Re: [PATCH v7 4/4] drm/i915: Add support for integrated privacy screen

From: Rajat Jain
Date: Thu Mar 12 2020 - 01:55:57 EST


Hi Jani,

On Mon, Mar 9, 2020 at 5:18 PM Rajat Jain <rajatja@xxxxxxxxxx> wrote:
>
> Hi Jani,
>
> I have 1 question / need 1 help about this patch:

Kind ignore, I found the answer, and posted my new patchset here:
https://patchwork.freedesktop.org/series/74607/

I got a "failed to apply" email from the patchwork. Can you please let
me know on which branch is it trying to apply it? I have currently
rebased my patchset to drm-intel-next-queued.

Thanks & Best Regards,

Rajat

>
> On Mon, Mar 9, 2020 at 5:06 PM Rajat Jain <rajatja@xxxxxxxxxx> wrote:
> >
> > Add support for an ACPI based integrated privacy screen that is
> > available on some systems.
> >
> > Signed-off-by: Rajat Jain <rajatja@xxxxxxxxxx>
> > ---
> > v7: * Move the privacy-screen property back into drm core.
> > * Do the actual HW EPS toggling at commit time.
> > * Provide a sample ACPI node for reference in comments.
> > v6: Always initialize prop in intel_attach_privacy_screen_property()
> > v5: fix a cosmetic checkpatch warning
> > v4: Fix a typo in intel_privacy_screen.h
> > v3: * Change license to GPL-2.0 OR MIT
> > * Move privacy screen enum from UAPI to intel_display_types.h
> > * Rename parameter name and some other minor changes.
> > v2: Formed by splitting the original patch into multiple patches.
> > - All code has been moved into i915 now.
> > - Privacy screen is a i915 property
> > - Have a local state variable to store the prvacy screen. Don't read
> > it from hardware.
> >
> > drivers/gpu/drm/i915/Makefile | 3 +-
> > drivers/gpu/drm/i915/display/intel_atomic.c | 1 +
> > drivers/gpu/drm/i915/display/intel_dp.c | 30 ++-
> > .../drm/i915/display/intel_privacy_screen.c | 175 ++++++++++++++++++
> > .../drm/i915/display/intel_privacy_screen.h | 27 +++
> > 5 files changed, 234 insertions(+), 2 deletions(-)
> > create mode 100644 drivers/gpu/drm/i915/display/intel_privacy_screen.c
> > create mode 100644 drivers/gpu/drm/i915/display/intel_privacy_screen.h
> >
> > diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
> > index 9f887a86e555d..da42389107f9c 100644
> > --- a/drivers/gpu/drm/i915/Makefile
> > +++ b/drivers/gpu/drm/i915/Makefile
> > @@ -209,7 +209,8 @@ i915-y += \
> > display/intel_vga.o
> > i915-$(CONFIG_ACPI) += \
> > display/intel_acpi.o \
> > - display/intel_opregion.o
> > + display/intel_opregion.o \
> > + display/intel_privacy_screen.o
> > i915-$(CONFIG_DRM_FBDEV_EMULATION) += \
> > display/intel_fbdev.o
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_atomic.c b/drivers/gpu/drm/i915/display/intel_atomic.c
> > index d043057d2fa03..fc6264b4a7f73 100644
> > --- a/drivers/gpu/drm/i915/display/intel_atomic.c
> > +++ b/drivers/gpu/drm/i915/display/intel_atomic.c
> > @@ -150,6 +150,7 @@ int intel_digital_connector_atomic_check(struct drm_connector *conn,
> > new_conn_state->base.picture_aspect_ratio != old_conn_state->base.picture_aspect_ratio ||
> > new_conn_state->base.content_type != old_conn_state->base.content_type ||
> > new_conn_state->base.scaling_mode != old_conn_state->base.scaling_mode ||
> > + new_conn_state->base.privacy_screen_status != old_conn_state->base.privacy_screen_status ||
> > !blob_equal(new_conn_state->base.hdr_output_metadata,
> > old_conn_state->base.hdr_output_metadata))
> > crtc_state->mode_changed = true;
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> > index 41c623b029464..a39b0c420b50a 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> > @@ -62,6 +62,7 @@
> > #include "intel_lspcon.h"
> > #include "intel_lvds.h"
> > #include "intel_panel.h"
> > +#include "intel_privacy_screen.h"
> > #include "intel_psr.h"
> > #include "intel_sideband.h"
> > #include "intel_tc.h"
> > @@ -5886,6 +5887,12 @@ intel_dp_connector_register(struct drm_connector *connector)
> > dev_priv->acpi_scan_done = true;
> > }
> >
> > + /* Check for integrated Privacy screen support */
> > + if (intel_privacy_screen_present(to_intel_connector(connector)))
> > + drm_connector_attach_privacy_screen_property(connector);
> > + else
> > + drm_connector_destroy_privacy_screen_property(connector);
> > +
> > DRM_DEBUG_KMS("registering %s bus for %s\n",
> > intel_dp->aux.name, connector->kdev->kobj.name);
> >
> > @@ -6881,9 +6888,30 @@ intel_dp_add_properties(struct intel_dp *intel_dp, struct drm_connector *connect
> > drm_connector_attach_scaling_mode_property(connector, allowed_scalers);
> >
> > connector->state->scaling_mode = DRM_MODE_SCALE_ASPECT;
> > +
> > + drm_connector_create_privacy_screen_property(connector);
> > }
> > }
> >
> > +static void intel_dp_update_privacy_screen(struct intel_encoder *encoder,
> > + const struct intel_crtc_state *crtc_state,
> > + const struct drm_connector_state *conn_state)
> > +{
> > + struct drm_connector *connector = conn_state->connector;
> > +
> > + if (connector->privacy_screen_property)
> > + intel_privacy_screen_set_val(to_intel_connector(connector),
> > + conn_state->privacy_screen_status);
> > +}
> > +
> > +static void intel_dp_update_pipe(struct intel_encoder *encoder,
> > + const struct intel_crtc_state *crtc_state,
> > + const struct drm_connector_state *conn_state)
> > +{
> > + intel_dp_update_privacy_screen(encoder, crtc_state, conn_state);
> > + intel_panel_update_backlight(encoder, crtc_state, conn_state);
> > +}
> > +
> > static void intel_dp_init_panel_power_timestamps(struct intel_dp *intel_dp)
> > {
> > intel_dp->panel_power_off_time = ktime_get_boottime();
> > @@ -7825,7 +7853,7 @@ bool intel_dp_init(struct drm_i915_private *dev_priv,
> > intel_encoder->compute_config = intel_dp_compute_config;
> > intel_encoder->get_hw_state = intel_dp_get_hw_state;
> > intel_encoder->get_config = intel_dp_get_config;
> > - intel_encoder->update_pipe = intel_panel_update_backlight;
> > + intel_encoder->update_pipe = intel_dp_update_pipe;
>
> For my testing purposes, I'm testing this using the proptest userspace utility
> in our distribution (I think from
> https://github.com/CPFL/drm/blob/master/tests/proptest/proptest.c). I
> notice that when I change the value of the property from userspace,
> even though the drm_connector_state->privacy_screen_status gets
> updated and reflects the change, the encoder->update_pipe() is not
> getting called. Just wanted to ask if this is expected since you seem
> to have implied that this update_pipe() might *not* get called if there *is* a
> full modeset? (What is the hook that gets called for a full modeset
> where i915 driver should commit this property change to the hardware?)
>
> Thanks a lot for all your help,
>
> Best Regards,
>
> Rajat
>
> > intel_encoder->suspend = intel_dp_encoder_suspend;
> > if (IS_CHERRYVIEW(dev_priv)) {
> > intel_encoder->pre_pll_enable = chv_dp_pre_pll_enable;
> > diff --git a/drivers/gpu/drm/i915/display/intel_privacy_screen.c b/drivers/gpu/drm/i915/display/intel_privacy_screen.c
> > new file mode 100644
> > index 0000000000000..6ff61ddf4c0a4
> > --- /dev/null
> > +++ b/drivers/gpu/drm/i915/display/intel_privacy_screen.c
> > @@ -0,0 +1,175 @@
> > +// SPDX-License-Identifier: GPL-2.0 OR MIT
> > +/*
> > + * Intel ACPI privacy screen code
> > + *
> > + * Copyright  2020 Google Inc.
> > + *
> > + * This code can help detect and control an integrated EPS (electronic
> > + * privacy screen) via ACPI functions. It expects an ACPI node for the
> > + * drm connector device with the following elements:
> > + *
> > + * UUID should be "c7033113-8720-4ceb-9090-9d52b3e52d73"
> > + *
> > + * _ADR = ACPI address per Spec (also see intel_acpi_device_id_update())
> > + * https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf
> > + * Pages 1119 - 1123.
> > + *
> > + * _DSM method that will perform the following functions according to
> > + * Local1 argument passed to it:
> > + * - Local1 = 0 (EPS capabilities): Report EPS presence and capabilities.
> > + * - Local1 = 1 (EPS State) : _DSM returns 1 if EPS is enabled, 0 otherwise.
> > + * - Local1 = 2 (EPS Enable) : _DSM enables EPS
> > + * - Local1 = 3 (EPS Disable): _DSM disables EPS
> > + *
> > + * Here is a sample ACPI node:
> > + *
> > + * Scope (\_SB.PCI0.GFX0) // Intel graphics device (PCI device)
> > + * {
> > + * Method (_DOD, 0, NotSerialized) // _DOD: Display Output Devices
> > + * {
> > + * Return (Package (0x01)
> > + * {
> > + * 0x80010400
> > + * })
> > + * }
> > + *
> > + * Device (LCD)
> > + * {
> > + * Name (_ADR, 0x80010400) // _ADR: Address
> > + * Name (_STA, 0x0F) // _STA: Status
> > + *
> > + * Method (EPSP, 0, NotSerialized) // EPS Present
> > + * {
> > + * Return (0x01)
> > + * }
> > + *
> > + * Method (EPSS, 0, NotSerialized) // EPS State
> > + * {
> > + * Local0 = \_SB.PCI0.GRXS (0xCD)
> > + * Return (Local0)
> > + * }
> > + *
> > + * Method (EPSE, 0, NotSerialized) // EPS Enable
> > + * {
> > + * \_SB.PCI0.STXS (0xCD)
> > + * }
> > + *
> > + * Method (EPSD, 0, NotSerialized) // EPS Disable
> > + * {
> > + * \_SB.PCI0.CTXS (0xCD)
> > + * }
> > + *
> > + * Method (_DSM, 4, Serialized) // _DSM: Device-Specific Method
> > + * {
> > + * ToBuffer (Arg0, Local0)
> > + * If ((Local0 == ToUUID ("c7033113-8720-4ceb-9090-9d52b3e52d73")))
> > + * {
> > + * ToInteger (Arg2, Local1)
> > + * If ((Local1 == Zero))
> > + * {
> > + * Local2 = EPSP ()
> > + * If ((Local2 == One))
> > + * {
> > + * Return (Buffer (One)
> > + * {
> > + * 0x0F
> > + * })
> > + * }
> > + * }
> > + *
> > + * If ((Local1 == One))
> > + * {
> > + * Return (EPSS ())
> > + * }
> > + *
> > + * If ((Local1 == 0x02))
> > + * {
> > + * EPSE ()
> > + * }
> > + *
> > + * If ((Local1 == 0x03))
> > + * {
> > + * EPSD ()
> > + * }
> > + *
> > + * Return (Buffer (One)
> > + * {
> > + * 0x00
> > + * })
> > + * }
> > + *
> > + * Return (Buffer (One)
> > + * {
> > + * 0x00
> > + * })
> > + * }
> > + * }
> > + * }
> > + */
> > +
> > +#include <linux/acpi.h>
> > +
> > +#include "intel_privacy_screen.h"
> > +
> > +#define CONNECTOR_DSM_REVID 1
> > +
> > +#define CONNECTOR_DSM_FN_PRIVACY_ENABLE 2
> > +#define CONNECTOR_DSM_FN_PRIVACY_DISABLE 3
> > +
> > +static const guid_t drm_conn_dsm_guid =
> > + GUID_INIT(0xC7033113, 0x8720, 0x4CEB,
> > + 0x90, 0x90, 0x9D, 0x52, 0xB3, 0xE5, 0x2D, 0x73);
> > +
> > +/* Makes _DSM call to set privacy screen status */
> > +static void acpi_privacy_screen_call_dsm(struct intel_connector *connector,
> > + u64 func)
> > +{
> > + union acpi_object *obj;
> > + acpi_handle acpi_handle = connector->acpi_handle;
> > +
> > + if (!acpi_handle)
> > + return;
> > +
> > + obj = acpi_evaluate_dsm(acpi_handle, &drm_conn_dsm_guid,
> > + CONNECTOR_DSM_REVID, func, NULL);
> > + if (!obj) {
> > + drm_err(connector->base.dev,
> > + "failed to evaluate _DSM for fn %llx\n", func);
> > + return;
> > + }
> > +
> > + ACPI_FREE(obj);
> > +}
> > +
> > +void intel_privacy_screen_set_val(struct intel_connector *connector,
> > + enum drm_privacy_screen_status val)
> > +{
> > + if (val == PRIVACY_SCREEN_DISABLED)
> > + acpi_privacy_screen_call_dsm(connector,
> > + CONNECTOR_DSM_FN_PRIVACY_DISABLE);
> > + else if (val == PRIVACY_SCREEN_ENABLED)
> > + acpi_privacy_screen_call_dsm(connector,
> > + CONNECTOR_DSM_FN_PRIVACY_ENABLE);
> > + else
> > + drm_err(connector->base.dev,
> > + "Cannot set privacy screen to invalid val %u\n", val);
> > +}
> > +
> > +bool intel_privacy_screen_present(struct intel_connector *connector)
> > +{
> > + acpi_handle handle = connector->acpi_handle;
> > +
> > + if (!handle)
> > + return false;
> > +
> > + if (!acpi_check_dsm(handle, &drm_conn_dsm_guid,
> > + CONNECTOR_DSM_REVID,
> > + 1 << CONNECTOR_DSM_FN_PRIVACY_ENABLE |
> > + 1 << CONNECTOR_DSM_FN_PRIVACY_DISABLE)) {
> > + drm_dbg_kms(connector->base.dev,
> > + "ACPI node but no privacy scrn\n");
> > + return false;
> > + }
> > + drm_info(connector->base.dev, "supports privacy screen\n");
> > + return true;
> > +}
> > diff --git a/drivers/gpu/drm/i915/display/intel_privacy_screen.h b/drivers/gpu/drm/i915/display/intel_privacy_screen.h
> > new file mode 100644
> > index 0000000000000..f8d2e246ea0bd
> > --- /dev/null
> > +++ b/drivers/gpu/drm/i915/display/intel_privacy_screen.h
> > @@ -0,0 +1,27 @@
> > +/* SPDX-License-Identifier: GPL-2.0 OR MIT */
> > +/*
> > + * Copyright  2019 Google Inc.
> > + */
> > +
> > +#ifndef __DRM_PRIVACY_SCREEN_H__
> > +#define __DRM_PRIVACY_SCREEN_H__
> > +
> > +#include "intel_display_types.h"
> > +
> > +#ifdef CONFIG_ACPI
> > +bool intel_privacy_screen_present(struct intel_connector *connector);
> > +void intel_privacy_screen_set_val(struct intel_connector *connector,
> > + enum drm_privacy_screen_status val);
> > +#else
> > +static bool intel_privacy_screen_present(struct intel_connector *connector)
> > +{
> > + return false;
> > +}
> > +
> > +static void
> > +intel_privacy_screen_set_val(struct intel_connector *connector,
> > + enum drm_privacy_screen_status val)
> > +{ }
> > +#endif /* CONFIG_ACPI */
> > +
> > +#endif /* __DRM_PRIVACY_SCREEN_H__ */
> > --
> > 2.25.1.481.gfbce0eb801-goog
> >