NACK/Cmnt: [PATCH 1/2] UBUNTU: SAUCE: phy: qcom: edp: split power-on sequencing by PHY version

Tobias Heider tobias.heider at canonical.com
Thu Sep 17 14:17:52 UTC 2026


Sorry I fumbled the mail, I originally forgot to include those two in
the series I sent yesterday.
They would be quite helpful since they make some OEM laptops work with
26.10 and increase our testing capacity.

I'll resend them with a source, cover letter and subject.

On Thu, Sep 17, 2026 at 12:38 PM Stefan Bader
<stefan.bader at canonical.com> wrote:
>
> On 17/09/2026 11:43, Tobias Heider via kernel-team wrote:
> > From: Bjorn Andersson <bjorn.andersson at oss.qualcomm.com>
> >
> > BugLink: https://bugs.launchpad.net/bugs/2167217
> >
> > The eDP PHY power-on sequence has grown version-specific differences,
> > but qcom_edp_phy_power_on() still contains the sequence as one shared
> > flow. This makes it difficult to add newer PHY programming without
> > interleaving it with the v4/v6 sequence.
> >
> > Split the power-on sequence into version callbacks for the parts that
> > differ between PHY revisions:
> >
> >    - pre-power-on preparation
> >    - TX programming before PLL enable
> >    - rate/PCS programming
> >    - lane programming after PLL enable
> >    - final status polling
> >
> > Keep the existing v4/v6 sequence as the v46 implementation, and wire v8
> > to the same callbacks for now. This keeps the programming unchanged
> > while making the next patch a v8-only programming update.
> >
> > Assisted-by: Codex:GPT-5.5
> > Signed-off-by: Bjorn Andersson <bjorn.andersson at oss.qualcomm.com>
> > Reviewed-by: Konrad Dybcio <konrad.dybcio at oss.qualcomm.com>
> > Signed-off-by: Tobias Heider <tobias.heider at canonical.com>
> > ---
>
>
> Rejected for the following reasons:
> - No cover email and unclear target (see
> https://canonical-kernel-docs.readthedocs-hosted.com/en/latest/reference/stable-patch-format/#subject-line)
> - non-upstream patch with unclear history
>
> Given the heavily increased burden of maintaining security we have to
> stick to upstream as close as possible.
>
> -Stefan>   drivers/phy/qualcomm/phy-qcom-edp.c | 175
> ++++++++++++++++++++--------
> >   1 file changed, 125 insertions(+), 50 deletions(-)
> >
> > diff --git a/drivers/phy/qualcomm/phy-qcom-edp.c b/drivers/phy/qualcomm/phy-qcom-edp.c
> > index a391c29463ef6..ecd7b535c903f 100644
> > --- a/drivers/phy/qualcomm/phy-qcom-edp.c
> > +++ b/drivers/phy/qualcomm/phy-qcom-edp.c
> > @@ -48,13 +48,10 @@
> >   /* LANE_TXn registers */
> >   #define TXn_CLKBUF_ENABLE                       0x0000
> >   #define TXn_TX_EMP_POST1_LVL                    0x0004
> > -
> >   #define TXn_TX_DRV_LVL                          0x0014
> >   #define TXn_TX_DRV_LVL_OFFSET                   0x0018
> >   #define TXn_RESET_TSYNC_EN                      0x001c
> > -#define TXn_LDO_CONFIG                          0x0084
> >   #define TXn_TX_BAND                             0x0028
> > -
> >   #define TXn_RES_CODE_LANE_OFFSET_TX0            0x0044
> >   #define TXn_RES_CODE_LANE_OFFSET_TX1            0x0048
> >
> > @@ -64,6 +61,7 @@
> >   #define TXn_LANE_MODE_1                         0x0064
> >
> >   #define TXn_TRAN_DRVR_EMP_EN                    0x0078
> > +#define TXn_LDO_CONFIG                          0x0084
> >
> >   struct qcom_edp_swing_pre_emph_cfg {
> >       const u8 (*swing_hbr_rbr)[4][4];
> > @@ -82,6 +80,12 @@ struct phy_ver_ops {
> >       int (*com_configure_pll)(const struct qcom_edp *edp);
> >       int (*com_configure_ssc)(const struct qcom_edp *edp);
> >       int (*com_ldo_config)(const struct qcom_edp *edp);
> > +     int (*prepare_power_on)(const struct qcom_edp *edp);
> > +     int (*configure_tx_pre_pll)(const struct qcom_edp *edp);
> > +     int (*configure_rate_pcs)(const struct qcom_edp *edp,
> > +                               unsigned long *pixel_freq);
> > +     void (*configure_lanes_after_pll)(const struct qcom_edp *edp);
> > +     int (*finish_power_on)(const struct qcom_edp *edp);
> >   };
> >
> >   struct qcom_edp_phy_cfg {
> > @@ -117,6 +121,13 @@ struct qcom_edp {
> >       bool is_edp;
> >   };
> >
> > +static int qcom_edp_prepare_power_on_v46(const struct qcom_edp *edp);
> > +static int qcom_edp_configure_tx_pre_pll_v46(const struct qcom_edp *edp);
> > +static int qcom_edp_configure_rate_pcs_v46(const struct qcom_edp *edp,
> > +                                        unsigned long *pixel_freq);
> > +static void qcom_edp_configure_lanes_after_pll_v46(const struct qcom_edp *edp);
> > +static int qcom_edp_finish_power_on_v46(const struct qcom_edp *edp);
> > +
> >   static const u8 dp_swing_hbr_rbr[4][4] = {
> >       { 0x07, 0x0f, 0x16, 0x1f },
> >       { 0x11, 0x1e, 0x1f, 0xff },
> > @@ -653,6 +664,11 @@ static const struct phy_ver_ops qcom_edp_phy_ops_v3 = {
> >       .com_configure_pll      = qcom_edp_com_configure_pll_v4,
> >       .com_configure_ssc      = qcom_edp_com_configure_ssc_v4,
> >       .com_ldo_config         = qcom_edp_ldo_config_v3,
> > +     .prepare_power_on       = qcom_edp_prepare_power_on_v46,
> > +     .configure_tx_pre_pll   = qcom_edp_configure_tx_pre_pll_v46,
> > +     .configure_rate_pcs     = qcom_edp_configure_rate_pcs_v46,
> > +     .configure_lanes_after_pll = qcom_edp_configure_lanes_after_pll_v46,
> > +     .finish_power_on        = qcom_edp_finish_power_on_v46,
> >   };
> >
> >   static const struct phy_ver_ops qcom_edp_phy_ops_v4 = {
> > @@ -663,6 +679,11 @@ static const struct phy_ver_ops qcom_edp_phy_ops_v4 = {
> >       .com_configure_pll      = qcom_edp_com_configure_pll_v4,
> >       .com_configure_ssc      = qcom_edp_com_configure_ssc_v4,
> >       .com_ldo_config         = qcom_edp_ldo_config_v4,
> > +     .prepare_power_on       = qcom_edp_prepare_power_on_v46,
> > +     .configure_tx_pre_pll   = qcom_edp_configure_tx_pre_pll_v46,
> > +     .configure_rate_pcs     = qcom_edp_configure_rate_pcs_v46,
> > +     .configure_lanes_after_pll = qcom_edp_configure_lanes_after_pll_v46,
> > +     .finish_power_on        = qcom_edp_finish_power_on_v46,
> >   };
> >
> >   static const struct qcom_edp_phy_cfg sa8775p_dp_phy_cfg = {
> > @@ -898,6 +919,11 @@ static const struct phy_ver_ops qcom_edp_phy_ops_v6 = {
> >       .com_configure_pll      = qcom_edp_com_configure_pll_v6,
> >       .com_configure_ssc      = qcom_edp_com_configure_ssc_v6,
> >       .com_ldo_config         = qcom_edp_ldo_config_v6,
> > +     .prepare_power_on       = qcom_edp_prepare_power_on_v46,
> > +     .configure_tx_pre_pll   = qcom_edp_configure_tx_pre_pll_v46,
> > +     .configure_rate_pcs     = qcom_edp_configure_rate_pcs_v46,
> > +     .configure_lanes_after_pll = qcom_edp_configure_lanes_after_pll_v46,
> > +     .finish_power_on        = qcom_edp_finish_power_on_v46,
> >   };
> >
> >   static struct qcom_edp_phy_cfg x1e80100_phy_cfg = {
> > @@ -1079,6 +1105,11 @@ static const struct phy_ver_ops qcom_edp_phy_ops_v8 = {
> >       .com_configure_pll      = qcom_edp_com_configure_pll_v8,
> >       .com_configure_ssc      = qcom_edp_com_configure_ssc_v8,
> >       .com_ldo_config         = qcom_edp_ldo_config_v6,
> > +     .prepare_power_on       = qcom_edp_prepare_power_on_v46,
> > +     .configure_tx_pre_pll   = qcom_edp_configure_tx_pre_pll_v46,
> > +     .configure_rate_pcs     = qcom_edp_configure_rate_pcs_v46,
> > +     .configure_lanes_after_pll = qcom_edp_configure_lanes_after_pll_v46,
> > +     .finish_power_on        = qcom_edp_finish_power_on_v46,
> >   };
> >
> >   static struct qcom_edp_phy_cfg glymur_phy_cfg = {
> > @@ -1089,81 +1120,49 @@ static struct qcom_edp_phy_cfg glymur_phy_cfg = {
> >       .ver_ops = &qcom_edp_phy_ops_v8,
> >   };
> >
> > -static int qcom_edp_phy_power_on(struct phy *phy)
> > +static int qcom_edp_prepare_power_on_v46(const struct qcom_edp *edp)
> >   {
> > -     const struct qcom_edp *edp = phy_get_drvdata(phy);
> > -     u32 bias0_en, drvr0_en, bias1_en, drvr1_en;
> > -     unsigned long pixel_freq;
> > -     int ret;
> > -     u32 val;
> > -     u8 cfg1;
> > -
> > -     ret = edp->cfg->ver_ops->com_power_on(edp);
> > -     if (ret)
> > -             return ret;
> > -
> > -     ret = edp->cfg->ver_ops->com_ldo_config(edp);
> > -     if (ret)
> > -             return ret;
> > -
> > -     writel(0x00, edp->tx0 + TXn_LANE_MODE_1);
> > -     writel(0x00, edp->tx1 + TXn_LANE_MODE_1);
> > -
> > -     if (edp->dp_opts.ssc) {
> > -             ret = qcom_edp_configure_ssc(edp);
> > -             if (ret)
> > -                     return ret;
> > -     }
> > -
> > -     ret = qcom_edp_configure_pll(edp);
> > -     if (ret)
> > -             return ret;
> > +     return 0;
> > +}
> >
> > -     /* TX Lane configuration */
> > +static int qcom_edp_configure_tx_pre_pll_v46(const struct qcom_edp *edp)
> > +{
> >       writel(0x05, edp->edp + DP_PHY_TX0_TX1_LANE_CTL);
> >       writel(0x05, edp->edp + DP_PHY_TX2_TX3_LANE_CTL);
> >
> > -     /* TX-0 register configuration */
> >       writel(0x03, edp->tx0 + TXn_TRANSCEIVER_BIAS_EN);
> >       writel(0x0f, edp->tx0 + TXn_CLKBUF_ENABLE);
> >       writel(0x03, edp->tx0 + TXn_RESET_TSYNC_EN);
> >       writel(0x01, edp->tx0 + TXn_TRAN_DRVR_EMP_EN);
> >       writel(0x04, edp->tx0 + TXn_TX_BAND);
> >
> > -     /* TX-1 register configuration */
> >       writel(0x03, edp->tx1 + TXn_TRANSCEIVER_BIAS_EN);
> >       writel(0x0f, edp->tx1 + TXn_CLKBUF_ENABLE);
> >       writel(0x03, edp->tx1 + TXn_RESET_TSYNC_EN);
> >       writel(0x01, edp->tx1 + TXn_TRAN_DRVR_EMP_EN);
> >       writel(0x04, edp->tx1 + TXn_TX_BAND);
> >
> > -     ret = qcom_edp_set_vco_div(edp, &pixel_freq);
> > -     if (ret)
> > -             return ret;
> > -
> > -     writel(0x01, edp->edp + DP_PHY_CFG);
> > -     writel(0x05, edp->edp + DP_PHY_CFG);
> > -     writel(0x01, edp->edp + DP_PHY_CFG);
> > -     writel(0x09, edp->edp + DP_PHY_CFG);
> > +     return 0;
> > +}
> >
> > -     ret = edp->cfg->ver_ops->com_resetsm_cntrl(edp);
> > -     if (ret)
> > -             return ret;
> > +static void qcom_edp_configure_lanes_after_pll_v46(const struct qcom_edp *edp)
> > +{
> > +     u32 bias0_en, drvr0_en, bias1_en, drvr1_en;
> > +     u8 cfg1;
> >
> > -     writel(0x19, edp->edp + DP_PHY_CFG);
> >       writel(0x1f, edp->tx0 + TXn_HIGHZ_DRVR_EN);
> >       writel(0x04, edp->tx0 + TXn_HIGHZ_DRVR_EN);
> >       writel(0x00, edp->tx0 + TXn_TX_POL_INV);
> >       writel(0x1f, edp->tx1 + TXn_HIGHZ_DRVR_EN);
> >       writel(0x04, edp->tx1 + TXn_HIGHZ_DRVR_EN);
> >       writel(0x00, edp->tx1 + TXn_TX_POL_INV);
> > +
> >       writel(0x10, edp->tx0 + TXn_TX_DRV_LVL_OFFSET);
> >       writel(0x10, edp->tx1 + TXn_TX_DRV_LVL_OFFSET);
> >       writel(0x11, edp->tx0 + TXn_RES_CODE_LANE_OFFSET_TX0);
> >       writel(0x11, edp->tx0 + TXn_RES_CODE_LANE_OFFSET_TX1);
> >       writel(0x11, edp->tx1 + TXn_RES_CODE_LANE_OFFSET_TX0);
> >       writel(0x11, edp->tx1 + TXn_RES_CODE_LANE_OFFSET_TX1);
> > -
> >       writel(0x10, edp->tx0 + TXn_TX_EMP_POST1_LVL);
> >       writel(0x10, edp->tx1 + TXn_TX_EMP_POST1_LVL);
> >       writel(0x1f, edp->tx0 + TXn_TX_DRV_LVL);
> > @@ -1194,14 +1193,90 @@ static int qcom_edp_phy_power_on(struct phy *phy)
> >       writel(drvr1_en, edp->tx1 + TXn_HIGHZ_DRVR_EN);
> >       writel(bias1_en, edp->tx1 + TXn_TRANSCEIVER_BIAS_EN);
> >       writel(cfg1, edp->edp + DP_PHY_CFG_1);
> > +}
> > +
> > +static int qcom_edp_configure_rate_pcs_v46(const struct qcom_edp *edp,
> > +                                        unsigned long *pixel_freq)
> > +{
> > +     return qcom_edp_set_vco_div(edp, pixel_freq);
> > +}
> > +
> > +static int qcom_edp_start_pll(const struct qcom_edp *edp)
> > +{
> > +     int ret;
> > +
> > +     writel(0x01, edp->edp + DP_PHY_CFG);
> > +     writel(0x05, edp->edp + DP_PHY_CFG);
> > +     writel(0x01, edp->edp + DP_PHY_CFG);
> > +     writel(0x09, edp->edp + DP_PHY_CFG);
> > +
> > +     ret = edp->cfg->ver_ops->com_resetsm_cntrl(edp);
> > +     if (ret)
> > +             return ret;
> > +
> > +     writel(0x19, edp->edp + DP_PHY_CFG);
> > +
> > +     return 0;
> > +}
> > +
> > +static int qcom_edp_finish_power_on_v46(const struct qcom_edp *edp)
> > +{
> > +     u32 val;
> >
> >       writel(0x18, edp->edp + DP_PHY_CFG);
> >       usleep_range(100, 1000);
> > -
> >       writel(0x19, edp->edp + DP_PHY_CFG);
> >
> > -     ret = readl_poll_timeout(edp->edp + DP_PHY_STATUS,
> > -                              val, val & BIT(1), 500, 10000);
> > +     return readl_poll_timeout(edp->edp + DP_PHY_STATUS, val, val & BIT(1),
> > +                               500, 10000);
> > +}
> > +
> > +static int qcom_edp_phy_power_on(struct phy *phy)
> > +{
> > +     const struct qcom_edp *edp = phy_get_drvdata(phy);
> > +     unsigned long pixel_freq;
> > +     int ret;
> > +
> > +     ret = edp->cfg->ver_ops->com_power_on(edp);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = edp->cfg->ver_ops->prepare_power_on(edp);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = edp->cfg->ver_ops->com_ldo_config(edp);
> > +     if (ret)
> > +             return ret;
> > +
> > +     writel(0x00, edp->tx0 + TXn_LANE_MODE_1);
> > +     writel(0x00, edp->tx1 + TXn_LANE_MODE_1);
> > +
> > +     if (edp->dp_opts.ssc) {
> > +             ret = qcom_edp_configure_ssc(edp);
> > +             if (ret)
> > +                     return ret;
> > +     }
> > +
> > +     ret = qcom_edp_configure_pll(edp);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = edp->cfg->ver_ops->configure_tx_pre_pll(edp);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = edp->cfg->ver_ops->configure_rate_pcs(edp, &pixel_freq);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = qcom_edp_start_pll(edp);
> > +     if (ret)
> > +             return ret;
> > +
> > +     edp->cfg->ver_ops->configure_lanes_after_pll(edp);
> > +
> > +     ret = edp->cfg->ver_ops->finish_power_on(edp);
> >       if (ret)
> >               return ret;
> >
>



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