| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <20201208092440.GD20575@bogon.m.sigxcpu.org>
Date: Tue, 8 Dec 2020 10:24:40 +0100
From: Guido Günther <guido.gunther@...i.sm>
To: Liu Ying <victor.liu@....com>
Cc: linux-kernel@...r.kernel.org, devicetree@...r.kernel.org,
dri-devel@...ts.freedesktop.org,
linux-arm-kernel@...ts.infradead.org, kishon@...com,
vkoul@...nel.org, robh+dt@...nel.org, a.hajda@...sung.com,
narmstrong@...libre.com, Laurent.pinchart@...asonboard.com,
jonas@...boo.se, jernej.skrabec@...l.net, airlied@...ux.ie,
daniel@...ll.ch, shawnguo@...nel.org, s.hauer@...gutronix.de,
kernel@...gutronix.de, festevam@...il.com, linux-imx@....com,
robert.chiras@....com, martin.kepplinger@...i.sm
Subject: Re: [PATCH 4/4] phy: freescale: phy-fsl-imx8-mipi-dphy: Add i.MX8qxp
LVDS PHY mode support
Hi Liu,
some minor comments inline:
On Fri, Dec 04, 2020 at 03:33:44PM +0800, Liu Ying wrote:
> i.MX8qxp SoC embeds a Mixel MIPI DPHY + LVDS PHY combo which supports
> either a MIPI DSI display or a LVDS display. The PHY mode is controlled
> by SCU firmware and the driver would call a SCU firmware function to
> configure the PHY mode. The single LVDS PHY has 4 data lanes to support
> a LVDS display. Also, with a master LVDS PHY and a slave LVDS PHY, they
> may work together to support a LVDS display with 8 data lanes(usually, dual
> LVDS link display). Note that this patch supports the LVDS PHY mode only
> for the i.MX8qxp Mixel combo PHY, i.e., the MIPI DPHY mode is yet to be
> supported, so for now error would be returned from ->set_mode() if MIPI
> DPHY mode is passed over to it for the combo PHY.
>
> Cc: Guido Günther <agx@...xcpu.org>
> Cc: Robert Chiras <robert.chiras@....com>
> Cc: Kishon Vijay Abraham I <kishon@...com>
> Cc: Vinod Koul <vkoul@...nel.org>
> Cc: Shawn Guo <shawnguo@...nel.org>
> Cc: Sascha Hauer <s.hauer@...gutronix.de>
> Cc: Pengutronix Kernel Team <kernel@...gutronix.de>
> Cc: Fabio Estevam <festevam@...il.com>
> Cc: NXP Linux Team <linux-imx@....com>
> Signed-off-by: Liu Ying <victor.liu@....com>
> ---
> drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c | 266 ++++++++++++++++++++++++-
> 1 file changed, 255 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c b/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> index a95572b..37084a9 100644
> --- a/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> @@ -4,17 +4,31 @@
> * Copyright 2019 Purism SPC
> */
>
> +#include <linux/bitfield.h>
> #include <linux/clk.h>
> #include <linux/clk-provider.h>
> #include <linux/delay.h>
> +#include <linux/firmware/imx/ipc.h>
> +#include <linux/firmware/imx/svc/misc.h>
> #include <linux/io.h>
> #include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
> #include <linux/module.h>
> #include <linux/of.h>
> #include <linux/of_platform.h>
> #include <linux/phy/phy.h>
> #include <linux/platform_device.h>
> #include <linux/regmap.h>
> +#include <dt-bindings/firmware/imx/rsrc.h>
> +
> +/* Control and Status Registers(CSR) */
> +#define PHY_CTRL 0x00
> +#define CCM_MASK GENMASK(7, 5)
> +#define CCM(n) FIELD_PREP(CCM_MASK, (n))
> +#define CA_MASK GENMASK(4, 2)
> +#define CA(n) FIELD_PREP(CA_MASK, (n))
> +#define RFB BIT(1)
> +#define LVDS_EN BIT(0)
>
> /* DPHY registers */
> #define DPHY_PD_DPHY 0x00
> @@ -55,8 +69,15 @@
> #define PWR_ON 0
> #define PWR_OFF 1
>
> +#define MIN_VCO_FREQ 640000000
> +#define MAX_VCO_FREQ 1500000000
> +
> +#define MIN_LVDS_REFCLK_FREQ 24000000
> +#define MAX_LVDS_REFCLK_FREQ 150000000
> +
> enum mixel_dphy_devtype {
> MIXEL_IMX8MQ,
> + MIXEL_IMX8QXP,
> };
>
> struct mixel_dphy_devdata {
> @@ -65,6 +86,7 @@ struct mixel_dphy_devdata {
> u8 reg_rxlprp;
> u8 reg_rxcdrp;
> u8 reg_rxhs_settle;
> + bool is_combo; /* MIPI DPHY and LVDS PHY combo */
> };
>
> static const struct mixel_dphy_devdata mixel_dphy_devdata[] = {
> @@ -74,6 +96,10 @@ static const struct mixel_dphy_devdata mixel_dphy_devdata[] = {
> .reg_rxlprp = 0x40,
> .reg_rxcdrp = 0x44,
> .reg_rxhs_settle = 0x48,
> + .is_combo = false,
> + },
> + [MIXEL_IMX8QXP] = {
> + .is_combo = true,
> },
> };
>
> @@ -95,8 +121,12 @@ struct mixel_dphy_cfg {
> struct mixel_dphy_priv {
> struct mixel_dphy_cfg cfg;
> struct regmap *regmap;
> + struct regmap *lvds_regmap;
> struct clk *phy_ref_clk;
> const struct mixel_dphy_devdata *devdata;
> + struct imx_sc_ipc *ipc_handle;
> + bool is_slave;
> + int id;
> };
>
> static const struct regmap_config mixel_dphy_regmap_config = {
> @@ -317,7 +347,8 @@ static int mixel_dphy_set_pll_params(struct phy *phy)
> return 0;
> }
>
> -static int mixel_dphy_configure(struct phy *phy, union phy_configure_opts *opts)
> +static int
> +mixel_dphy_configure_mipi_dphy(struct phy *phy, union phy_configure_opts *opts)
> {
> struct mixel_dphy_priv *priv = phy_get_drvdata(phy);
> struct mixel_dphy_cfg cfg = { 0 };
> @@ -345,15 +376,118 @@ static int mixel_dphy_configure(struct phy *phy, union phy_configure_opts *opts)
> return 0;
> }
>
> +static int
> +mixel_dphy_configure_lvds_phy(struct phy *phy, union phy_configure_opts *opts)
> +{
> + struct mixel_dphy_priv *priv = phy_get_drvdata(phy);
> + struct phy_configure_opts_lvds *lvds_opts = &opts->lvds;
> + unsigned long data_rate;
> + unsigned long fvco;
> + u32 rsc;
> + u32 co;
> + int ret;
> +
> + priv->is_slave = lvds_opts->is_slave;
> +
> + /* LVDS interface pins */
> + regmap_write(priv->lvds_regmap, PHY_CTRL, CCM(0x5) | CA(0x4) | RFB);
> +
> + /* enable MODE8 only for slave LVDS PHY */
> + rsc = priv->id ? IMX_SC_R_MIPI_1 : IMX_SC_R_MIPI_0;
> + ret = imx_sc_misc_set_control(priv->ipc_handle, rsc, IMX_SC_C_DUAL_MODE,
> + lvds_opts->is_slave);
> + if (ret) {
> + dev_err(&phy->dev, "Failed to configure MODE8: %d\n", ret);
> + return ret;
> + }
> +
> + /*
> + * Choose an appropriate divider ratio to meet the requirement of
> + * PLL VCO frequency range.
> + *
> + * ----- 640MHz ~ 1500MHz ------------ ---------------
> + * | VCO | ----------------> | CO divider | -> | LVDS data rate|
> + * ----- FVCO ------------ ---------------
> + * 1/2/4/8 div 7 * differential_clk_rate
> + */
> + data_rate = 7 * lvds_opts->differential_clk_rate;
> + for (co = 1; co <= 8; co *= 2) {
> + fvco = data_rate * co;
> +
> + if (fvco >= MIN_VCO_FREQ)
> + break;
> + }
> +
> + if (fvco < MIN_VCO_FREQ || fvco > MAX_VCO_FREQ) {
> + dev_err(&phy->dev, "VCO frequency %lu is out of range\n", fvco);
> + return -ERANGE;
> + }
> +
> + /*
> + * CO is configurable, while CN and CM are not,
> + * as fixed ratios 1 and 7 are applied respectively.
> + */
> + phy_write(phy, __ffs(co), DPHY_CO);
> +
> + /* set reference clock rate */
> + clk_set_rate(priv->phy_ref_clk, lvds_opts->differential_clk_rate);
> +
> + return ret;
> +}
> +
> +static int mixel_dphy_configure(struct phy *phy, union phy_configure_opts *opts)
> +{
> + if (phy->attrs.mode == PHY_MODE_MIPI_DPHY)
> + return mixel_dphy_configure_mipi_dphy(phy, opts);
> + else if (phy->attrs.mode == PHY_MODE_LVDS)
> + return mixel_dphy_configure_lvds_phy(phy, opts);
> +
> + dev_err(&phy->dev, "Failed to configure PHY with invalid PHY mode\n");
> + return -EINVAL;
> +}
> +
> +static int
> +mixel_dphy_validate_lvds_phy(struct phy *phy, union phy_configure_opts *opts)
> +{
> + struct phy_configure_opts_lvds *lvds_cfg = &opts->lvds;
> +
> + if (lvds_cfg->bits_per_lane_and_dclk_cycle != 7) {
> + dev_err(&phy->dev, "Invalid bits per LVDS data lane: %u\n",
> + lvds_cfg->bits_per_lane_and_dclk_cycle);
> + return -EINVAL;
> + }
> +
> + if (lvds_cfg->lanes != 4) {
> + dev_err(&phy->dev, "Invalid LVDS data lanes: %u\n",
> + lvds_cfg->lanes);
> + return -EINVAL;
> + }
> +
> + if (lvds_cfg->differential_clk_rate < MIN_LVDS_REFCLK_FREQ ||
> + lvds_cfg->differential_clk_rate > MAX_LVDS_REFCLK_FREQ) {
> + dev_err(&phy->dev,
> + "Invalid LVDS differential clock rate: %lu\n",
> + lvds_cfg->differential_clk_rate);
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> static int mixel_dphy_validate(struct phy *phy, enum phy_mode mode, int submode,
> union phy_configure_opts *opts)
> {
> - struct mixel_dphy_cfg cfg = { 0 };
> + if (mode == PHY_MODE_MIPI_DPHY) {
> + struct mixel_dphy_cfg mipi_dphy_cfg = { 0 };
>
> - if (mode != PHY_MODE_MIPI_DPHY)
> - return -EINVAL;
> + return mixel_dphy_config_from_opts(phy, &opts->mipi_dphy,
> + &mipi_dphy_cfg);
> + } else if (mode == PHY_MODE_LVDS) {
> + return mixel_dphy_validate_lvds_phy(phy, opts);
> + }
>
> - return mixel_dphy_config_from_opts(phy, &opts->mipi_dphy, &cfg);
> + dev_err(&phy->dev, "Failed to validate PHY with invalid PHY mode\n");
Can you print the `mode` here so it becomes obvious from the error what
incorrect mode got passed in?
> + return -EINVAL;
> }
>
> static int mixel_dphy_init(struct phy *phy)
> @@ -373,27 +507,74 @@ static int mixel_dphy_exit(struct phy *phy)
> return 0;
> }
>
> -static int mixel_dphy_power_on(struct phy *phy)
> +static int mixel_dphy_power_on_mipi_dphy(struct phy *phy)
> {
> struct mixel_dphy_priv *priv = phy_get_drvdata(phy);
> u32 locked;
> int ret;
>
> - ret = clk_prepare_enable(priv->phy_ref_clk);
> - if (ret < 0)
> - return ret;
> -
> phy_write(phy, PWR_ON, DPHY_PD_PLL);
> ret = regmap_read_poll_timeout(priv->regmap, DPHY_LOCK, locked,
> locked, PLL_LOCK_SLEEP,
> PLL_LOCK_TIMEOUT);
> if (ret < 0) {
> dev_err(&phy->dev, "Could not get DPHY lock (%d)!\n", ret);
> - goto clock_disable;
> + return ret;
> }
> phy_write(phy, PWR_ON, DPHY_PD_DPHY);
>
> return 0;
> +}
> +
> +static int mixel_dphy_power_on_lvds_phy(struct phy *phy)
> +{
> + struct mixel_dphy_priv *priv = phy_get_drvdata(phy);
> + u32 locked;
> + int ret;
> +
> + regmap_update_bits(priv->lvds_regmap, PHY_CTRL, LVDS_EN, LVDS_EN);
> +
> + phy_write(phy, PWR_ON, DPHY_PD_DPHY);
> + phy_write(phy, PWR_ON, DPHY_PD_PLL);
> +
> + /* do not wait for slave LVDS PHY being locked */
> + if (priv->is_slave)
> + return 0;
> +
> + ret = regmap_read_poll_timeout(priv->regmap, DPHY_LOCK, locked,
> + locked, PLL_LOCK_SLEEP,
> + PLL_LOCK_TIMEOUT);
> + if (ret < 0) {
> + dev_err(&phy->dev, "Could not get LVDS PHY lock (%d)!\n", ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int mixel_dphy_power_on(struct phy *phy)
> +{
> + struct mixel_dphy_priv *priv = phy_get_drvdata(phy);
> + int ret;
> +
> + ret = clk_prepare_enable(priv->phy_ref_clk);
> + if (ret < 0)
> + return ret;
> +
> + if (phy->attrs.mode == PHY_MODE_MIPI_DPHY) {
> + ret = mixel_dphy_power_on_mipi_dphy(phy);
> + } else if (phy->attrs.mode == PHY_MODE_LVDS) {
> + ret = mixel_dphy_power_on_lvds_phy(phy);
> + } else {
> + dev_err(&phy->dev,
> + "Failed to power on PHY with invalid PHY mode\n");
Can you print the `mode` here so it becomes obvious from the error what
incorrect mode got passed in?
> + ret = -EINVAL;
> + }
> +
> + if (ret)
> + goto clock_disable;
> +
> + return 0;
> clock_disable:
> clk_disable_unprepare(priv->phy_ref_clk);
> return ret;
> @@ -406,16 +587,52 @@ static int mixel_dphy_power_off(struct phy *phy)
> phy_write(phy, PWR_OFF, DPHY_PD_PLL);
> phy_write(phy, PWR_OFF, DPHY_PD_DPHY);
>
> + if (phy->attrs.mode == PHY_MODE_LVDS)
> + regmap_update_bits(priv->lvds_regmap, PHY_CTRL, LVDS_EN, 0);
> +
> clk_disable_unprepare(priv->phy_ref_clk);
>
> return 0;
> }
>
> +static int mixel_dphy_set_mode(struct phy *phy, enum phy_mode mode, int submode)
> +{
> + struct mixel_dphy_priv *priv = phy_get_drvdata(phy);
> + int ret;
> +
I'd reject all modes except PHY_MODE_MIPI_DPHY and PHY_MODE_MIPI_LVDS upfront...
> + /* Currently, MIPI DPHY mode only, if it's not a combo PHY. */
> + if (!priv->devdata->is_combo && mode != PHY_MODE_MIPI_DPHY) {
> + dev_err(&phy->dev, "Failed to set PHY mode to MIPI DPHY\n");
> + return -EINVAL;
> + }
> +
> + if (priv->devdata->is_combo && mode != PHY_MODE_LVDS) {
> + dev_err(&phy->dev, "Failed to set PHY mode for combo PHY\n");
> + return -EINVAL;
> + }
...and then just reject on whetehr `is_combo` is set or not. This makes
it easier to add more later.
> + if (priv->devdata->is_combo) {
> + u32 rsc = priv->id ? IMX_SC_R_MIPI_1 : IMX_SC_R_MIPI_0;
> +
> + ret = imx_sc_misc_set_control(priv->ipc_handle,
> + rsc, IMX_SC_C_MODE,
> + mode == PHY_MODE_LVDS);
> + if (ret) {
> + dev_err(&phy->dev,
> + "Failed to set PHY mode via SCU ipc: %d\n", ret);
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +
> static const struct phy_ops mixel_dphy_phy_ops = {
> .init = mixel_dphy_init,
> .exit = mixel_dphy_exit,
> .power_on = mixel_dphy_power_on,
> .power_off = mixel_dphy_power_off,
> + .set_mode = mixel_dphy_set_mode,
> .configure = mixel_dphy_configure,
> .validate = mixel_dphy_validate,
> .owner = THIS_MODULE,
> @@ -424,6 +641,8 @@ static const struct phy_ops mixel_dphy_phy_ops = {
> static const struct of_device_id mixel_dphy_of_match[] = {
> { .compatible = "fsl,imx8mq-mipi-dphy",
> .data = &mixel_dphy_devdata[MIXEL_IMX8MQ] },
> + { .compatible = "fsl,imx8qxp-mipi-dphy",
> + .data = &mixel_dphy_devdata[MIXEL_IMX8QXP] },
> { /* sentinel */ },
> };
> MODULE_DEVICE_TABLE(of, mixel_dphy_of_match);
> @@ -436,6 +655,7 @@ static int mixel_dphy_probe(struct platform_device *pdev)
> struct mixel_dphy_priv *priv;
> struct phy *phy;
> void __iomem *base;
> + int ret;
>
> if (!np)
> return -ENODEV;
> @@ -467,6 +687,30 @@ static int mixel_dphy_probe(struct platform_device *pdev)
> dev_dbg(dev, "phy_ref clock rate: %lu\n",
> clk_get_rate(priv->phy_ref_clk));
>
> + if (priv->devdata->is_combo) {
> + priv->lvds_regmap =
> + syscon_regmap_lookup_by_phandle(np, "fsl,syscon");
> + if (IS_ERR(priv->lvds_regmap)) {
> + ret = PTR_ERR(priv->lvds_regmap);
> + dev_err_probe(dev, ret, "Failed to get LVDS regmap\n");
> + return ret;
> + }
> +
> + priv->id = of_alias_get_id(np, "mipi_dphy");
> + if (priv->id < 0) {
> + dev_err(dev, "Failed to get phy node alias id: %d\n",
> + priv->id);
> + return priv->id;
> + }
> +
> + ret = imx_scu_get_handle(&priv->ipc_handle);
> + if (ret) {
> + dev_err_probe(dev, ret,
> + "Failed to get SCU ipc handle\n");
> + return ret;
> + }
> + }
> +
> dev_set_drvdata(dev, priv);
>
> phy = devm_phy_create(dev, np, &mixel_dphy_phy_ops);
> --
> 2.7.4
>
Cheers,
-- Guido
Powered by blists - more mailing lists