Re: [PATCH v3 2/2] phy: cygnus: pcie: Add Cygnus PCIe PHY support
From: Ray Jui
Date: Fri Sep 18 2015 - 19:55:50 EST
On 9/17/2015 11:22 PM, Kishon Vijay Abraham I wrote:
> Hi,
>
> On Tuesday 15 September 2015 11:26 PM, Ray Jui wrote:
>> This patch adds the PCIe PHY support for the Broadcom PCIe RC interface
>> on Cygnus
>>
>> 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 | 9 ++
>> drivers/phy/Makefile | 1 +
>> drivers/phy/phy-bcm-cygnus-pcie.c | 198 ++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 208 insertions(+)
>> create mode 100644 drivers/phy/phy-bcm-cygnus-pcie.c
>>
>> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
>> index 47da573..947bae2 100644
>> --- a/drivers/phy/Kconfig
>> +++ b/drivers/phy/Kconfig
>> @@ -371,4 +371,13 @@ config PHY_BRCMSTB_SATA
>> Enable this to support the SATA3 PHY on 28nm Broadcom STB SoCs.
>> Likely useful only with CONFIG_SATA_BRCMSTB enabled.
>>
>> +config PHY_CYGNUS_PCIE
>> + tristate "Broadcom Cygnus PCIe PHY driver"
>> + depends on OF && (ARCH_BCM_CYGNUS || COMPILE_TEST)
>> + select GENERIC_PHY
>> + default ARCH_BCM_CYGNUS
>> + help
>> + Enable this to support the Broadcom Cygnus PCIe PHY.
>> + If unsure, say N.
>> +
>> endmenu
>> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
>> index a5b18c1..fdce78d 100644
>> --- a/drivers/phy/Makefile
>> +++ b/drivers/phy/Makefile
>> @@ -46,3 +46,4 @@ obj-$(CONFIG_PHY_QCOM_UFS) += phy-qcom-ufs-qmp-14nm.o
>> obj-$(CONFIG_PHY_TUSB1210) += phy-tusb1210.o
>> obj-$(CONFIG_PHY_BRCMSTB_SATA) += phy-brcmstb-sata.o
>> obj-$(CONFIG_PHY_PISTACHIO_USB) += phy-pistachio-usb.o
>> +obj-$(CONFIG_PHY_CYGNUS_PCIE) += phy-bcm-cygnus-pcie.o
>> diff --git a/drivers/phy/phy-bcm-cygnus-pcie.c b/drivers/phy/phy-bcm-cygnus-pcie.c
>> new file mode 100644
>> index 0000000..0fb6750
>> --- /dev/null
>> +++ b/drivers/phy/phy-bcm-cygnus-pcie.c
>> @@ -0,0 +1,198 @@
>> +/*
>> + * 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>
>> +
>> +#define PCIE_CFG_OFFSET 0x00
>> +#define PCIE1_PHY_IDDQ_SHIFT 10
>> +#define 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
>> + * @phy: pointer to the kernel PHY device
>> + */
>> +struct cygnus_pcie_phy {
>> + struct cygnus_pcie_phy_core *core;
>> + enum cygnus_pcie_phy_id id;
>> + struct phy *phy;
>> +};
>> +
>> +/**
>> + * struct cygnus_pcie_phy_core - Cygnus PCIe PHY core control
>> + * @dev: pointer to device
>> + * @base: base register
>> + * @lock: mutex to protect access to individual PHYs
>> + * @phys: pointer to Cygnus PHY device
>> + */
>> +struct cygnus_pcie_phy_core {
>> + struct device *dev;
>> + void __iomem *base;
>> + struct mutex lock;
>> + struct cygnus_pcie_phy phys[MAX_NUM_PHYS];
>> +};
>> +
>> +static int cygnus_pcie_power_config(struct cygnus_pcie_phy *phy, bool enable)
>> +{
>> + struct cygnus_pcie_phy_core *core = phy->core;
>> + unsigned shift;
>> + u32 val;
>> +
>> + mutex_lock(&core->lock);
>> +
>> + switch (phy->id) {
>> + case CYGNUS_PHY_PCIE0:
>> + shift = PCIE0_PHY_IDDQ_SHIFT;
>> + break;
>> +
>> + case CYGNUS_PHY_PCIE1:
>> + shift = PCIE1_PHY_IDDQ_SHIFT;
>> + break;
>> +
>> + default:
>> + mutex_unlock(&core->lock);
>> + dev_err(core->dev, "PCIe PHY id%d invalid\n", phy->id);
>> + return -EINVAL;
>> + }
>> +
>> + if (enable) {
>> + val = readl(core->base + PCIE_CFG_OFFSET);
>> + val &= ~BIT(shift);
>> + writel(val, core->base + PCIE_CFG_OFFSET);
>> + msleep(50);
>> + } else {
>> + val = readl(core->base + PCIE_CFG_OFFSET);
>> + val |= BIT(shift);
>> + writel(val, core->base + PCIE_CFG_OFFSET);
>> + }
>> +
>> + mutex_unlock(&core->lock);
>> + dev_info(core->dev, "PCIe PHY %s\n", enable ? "enabled" : "disabled");
>> + return 0;
>> +}
>> +
>> +static int cygnus_pcie_phy_power_on(struct phy *p)
>> +{
>> + struct cygnus_pcie_phy *phy = phy_get_drvdata(p);
>> +
>> + return cygnus_pcie_power_config(phy, true);
>> +}
>> +
>> +static int cygnus_pcie_phy_power_off(struct phy *p)
>> +{
>> + struct cygnus_pcie_phy *phy = phy_get_drvdata(p);
>> +
>> + return cygnus_pcie_power_config(phy, false);
>> +}
>> +
>> +static struct phy_ops cygnus_pcie_phy_ops = {
>> + .power_on = cygnus_pcie_phy_power_on,
>> + .power_off = cygnus_pcie_phy_power_off,
>
> .owner is required here.
Okay will add that.
>> +};
>> +
>> +static struct phy *cygnus_pcie_phy_xlate(struct device *dev,
>> + struct of_phandle_args *args)
>> +{
>> + struct cygnus_pcie_phy_core *core;
>> + int id;
>> +
>> + core = dev_get_drvdata(dev);
>> + if (!core)
>> + return ERR_PTR(-EINVAL);
>> +
>> + id = args->args[0];
>> +
>> + if (WARN_ON(id >= MAX_NUM_PHYS))
>> + return ERR_PTR(-ENODEV);
>> +
>> + 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->base = devm_ioremap_resource(dev, res);
>> + if (IS_ERR(core->base))
>> + return PTR_ERR(core->base);
>> +
>> + mutex_init(&core->lock);
>> +
>> + for (i = 0; i < MAX_NUM_PHYS; i++) {
>
> Don't have to hard code MAX_NUM_PHYS. This can be modelled in dt itself.
> Create a single PHY provider node and model each individual PHYs as the
> child node of the PHY provider.
Ok. I'll make the change. Note MAX_NUM_PHYS will stay, just to check
against the max number of PCIe PHYs that can be supported. But each
individual PHY will be modeled by a child node, and #phy-cells become zero.
>> + 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);
>
> this custom xlate function is not required at all.
Yes, now #phy-cells is zero, I can use of_phy_simple_xlate.
>
> Thanks
> Kishon
>
Thanks,
Ray
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