Re: [PATCH v3 2/2] phy: add a driver for the Rockchip SoC internal PCIe PHY

[Kishon Vijay Abraham I]

Hi,

On Thursday 16 June 2016 06:52 AM, Shawn Lin wrote:
> This patch to add a generic PHY driver for rockchip PCIe PHY.
> Access the PHY via registers provided by GRF (general register
> files) module.
> 
> Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
> ---
> 
> Changes in v3: None
> Changes in v2: None
> 
>  drivers/phy/Kconfig             |   7 +
>  drivers/phy/Makefile            |   1 +
>  drivers/phy/phy-rockchip-pcie.c | 378 ++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 386 insertions(+)
>  create mode 100644 drivers/phy/phy-rockchip-pcie.c
> 
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index b869b98..d4fc293 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -361,6 +361,13 @@ config PHY_ROCKCHIP_DP
>  	help
>  	  Enable this to support the Rockchip Display Port PHY.
>  
> +config PHY_ROCKCHIP_PCIE
> +	tristate "Rockchip PCIe PHY Driver"
> +	depends on ARCH_ROCKCHIP && OF
> +	select GENERIC_PHY
> +	help
> +	  Enable this to support the Rockchip PCIe PHY.
> +
>  config PHY_ST_SPEAR1310_MIPHY
>  	tristate "ST SPEAR1310-MIPHY driver"
>  	select GENERIC_PHY
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index 9c3e73c..725e55d 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -39,6 +39,7 @@ obj-$(CONFIG_PHY_EXYNOS5_USBDRD)	+= phy-exynos5-usbdrd.o
>  obj-$(CONFIG_PHY_QCOM_APQ8064_SATA)	+= phy-qcom-apq8064-sata.o
>  obj-$(CONFIG_PHY_ROCKCHIP_USB) += phy-rockchip-usb.o
>  obj-$(CONFIG_PHY_ROCKCHIP_EMMC) += phy-rockchip-emmc.o
> +obj-$(CONFIG_PHY_ROCKCHIP_PCIE) += phy-rockchip-pcie.o
>  obj-$(CONFIG_PHY_ROCKCHIP_DP)		+= phy-rockchip-dp.o
>  obj-$(CONFIG_PHY_QCOM_IPQ806X_SATA)	+= phy-qcom-ipq806x-sata.o
>  obj-$(CONFIG_PHY_ST_SPEAR1310_MIPHY)	+= phy-spear1310-miphy.o
> diff --git a/drivers/phy/phy-rockchip-pcie.c b/drivers/phy/phy-rockchip-pcie.c
> new file mode 100644
> index 0000000..bc6cd17
> --- /dev/null
> +++ b/drivers/phy/phy-rockchip-pcie.c
> @@ -0,0 +1,378 @@
> +/*
> + * Rockchip PCIe PHY driver
> + *
> + * Copyright (C) 2016 Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
> + * 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/io.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_platform.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.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))
> +
> +#define PHY_MAX_LANE_NUM      4
> +#define PHY_CFG_DATA_SHIFT    7
> +#define PHY_CFG_ADDR_SHIFT    1
> +#define PHY_CFG_DATA_MASK     0xf
> +#define PHY_CFG_ADDR_MASK     0x3f
> +#define PHY_CFG_RD_MASK       0x3ff
> +#define PHY_CFG_WR_ENABLE     1
> +#define PHY_CFG_WR_DISABLE    1
> +#define PHY_CFG_WR_SHIFT      0
> +#define PHY_CFG_WR_MASK       1
> +#define PHY_CFG_PLL_LOCK      0x10
> +#define PHY_CFG_CLK_TEST      0x10
> +#define PHY_CFG_CLK_SCC       0x12
> +#define PHY_CFG_SEPE_RATE     BIT(3)
> +#define PHY_CFG_PLL_100M      BIT(3)
> +#define PHY_PLL_LOCKED        BIT(9)
> +#define PHY_PLL_OUTPUT        BIT(10)
> +#define PHY_LANE_A_STATUS     0x30
> +#define PHY_LANE_B_STATUS     0x31
> +#define PHY_LANE_C_STATUS     0x32
> +#define PHY_LANE_D_STATUS     0x33
> +#define PHY_LANE_RX_DET_SHIFT 11
> +#define PHY_LANE_RX_DET_TH    0x1
> +#define PHY_LANE_IDLE_OFF     0x1
> +#define PHY_LANE_IDLE_MASK    0x1
> +#define PHY_LANE_IDLE_A_SHIFT 3
> +#define PHY_LANE_IDLE_B_SHIFT 4
> +#define PHY_LANE_IDLE_C_SHIFT 5
> +#define PHY_LANE_IDLE_D_SHIFT 6
> +
> +struct rockchip_pcie_data {
> +	unsigned int pcie_conf;
> +	unsigned int pcie_status;
> +	unsigned int pcie_laneoff;
> +};
> +
> +struct rockchip_pcie_phy {
> +	struct rockchip_pcie_data *phy_data;
> +	struct regmap *reg_base;
> +	struct reset_control *phy_rst;
> +	struct clk *clk_pciephy_ref;
> +};
> +
> +static inline void phy_wr_cfg(struct rockchip_pcie_phy *rk_phy,
> +			      u32 addr, u32 data)
> +{
> +	regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,
> +		     HIWORD_UPDATE(data,
> +				   PHY_CFG_DATA_MASK,
> +				   PHY_CFG_DATA_SHIFT) |
> +		     HIWORD_UPDATE(addr,
> +				   PHY_CFG_ADDR_MASK,
> +				   PHY_CFG_ADDR_SHIFT));
> +	udelay(1);
> +	regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,
> +		     HIWORD_UPDATE(PHY_CFG_WR_ENABLE,
> +				   PHY_CFG_WR_MASK,
> +				   PHY_CFG_WR_SHIFT));
> +	udelay(1);
> +	regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,
> +		     HIWORD_UPDATE(PHY_CFG_WR_DISABLE,
> +				   PHY_CFG_WR_MASK,
> +				   PHY_CFG_WR_SHIFT));
> +}
> +
> +static inline u32 phy_rd_cfg(struct rockchip_pcie_phy *rk_phy,
> +			     u32 addr)
> +{
> +	u32 val;
> +
> +	regmap_write(rk_phy->reg_base, rk_phy->phy_data->pcie_conf,
> +		     HIWORD_UPDATE(addr,
> +				   PHY_CFG_RD_MASK,
> +				   PHY_CFG_ADDR_SHIFT));
> +	regmap_read(rk_phy->reg_base,
> +		    rk_phy->phy_data->pcie_status,
> +		    &val);
> +	return val;
> +}
> +
> +void rockchip_pcie_phy_laneoff(struct phy *phy)
> +{
> +	u32 status;
> +	struct rockchip_pcie_phy *rk_phy = phy_get_drvdata(phy);
> +	int i;
> +
> +	for (i = 0; i < PHY_MAX_LANE_NUM; i++) {
> +		status = phy_rd_cfg(rk_phy, PHY_LANE_A_STATUS + i);
> +		if (!((status >> PHY_LANE_RX_DET_SHIFT) &
> +		       PHY_LANE_RX_DET_TH))
> +			pr_debug("lane %d is used\n", i);
> +		else
> +			regmap_write(rk_phy->reg_base,
> +				     rk_phy->phy_data->pcie_laneoff,
> +				     HIWORD_UPDATE(PHY_LANE_IDLE_OFF,
> +						   PHY_LANE_IDLE_MASK,
> +						   PHY_LANE_IDLE_A_SHIFT + i));
> +	}
> +}
> +EXPORT_SYMBOL_GPL(rockchip_pcie_phy_laneoff);

Er.. don't use export symbols from phy driver. I think it would be nice if you
can model the driver in such a way that the PCIe driver can control individual
phy's.

Thanks
Kishon