[Intel-gfx] [PATCH v26 2/9] drm/i915: Use bw state for per crtc SAGV evaluation
Lisovskiy, Stanislav
stanislav.lisovskiy at intel.com
Thu Apr 30 10:14:57 UTC 2020
On Thu, Apr 30, 2020 at 01:08:20PM +0300, Ville Syrjälä wrote:
> On Thu, Apr 30, 2020 at 12:52:42PM +0300, Lisovskiy, Stanislav wrote:
> > On Thu, Apr 30, 2020 at 12:25:38PM +0300, Ville Syrjälä wrote:
> > > On Thu, Apr 30, 2020 at 12:13:35PM +0300, Lisovskiy, Stanislav wrote:
> > > > On Thu, Apr 30, 2020 at 12:09:22PM +0300, Ville Syrjälä wrote:
> > > > > On Thu, Apr 23, 2020 at 10:58:55AM +0300, Stanislav Lisovskiy wrote:
> > > > > > Future platforms require per-crtc SAGV evaluation
> > > > > > and serializing global state when those are changed
> > > > > > from different commits.
> > > > > >
> > > > > > v2: - Add has_sagv check to intel_crtc_can_enable_sagv
> > > > > > so that it sets bit in reject mask.
> > > > > > - Use bw_state in intel_pre/post_plane_enable_sagv
> > > > > > instead of atomic state
> > > > > >
> > > > > > v3: - Fixed rebase conflict, now using
> > > > > > intel_atomic_crtc_state_for_each_plane_state in
> > > > > > order to call it from atomic check
> > > > > > v4: - Use fb modifier from plane state
> > > > > >
> > > > > > v5: - Make intel_has_sagv static again(Ville)
> > > > > > - Removed unnecessary NULL assignments(Ville)
> > > > > > - Removed unnecessary SAGV debug(Ville)
> > > > > > - Call intel_compute_sagv_mask only for modesets(Ville)
> > > > > > - Serialize global state only if sagv results change, but
> > > > > > not mask itself(Ville)
> > > > > >
> > > > > > v6: - use lock global state instead of serialize(Ville)
> > > > >
> > > > > What I meant is that we need both. Serialize if sagv state is going to
> > > > > change, otherwise lock if the mask changes.
> > > >
> > > > As I understand whenever we modify global state but not a real hw, we do
> > > > only global state locking - pipe sagv mask is not actually a hw, but just
> > > > a virtual thing. It affects the QGV points we enable and if it happens to
> > > > affect those in a way that those change - we'll any way have serialize
> > > > called from intel_bw.c. Thus shouldn't be an issue.
> > >
> > > I don't like the code to rely on magic happening elsewhere. IMO
> > > it just makes it hard to reason about the logic when you have
> > > constantly remind youself what may or may not happen some other
> > > piece of code. Also we don't even have qgv points on all the
> > > platforms, so presumably we may not even excute that other
> > > piece of code always?
> >
> > Agree, sounds reasonable. Would be cool may be to unite both serialize
> > and global state locking, under some helper function, so that same
> > code snippet is not copy-paste all over the place.
> >
> > like intel_lock_or_serialize_state(state, bool global_state_changed, bool hw_state_changed)
>
> intel_lock_or_serialize_state(state,
> a != b,
> x != y);
>
> doesn't really make the intent clear at all. So not really in favor of a
> function that takes two booleans.
bool global_state_changed = new_sagv_pipe_mask != old_sagv_pipe_mask;
bool hw_state_changed = new_can_enable_sagv != old_can_enable_sagv;
intel_lock_or_serialize(state, global_state_changed, hw_state_changed);
I think together with proper comment this looks pretty clear and also
eliminates the need in duplicating conditions all over the place.
Just a proposal though.
Stan
>
> >
> > Stan
> >
> > >
> > > >
> > > > I can change it anyway of course.
> > > >
> > > > Stan
> > > >
> > > > >
> > > > > >
> > > > > > Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>
> > > > > > Cc: Ville Syrjälä <ville.syrjala at intel.com>
> > > > > > Cc: James Ausmus <james.ausmus at intel.com>
> > > > > > ---
> > > > > > drivers/gpu/drm/i915/display/intel_bw.h | 6 ++
> > > > > > drivers/gpu/drm/i915/intel_pm.c | 113 ++++++++++++++++++------
> > > > > > drivers/gpu/drm/i915/intel_pm.h | 3 +-
> > > > > > 3 files changed, 93 insertions(+), 29 deletions(-)
> > > > > >
> > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_bw.h b/drivers/gpu/drm/i915/display/intel_bw.h
> > > > > > index ac004d6f4276..d6df91058223 100644
> > > > > > --- a/drivers/gpu/drm/i915/display/intel_bw.h
> > > > > > +++ b/drivers/gpu/drm/i915/display/intel_bw.h
> > > > > > @@ -18,6 +18,12 @@ struct intel_crtc_state;
> > > > > > struct intel_bw_state {
> > > > > > struct intel_global_state base;
> > > > > >
> > > > > > + /*
> > > > > > + * Contains a bit mask, used to determine, whether correspondent
> > > > > > + * pipe allows SAGV or not.
> > > > > > + */
> > > > > > + u8 pipe_sagv_reject;
> > > > > > +
> > > > > > unsigned int data_rate[I915_MAX_PIPES];
> > > > > > u8 num_active_planes[I915_MAX_PIPES];
> > > > > > };
> > > > > > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> > > > > > index 338a82577b76..7e15cf3368ad 100644
> > > > > > --- a/drivers/gpu/drm/i915/intel_pm.c
> > > > > > +++ b/drivers/gpu/drm/i915/intel_pm.c
> > > > > > @@ -43,6 +43,7 @@
> > > > > > #include "i915_fixed.h"
> > > > > > #include "i915_irq.h"
> > > > > > #include "i915_trace.h"
> > > > > > +#include "display/intel_bw.h"
> > > > > > #include "intel_pm.h"
> > > > > > #include "intel_sideband.h"
> > > > > > #include "../../../platform/x86/intel_ips.h"
> > > > > > @@ -3760,34 +3761,75 @@ intel_disable_sagv(struct drm_i915_private *dev_priv)
> > > > > > void intel_sagv_pre_plane_update(struct intel_atomic_state *state)
> > > > > > {
> > > > > > struct drm_i915_private *dev_priv = to_i915(state->base.dev);
> > > > > > + const struct intel_bw_state *new_bw_state;
> > > > > >
> > > > > > - if (!intel_can_enable_sagv(state))
> > > > > > + /*
> > > > > > + * Just return if we can't control SAGV or don't have it.
> > > > > > + * This is different from situation when we have SAGV but just can't
> > > > > > + * afford it due to DBuf limitation - in case if SAGV is completely
> > > > > > + * disabled in a BIOS, we are not even allowed to send a PCode request,
> > > > > > + * as it will throw an error. So have to check it here.
> > > > > > + */
> > > > > > + if (!intel_has_sagv(dev_priv))
> > > > > > + return;
> > > > > > +
> > > > > > + new_bw_state = intel_atomic_get_new_bw_state(state);
> > > > > > + if (!new_bw_state)
> > > > > > + return;
> > > > > > +
> > > > > > + if (!intel_can_enable_sagv(new_bw_state))
> > > > > > intel_disable_sagv(dev_priv);
> > > > > > }
> > > > > >
> > > > > > void intel_sagv_post_plane_update(struct intel_atomic_state *state)
> > > > > > {
> > > > > > struct drm_i915_private *dev_priv = to_i915(state->base.dev);
> > > > > > + const struct intel_bw_state *new_bw_state;
> > > > > >
> > > > > > - if (intel_can_enable_sagv(state))
> > > > > > + /*
> > > > > > + * Just return if we can't control SAGV or don't have it.
> > > > > > + * This is different from situation when we have SAGV but just can't
> > > > > > + * afford it due to DBuf limitation - in case if SAGV is completely
> > > > > > + * disabled in a BIOS, we are not even allowed to send a PCode request,
> > > > > > + * as it will throw an error. So have to check it here.
> > > > > > + */
> > > > > > + if (!intel_has_sagv(dev_priv))
> > > > > > + return;
> > > > > > +
> > > > > > + new_bw_state = intel_atomic_get_new_bw_state(state);
> > > > > > + if (!new_bw_state)
> > > > > > + return;
> > > > > > +
> > > > > > + if (intel_can_enable_sagv(new_bw_state))
> > > > > > intel_enable_sagv(dev_priv);
> > > > > > }
> > > > > >
> > > > > > static bool intel_crtc_can_enable_sagv(const struct intel_crtc_state *crtc_state)
> > > > > > {
> > > > > > - struct drm_device *dev = crtc_state->uapi.crtc->dev;
> > > > > > - struct drm_i915_private *dev_priv = to_i915(dev);
> > > > > > + struct intel_atomic_state *state = to_intel_atomic_state(crtc_state->uapi.state);
> > > > > > struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> > > > > > + struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
> > > > > > struct intel_plane *plane;
> > > > > > + const struct intel_plane_state *plane_state;
> > > > > > int level, latency;
> > > > > >
> > > > > > + if (!intel_has_sagv(dev_priv))
> > > > > > + return false;
> > > > > > +
> > > > > > if (!crtc_state->hw.active)
> > > > > > return true;
> > > > > >
> > > > > > + /*
> > > > > > + * SKL+ workaround: bspec recommends we disable SAGV when we have
> > > > > > + * more then one pipe enabled
> > > > > > + */
> > > > > > + if (hweight8(state->active_pipes) > 1)
> > > > > > + return false;
> > > > > > +
> > > > > > if (crtc_state->hw.adjusted_mode.flags & DRM_MODE_FLAG_INTERLACE)
> > > > > > return false;
> > > > > >
> > > > > > - for_each_intel_plane_on_crtc(dev, crtc, plane) {
> > > > > > + intel_atomic_crtc_state_for_each_plane_state(plane, plane_state, crtc_state) {
> > > > > > const struct skl_plane_wm *wm =
> > > > > > &crtc_state->wm.skl.optimal.planes[plane->id];
> > > > > >
> > > > > > @@ -3803,7 +3845,7 @@ static bool intel_crtc_can_enable_sagv(const struct intel_crtc_state *crtc_state
> > > > > > latency = dev_priv->wm.skl_latency[level];
> > > > > >
> > > > > > if (skl_needs_memory_bw_wa(dev_priv) &&
> > > > > > - plane->base.state->fb->modifier ==
> > > > > > + plane_state->uapi.fb->modifier ==
> > > > > > I915_FORMAT_MOD_X_TILED)
> > > > > > latency += 15;
> > > > > >
> > > > > > @@ -3819,35 +3861,44 @@ static bool intel_crtc_can_enable_sagv(const struct intel_crtc_state *crtc_state
> > > > > > return true;
> > > > > > }
> > > > > >
> > > > > > -bool intel_can_enable_sagv(struct intel_atomic_state *state)
> > > > > > +bool intel_can_enable_sagv(const struct intel_bw_state *bw_state)
> > > > > > {
> > > > > > - struct drm_i915_private *dev_priv = to_i915(state->base.dev);
> > > > > > + return bw_state->pipe_sagv_reject == 0;
> > > > > > +}
> > > > > > +
> > > > > > +static int intel_compute_sagv_mask(struct intel_atomic_state *state)
> > > > > > +{
> > > > > > + int ret;
> > > > > > struct intel_crtc *crtc;
> > > > > > - const struct intel_crtc_state *crtc_state;
> > > > > > - enum pipe pipe;
> > > > > > + struct intel_crtc_state *new_crtc_state;
> > > > > > + struct intel_bw_state *new_bw_state = NULL;
> > > > > > + const struct intel_bw_state *old_bw_state = NULL;
> > > > > > + int i;
> > > > > >
> > > > > > - if (!intel_has_sagv(dev_priv))
> > > > > > - return false;
> > > > > > + for_each_new_intel_crtc_in_state(state, crtc,
> > > > > > + new_crtc_state, i) {
> > > > > > + new_bw_state = intel_atomic_get_bw_state(state);
> > > > > > + if (IS_ERR(new_bw_state))
> > > > > > + return PTR_ERR(new_bw_state);
> > > > > >
> > > > > > - /*
> > > > > > - * If there are no active CRTCs, no additional checks need be performed
> > > > > > - */
> > > > > > - if (hweight8(state->active_pipes) == 0)
> > > > > > - return true;
> > > > > > + old_bw_state = intel_atomic_get_old_bw_state(state);
> > > > > >
> > > > > > - /*
> > > > > > - * SKL+ workaround: bspec recommends we disable SAGV when we have
> > > > > > - * more then one pipe enabled
> > > > > > - */
> > > > > > - if (hweight8(state->active_pipes) > 1)
> > > > > > - return false;
> > > > > > + if (intel_crtc_can_enable_sagv(new_crtc_state))
> > > > > > + new_bw_state->pipe_sagv_reject &= ~BIT(crtc->pipe);
> > > > > > + else
> > > > > > + new_bw_state->pipe_sagv_reject |= BIT(crtc->pipe);
> > > > > > + }
> > > > > >
> > > > > > - /* Since we're now guaranteed to only have one active CRTC... */
> > > > > > - pipe = ffs(state->active_pipes) - 1;
> > > > > > - crtc = intel_get_crtc_for_pipe(dev_priv, pipe);
> > > > > > - crtc_state = to_intel_crtc_state(crtc->base.state);
> > > > > > + if (!new_bw_state)
> > > > > > + return 0;
> > > > > >
> > > > > > - return intel_crtc_can_enable_sagv(crtc_state);
> > > > > > + if (intel_can_enable_sagv(new_bw_state) != intel_can_enable_sagv(old_bw_state)) {
> > > > > > + ret = intel_atomic_lock_global_state(&new_bw_state->base);
> > > > > > + if (ret)
> > > > > > + return ret;
> > > > > > + }
> > > > > > +
> > > > > > + return 0;
> > > > > > }
> > > > > >
> > > > > > /*
> > > > > > @@ -5860,6 +5911,12 @@ skl_compute_wm(struct intel_atomic_state *state)
> > > > > > if (ret)
> > > > > > return ret;
> > > > > >
> > > > > > + if (state->modeset) {
> > > > > > + ret = intel_compute_sagv_mask(state);
> > > > > > + if (ret)
> > > > > > + return ret;
> > > > > > + }
> > > > > > +
> > > > > > /*
> > > > > > * skl_compute_ddb() will have adjusted the final watermarks
> > > > > > * based on how much ddb is available. Now we can actually
> > > > > > diff --git a/drivers/gpu/drm/i915/intel_pm.h b/drivers/gpu/drm/i915/intel_pm.h
> > > > > > index 9a6036ab0f90..fd1dc422e6c5 100644
> > > > > > --- a/drivers/gpu/drm/i915/intel_pm.h
> > > > > > +++ b/drivers/gpu/drm/i915/intel_pm.h
> > > > > > @@ -9,6 +9,7 @@
> > > > > > #include <linux/types.h>
> > > > > >
> > > > > > #include "i915_reg.h"
> > > > > > +#include "display/intel_bw.h"
> > > > > >
> > > > > > struct drm_device;
> > > > > > struct drm_i915_private;
> > > > > > @@ -41,7 +42,7 @@ void skl_pipe_wm_get_hw_state(struct intel_crtc *crtc,
> > > > > > struct skl_pipe_wm *out);
> > > > > > void g4x_wm_sanitize(struct drm_i915_private *dev_priv);
> > > > > > void vlv_wm_sanitize(struct drm_i915_private *dev_priv);
> > > > > > -bool intel_can_enable_sagv(struct intel_atomic_state *state);
> > > > > > +bool intel_can_enable_sagv(const struct intel_bw_state *bw_state);
> > > > > > int intel_enable_sagv(struct drm_i915_private *dev_priv);
> > > > > > int intel_disable_sagv(struct drm_i915_private *dev_priv);
> > > > > > void intel_sagv_pre_plane_update(struct intel_atomic_state *state);
> > > > > > --
> > > > > > 2.24.1.485.gad05a3d8e5
> > > > >
> > > > > --
> > > > > Ville Syrjälä
> > > > > Intel
> > >
> > > --
> > > Ville Syrjälä
> > > Intel
>
> --
> Ville Syrjälä
> Intel
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