Re: [Intel-gfx] [PATCH 09/16] drm/i915: Query the vswing levels per-lane for icl mg phy

Ville Syrjälä
2021-11-01T09:57:00Z

On Fri, Oct 29, 2021 at 09:59:11PM +0000, Souza, Jose wrote:
> On Wed, 2021-10-06 at 23:49 +0300, Ville Syrjala wrote:
> > From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> >
> > Prepare for per-lane drive settings by querying the desired vswing
> > level per-lane.
> >
> > Note that the code only does two loops, with each one writing the
> > levels for two TX lanes.
> >
> > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > ---
> > drivers/gpu/drm/i915/display/intel_ddi.c | 13 ++++++++++++-
> > 1 file changed, 12 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> > index 4c400f0e7347..1874a2ca8f3b 100644
> > --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> > +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> > @@ -1163,7 +1163,6 @@ static void icl_mg_phy_set_signal_levels(struct intel_encoder *encoder,
> > {
> > struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
> > enum tc_port tc_port = intel_port_to_tc(dev_priv, encoder->port);
> > - int level = intel_ddi_level(encoder, crtc_state, 0);
> > const struct intel_ddi_buf_trans *trans;
> > int n_entries, ln;
> > u32 val;
> > @@ -1188,12 +1187,18 @@ static void icl_mg_phy_set_signal_levels(struct intel_encoder *encoder,
> >
> > /* Program MG_TX_SWINGCTRL with values from vswing table */
> > for (ln = 0; ln < 2; ln++) {
> > + int level;
> > +
> > + level = intel_ddi_level(encoder, crtc_state, 2*ln+0);
> > +
> > val = intel_de_read(dev_priv, MG_TX1_SWINGCTRL(ln, tc_port));
> > val &= ~CRI_TXDEEMPH_OVERRIDE_17_12_MASK;
> > val |= CRI_TXDEEMPH_OVERRIDE_17_12(
> > trans->entries[level].mg.cri_txdeemph_override_17_12);
> > intel_de_write(dev_priv, MG_TX1_SWINGCTRL(ln, tc_port), val);
> >
> > + level = intel_ddi_level(encoder, crtc_state, 2*ln+1);
> > +
> > val = intel_de_read(dev_priv, MG_TX2_SWINGCTRL(ln, tc_port));
> > val &= ~CRI_TXDEEMPH_OVERRIDE_17_12_MASK;
> > val |= CRI_TXDEEMPH_OVERRIDE_17_12(
> > @@ -1203,6 +1208,10 @@ static void icl_mg_phy_set_signal_levels(struct intel_encoder *encoder,
> >
> > /* Program MG_TX_DRVCTRL with values from vswing table */
> > for (ln = 0; ln < 2; ln++) {
> > + int level;
> > +
> > + level = intel_ddi_level(encoder, crtc_state, 2*ln+0);
> > +
> > val = intel_de_read(dev_priv, MG_TX1_DRVCTRL(ln, tc_port));
> > val &= ~(CRI_TXDEEMPH_OVERRIDE_11_6_MASK |
> > CRI_TXDEEMPH_OVERRIDE_5_0_MASK);
> > @@ -1213,6 +1222,8 @@ static void icl_mg_phy_set_signal_levels(struct intel_encoder *encoder,
> > CRI_TXDEEMPH_OVERRIDE_EN;
> > intel_de_write(dev_priv, MG_TX1_DRVCTRL(ln, tc_port), val);
> >
> > + level = intel_ddi_level(encoder, crtc_state, 2*ln+1);
>
> I believe our code style requires that we have spaces, so it should be (2 * ln + 1).

Neither is really good, but the one with spaces just looks ugly IMO.

>
> With the answers requested in the previous patch:
>
> Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
>
>
> > +
> > val = intel_de_read(dev_priv, MG_TX2_DRVCTRL(ln, tc_port));
> > val &= ~(CRI_TXDEEMPH_OVERRIDE_11_6_MASK |
> > CRI_TXDEEMPH_OVERRIDE_5_0_MASK);
>

--
Ville Syrjälä
Intel