On Mon, Apr 26, 2021 at 11:24:10PM +0800, Kai-Heng Feng wrote: > On HP Fury G7 Workstations, graphics output is re-routed from Intel GFX > to discrete GFX after S3. This is not desirable, because userspace will > treat connected display as a new one, losing display settings. > > The expected behavior is to let discrete GFX drives all external > displays. > > The platform in question uses ACPI method \_SB.PCI0.HGME to enable MUX. > The method is inside the another _DSM, so add the _DSM and call it > accordingly. > > I also tested some MUX-less and iGPU only laptops with that _DSM, no > regression was found. > > v3: > - Remove BXT from names. > - Change the parameter type. > - Fold the function into intel_modeset_init_hw(). > > v2: > - Forward declare struct pci_dev. > > Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/3113 > References: https://lore.kernel.org/intel-gfx/1460040732-31417-4-git-send-email-animesh.manna@xxxxxxxxx/ > Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> > --- > drivers/gpu/drm/i915/display/intel_acpi.c | 18 ++++++++++++++++++ > drivers/gpu/drm/i915/display/intel_acpi.h | 3 +++ > drivers/gpu/drm/i915/display/intel_display.c | 2 ++ > 3 files changed, 23 insertions(+) > > diff --git a/drivers/gpu/drm/i915/display/intel_acpi.c b/drivers/gpu/drm/i915/display/intel_acpi.c > index 833d0c1be4f1..d008d3976261 100644 > --- a/drivers/gpu/drm/i915/display/intel_acpi.c > +++ b/drivers/gpu/drm/i915/display/intel_acpi.c > @@ -13,12 +13,17 @@ > #include "intel_display_types.h" > > #define INTEL_DSM_REVISION_ID 1 /* For Calpella anyway... */ > +#define INTEL_DSM_FN_PLATFORM_MUX_ENABLE 0 /* No args */ This block of defines is for the other DSM. We don't want to mix these up. We also want to name it according to the spec, so something like GET_BIOS_DATA_FUNCS_SUPPORTED. Similarly for the intel_dsm_enable_mux() wrapper function. + it needs a comment to document that some BIOSes abuse it to do MUX initialization and whatnot. We should perhaps rename all the old DSM stuff to something a bit less generic as well... > #define INTEL_DSM_FN_PLATFORM_MUX_INFO 1 /* No args */ > > static const guid_t intel_dsm_guid = > GUID_INIT(0x7ed873d3, 0xc2d0, 0x4e4f, > 0xa8, 0x54, 0x0f, 0x13, 0x17, 0xb0, 0x1c, 0x2c); > > +static const guid_t intel_dsm_guid2 = > + GUID_INIT(0x3e5b41c6, 0xeb1d, 0x4260, > + 0x9d, 0x15, 0xc7, 0x1f, 0xba, 0xda, 0xe4, 0x14); > + > static char *intel_dsm_port_name(u8 id) > { > switch (id) { > @@ -176,6 +181,19 @@ void intel_unregister_dsm_handler(void) > { > } > > +void intel_dsm_enable_mux(struct drm_i915_private *i915) > +{ > + struct pci_dev *pdev = i915->drm.pdev; > + acpi_handle dhandle; > + > + dhandle = ACPI_HANDLE(&pdev->dev); > + if (!dhandle) > + return; > + > + acpi_evaluate_dsm(dhandle, &intel_dsm_guid2, INTEL_DSM_REVISION_ID, > + INTEL_DSM_FN_PLATFORM_MUX_ENABLE, NULL); > +} > + > /* > * ACPI Specification, Revision 5.0, Appendix B.3.2 _DOD (Enumerate All Devices > * Attached to the Display Adapter). > diff --git a/drivers/gpu/drm/i915/display/intel_acpi.h b/drivers/gpu/drm/i915/display/intel_acpi.h > index e8b068661d22..def013cf6308 100644 > --- a/drivers/gpu/drm/i915/display/intel_acpi.h > +++ b/drivers/gpu/drm/i915/display/intel_acpi.h > @@ -11,11 +11,14 @@ struct drm_i915_private; > #ifdef CONFIG_ACPI > void intel_register_dsm_handler(void); > void intel_unregister_dsm_handler(void); > +void intel_dsm_enable_mux(struct drm_i915_private *i915); > void intel_acpi_device_id_update(struct drm_i915_private *i915); > #else > static inline void intel_register_dsm_handler(void) { return; } > static inline void intel_unregister_dsm_handler(void) { return; } > static inline > +void intel_dsm_enable_mux(struct drm_i915_private *i915) { return; } > +static inline > void intel_acpi_device_id_update(struct drm_i915_private *i915) { return; } > #endif /* CONFIG_ACPI */ > > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c > index a10e26380ef3..d79dae370b20 100644 > --- a/drivers/gpu/drm/i915/display/intel_display.c > +++ b/drivers/gpu/drm/i915/display/intel_display.c > @@ -11472,6 +11472,8 @@ void intel_modeset_init_hw(struct drm_i915_private *i915) > { > struct intel_cdclk_state *cdclk_state; > > + intel_dsm_enable_mux(i915); > + This should probably be somewhere around where we do all the other semi ACPI related init (OpRegion/etc.). > if (!HAS_DISPLAY(i915)) > return; > > -- > 2.30.2 -- Ville Syrjälä Intel
