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From:   Rajat Jain <rajatja@google.com>
Date:   Thu, 5 Dec 2019 01:34:33 -0800
Message-ID: <CACK8Z6HSdPY3TZZ1vwsr7YBM63veFyVwQneG-XNSM_x6L1QiLw@mail.gmail.com>
Subject: Re: [PATCH v2 1/3] drm/i915: Move the code to populate ACPI device ID
 into intel_acpi
To:     Jani Nikula <jani.nikula@linux.intel.com>
Cc:     Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Sean Paul <sean@poorly.run>, David Airlie <airlied@linux.ie>,
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        Rodrigo Vivi <rodrigo.vivi@intel.com>,
        =?UTF-8?B?VmlsbGUgU3lyasOkbMOk?= <ville.syrjala@linux.intel.com>,
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        Duncan Laurie <dlaurie@google.com>,
        Jesse Barnes <jsbarnes@google.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        Rajat Jain <rajatxjain@gmail.com>
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Hi Jani,

Thanks for the review.

On Wed, Nov 20, 2019 at 6:41 AM Jani Nikula <jani.nikula@linux.intel.com> wrote:
>
> On Mon, 04 Nov 2019, Rajat Jain <rajatja@google.com> wrote:
> > Move the code that populates the ACPI device ID for devices, into
> > more appripriate intel_acpi.c. This is done in preparation for more
> > users of this code (in next patch).
>
> I don't think your use of the code makes sense (I'll explain in reply to
> the other patches)

OK, I'll discuss this there.

> but I could be persuaded to move the code to
> intel_acpi.c.
>
> > Signed-off-by: Rajat Jain <rajatja@google.com>
> > Change-Id: Ifb3bd458734985c2a78ba682e6f0a2e63e0626ca
>
> Please drop Change-Ids.

Done.

>
> > ---
> > v2: v1 doesn't exist. Found existing code in i915 driver to assign the ACPI ID
> >     which is what I plan to re-use.
> >
> >
> >  drivers/gpu/drm/i915/display/intel_acpi.c     | 87 +++++++++++++++++++
> >  drivers/gpu/drm/i915/display/intel_acpi.h     |  6 ++
> >  drivers/gpu/drm/i915/display/intel_opregion.c | 80 +----------------
> >  3 files changed, 97 insertions(+), 76 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_acpi.c b/drivers/gpu/drm/i915/display/intel_acpi.c
> > index 3456d33feb46..748d9b3125dd 100644
> > --- a/drivers/gpu/drm/i915/display/intel_acpi.c
> > +++ b/drivers/gpu/drm/i915/display/intel_acpi.c
> > @@ -156,3 +156,90 @@ void intel_register_dsm_handler(void)
> >  void intel_unregister_dsm_handler(void)
> >  {
> >  }
> > +
> > +/*
> > + * ACPI Specification, Revision 5.0, Appendix B.3.2 _DOD (Enumerate All Devices
> > + * Attached to the Display Adapter).
> > + */
> > +#define ACPI_DISPLAY_INDEX_SHIFT             0
> > +#define ACPI_DISPLAY_INDEX_MASK                      (0xf << 0)
> > +#define ACPI_DISPLAY_PORT_ATTACHMENT_SHIFT   4
> > +#define ACPI_DISPLAY_PORT_ATTACHMENT_MASK    (0xf << 4)
> > +#define ACPI_DISPLAY_TYPE_SHIFT                      8
> > +#define ACPI_DISPLAY_TYPE_MASK                       (0xf << 8)
> > +#define ACPI_DISPLAY_TYPE_OTHER                      (0 << 8)
> > +#define ACPI_DISPLAY_TYPE_VGA                        (1 << 8)
> > +#define ACPI_DISPLAY_TYPE_TV                 (2 << 8)
> > +#define ACPI_DISPLAY_TYPE_EXTERNAL_DIGITAL   (3 << 8)
> > +#define ACPI_DISPLAY_TYPE_INTERNAL_DIGITAL   (4 << 8)
> > +#define ACPI_VENDOR_SPECIFIC_SHIFT           12
> > +#define ACPI_VENDOR_SPECIFIC_MASK            (0xf << 12)
> > +#define ACPI_BIOS_CAN_DETECT                 (1 << 16)
> > +#define ACPI_DEPENDS_ON_VGA                  (1 << 17)
> > +#define ACPI_PIPE_ID_SHIFT                   18
> > +#define ACPI_PIPE_ID_MASK                    (7 << 18)
> > +#define ACPI_DEVICE_ID_SCHEME                        (1ULL << 31)
> > +
> > +static u32 acpi_display_type(struct intel_connector *connector)
> > +{
> > +     u32 display_type;
> > +
> > +     switch (connector->base.connector_type) {
> > +     case DRM_MODE_CONNECTOR_VGA:
> > +     case DRM_MODE_CONNECTOR_DVIA:
> > +             display_type = ACPI_DISPLAY_TYPE_VGA;
> > +             break;
> > +     case DRM_MODE_CONNECTOR_Composite:
> > +     case DRM_MODE_CONNECTOR_SVIDEO:
> > +     case DRM_MODE_CONNECTOR_Component:
> > +     case DRM_MODE_CONNECTOR_9PinDIN:
> > +     case DRM_MODE_CONNECTOR_TV:
> > +             display_type = ACPI_DISPLAY_TYPE_TV;
> > +             break;
> > +     case DRM_MODE_CONNECTOR_DVII:
> > +     case DRM_MODE_CONNECTOR_DVID:
> > +     case DRM_MODE_CONNECTOR_DisplayPort:
> > +     case DRM_MODE_CONNECTOR_HDMIA:
> > +     case DRM_MODE_CONNECTOR_HDMIB:
> > +             display_type = ACPI_DISPLAY_TYPE_EXTERNAL_DIGITAL;
> > +             break;
> > +     case DRM_MODE_CONNECTOR_LVDS:
> > +     case DRM_MODE_CONNECTOR_eDP:
> > +     case DRM_MODE_CONNECTOR_DSI:
> > +             display_type = ACPI_DISPLAY_TYPE_INTERNAL_DIGITAL;
> > +             break;
> > +     case DRM_MODE_CONNECTOR_Unknown:
> > +     case DRM_MODE_CONNECTOR_VIRTUAL:
> > +             display_type = ACPI_DISPLAY_TYPE_OTHER;
> > +             break;
> > +     default:
> > +             MISSING_CASE(connector->base.connector_type);
> > +             display_type = ACPI_DISPLAY_TYPE_OTHER;
> > +             break;
> > +     }
> > +
> > +     return display_type;
> > +}
> > +
> > +void intel_populate_acpi_ids_for_all_connectors(struct drm_device *drm_dev)
>
> Plase use intel_foo_ prefix for functions in intel_foo.c,
> i.e. intel_acpi_ here. Say, intel_acpi_device_id_update() or something.

Done.

>
> Please always prefer struct drm_i915_private *i915 over struct
> drm_device * pointers in i915 code.

Done

>
> > +{
> > +     struct intel_connector *connector;
> > +     struct drm_connector_list_iter conn_iter;
> > +     u8 display_index[16] = {};
> > +     u32 device_id, type;
> > +
> > +     /* Populate the ACPI IDs for all connectors for a given drm_device */
> > +     drm_connector_list_iter_begin(drm_dev, &conn_iter);
> > +     for_each_intel_connector_iter(connector, &conn_iter) {
> > +
>
> Superfluous newline, the device_id and type local vars could be here as
> in the original.

Done.

>
> > +             device_id = acpi_display_type(connector);
> > +
> > +             /* Use display type specific display index. */
> > +             type = (device_id & ACPI_DISPLAY_TYPE_MASK)
> > +                     >> ACPI_DISPLAY_TYPE_SHIFT;
> > +             device_id |= display_index[type]++ << ACPI_DISPLAY_INDEX_SHIFT;
> > +
> > +             connector->acpi_device_id = device_id;
> > +     }
> > +     drm_connector_list_iter_end(&conn_iter);
> > +}
> > diff --git a/drivers/gpu/drm/i915/display/intel_acpi.h b/drivers/gpu/drm/i915/display/intel_acpi.h
> > index 1c576b3fb712..8f6d850df6fa 100644
> > --- a/drivers/gpu/drm/i915/display/intel_acpi.h
> > +++ b/drivers/gpu/drm/i915/display/intel_acpi.h
> > @@ -6,12 +6,18 @@
> >  #ifndef __INTEL_ACPI_H__
> >  #define __INTEL_ACPI_H__
> >
> > +#include "intel_display_types.h"
> > +
>
> Please prefer forward declarations over adding new includes.
>
> struct drm_i915_private;
>

Done.

> >  #ifdef CONFIG_ACPI
> >  void intel_register_dsm_handler(void);
> >  void intel_unregister_dsm_handler(void);
> > +void intel_populate_acpi_ids_for_all_connectors(struct drm_device *drm_dev);
> >  #else
> >  static inline void intel_register_dsm_handler(void) { return; }
> >  static inline void intel_unregister_dsm_handler(void) { return; }
> > +static inline void
> > +static inline void
>
> Whoops.

Done.

>
> > +intel_populate_acpi_ids_for_all_connectors(struct drm_device *drm_dev) { }
> >  #endif /* CONFIG_ACPI */
> >
> >  #endif /* __INTEL_ACPI_H__ */
> > diff --git a/drivers/gpu/drm/i915/display/intel_opregion.c b/drivers/gpu/drm/i915/display/intel_opregion.c
> > index 969ade623691..f5976a6ab3c4 100644
> > --- a/drivers/gpu/drm/i915/display/intel_opregion.c
> > +++ b/drivers/gpu/drm/i915/display/intel_opregion.c
> > @@ -35,6 +35,7 @@
> >  #include "display/intel_panel.h"
> >
> >  #include "i915_drv.h"
> > +#include "intel_acpi.h"
> >  #include "intel_display_types.h"
> >  #include "intel_opregion.h"
> >
> > @@ -242,29 +243,6 @@ struct opregion_asle_ext {
> >  #define SWSCI_SBCB_POST_VBE_PM               SWSCI_FUNCTION_CODE(SWSCI_SBCB, 19)
> >  #define SWSCI_SBCB_ENABLE_DISABLE_AUDIO      SWSCI_FUNCTION_CODE(SWSCI_SBCB, 21)
> >
> > -/*
> > - * ACPI Specification, Revision 5.0, Appendix B.3.2 _DOD (Enumerate All Devices
> > - * Attached to the Display Adapter).
> > - */
> > -#define ACPI_DISPLAY_INDEX_SHIFT             0
> > -#define ACPI_DISPLAY_INDEX_MASK                      (0xf << 0)
> > -#define ACPI_DISPLAY_PORT_ATTACHMENT_SHIFT   4
> > -#define ACPI_DISPLAY_PORT_ATTACHMENT_MASK    (0xf << 4)
> > -#define ACPI_DISPLAY_TYPE_SHIFT                      8
> > -#define ACPI_DISPLAY_TYPE_MASK                       (0xf << 8)
> > -#define ACPI_DISPLAY_TYPE_OTHER                      (0 << 8)
> > -#define ACPI_DISPLAY_TYPE_VGA                        (1 << 8)
> > -#define ACPI_DISPLAY_TYPE_TV                 (2 << 8)
> > -#define ACPI_DISPLAY_TYPE_EXTERNAL_DIGITAL   (3 << 8)
> > -#define ACPI_DISPLAY_TYPE_INTERNAL_DIGITAL   (4 << 8)
> > -#define ACPI_VENDOR_SPECIFIC_SHIFT           12
> > -#define ACPI_VENDOR_SPECIFIC_MASK            (0xf << 12)
> > -#define ACPI_BIOS_CAN_DETECT                 (1 << 16)
> > -#define ACPI_DEPENDS_ON_VGA                  (1 << 17)
> > -#define ACPI_PIPE_ID_SHIFT                   18
> > -#define ACPI_PIPE_ID_MASK                    (7 << 18)
> > -#define ACPI_DEVICE_ID_SCHEME                        (1 << 31)
> > -
> >  #define MAX_DSLP     1500
> >
> >  static int swsci(struct drm_i915_private *dev_priv,
> > @@ -662,54 +640,12 @@ static void set_did(struct intel_opregion *opregion, int i, u32 val)
> >       }
> >  }
> >
> > -static u32 acpi_display_type(struct intel_connector *connector)
> > -{
> > -     u32 display_type;
> > -
> > -     switch (connector->base.connector_type) {
> > -     case DRM_MODE_CONNECTOR_VGA:
> > -     case DRM_MODE_CONNECTOR_DVIA:
> > -             display_type = ACPI_DISPLAY_TYPE_VGA;
> > -             break;
> > -     case DRM_MODE_CONNECTOR_Composite:
> > -     case DRM_MODE_CONNECTOR_SVIDEO:
> > -     case DRM_MODE_CONNECTOR_Component:
> > -     case DRM_MODE_CONNECTOR_9PinDIN:
> > -     case DRM_MODE_CONNECTOR_TV:
> > -             display_type = ACPI_DISPLAY_TYPE_TV;
> > -             break;
> > -     case DRM_MODE_CONNECTOR_DVII:
> > -     case DRM_MODE_CONNECTOR_DVID:
> > -     case DRM_MODE_CONNECTOR_DisplayPort:
> > -     case DRM_MODE_CONNECTOR_HDMIA:
> > -     case DRM_MODE_CONNECTOR_HDMIB:
> > -             display_type = ACPI_DISPLAY_TYPE_EXTERNAL_DIGITAL;
> > -             break;
> > -     case DRM_MODE_CONNECTOR_LVDS:
> > -     case DRM_MODE_CONNECTOR_eDP:
> > -     case DRM_MODE_CONNECTOR_DSI:
> > -             display_type = ACPI_DISPLAY_TYPE_INTERNAL_DIGITAL;
> > -             break;
> > -     case DRM_MODE_CONNECTOR_Unknown:
> > -     case DRM_MODE_CONNECTOR_VIRTUAL:
> > -             display_type = ACPI_DISPLAY_TYPE_OTHER;
> > -             break;
> > -     default:
> > -             MISSING_CASE(connector->base.connector_type);
> > -             display_type = ACPI_DISPLAY_TYPE_OTHER;
> > -             break;
> > -     }
> > -
> > -     return display_type;
> > -}
> > -
> >  static void intel_didl_outputs(struct drm_i915_private *dev_priv)
> >  {
> >       struct intel_opregion *opregion = &dev_priv->opregion;
> >       struct intel_connector *connector;
> >       struct drm_connector_list_iter conn_iter;
> >       int i = 0, max_outputs;
> > -     int display_index[16] = {};
> >
> >       /*
> >        * In theory, did2, the extended didl, gets added at opregion version
> > @@ -721,20 +657,12 @@ static void intel_didl_outputs(struct drm_i915_private *dev_priv)
> >       max_outputs = ARRAY_SIZE(opregion->acpi->didl) +
> >               ARRAY_SIZE(opregion->acpi->did2);
> >
> > +     intel_populate_acpi_ids_for_all_connectors(&dev_priv->drm);
> > +
>
> As the acpi_device_ids will be used elsewhere too, maybe this call needs
> to be moved to a higher level and called on the resume path. *shrug*

I don't understand this code well, happy to do whatever you or others
see fit. I kept it here so as to not to disturb any code that I do not
understand and cause unintended regressions (this code had it here, so
decided to leave it as-is). For the privacy screen purposes, we just
need to know the ACPI ID before we probe for the privacy screen to add
the property.

Thanks,

Rajat


>
> BR,
> Jani.
>
> >       drm_connector_list_iter_begin(&dev_priv->drm, &conn_iter);
> >       for_each_intel_connector_iter(connector, &conn_iter) {
> > -             u32 device_id, type;
> > -
> > -             device_id = acpi_display_type(connector);
> > -
> > -             /* Use display type specific display index. */
> > -             type = (device_id & ACPI_DISPLAY_TYPE_MASK)
> > -                     >> ACPI_DISPLAY_TYPE_SHIFT;
> > -             device_id |= display_index[type]++ << ACPI_DISPLAY_INDEX_SHIFT;
> > -
> > -             connector->acpi_device_id = device_id;
> >               if (i < max_outputs)
> > -                     set_did(opregion, i, device_id);
> > +                     set_did(opregion, i, connector->acpi_device_id);
> >               i++;
> >       }
> >       drm_connector_list_iter_end(&conn_iter);
>
> --
> Jani Nikula, Intel Open Source Graphics Center