rate: %lu\n", rate);
+ freqsel = clamp_t(int, quot, FRQSEL_25M, FRQSEL_150M);
+
+ /*
+ * 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(5);
+
+ ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL1_REG, PDB_MASK,
+ PDB_SHIFT(1));
+ if (ret) {
+ dev_err(&phy->dev, "CALIO power down bar failed: %d\n", ret);
+ return ret;
+ }
+
+ /*
+ * 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(priv->syscfg, EMMC_PHYSTAT_REG,
+ caldone, IS_CALDONE(caldone),
+ 0, 50);
+ if (ret) {
+ dev_err(&phy->dev, "caldone failed, ret=%d\n", ret);
+ return ret;
+ }
+
+ /* Set the frequency of the DLL operation */
+ ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL2_REG, FRQSEL_MASK,
+ FRQSEL_SHIFT(freqsel));
+ if (ret) {
+ dev_err(&phy->dev, "set the frequency of dll failed:%d\n", ret);
+ return ret;
+ }
+
+ /* Turn on the DLL */
+ ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL1_REG, ENDLL_MASK,
+ ENDLL_SHIFT(1));
+ if (ret) {
+ dev_err(&phy->dev, "turn on the dll failed: %d\n", ret);
+ return ret;
+ }
+
+ /*
+ * 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(priv->syscfg,
+ EMMC_PHYSTAT_REG,
+ dllrdy, IS_DLLRDY(dllrdy),
+ 0, 50 * USEC_PER_MSEC);
+ if (ret) {
+ dev_err(&phy->dev, "dllrdy failed. ret=%d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int intel_emmc_phy_init(struct phy *phy)
+{
+ struct intel_emmc_phy *priv = phy_get_drvdata(phy);
+
+ /*
+ * 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 just return it like
+ * any other error to user.
+ *
+ */
+ priv->emmcclk = clk_get_optional(&phy->dev, "emmcclk");
+ if (IS_ERR(priv->emmcclk)) {
+ dev_err(&phy->dev, "ERROR: getting emmcclk\n");
+ return PTR_ERR(priv->emmcclk);
+ }
+
+ return 0;
+}
+
+static int intel_emmc_phy_exit(struct phy *phy)
+{
+ struct intel_emmc_phy *priv = phy_get_drvdata(phy);
+
+ clk_put(priv->emmcclk);
+
+ return 0;
+}
+
+static int intel_emmc_phy_power_on(struct phy *phy)
+{
+ struct intel_emmc_phy *priv = phy_get_drvdata(phy);
+ int ret;
+
+ /* Drive impedance: 50 Ohm */
+ ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL0_REG, DR_TY_MASK,
+ DR_TY_SHIFT(6));
+ if (ret) {
+ dev_err(&phy->dev, "ERROR set drive-impednce-50ohm: %d\n", ret);
+ return ret;
+ }
+
+ /* Output tap delay: disable */
+ ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL0_REG, OTAPDLYENA,
+ 0);
+ if (ret) {
+ dev_err(&phy->dev, "ERROR Set output tap delay : %d\n", ret);
+ return ret;
+ }
+
+ /* Output tap delay */
+ ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL0_REG,
+ OTAPDLYSEL_MASK, OTAPDLYSEL_SHIFT(4));
+ if (ret) {
+ dev_err(&phy->dev, "ERROR: output tap dly select: %d\n", ret);
+ return ret;
+ }
+
+ /* Power up eMMC phy analog blocks */
+ return intel_emmc_phy_power(phy, true);
+}
+
+static int intel_emmc_phy_power_off(struct phy *phy)
+{
+ /* Power down eMMC phy analog blocks */
+ return intel_emmc_phy_power(phy, false);
+}
+
+static const struct phy_ops ops = {
+ .init = intel_emmc_phy_init,
+ .exit = intel_emmc_phy_exit,
+ .power_on = intel_emmc_phy_power_on,
+ .power_off = intel_emmc_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static int intel_emmc_phy_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct intel_emmc_phy *priv;
+ struct phy *generic_phy;
+ struct phy_provider *phy_provider;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ /* Get eMMC phy (accessed via chiptop) regmap */
+ priv->syscfg = syscon_regmap_lookup_by_phandle(np, "intel,syscon");
+ if (IS_ERR(priv->syscfg)) {
+ dev_err(dev, "failed to find syscon\n");
+ return PTR_ERR(priv->syscfg);
+ }
+
+ generic_phy = devm_phy_create(dev, np, &ops);
+ if (IS_ERR(generic_phy)) {
+ dev_err(dev, "failed to create PHY\n");
+ return PTR_ERR(generic_phy);
+ }
+
+ phy_set_drvdata(generic_phy, priv);
+ 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 intel_emmc_phy_dt_ids[] = {
+ { .compatible = "intel,lgm-emmc-phy" },
+ {}
+};
+
+MODULE_DEVICE_TABLE(of, intel_emmc_phy_dt_ids);
+
+static struct platform_driver intel_emmc_driver = {
+ .probe = intel_emmc_phy_probe,
+ .driver = {
+ .name = "intel-emmc-phy",
+ .of_match_table = intel_emmc_phy_dt_ids,
+ },
+};
+
+module_platform_driver(intel_emmc_driver);
+
+MODULE_AUTHOR("Peter Harliman Liem <peter.harliman.liem@intel.com>");
+MODULE_DESCRIPTION("Intel eMMC PHY driver");
--
2.11.0
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH v5 1/2] dt-bindings: phy: intel-emmc-phy: Add YAML schema for LGM eMMC PHY
2019-09-04 5:53 [PATCH v5 1/2] dt-bindings: phy: intel-emmc-phy: Add YAML schema for LGM eMMC PHY Ramuthevar,Vadivel MuruganX
2019-09-04 5:53 ` [PATCH v5 2/2] phy: intel-lgm-emmc: Add support for " Ramuthevar,Vadivel MuruganX
@ 2019-09-17 14:23 ` Rob Herring
2019-09-18 2:23 ` Ramuthevar, Vadivel MuruganX
1 sibling, 1 reply; 5+ messages in thread
From: Rob Herring @ 2019-09-17 14:23 UTC (permalink / raw)
To: Ramuthevar,Vadivel MuruganX
Cc: kishon, linux-kernel, devicetree, andriy.shevchenko,
cheol.yong.kim, qi-ming.wu, peter.harliman.liem
On Wed, Sep 04, 2019 at 01:53:43PM +0800, Ramuthevar,Vadivel MuruganX wrote:
> From: Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@linux.intel.com>
>
> Add a YAML schema to use the host controller driver with the
> eMMC PHY on Intel's Lightning Mountain SoC.
>
> Signed-off-by: Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@linux.intel.com>
> ---
> changes in v5:
> - earlier Review-by tag given by Rob
> - rework done with syscon parent node.
>
> changes in v4:
> - As per Rob's review: validate 5.2 and 5.3
> - drop unrelated items.
>
> changes in v3:
> - resolve 'make dt_binding_check' warnings
>
> changes in v2:
> As per Rob Herring review comments, the following updates
> - change GPL-2.0 -> (GPL-2.0-only OR BSD-2-Clause)
> - filename is the compatible string plus .yaml
> - LGM: Lightning Mountain
> - update maintainer
> - add intel,syscon under property list
> - keep one example instead of two
> ---
> .../bindings/phy/intel,lgm-emmc-phy.yaml | 69 ++++++++++++++++++++++
> 1 file changed, 69 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/phy/intel,lgm-emmc-phy.yaml
>
> diff --git a/Documentation/devicetree/bindings/phy/intel,lgm-emmc-phy.yaml b/Documentation/devicetree/bindings/phy/intel,lgm-emmc-phy.yaml
> new file mode 100644
> index 000000000000..8f6ac8b3da42
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/phy/intel,lgm-emmc-phy.yaml
> @@ -0,0 +1,69 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/phy/intel,lgm-emmc-phy.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Intel Lightning Mountain(LGM) eMMC PHY Device Tree Bindings
> +
> +maintainers:
> + - Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@linux.intel.com>
> +
> +description: Bindings for eMMC PHY on Intel's Lightning Mountain SoC, syscon
> + node is used to reference the base address of eMMC phy registers.
> +
> +select:
> + properties:
> + compatible:
> + contains:
> + const: intel,lgm-syscon
This, plus...
> +
> + reg:
> + maxItems: 1
> +
> + required:
> + - compatible
> + - reg
> +
> +properties:
> + "#phy-cells":
> + const: 0
> +
> + compatible:
> + contains:
> + const: intel,lgm-emmc-phy
...this should not pass validation as they contradict each other.
> +
> + reg:
> + maxItems: 1
> +
> + clocks:
> + maxItems: 1
> +
> + clock-names:
> + maxItems: 1
> +
> +required:
> + - "#phy-cells"
> + - compatible
> + - reg
> + - clocks
> + - clock-names
> +
> +examples:
> + - |
> + sysconf: chiptop@e0200000 {
> + compatible = "intel,lgm-syscon";
> + reg = <0xe0200000 0x100>;
I'm still waiting for a complete description of what all is in this
block.
> +
> + emmc-phy: emmc-phy {
> + compatible = "intel,lgm-emmc-phy";
> + reg = <0x00a8 0x4>,
> + <0x00ac 0x4>,
> + <0x00b0 0x4>,
> + <0x00b4 0x4>;
Looks contiguous and can be a single entry:
<0xa8 0x10>
> + clocks = <&emmc>;
> + clock-names = "emmcclk";
> + #phy-cells = <0>;
> + };
> + };
> +...
> --
> 2.11.0
>
^ permalink raw reply [flat|nested] 5+ messages in thread