| Message ID | 20220919145659.293492-1-gustavo.sousa@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/i915: Move hotplug inversion logic into separate helper | expand |
On Mon, Sep 19, 2022 at 11:56:59AM -0300, Gustavo Sousa wrote: >Make the code more readable, which will be more apparent as new >platforms with different hotplug inversion needs are added. > >Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com> >--- > drivers/gpu/drm/i915/i915_irq.c | 25 ++++++++++++++++--------- > 1 file changed, 16 insertions(+), 9 deletions(-) > >diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c >index de06f293e173..c53d21ae197f 100644 >--- a/drivers/gpu/drm/i915/i915_irq.c >+++ b/drivers/gpu/drm/i915/i915_irq.c >@@ -3263,6 +3263,21 @@ static void cherryview_irq_reset(struct drm_i915_private *dev_priv) > spin_unlock_irq(&dev_priv->irq_lock); > } > >+static void setup_hotplug_inversion(struct drm_i915_private *dev_priv) new users of drm_i915_private should use "i915" as variable name rather than dev_priv. other than that, Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com> Lucas De Marchi >+{ >+ u32 invert_bits; >+ >+ if (HAS_PCH_DG1(dev_priv)) >+ invert_bits = INVERT_DDIA_HPD | >+ INVERT_DDIB_HPD | >+ INVERT_DDIC_HPD | >+ INVERT_DDID_HPD; >+ else >+ return; >+ >+ intel_uncore_rmw(&dev_priv->uncore, SOUTH_CHICKEN1, 0, invert_bits); >+} >+ > static u32 ibx_hotplug_enables(struct drm_i915_private *i915, > enum hpd_pin pin) > { >@@ -3413,15 +3428,7 @@ static u32 gen11_hotplug_enables(struct drm_i915_private *i915, > > static void dg1_hpd_irq_setup(struct drm_i915_private *dev_priv) > { >- u32 val; >- >- val = intel_uncore_read(&dev_priv->uncore, SOUTH_CHICKEN1); >- val |= (INVERT_DDIA_HPD | >- INVERT_DDIB_HPD | >- INVERT_DDIC_HPD | >- INVERT_DDID_HPD); >- intel_uncore_write(&dev_priv->uncore, SOUTH_CHICKEN1, val); >- >+ setup_hotplug_inversion(dev_priv); > icp_hpd_irq_setup(dev_priv); > } > >-- >2.37.3 >
On Mon, 19 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: > Make the code more readable, which will be more apparent as new > platforms with different hotplug inversion needs are added. > > Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com> > --- > drivers/gpu/drm/i915/i915_irq.c | 25 ++++++++++++++++--------- > 1 file changed, 16 insertions(+), 9 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c > index de06f293e173..c53d21ae197f 100644 > --- a/drivers/gpu/drm/i915/i915_irq.c > +++ b/drivers/gpu/drm/i915/i915_irq.c > @@ -3263,6 +3263,21 @@ static void cherryview_irq_reset(struct drm_i915_private *dev_priv) > spin_unlock_irq(&dev_priv->irq_lock); > } > > +static void setup_hotplug_inversion(struct drm_i915_private *dev_priv) > +{ > + u32 invert_bits; > + > + if (HAS_PCH_DG1(dev_priv)) > + invert_bits = INVERT_DDIA_HPD | > + INVERT_DDIB_HPD | > + INVERT_DDIC_HPD | > + INVERT_DDID_HPD; Nitpick, the indentation will be off compared to automated indentation. > + else > + return; > + > + intel_uncore_rmw(&dev_priv->uncore, SOUTH_CHICKEN1, 0, invert_bits); > +} > + > static u32 ibx_hotplug_enables(struct drm_i915_private *i915, > enum hpd_pin pin) > { > @@ -3413,15 +3428,7 @@ static u32 gen11_hotplug_enables(struct drm_i915_private *i915, > > static void dg1_hpd_irq_setup(struct drm_i915_private *dev_priv) > { > - u32 val; > - > - val = intel_uncore_read(&dev_priv->uncore, SOUTH_CHICKEN1); > - val |= (INVERT_DDIA_HPD | > - INVERT_DDIB_HPD | > - INVERT_DDIC_HPD | > - INVERT_DDID_HPD); > - intel_uncore_write(&dev_priv->uncore, SOUTH_CHICKEN1, val); > - > + setup_hotplug_inversion(dev_priv); Since you're already in a platform specific function here, seems a bit odd to call a new generic function that needs to have another if ladder platform check. What are we gaining here? The end result is de-duplicating just one line of intel_uncore_rmw(). I'm not convinced. BR, Jani. > icp_hpd_irq_setup(dev_priv); > }
On Tue, Sep 20, 2022 at 12:01:36AM -0700, Lucas De Marchi wrote: > On Mon, Sep 19, 2022 at 11:56:59AM -0300, Gustavo Sousa wrote: > > Make the code more readable, which will be more apparent as new > > platforms with different hotplug inversion needs are added. > > > > Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com> > > --- > > drivers/gpu/drm/i915/i915_irq.c | 25 ++++++++++++++++--------- > > 1 file changed, 16 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c > > index de06f293e173..c53d21ae197f 100644 > > --- a/drivers/gpu/drm/i915/i915_irq.c > > +++ b/drivers/gpu/drm/i915/i915_irq.c > > @@ -3263,6 +3263,21 @@ static void cherryview_irq_reset(struct drm_i915_private *dev_priv) > > spin_unlock_irq(&dev_priv->irq_lock); > > } > > > > +static void setup_hotplug_inversion(struct drm_i915_private *dev_priv) > > new users of drm_i915_private should use "i915" as variable name rather > than dev_priv. Thanks. I will update this. Is there any documentation where we can find information like this? > > other than that, Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com> > > > Lucas De Marchi > > > +{ > > + u32 invert_bits; > > + > > + if (HAS_PCH_DG1(dev_priv)) > > + invert_bits = INVERT_DDIA_HPD | > > + INVERT_DDIB_HPD | > > + INVERT_DDIC_HPD | > > + INVERT_DDID_HPD; > > + else > > + return; > > + > > + intel_uncore_rmw(&dev_priv->uncore, SOUTH_CHICKEN1, 0, invert_bits); > > +} > > + > > static u32 ibx_hotplug_enables(struct drm_i915_private *i915, > > enum hpd_pin pin) > > { > > @@ -3413,15 +3428,7 @@ static u32 gen11_hotplug_enables(struct drm_i915_private *i915, > > > > static void dg1_hpd_irq_setup(struct drm_i915_private *dev_priv) > > { > > - u32 val; > > - > > - val = intel_uncore_read(&dev_priv->uncore, SOUTH_CHICKEN1); > > - val |= (INVERT_DDIA_HPD | > > - INVERT_DDIB_HPD | > > - INVERT_DDIC_HPD | > > - INVERT_DDID_HPD); > > - intel_uncore_write(&dev_priv->uncore, SOUTH_CHICKEN1, val); > > - > > + setup_hotplug_inversion(dev_priv); > > icp_hpd_irq_setup(dev_priv); > > } > > > > -- > > 2.37.3 > >
Hi, Jani. On Tue, Sep 20, 2022 at 10:19:53AM +0300, Jani Nikula wrote: > On Mon, 19 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: > > Make the code more readable, which will be more apparent as new > > platforms with different hotplug inversion needs are added. > > > > Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com> > > --- > > drivers/gpu/drm/i915/i915_irq.c | 25 ++++++++++++++++--------- > > 1 file changed, 16 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c > > index de06f293e173..c53d21ae197f 100644 > > --- a/drivers/gpu/drm/i915/i915_irq.c > > +++ b/drivers/gpu/drm/i915/i915_irq.c > > @@ -3263,6 +3263,21 @@ static void cherryview_irq_reset(struct drm_i915_private *dev_priv) > > spin_unlock_irq(&dev_priv->irq_lock); > > } > > > > +static void setup_hotplug_inversion(struct drm_i915_private *dev_priv) > > +{ > > + u32 invert_bits; > > + > > + if (HAS_PCH_DG1(dev_priv)) > > + invert_bits = INVERT_DDIA_HPD | > > + INVERT_DDIB_HPD | > > + INVERT_DDIC_HPD | > > + INVERT_DDID_HPD; > > Nitpick, the indentation will be off compared to automated indentation. What do you mean by automated indentation? > > > + else > > + return; > > + > > + intel_uncore_rmw(&dev_priv->uncore, SOUTH_CHICKEN1, 0, invert_bits); > > +} > > + > > static u32 ibx_hotplug_enables(struct drm_i915_private *i915, > > enum hpd_pin pin) > > { > > @@ -3413,15 +3428,7 @@ static u32 gen11_hotplug_enables(struct drm_i915_private *i915, > > > > static void dg1_hpd_irq_setup(struct drm_i915_private *dev_priv) > > { > > - u32 val; > > - > > - val = intel_uncore_read(&dev_priv->uncore, SOUTH_CHICKEN1); > > - val |= (INVERT_DDIA_HPD | > > - INVERT_DDIB_HPD | > > - INVERT_DDIC_HPD | > > - INVERT_DDID_HPD); > > - intel_uncore_write(&dev_priv->uncore, SOUTH_CHICKEN1, val); > > - > > + setup_hotplug_inversion(dev_priv); > > Since you're already in a platform specific function here, seems a bit > odd to call a new generic function that needs to have another if ladder > platform check. What are we gaining here? The end result is > de-duplicating just one line of intel_uncore_rmw(). I'm not convinced. It is true that the proposed refactor repeats a platform check, but the proposed refactor has its benefits. As more platforms with hotplug inversion needs are added (e.g. MTL), we will have a common place for the logic of hotplug inversion. That arguably makes the code more readable and makes future refactors easier when we need split a function that has become too complex due to platform checks. To make that last point clearer, I am quoting Lucas' (copied here as well) comment (which was what convinced me) from a discussion regarding the advantage of using such a helper: that is what helpers are for, so you don't have to open code it in every platform-fork of the function that needs it. See how the various "Sequences to initialize display" are done in the driver... When we are extending it to a future platform, if the change is small enough we just add e few if/else in the same function. But it doesn't take too long for those functions to become unreadable if there are several branches the code path may take. So then we "fork" the function for a new platform, but reuse the helpers doing the individual steps. -- Gustavo Sousa
On Tue, Sep 20, 2022 at 02:04:33PM -0300, Gustavo Sousa wrote: >Hi, Jani. > >On Tue, Sep 20, 2022 at 10:19:53AM +0300, Jani Nikula wrote: >> On Mon, 19 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: >> > Make the code more readable, which will be more apparent as new >> > platforms with different hotplug inversion needs are added. >> > >> > Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com> >> > --- >> > drivers/gpu/drm/i915/i915_irq.c | 25 ++++++++++++++++--------- >> > 1 file changed, 16 insertions(+), 9 deletions(-) >> > >> > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c >> > index de06f293e173..c53d21ae197f 100644 >> > --- a/drivers/gpu/drm/i915/i915_irq.c >> > +++ b/drivers/gpu/drm/i915/i915_irq.c >> > @@ -3263,6 +3263,21 @@ static void cherryview_irq_reset(struct drm_i915_private *dev_priv) >> > spin_unlock_irq(&dev_priv->irq_lock); >> > } >> > >> > +static void setup_hotplug_inversion(struct drm_i915_private *dev_priv) >> > +{ >> > + u32 invert_bits; >> > + >> > + if (HAS_PCH_DG1(dev_priv)) >> > + invert_bits = INVERT_DDIA_HPD | >> > + INVERT_DDIB_HPD | >> > + INVERT_DDIC_HPD | >> > + INVERT_DDID_HPD; >> >> Nitpick, the indentation will be off compared to automated indentation. > >What do you mean by automated indentation? > >> >> > + else >> > + return; >> > + >> > + intel_uncore_rmw(&dev_priv->uncore, SOUTH_CHICKEN1, 0, invert_bits); >> > +} >> > + >> > static u32 ibx_hotplug_enables(struct drm_i915_private *i915, >> > enum hpd_pin pin) >> > { >> > @@ -3413,15 +3428,7 @@ static u32 gen11_hotplug_enables(struct drm_i915_private *i915, >> > >> > static void dg1_hpd_irq_setup(struct drm_i915_private *dev_priv) >> > { >> > - u32 val; >> > - >> > - val = intel_uncore_read(&dev_priv->uncore, SOUTH_CHICKEN1); >> > - val |= (INVERT_DDIA_HPD | >> > - INVERT_DDIB_HPD | >> > - INVERT_DDIC_HPD | >> > - INVERT_DDID_HPD); >> > - intel_uncore_write(&dev_priv->uncore, SOUTH_CHICKEN1, val); >> > - >> > + setup_hotplug_inversion(dev_priv); >> >> Since you're already in a platform specific function here, seems a bit >> odd to call a new generic function that needs to have another if ladder >> platform check. What are we gaining here? The end result is >> de-duplicating just one line of intel_uncore_rmw(). I'm not convinced. > >It is true that the proposed refactor repeats a platform check, but the proposed >refactor has its benefits. As more platforms with hotplug inversion needs are >added (e.g. MTL), we will have a common place for the logic of hotplug >inversion. That arguably makes the code more readable and makes future refactors >easier when we need split a function that has become too complex due to platform >checks. > >To make that last point clearer, I am quoting Lucas' (copied here as well) >comment (which was what convinced me) from a discussion regarding the advantage >of using such a helper: > > that is what helpers are for, so you don't have to open code it in every > platform-fork of the function that needs it. See how the various > "Sequences to initialize display" are done in the driver... When we are > extending it to a future platform, if the change is small enough we just > add e few if/else in the same function. But it doesn't take too long for > those functions to become unreadable if there are several branches the > code path may take. So then we "fork" the function for a new platform, > but reuse the helpers doing the individual steps. the missing information here is that there are changes in the pipeline for platforms that have different bits to be inverted, or none at all, with a different register to program. Adding the if/else in this function seems unrelated churn. Another possibility would be to just let the caller handle the if/else decision, passing the bits (and possibly register) to invert. The noise in xxx_hpd_irq_setup() function may be avoid by #define INVERT_DII_HPD (INVERT_DDIA_HPD | INVERT_DDIB_HPD | INVERT_DDIC_HPD | INVERT_DDID_HPD) #define XXX_INVERT_DII_HPD (...) Third possibility since the function is already very small is to just go ahead and use another _setup() for the next platforms. Lucas De Marchi
On Tue, 20 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: > Hi, Jani. > > On Tue, Sep 20, 2022 at 10:19:53AM +0300, Jani Nikula wrote: >> On Mon, 19 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: >> > Make the code more readable, which will be more apparent as new >> > platforms with different hotplug inversion needs are added. >> > >> > Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com> >> > --- >> > drivers/gpu/drm/i915/i915_irq.c | 25 ++++++++++++++++--------- >> > 1 file changed, 16 insertions(+), 9 deletions(-) >> > >> > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c >> > index de06f293e173..c53d21ae197f 100644 >> > --- a/drivers/gpu/drm/i915/i915_irq.c >> > +++ b/drivers/gpu/drm/i915/i915_irq.c >> > @@ -3263,6 +3263,21 @@ static void cherryview_irq_reset(struct drm_i915_private *dev_priv) >> > spin_unlock_irq(&dev_priv->irq_lock); >> > } >> > >> > +static void setup_hotplug_inversion(struct drm_i915_private *dev_priv) >> > +{ >> > + u32 invert_bits; >> > + >> > + if (HAS_PCH_DG1(dev_priv)) >> > + invert_bits = INVERT_DDIA_HPD | >> > + INVERT_DDIB_HPD | >> > + INVERT_DDIC_HPD | >> > + INVERT_DDID_HPD; >> >> Nitpick, the indentation will be off compared to automated indentation. > > What do you mean by automated indentation? For example, hit TAB on the lines using a smart enough editor, which has been configured to follow kernel coding style. ;) BR, Jani.
On Tue, 20 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: > On Tue, Sep 20, 2022 at 12:01:36AM -0700, Lucas De Marchi wrote: >> On Mon, Sep 19, 2022 at 11:56:59AM -0300, Gustavo Sousa wrote: >> > Make the code more readable, which will be more apparent as new >> > platforms with different hotplug inversion needs are added. >> > >> > Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com> >> > --- >> > drivers/gpu/drm/i915/i915_irq.c | 25 ++++++++++++++++--------- >> > 1 file changed, 16 insertions(+), 9 deletions(-) >> > >> > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c >> > index de06f293e173..c53d21ae197f 100644 >> > --- a/drivers/gpu/drm/i915/i915_irq.c >> > +++ b/drivers/gpu/drm/i915/i915_irq.c >> > @@ -3263,6 +3263,21 @@ static void cherryview_irq_reset(struct drm_i915_private *dev_priv) >> > spin_unlock_irq(&dev_priv->irq_lock); >> > } >> > >> > +static void setup_hotplug_inversion(struct drm_i915_private *dev_priv) >> >> new users of drm_i915_private should use "i915" as variable name rather >> than dev_priv. > > Thanks. I will update this. > > Is there any documentation where we can find information like this? WIP: https://gitlab.freedesktop.org/jani/i915-check/-/blob/main/i915-style-guide.rst BR, Jani. > >> >> other than that, Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com> >> >> >> Lucas De Marchi >> >> > +{ >> > + u32 invert_bits; >> > + >> > + if (HAS_PCH_DG1(dev_priv)) >> > + invert_bits = INVERT_DDIA_HPD | >> > + INVERT_DDIB_HPD | >> > + INVERT_DDIC_HPD | >> > + INVERT_DDID_HPD; >> > + else >> > + return; >> > + >> > + intel_uncore_rmw(&dev_priv->uncore, SOUTH_CHICKEN1, 0, invert_bits); >> > +} >> > + >> > static u32 ibx_hotplug_enables(struct drm_i915_private *i915, >> > enum hpd_pin pin) >> > { >> > @@ -3413,15 +3428,7 @@ static u32 gen11_hotplug_enables(struct drm_i915_private *i915, >> > >> > static void dg1_hpd_irq_setup(struct drm_i915_private *dev_priv) >> > { >> > - u32 val; >> > - >> > - val = intel_uncore_read(&dev_priv->uncore, SOUTH_CHICKEN1); >> > - val |= (INVERT_DDIA_HPD | >> > - INVERT_DDIB_HPD | >> > - INVERT_DDIC_HPD | >> > - INVERT_DDID_HPD); >> > - intel_uncore_write(&dev_priv->uncore, SOUTH_CHICKEN1, val); >> > - >> > + setup_hotplug_inversion(dev_priv); >> > icp_hpd_irq_setup(dev_priv); >> > } >> > >> > -- >> > 2.37.3 >> >
On Tue, 20 Sep 2022, Lucas De Marchi <lucas.demarchi@intel.com> wrote: > On Tue, Sep 20, 2022 at 02:04:33PM -0300, Gustavo Sousa wrote: >>Hi, Jani. >> >>On Tue, Sep 20, 2022 at 10:19:53AM +0300, Jani Nikula wrote: >>> On Mon, 19 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: >>> > Make the code more readable, which will be more apparent as new >>> > platforms with different hotplug inversion needs are added. >>> > >>> > Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com> >>> > --- >>> > drivers/gpu/drm/i915/i915_irq.c | 25 ++++++++++++++++--------- >>> > 1 file changed, 16 insertions(+), 9 deletions(-) >>> > >>> > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c >>> > index de06f293e173..c53d21ae197f 100644 >>> > --- a/drivers/gpu/drm/i915/i915_irq.c >>> > +++ b/drivers/gpu/drm/i915/i915_irq.c >>> > @@ -3263,6 +3263,21 @@ static void cherryview_irq_reset(struct drm_i915_private *dev_priv) >>> > spin_unlock_irq(&dev_priv->irq_lock); >>> > } >>> > >>> > +static void setup_hotplug_inversion(struct drm_i915_private *dev_priv) >>> > +{ >>> > + u32 invert_bits; >>> > + >>> > + if (HAS_PCH_DG1(dev_priv)) >>> > + invert_bits = INVERT_DDIA_HPD | >>> > + INVERT_DDIB_HPD | >>> > + INVERT_DDIC_HPD | >>> > + INVERT_DDID_HPD; >>> >>> Nitpick, the indentation will be off compared to automated indentation. >> >>What do you mean by automated indentation? >> >>> >>> > + else >>> > + return; >>> > + >>> > + intel_uncore_rmw(&dev_priv->uncore, SOUTH_CHICKEN1, 0, invert_bits); >>> > +} >>> > + >>> > static u32 ibx_hotplug_enables(struct drm_i915_private *i915, >>> > enum hpd_pin pin) >>> > { >>> > @@ -3413,15 +3428,7 @@ static u32 gen11_hotplug_enables(struct drm_i915_private *i915, >>> > >>> > static void dg1_hpd_irq_setup(struct drm_i915_private *dev_priv) >>> > { >>> > - u32 val; >>> > - >>> > - val = intel_uncore_read(&dev_priv->uncore, SOUTH_CHICKEN1); >>> > - val |= (INVERT_DDIA_HPD | >>> > - INVERT_DDIB_HPD | >>> > - INVERT_DDIC_HPD | >>> > - INVERT_DDID_HPD); >>> > - intel_uncore_write(&dev_priv->uncore, SOUTH_CHICKEN1, val); >>> > - >>> > + setup_hotplug_inversion(dev_priv); >>> >>> Since you're already in a platform specific function here, seems a bit >>> odd to call a new generic function that needs to have another if ladder >>> platform check. What are we gaining here? The end result is >>> de-duplicating just one line of intel_uncore_rmw(). I'm not convinced. >> >>It is true that the proposed refactor repeats a platform check, but the proposed >>refactor has its benefits. As more platforms with hotplug inversion needs are >>added (e.g. MTL), we will have a common place for the logic of hotplug >>inversion. That arguably makes the code more readable and makes future refactors >>easier when we need split a function that has become too complex due to platform >>checks. >> >>To make that last point clearer, I am quoting Lucas' (copied here as well) >>comment (which was what convinced me) from a discussion regarding the advantage >>of using such a helper: >> >> that is what helpers are for, so you don't have to open code it in every >> platform-fork of the function that needs it. See how the various >> "Sequences to initialize display" are done in the driver... When we are >> extending it to a future platform, if the change is small enough we just >> add e few if/else in the same function. But it doesn't take too long for >> those functions to become unreadable if there are several branches the >> code path may take. So then we "fork" the function for a new platform, >> but reuse the helpers doing the individual steps. > > the missing information here is that there are changes in the pipeline > for platforms that have different bits to be inverted, or none at > all, with a different register to program. Adding the if/else in this > function seems unrelated churn. > > Another possibility would be to just let the caller handle the if/else > decision, passing the bits (and possibly register) to invert. The noise > in xxx_hpd_irq_setup() function may be avoid by > > #define INVERT_DII_HPD (INVERT_DDIA_HPD | INVERT_DDIB_HPD | INVERT_DDIC_HPD | INVERT_DDID_HPD) > #define XXX_INVERT_DII_HPD (...) > > Third possibility since the function is already very small is to just go > ahead and use another _setup() for the next platforms. IMO if you already have platform specific functions, it can get confusing if you call generic helpers that again spread out to platform specific functions, possibly with different conditions than the first one. We've had a bunch of those where you eventually realize there's conditions in the helper that never happen. I'd probably just add small *platform specific* hpd invert functions. dg1_hpd_invert() and mtl_hpd_invert() etc. Compare with *_hpd_detection_setup(), and wonder what that would look like if it were a generic helper. Pretty bad, huh? Also note how bxt actually handles hpd invert within bxt_hpd_detection_setup(). BR, Jani.
On Wed, Sep 21, 2022 at 11:21:00AM +0300, Jani Nikula wrote: > On Tue, 20 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: > > Hi, Jani. > > > > On Tue, Sep 20, 2022 at 10:19:53AM +0300, Jani Nikula wrote: > >> On Mon, 19 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: > >> > Make the code more readable, which will be more apparent as new > >> > platforms with different hotplug inversion needs are added. > >> > > >> > Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com> > >> > --- > >> > drivers/gpu/drm/i915/i915_irq.c | 25 ++++++++++++++++--------- > >> > 1 file changed, 16 insertions(+), 9 deletions(-) > >> > > >> > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c > >> > index de06f293e173..c53d21ae197f 100644 > >> > --- a/drivers/gpu/drm/i915/i915_irq.c > >> > +++ b/drivers/gpu/drm/i915/i915_irq.c > >> > @@ -3263,6 +3263,21 @@ static void cherryview_irq_reset(struct drm_i915_private *dev_priv) > >> > spin_unlock_irq(&dev_priv->irq_lock); > >> > } > >> > > >> > +static void setup_hotplug_inversion(struct drm_i915_private *dev_priv) > >> > +{ > >> > + u32 invert_bits; > >> > + > >> > + if (HAS_PCH_DG1(dev_priv)) > >> > + invert_bits = INVERT_DDIA_HPD | > >> > + INVERT_DDIB_HPD | > >> > + INVERT_DDIC_HPD | > >> > + INVERT_DDID_HPD; > >> > >> Nitpick, the indentation will be off compared to automated indentation. > > > > What do you mean by automated indentation? > > For example, hit TAB on the lines using a smart enough editor, which has > been configured to follow kernel coding style. ;) > I'm not sure I completely understand the issue. Could you provide an example of such a configuration? Is the problem here the spaces after the tabs to align each INVERT_DDI*? Would you suggest I just use tabs and do not align them to the first one? E.g.: invert_bits = INVERT_DDIA_HPD | INVERT_DDIB_HPD | INVERT_DDIC_HPD | INVERT_DDID_HPD; Another one: invert_bits = INVERT_DDIA_HPD | INVERT_DDIB_HPD | INVERT_DDIC_HPD | INVERT_DDID_HPD; Note: I'm using 8 spaces for instead tabs in the above examples for proper visual, but they would be tab characters in the source. -- Gustavo Sousa
On Wed, 21 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: > On Wed, Sep 21, 2022 at 11:21:00AM +0300, Jani Nikula wrote: >> On Tue, 20 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: >> > Hi, Jani. >> > >> > On Tue, Sep 20, 2022 at 10:19:53AM +0300, Jani Nikula wrote: >> >> On Mon, 19 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: >> >> > Make the code more readable, which will be more apparent as new >> >> > platforms with different hotplug inversion needs are added. >> >> > >> >> > Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com> >> >> > --- >> >> > drivers/gpu/drm/i915/i915_irq.c | 25 ++++++++++++++++--------- >> >> > 1 file changed, 16 insertions(+), 9 deletions(-) >> >> > >> >> > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c >> >> > index de06f293e173..c53d21ae197f 100644 >> >> > --- a/drivers/gpu/drm/i915/i915_irq.c >> >> > +++ b/drivers/gpu/drm/i915/i915_irq.c >> >> > @@ -3263,6 +3263,21 @@ static void cherryview_irq_reset(struct drm_i915_private *dev_priv) >> >> > spin_unlock_irq(&dev_priv->irq_lock); >> >> > } >> >> > >> >> > +static void setup_hotplug_inversion(struct drm_i915_private *dev_priv) >> >> > +{ >> >> > + u32 invert_bits; >> >> > + >> >> > + if (HAS_PCH_DG1(dev_priv)) >> >> > + invert_bits = INVERT_DDIA_HPD | >> >> > + INVERT_DDIB_HPD | >> >> > + INVERT_DDIC_HPD | >> >> > + INVERT_DDID_HPD; >> >> >> >> Nitpick, the indentation will be off compared to automated indentation. >> > >> > What do you mean by automated indentation? >> >> For example, hit TAB on the lines using a smart enough editor, which has >> been configured to follow kernel coding style. ;) >> > > I'm not sure I completely understand the issue. Could you provide an example of > such a configuration? I never indent anything manually. If I hit TAB in emacs (or run M-x indent-region), it'll indent the current line (or region) using the built-in "linux" style [1]. [1] https://www.gnu.org/software/emacs/manual/html_node/ccmode/Built_002din-Styles.html > Is the problem here the spaces after the tabs to align each INVERT_DDI*? Would > you suggest I just use tabs and do not align them to the first one? If a parenthesized element in round brackets is split to multiple lines, the indent is usually tabs first and then spaces to align everything after the open parenthesis. If there are no parenthesis, the indent is just tabs. Guess why the original dg1_hpd_irq_setup() has round brackets in the statement. ;) Though not everyone likes superfluous parenthesis for style. > E.g.: > > invert_bits = INVERT_DDIA_HPD | > INVERT_DDIB_HPD | > INVERT_DDIC_HPD | > INVERT_DDID_HPD; > > Another one: > > invert_bits = INVERT_DDIA_HPD | > INVERT_DDIB_HPD | > INVERT_DDIC_HPD | > INVERT_DDID_HPD; Your patch applied, re-indented, and tabs converted to spaces for visual here: if (HAS_PCH_DG1(dev_priv)) invert_bits = INVERT_DDIA_HPD | INVERT_DDIB_HPD | INVERT_DDIC_HPD | INVERT_DDID_HPD; Anyway, indentation isn't a very fruitful conversation in itself. The original nitpick was an off the cuff remark. I'm mostly trying to suggest to use tools that will do indentation and other things for you, so you don't have to worry about getting it right. BR, Jani. > > > Note: I'm using 8 spaces for instead tabs in the above examples for proper > visual, but they would be tab characters in the source. > > -- > Gustavo Sousa
On Thu, Sep 22, 2022 at 11:17:01AM +0300, Jani Nikula wrote: > On Wed, 21 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: > > On Wed, Sep 21, 2022 at 11:21:00AM +0300, Jani Nikula wrote: > >> On Tue, 20 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: > >> > Hi, Jani. > >> > > >> > On Tue, Sep 20, 2022 at 10:19:53AM +0300, Jani Nikula wrote: > >> >> On Mon, 19 Sep 2022, Gustavo Sousa <gustavo.sousa@intel.com> wrote: > >> >> > Make the code more readable, which will be more apparent as new > >> >> > platforms with different hotplug inversion needs are added. > >> >> > > >> >> > Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com> > >> >> > --- > >> >> > drivers/gpu/drm/i915/i915_irq.c | 25 ++++++++++++++++--------- > >> >> > 1 file changed, 16 insertions(+), 9 deletions(-) > >> >> > > >> >> > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c > >> >> > index de06f293e173..c53d21ae197f 100644 > >> >> > --- a/drivers/gpu/drm/i915/i915_irq.c > >> >> > +++ b/drivers/gpu/drm/i915/i915_irq.c > >> >> > @@ -3263,6 +3263,21 @@ static void cherryview_irq_reset(struct drm_i915_private *dev_priv) > >> >> > spin_unlock_irq(&dev_priv->irq_lock); > >> >> > } > >> >> > > >> >> > +static void setup_hotplug_inversion(struct drm_i915_private *dev_priv) > >> >> > +{ > >> >> > + u32 invert_bits; > >> >> > + > >> >> > + if (HAS_PCH_DG1(dev_priv)) > >> >> > + invert_bits = INVERT_DDIA_HPD | > >> >> > + INVERT_DDIB_HPD | > >> >> > + INVERT_DDIC_HPD | > >> >> > + INVERT_DDID_HPD; Just checked the source and it seems I'm the only oddball aligning stuff like this :-) > >> >> > >> >> Nitpick, the indentation will be off compared to automated indentation. > >> > > >> > What do you mean by automated indentation? > >> > >> For example, hit TAB on the lines using a smart enough editor, which has > >> been configured to follow kernel coding style. ;) > >> > > > > I'm not sure I completely understand the issue. Could you provide an example of > > such a configuration? > > I never indent anything manually. If I hit TAB in emacs (or run M-x > indent-region), it'll indent the current line (or region) using the > built-in "linux" style [1]. > > [1] https://www.gnu.org/software/emacs/manual/html_node/ccmode/Built_002din-Styles.html > > > Is the problem here the spaces after the tabs to align each INVERT_DDI*? Would > > you suggest I just use tabs and do not align them to the first one? > > If a parenthesized element in round brackets is split to multiple lines, > the indent is usually tabs first and then spaces to align everything > after the open parenthesis. If there are no parenthesis, the indent is > just tabs. > > Guess why the original dg1_hpd_irq_setup() has round brackets in the > statement. ;) Though not everyone likes superfluous parenthesis for > style. > > > E.g.: > > > > invert_bits = INVERT_DDIA_HPD | > > INVERT_DDIB_HPD | > > INVERT_DDIC_HPD | > > INVERT_DDID_HPD; > > > > Another one: > > > > invert_bits = INVERT_DDIA_HPD | > > INVERT_DDIB_HPD | > > INVERT_DDIC_HPD | > > INVERT_DDID_HPD; > > Your patch applied, re-indented, and tabs converted to spaces for visual > here: > > if (HAS_PCH_DG1(dev_priv)) > invert_bits = INVERT_DDIA_HPD | > INVERT_DDIB_HPD | > INVERT_DDIC_HPD | > INVERT_DDID_HPD; > > Anyway, indentation isn't a very fruitful conversation in itself. The > original nitpick was an off the cuff remark. I'm mostly trying to > suggest to use tools that will do indentation and other things for you, > so you don't have to worry about getting it right. > Thank you for the tips! I find them very helpful. I'll make sure to use proper style when sending a new version. -- Gustavo Sousa
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index de06f293e173..c53d21ae197f 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -3263,6 +3263,21 @@ static void cherryview_irq_reset(struct drm_i915_private *dev_priv) spin_unlock_irq(&dev_priv->irq_lock); } +static void setup_hotplug_inversion(struct drm_i915_private *dev_priv) +{ + u32 invert_bits; + + if (HAS_PCH_DG1(dev_priv)) + invert_bits = INVERT_DDIA_HPD | + INVERT_DDIB_HPD | + INVERT_DDIC_HPD | + INVERT_DDID_HPD; + else + return; + + intel_uncore_rmw(&dev_priv->uncore, SOUTH_CHICKEN1, 0, invert_bits); +} + static u32 ibx_hotplug_enables(struct drm_i915_private *i915, enum hpd_pin pin) { @@ -3413,15 +3428,7 @@ static u32 gen11_hotplug_enables(struct drm_i915_private *i915, static void dg1_hpd_irq_setup(struct drm_i915_private *dev_priv) { - u32 val; - - val = intel_uncore_read(&dev_priv->uncore, SOUTH_CHICKEN1); - val |= (INVERT_DDIA_HPD | - INVERT_DDIB_HPD | - INVERT_DDIC_HPD | - INVERT_DDID_HPD); - intel_uncore_write(&dev_priv->uncore, SOUTH_CHICKEN1, val); - + setup_hotplug_inversion(dev_priv); icp_hpd_irq_setup(dev_priv); }
Make the code more readable, which will be more apparent as new platforms with different hotplug inversion needs are added. Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com> --- drivers/gpu/drm/i915/i915_irq.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-)