Re: [RFC PATCH 2/2] phy: cadence: Add driver for Sierra PHY
From: Kishon Vijay Abraham I
Date: Mon Aug 20 2018 - 09:07:21 EST
Hi,
On Friday 17 August 2018 06:01 PM, Alan Douglas wrote:
> Add a Sierra PHY driver with PCIe and USB support.
> There are two resets to the PHY, one to enable
> the APB interface for programming registers, and
> another to enable the PHY itself.
>
> The sequence of operation on startup is to enable
> the APB bus, write the PHY registers and then
> enable the PHY.
>
> On power-down we simply put the PHY and APB bus in
> reset.
>
> Signed-off-by: Alan Douglas <adouglas@xxxxxxxxxxx>
> ---
> drivers/phy/Kconfig | 1 +
> drivers/phy/Makefile | 1 +
> drivers/phy/cadence/Kconfig | 9 ++
> drivers/phy/cadence/Makefile | 3 +
> drivers/phy/cadence/cdns-sierra.c | 326 ++++++++++++++++++++++++++++++++++++++
> 5 files changed, 340 insertions(+)
> create mode 100644 drivers/phy/cadence/Kconfig
> create mode 100644 drivers/phy/cadence/Makefile
> create mode 100644 drivers/phy/cadence/cdns-sierra.c
>
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index 5c8d452..cc47f85 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -43,6 +43,7 @@ config PHY_XGENE
> source "drivers/phy/allwinner/Kconfig"
> source "drivers/phy/amlogic/Kconfig"
> source "drivers/phy/broadcom/Kconfig"
> +source "drivers/phy/cadence/Kconfig"
> source "drivers/phy/hisilicon/Kconfig"
> source "drivers/phy/lantiq/Kconfig"
> source "drivers/phy/marvell/Kconfig"
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index 84e3bd9..ba48acd 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -15,6 +15,7 @@ obj-$(CONFIG_ARCH_RENESAS) += renesas/
> obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/
> obj-$(CONFIG_ARCH_TEGRA) += tegra/
> obj-y += broadcom/ \
> + cadence/ \
> hisilicon/ \
> marvell/ \
> motorola/ \
> diff --git a/drivers/phy/cadence/Kconfig b/drivers/phy/cadence/Kconfig
> new file mode 100644
> index 0000000..6bbe5a2
> --- /dev/null
> +++ b/drivers/phy/cadence/Kconfig
> @@ -0,0 +1,9 @@
> +#
> +# Phy drivers for cadence devices
> +#
> +config CDNS_SIERRA_PHY
> + tristate "CDNS Sierra PHY Driver"
> + depends on OF && HAS_IOMEM
depends on RESET_CONTROLLER?
> + select GENERIC_PHY
> + help
> + Enable this to support the Cadence Sierra PHY driver
> diff --git a/drivers/phy/cadence/Makefile b/drivers/phy/cadence/Makefile
> new file mode 100644
> index 0000000..b384cb3
> --- /dev/null
> +++ b/drivers/phy/cadence/Makefile
> @@ -0,0 +1,3 @@
> +# SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_CDNS_SIERRA_PHY) += cdns-sierra.o
> +
> diff --git a/drivers/phy/cadence/cdns-sierra.c b/drivers/phy/cadence/cdns-sierra.c
> new file mode 100644
> index 0000000..0581516
> --- /dev/null
> +++ b/drivers/phy/cadence/cdns-sierra.c
> @@ -0,0 +1,326 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Cadence Sierra PHY Driver
> + *
> + * Copyright (c) 2018 Cadence Design Systems
> + * Author: Alan Douglas <adouglas@xxxxxxxxxxx>
> + *
> + */
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include <linux/slab.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <dt-bindings/phy/phy.h>
> +
> +#define CDNS_PHY_PLL_CFG (0xc00e << 2)
> +#define CDNS_DET_STANDEC_A (0x4000 << 2)
> +#define CDNS_DET_STANDEC_B (0x4001 << 2)
> +#define CDNS_DET_STANDEC_C (0x4002 << 2)
> +#define CDNS_DET_STANDEC_D (0x4003 << 2)
> +#define CDNS_DET_STANDEC_E (0x4004 << 2)
> +#define CDNS_PSM_LANECAL (0x4008 << 2)
> +#define CDNS_PSM_DIAG (0x4015 << 2)
> +#define CDNS_PSC_TX_A0 (0x4028 << 2)
> +#define CDNS_PSC_TX_A1 (0x4029 << 2)
> +#define CDNS_PSC_TX_A2 (0x402A << 2)
> +#define CDNS_PSC_TX_A3 (0x402B << 2)
> +#define CDNS_PSC_RX_A0 (0x4030 << 2)
> +#define CDNS_PSC_RX_A1 (0x4031 << 2)
> +#define CDNS_PSC_RX_A2 (0x4032 << 2)
> +#define CDNS_PSC_RX_A3 (0x4033 << 2)
> +#define CDNS_PLLCTRL_SUBRATE (0x403A << 2)
> +#define CDNS_PLLCTRL_GEN_D (0x403E << 2)
> +#define CDNS_DRVCTRL_ATTEN (0x406A << 2)
> +#define CDNS_CLKPATHCTRL_TMR (0x4081 << 2)
> +#define CDNS_RX_CREQ_FLTR_A_MODE1 (0x4087 << 2)
> +#define CDNS_RX_CREQ_FLTR_A_MODE0 (0x4088 << 2)
> +#define CDNS_CREQ_CCLKDET_MODE01 (0x408E << 2)
> +#define CDNS_RX_CTLE_MAINTENANCE (0x4091 << 2)
> +#define CDNS_CREQ_FSMCLK_SEL (0x4092 << 2)
> +#define CDNS_CTLELUT_CTRL (0x4098 << 2)
> +#define CDNS_DFE_ECMP_RATESEL (0x40C0 << 2)
> +#define CDNS_DFE_SMP_RATESEL (0x40C1 << 2)
> +#define CDNS_DEQ_VGATUNE_CTRL (0x40E1 << 2)
> +#define CDNS_TMRVAL_MODE3 (0x416E << 2)
> +#define CDNS_TMRVAL_MODE2 (0x416F << 2)
> +#define CDNS_TMRVAL_MODE1 (0x4170 << 2)
> +#define CDNS_TMRVAL_MODE0 (0x4171 << 2)
> +#define CDNS_PICNT_MODE1 (0x4174 << 2)
> +#define CDNS_CPI_OUTBUF_RATESEL (0x417C << 2)
> +#define CDNS_LFPSFILT_NS (0x418A << 2)
> +#define CDNS_LFPSFILT_RD (0x418B << 2)
> +#define CDNS_LFPSFILT_MP (0x418C << 2)
> +#define CDNS_SDFILT_H2L_A (0x4191 << 2)
> +
> +#define SIERRA_PHYS_NUM 2
> +
> +struct cdns_phy_instance {
> + struct phy *phy;
> + u32 phy_type;
> + u32 nlanes;
> + void __iomem *base;
> +};
> +
> +struct cdns_sierra_phy {
> + struct device *dev;
> + void __iomem *base;
> + u32 *init_data;
> + struct cdns_phy_instance phys[SIERRA_PHYS_NUM];
> + struct reset_control *reset;
> + struct reset_control *apb_reset;
> + struct clk *clk;
> + struct phy *pcie_phy;
> +};
> +
> +static void cdns_sierra_pcie_on(struct cdns_phy_instance *ins)
> +{
> + int i;
> +
> + for (i = 0; i < (ins->nlanes << 11); i += (1 << 11)) {
> + writel(0x891f, ins->base + CDNS_DET_STANDEC_D + i);
> + writel(0x0053, ins->base + CDNS_DET_STANDEC_E + i);
> + writel(0x0400, ins->base + CDNS_TMRVAL_MODE2 + i);
> + writel(0x0200, ins->base + CDNS_TMRVAL_MODE3 + i);
> + }
> +}
> +
> +static void cdns_sierra_usb_on(struct cdns_phy_instance *ins)
> +{
> + int i;
> +
> + writel(0x0000, ins->base + CDNS_PHY_PLL_CFG);
> + for (i = 0; i < (ins->nlanes << 11); i += (1 << 11)) {
> + writel(0xFE0A, ins->base + CDNS_DET_STANDEC_A + i);
> + writel(0x000F, ins->base + CDNS_DET_STANDEC_B + i);
> + writel(0x55A5, ins->base + CDNS_DET_STANDEC_C + i);
> + writel(0x69AD, ins->base + CDNS_DET_STANDEC_D + i);
> + writel(0x0241, ins->base + CDNS_DET_STANDEC_E + i);
> + writel(0x0110, ins->base + CDNS_PSM_LANECAL + i);
> + writel(0xCF00, ins->base + CDNS_PSM_DIAG + i);
> + writel(0x001F, ins->base + CDNS_PSC_TX_A0 + i);
> + writel(0x0007, ins->base + CDNS_PSC_TX_A1 + i);
> + writel(0x0003, ins->base + CDNS_PSC_TX_A2 + i);
> + writel(0x0003, ins->base + CDNS_PSC_TX_A3 + i);
> + writel(0x0FFF, ins->base + CDNS_PSC_RX_A0 + i);
> + writel(0x0003, ins->base + CDNS_PSC_RX_A1 + i);
> + writel(0x0003, ins->base + CDNS_PSC_RX_A2 + i);
> + writel(0x0001, ins->base + CDNS_PSC_RX_A3 + i);
> + writel(0x0001, ins->base + CDNS_PLLCTRL_SUBRATE + i);
> + writel(0x0406, ins->base + CDNS_PLLCTRL_GEN_D + i);
> + writel(0x0000, ins->base + CDNS_DRVCTRL_ATTEN + i);
> + writel(0x823E, ins->base + CDNS_CLKPATHCTRL_TMR + i);
> + writel(0x078F, ins->base + CDNS_RX_CREQ_FLTR_A_MODE1 + i);
> + writel(0x078F, ins->base + CDNS_RX_CREQ_FLTR_A_MODE0 + i);
> + writel(0x7B3C, ins->base + CDNS_CREQ_CCLKDET_MODE01 + i);
> + writel(0x023C, ins->base + CDNS_RX_CTLE_MAINTENANCE + i);
> + writel(0x3232, ins->base + CDNS_CREQ_FSMCLK_SEL + i);
> + writel(0x8452, ins->base + CDNS_CTLELUT_CTRL + i);
> + writel(0x4121, ins->base + CDNS_DFE_ECMP_RATESEL + i);
> + writel(0x4121, ins->base + CDNS_DFE_SMP_RATESEL + i);
> + writel(0x9999, ins->base + CDNS_DEQ_VGATUNE_CTRL + i);
> + writel(0x0330, ins->base + CDNS_TMRVAL_MODE0 + i);
> + writel(0x01FF, ins->base + CDNS_PICNT_MODE1 + i);
> + writel(0x0009, ins->base + CDNS_CPI_OUTBUF_RATESEL + i);
> + writel(0x000F, ins->base + CDNS_LFPSFILT_NS + i);
> + writel(0x0009, ins->base + CDNS_LFPSFILT_RD + i);
> + writel(0x0001, ins->base + CDNS_LFPSFILT_MP + i);
> + writel(0x8013, ins->base + CDNS_SDFILT_H2L_A + i);
> + writel(0x0400, ins->base + CDNS_TMRVAL_MODE1 + i);
Are these tuning parameters? Don't they change for different platforms/vendors?
> + }
> +}
> +
> +static int cdns_sierra_phy_on(struct phy *x)
> +{
> + struct cdns_phy_instance *ins = phy_get_drvdata(x);
> + struct cdns_sierra_phy *phy = dev_get_drvdata(x->dev.parent);
> + int ret;
> +
> + ret = clk_prepare_enable(phy->clk);
> + if (ret)
> + return ret;
> +
> + /* Ensure the PHY is in reset */
> + reset_control_assert(phy->reset);
> +
> + /* Enable APB */
> + reset_control_deassert(phy->apb_reset);
> +
> + /* Program the PHY registers*/
> + if (ins->phy_type == PHY_TYPE_PCIE)
> + cdns_sierra_pcie_on(ins);
> + else
> + cdns_sierra_usb_on(ins);
> +
> + /* Take the PHY out of reset */
> + ret = reset_control_assert(phy->reset);
> +
> + if (ret) {
> + clk_disable_unprepare(phy->clk);
> + return ret;
> + }
> +
> + return ret;
> +}
> +
> +static int cdns_sierra_phy_off(struct phy *x)
> +{
> + struct cdns_sierra_phy *phy = dev_get_drvdata(x->dev.parent);
> + int ret = 0;
> +
> + reset_control_assert(phy->reset);
> + reset_control_assert(phy->apb_reset);
> + clk_disable_unprepare(phy->clk);
> + dev_info(phy->dev, "sierra PHY OFF\n");
dev_vdbg?
> +
> + return ret;
> +}
> +
> +static const struct phy_ops ops = {
> + .power_on = cdns_sierra_phy_on,
> + .power_off = cdns_sierra_phy_off,
> + .owner = THIS_MODULE,
> +};
> +
> +static const struct of_device_id cdns_sierra_id_table[];
> +static struct phy *cdns_sierra_xlate(struct device *dev,
> + struct of_phandle_args *args)
> +{
> + struct cdns_sierra_phy *sphy = dev_get_drvdata(dev);
> + struct cdns_phy_instance *ins = NULL;
> + int i;
> +
> + if (args->args_count != 2) {
> + dev_err(dev, "invalid number of cells in 'phy' property\n");
> + return ERR_PTR(-EINVAL);
> + }
> +
> + if (WARN_ON(args->args[1] == 0 || args->args[1] > 4))
> + return ERR_PTR(-ENODEV);
> +
> + for (i = 0; i < SIERRA_PHYS_NUM; i++) {
> + if (sphy->phys[i].phy_type == args->args[0])
> + ins = &sphy->phys[i];
> + }
> +
> + if (!ins) {
> + dev_err(dev, "failed to find appropriate phy\n");
> + return ERR_PTR(-EINVAL);
> + }
> +
> + ins->nlanes = args->args[1];
> +
> + return ins->phy;
> +}
> +
> +static int cdns_sierra_phy_probe(struct platform_device *pdev)
> +{
> + struct cdns_sierra_phy *sphy;
> + struct phy_provider *phy_provider;
> + struct device *dev = &pdev->dev;
> + const struct of_device_id *match;
> + struct resource *res;
> + int i;
> +
> + sphy = devm_kzalloc(dev, sizeof(*sphy), GFP_KERNEL);
> + if (!sphy)
> + return -ENOMEM;
> +
> + sphy->dev = dev;
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "reg");
> + sphy->base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(sphy->base)) {
> + dev_err(dev, "missing \"reg\"\n");
> + return PTR_ERR(sphy->base);
> + }
> +
> + /* Get init data for this PHY */
> + match = of_match_device(cdns_sierra_id_table, dev);
> + if (!match)
> + return -EINVAL;
> + sphy->init_data = (u32 *)match->data;
> +
> + /* Check that PHY is present */
> + if (sphy->init_data[0] != readl(sphy->base))
> + return -EINVAL;
> +
> + platform_set_drvdata(pdev, sphy);
> +
> + sphy->clk = devm_clk_get(dev, "phy_clk");
> + if (IS_ERR(sphy->clk)) {
> + dev_err(dev, "failed to get clock phy_clk\n");
> + return PTR_ERR(sphy->clk);
> + }
> +
> + sphy->reset = devm_reset_control_get(dev, "sierra_reset");
> + if (IS_ERR(sphy->reset)) {
> + dev_err(dev, "failed to get reset\n");
> + return PTR_ERR(sphy->reset);
> + }
> +
> + sphy->apb_reset = devm_reset_control_get(dev, "sierra_apb");
> + if (IS_ERR(sphy->apb_reset)) {
> + dev_err(dev, "failed to get apb reset\n");
> + return PTR_ERR(sphy->apb_reset);
> + }
> +
> + sphy->phys[0].phy_type = PHY_TYPE_PCIE;
> + sphy->phys[1].phy_type = PHY_TYPE_USB3;
We can have two subnodes, one for PCIe PHY and one for USB3 PHY. That way we
don't create two PHY's if a vendor hasn't exposed one type of PHY. We also
don't need a custom xlate then.
Thanks
Kishon