Re: [PATCH 4/5] phy: cygnus: pcie: Add Cygnus PCIe PHY support

From: Kishon Vijay Abraham I
Date: Thu May 21 2015 - 09:19:25 EST




On Wednesday 20 May 2015 06:53 AM, Ray Jui wrote:
This patch adds the PCIe PHY support for the Broadcom PCIe RC interface

Signed-off-by: Ray Jui <rjui@xxxxxxxxxxxx>
Reviewed-by: Arun Parameswaran <aparames@xxxxxxxxxxxx>
Reviewed-by: JD (Jiandong) Zheng <jdzheng@xxxxxxxxxxxx>
Reviewed-by: Scott Branden <sbranden@xxxxxxxxxxxx>
---
drivers/phy/Kconfig | 15 ++
drivers/phy/Makefile | 1 +
drivers/phy/phy-cygnus-pcie.c | 340 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 356 insertions(+)
create mode 100644 drivers/phy/phy-cygnus-pcie.c

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 2664285..8250169 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -35,6 +35,21 @@ config ARMADA375_USBCLUSTER_PHY
depends on OF
select GENERIC_PHY

+config PHY_CYGNUS_PCIE
+ bool "Broadcom Cygnus PCIe PHY driver"
+ depends on ARCH_BCM_CYGNUS
+ select GENERIC_PHY
+ select PHY_IPROC_MDIO
+ default ARCH_BCM_CYGNUS
+ help
+ Enable this to support the Broadcom Cygnus PCIe PHY.
+
+ The host communicates with the PHY through the iProc MDC/MDIO
+ interface.
+
+ If unsure, say N.
+
+

trailing blank line
config PHY_DM816X_USB
tristate "TI dm816x USB PHY driver"
depends on ARCH_OMAP2PLUS
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index d989dd7b..6545950 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -5,6 +5,7 @@
obj-$(CONFIG_GENERIC_PHY) += phy-core.o
obj-$(CONFIG_PHY_BERLIN_USB) += phy-berlin-usb.o
obj-$(CONFIG_PHY_BERLIN_SATA) += phy-berlin-sata.o
+obj-$(CONFIG_PHY_CYGNUS_PCIE) += phy-cygnus-pcie.o
obj-$(CONFIG_PHY_DM816X_USB) += phy-dm816x-usb.o
obj-$(CONFIG_ARMADA375_USBCLUSTER_PHY) += phy-armada375-usb2.o
obj-$(CONFIG_BCM_KONA_USB2_PHY) += phy-bcm-kona-usb2.o
diff --git a/drivers/phy/phy-cygnus-pcie.c b/drivers/phy/phy-cygnus-pcie.c
new file mode 100644
index 0000000..5817cd4
--- /dev/null
+++ b/drivers/phy/phy-cygnus-pcie.c
@@ -0,0 +1,340 @@
+/*
+ * Copyright (C) 2015 Broadcom Corporation
+ *
+ * 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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/phy/iproc_mdio_phy.h>
+
+#define MAX_PHY_ADDR 0x1f
+
+#define PCIE_MDCDIV_VAL 0x3e
+
+#define PCIE_BLK_ADDR_OFFSET 0x1f
+#define PCIE_BLK_ADDR_MASK 0xff00
+#define PCIE_REG_ADDR_MASK 0x1f
+
+#define PCIE_SW_CTRL0_OFFSET 0x1000
+#define PCIE_SW_PWRDOWN_SHIFT 0
+
+#define PCIE_AFE1_100MHZ_C3_OFFSET 0x2103
+#define PCIE_AFE1_100MHZ_C3_VAL 0x2b1c
+
+#define CRMU_PCIE_CFG_OFFSET 0x00
+#define CRMU_PCIE1_PHY_IDDQ_SHIFT 10
+#define CRMU_PCIE0_PHY_IDDQ_SHIFT 2
+
+enum cygnus_pcie_phy_id {
+ CYGNUS_PHY_PCIE0 = 0,
+ CYGNUS_PHY_PCIE1,
+ MAX_NUM_PHYS,
+};
+
+struct cygnus_pcie_phy_core;
+
+/**
+ * struct cygnus_pcie_phy - Cygnus PCIe PHY device
+ * @core: pointer to the Cygnus PCIe PHY core control
+ * @id: internal ID to identify the Cygnus PCIe PHY
+ * @addr: PHY address used by MDC to communicate with the PHY
+ * @phy: pointer to the kernel PHY device
+ *
+ */
+struct cygnus_pcie_phy {
+ struct cygnus_pcie_phy_core *core;
+ enum cygnus_pcie_phy_id id;
+ unsigned addr;
+ struct phy *phy;
+};
+
+/**
+ * struct cygnus_pcie_phy_core - Cygnus PCIe PHY core control
+ * @dev: pointer to device
+ * @crmu: CRMU register base
+ * @lock: mutex to protect access to individual PHYs
+ * @phys: pointer to Cygnus PHY device
+ *
+ */
+struct cygnus_pcie_phy_core {
+ struct device *dev;
+ void __iomem *crmu;
+ struct mutex lock;
+ struct cygnus_pcie_phy phys[MAX_NUM_PHYS];
+};
+
+static int cygnus_pcie_phy_reg_read(unsigned phy_addr, unsigned reg_addr,
+ u16 *val)
+{
+ int ret;
+ u16 addr = (u16)(reg_addr & PCIE_BLK_ADDR_MASK);
+
+ ret = iproc_mdio_write(PCIE_MDCDIV_VAL, phy_addr, PCIE_BLK_ADDR_OFFSET,
+ addr);
+ if (ret)
+ return ret;
+
+ ret = iproc_mdio_read(PCIE_MDCDIV_VAL, phy_addr,
+ reg_addr & PCIE_REG_ADDR_MASK, val);
+ return ret;
+}
+
+static int cygnus_pcie_phy_reg_write(unsigned phy_addr, unsigned reg_addr,
+ u16 val)
+{
+ int ret;
+ u16 addr = (u16)(reg_addr & PCIE_BLK_ADDR_MASK);
+
+ ret = iproc_mdio_write(PCIE_MDCDIV_VAL, phy_addr, PCIE_BLK_ADDR_OFFSET,
+ addr);
+ if (ret)
+ return ret;
+
+ ret = iproc_mdio_write(PCIE_MDCDIV_VAL, phy_addr,
+ reg_addr & PCIE_REG_ADDR_MASK, val);
+ return ret;
+}
+
+static void cygnus_pcie_afe_enable_disable(void __iomem *reg,
+ enum cygnus_pcie_phy_id id,
+ bool enable)
+{
+ unsigned shift;
+ u32 val;
+
+ if (id == CYGNUS_PHY_PCIE0)
+ shift = CRMU_PCIE0_PHY_IDDQ_SHIFT;
+ else
+ shift = CRMU_PCIE1_PHY_IDDQ_SHIFT;
+
+ if (enable) {
+ val = readl(reg + CRMU_PCIE_CFG_OFFSET);
+ val &= ~BIT(shift);
+ writel(val, reg + CRMU_PCIE_CFG_OFFSET);
+ } else {
+ val = readl(reg + CRMU_PCIE_CFG_OFFSET);
+ val |= BIT(shift);
+ writel(val, reg + CRMU_PCIE_CFG_OFFSET);
+ }
+
+ /* wait for AFE to come up or shut down */
+ msleep(100);
+}
+
+static int cygnus_pcie_power_config(struct cygnus_pcie_phy *phy, bool on)
+{
+ struct cygnus_pcie_phy_core *core = phy->core;
+ u16 val;
+ int ret;
+
+ if (phy->id != CYGNUS_PHY_PCIE0 && phy->id != CYGNUS_PHY_PCIE1)
+ return -EINVAL;
+
+ if (on) {
+ /* enable AFE through the CRMU interface */
+ cygnus_pcie_afe_enable_disable(core->crmu, phy->id, true);
+
+ /* to get the reference clock configured */
+ ret = cygnus_pcie_phy_reg_write(phy->addr,
+ PCIE_AFE1_100MHZ_C3_OFFSET,
+ PCIE_AFE1_100MHZ_C3_VAL);
+ if (ret)
+ goto err_disable_afe;
+ cygnus_pcie_phy_reg_read(phy->addr,
+ PCIE_AFE1_100MHZ_C3_OFFSET, &val);
+ if (ret)
+ goto err_disable_afe;
+
+ msleep(20);
+
+ /* now toggle AFE */
+ cygnus_pcie_afe_enable_disable(core->crmu, phy->id, false);
+ cygnus_pcie_afe_enable_disable(core->crmu, phy->id, true);
+
+ dev_info(core->dev,
+ "pcie phy on, addr:0x%02x off:0x%04x val:0x%04x\n",
+ phy->addr, PCIE_AFE1_100MHZ_C3_OFFSET, val);
+ } else {
+ /* disable AFE through the CRMU interface */
+ cygnus_pcie_afe_enable_disable(core->crmu, phy->id, false);
+ dev_info(core->dev, "pcie phy off\n");
+ }
+
+ return 0;
+
+err_disable_afe:
+ cygnus_pcie_afe_enable_disable(core->crmu, phy->id, false);
+ return ret;
+}
+
+static int cygnus_pcie_phy_init(struct phy *p)
+{
+ return 0;
+}
+
+static int cygnus_pcie_phy_exit(struct phy *p)
+{
+ return 0;
+}

empty callbacks are not required.
+
+static int cygnus_pcie_phy_power_on(struct phy *p)
+{
+ struct cygnus_pcie_phy *phy = phy_get_drvdata(p);
+ struct cygnus_pcie_phy_core *core = phy->core;
+ int ret = 0;
+
+ mutex_lock(&core->lock);
+
+ switch (phy->id) {
+ case CYGNUS_PHY_PCIE0:
+ case CYGNUS_PHY_PCIE1:
+ ret = cygnus_pcie_power_config(phy, true);
+ if (ret)
+ dev_err(core->dev, "unable to power on PCIe PHY\n");
+ break;
+
+ default:
+ dev_err(core->dev, "PHY id not supported\n");
+ mutex_unlock(&core->lock);
+ return -EINVAL;
+ }
+
+ mutex_unlock(&core->lock);
+
+ return ret;
+}
+
+static int cygnus_pcie_phy_power_off(struct phy *p)
+{
+ struct cygnus_pcie_phy *phy = phy_get_drvdata(p);
+ struct cygnus_pcie_phy_core *core = phy->core;
+ int ret = 0;
+
+ mutex_lock(&core->lock);
+
+ switch (phy->id) {
+ case CYGNUS_PHY_PCIE0:
+ case CYGNUS_PHY_PCIE1:
+ ret = cygnus_pcie_power_config(phy, false);
+ if (ret)
+ dev_err(core->dev, "unable to power off PCIe PHY\n");
+ break;
+
+ default:
+ dev_err(core->dev, "PHY id not supported\n");
+ mutex_unlock(&core->lock);
+ break;
+ }
+
+ mutex_unlock(&core->lock);
+
+ return ret;
+}
+
+static struct phy_ops cygnus_pcie_phy_ops = {
+ .init = cygnus_pcie_phy_init,
+ .exit = cygnus_pcie_phy_exit,
+ .power_on = cygnus_pcie_phy_power_on,
+ .power_off = cygnus_pcie_phy_power_off,
+};
+
+static struct phy *cygnus_pcie_phy_xlate(struct device *dev,
+ struct of_phandle_args *args)
+{
+ struct cygnus_pcie_phy_core *core;
+ int id, phy_addr;
+
+ core = dev_get_drvdata(dev);
+ if (!core)
+ return ERR_PTR(-EINVAL);
+
+ id = args->args[0];
+ phy_addr = args->args[1];
+
+ if (WARN_ON(id >= MAX_NUM_PHYS))
+ return ERR_PTR(-ENODEV);
+
+ if (WARN_ON(phy_addr > MAX_PHY_ADDR))
+ return ERR_PTR(-ENODEV);
+
+ core->phys[id].addr = phy_addr;
+
+ return core->phys[id].phy;
+}
+
+static int cygnus_pcie_phy_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct cygnus_pcie_phy_core *core;
+ struct phy_provider *provider;
+ struct resource *res;
+ int i = 0;
+
+ core = devm_kzalloc(dev, sizeof(*core), GFP_KERNEL);
+ if (!core)
+ return -ENOMEM;
+
+ core->dev = dev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ core->crmu = devm_ioremap_resource(dev, res);
+ if (IS_ERR(core->crmu))
+ return PTR_ERR(core->crmu);
+
+ mutex_init(&core->lock);
+
+ for (i = 0; i < MAX_NUM_PHYS; i++) {
+ struct cygnus_pcie_phy *p = &core->phys[i];
+
+ p->phy = devm_phy_create(dev, NULL, &cygnus_pcie_phy_ops);
+ if (IS_ERR(p->phy)) {
+ dev_err(dev, "failed to create PHY\n");
+ return PTR_ERR(p->phy);
+ }
+
+ p->core = core;
+ p->id = i;
+ phy_set_drvdata(p->phy, p);
+ }
+
+ dev_set_drvdata(dev, core);
+
+ provider = devm_of_phy_provider_register(dev, cygnus_pcie_phy_xlate);
+ if (IS_ERR(provider)) {
+ dev_err(dev, "failed to register PHY provider\n");
+ return PTR_ERR(provider);
+ }

PTR_ERR_OR_ZERO(phy_provider)?

Thanks
Kishon
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