On Tue, Sep 17, 2019 at 04:00:57PM +0300, Stanislav Lisovskiy wrote: > Added bandwidth calculation algorithm and checks, > similar way as it was done for ICL, some constants > were corrected according to BSpec.
Heh - I'd been working in this same area, and had some code written up, but your patch made it to the list first. :) > > Signed-off-by: Stanislav Lisovskiy <stanislav.lisovs...@intel.com> > > Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=111600 > --- > drivers/gpu/drm/i915/display/intel_bw.c | 108 +++++++++++++++++++++++- > 1 file changed, 107 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_bw.c > b/drivers/gpu/drm/i915/display/intel_bw.c > index 688858ebe4d0..e97d083f4f2a 100644 > --- a/drivers/gpu/drm/i915/display/intel_bw.c > +++ b/drivers/gpu/drm/i915/display/intel_bw.c > @@ -132,7 +132,8 @@ static int icl_sagv_max_dclk(const struct intel_qgv_info > *qi) > } > > struct intel_sa_info { > - u8 deburst, mpagesize, deprogbwlimit, displayrtids; > + u8 deburst, mpagesize, deprogbwlimit; > + u16 displayrtids; > }; > > static const struct intel_sa_info icl_sa_info = { > @@ -142,6 +143,14 @@ static const struct intel_sa_info icl_sa_info = { > .displayrtids = 128, > }; > > +static const struct intel_sa_info tgl_sa_info = { > + .deburst = 16, > + .mpagesize = 16, This should be 16 only for DDR4, and 32 otherwise - however, it's not actually used anywhere, so it doesn't matter, but a comment (in case it needs to be used in the future) would be good. > + .deprogbwlimit = 34, /* GB/s */ > + .displayrtids = 256, > +}; > + > + > static int icl_get_bw_info(struct drm_i915_private *dev_priv) > { > struct intel_qgv_info qi = {}; > @@ -208,6 +217,74 @@ static int icl_get_bw_info(struct drm_i915_private > *dev_priv) > return 0; > } > > +static int tgl_get_bw_info(struct drm_i915_private *dev_priv) > +{ > + struct intel_qgv_info qi = {}; > + const struct intel_sa_info *sa = &tgl_sa_info; > + bool is_y_tile = true; /* assume y tile may be used */ > + int num_channels; > + int deinterleave; > + int ipqdepth, ipqdepthpch; > + int dclk_max; > + int maxdebw; > + int c3_derating = 10; > + int c25_deprogbwpclimit = 60; > + int i, ret; > + > + ret = icl_get_qgv_points(dev_priv, &qi); > + if (ret) { > + DRM_DEBUG_KMS("Failed to get memory subsystem information, > ignoring bandwidth limits"); > + return ret; > + } > + num_channels = qi.num_channels; > + > + deinterleave = DIV_ROUND_UP(num_channels, is_y_tile ? 4 : 2); > + dclk_max = icl_sagv_max_dclk(&qi); > + > + ipqdepthpch = 16; > + > + maxdebw = min(sa->deprogbwlimit * 1000, > + icl_calc_bw(dclk_max, 16 * c25_deprogbwpclimit, 100)); /* > 60% */ > + ipqdepth = min(ipqdepthpch, sa->displayrtids / num_channels); > + > + for (i = 0; i < ARRAY_SIZE(dev_priv->max_bw); i++) { > + struct intel_bw_info *bi = &dev_priv->max_bw[i]; > + int clpchgroup; > + int j; > + > + clpchgroup = (sa->deburst * deinterleave / num_channels) << i; > + bi->num_planes = (ipqdepth - clpchgroup) / clpchgroup; > + > + bi->num_qgv_points = qi.num_points; > + > + for (j = 0; j < qi.num_points; j++) { > + const struct intel_qgv_point *sp = &qi.points[j]; > + int ct, bw; > + > + /* > + * Max row cycle time > + * > + * FIXME what is the logic behind the > + * assumed burst length? > + */ > + ct = max_t(int, sp->t_rc, sp->t_rp + sp->t_rcd + > + (clpchgroup - 1) * qi.t_bl + sp->t_rdpre); qi.t_bl also needs to be set dynamically based on memory type - for DDR4, 4, otherwise 16 -James > + bw = icl_calc_bw(sp->dclk, clpchgroup * 32 * > num_channels, ct); > + > + bi->deratedbw[j] = min(maxdebw, > + bw * (100 - c3_derating) / 100); > /* 90% */ > + > + DRM_DEBUG_KMS("BW%d / QGV %d: num_planes=%d > deratedbw=%u\n", > + i, j, bi->num_planes, bi->deratedbw[j]); > + } > + > + if (bi->num_planes == 1) > + break; > + } > + > + return 0; > +} > + > static unsigned int icl_max_bw(struct drm_i915_private *dev_priv, > int num_planes, int qgv_point) > { > @@ -231,10 +308,35 @@ static unsigned int icl_max_bw(struct drm_i915_private > *dev_priv, > return 0; > } > > +static unsigned int tgl_max_bw(struct drm_i915_private *dev_priv, > + int num_planes, int qgv_point) > +{ > + int i; > + > + for (i = 0; i < ARRAY_SIZE(dev_priv->max_bw); i++) { > + const struct intel_bw_info *bi = > + &dev_priv->max_bw[i]; > + > + /* > + * Pcode will not expose all QGV points when > + * SAGV is forced to off/min/med/max. > + */ > + if (qgv_point >= bi->num_qgv_points) > + return UINT_MAX; > + > + if (num_planes >= bi->num_planes) > + return bi->deratedbw[qgv_point]; > + } > + > + return 0; > +} > + > void intel_bw_init_hw(struct drm_i915_private *dev_priv) > { > if (IS_GEN(dev_priv, 11)) > icl_get_bw_info(dev_priv); > + else if (IS_GEN(dev_priv, 12)) > + tgl_get_bw_info(dev_priv); > } > > static unsigned int intel_max_data_rate(struct drm_i915_private *dev_priv, > @@ -249,6 +351,10 @@ static unsigned int intel_max_data_rate(struct > drm_i915_private *dev_priv, > return min3(icl_max_bw(dev_priv, num_planes, 0), > icl_max_bw(dev_priv, num_planes, 1), > icl_max_bw(dev_priv, num_planes, 2)); > + else if (IS_GEN(dev_priv, 12)) > + return min3(tgl_max_bw(dev_priv, num_planes, 0), > + tgl_max_bw(dev_priv, num_planes, 1), > + tgl_max_bw(dev_priv, num_planes, 2)); > else > return UINT_MAX; > } > -- > 2.17.1 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
