From patchwork Tue Oct 12 06:12:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Sripada, Radhakrishna" X-Patchwork-Id: 12551543 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5D1A8C433EF for ; Tue, 12 Oct 2021 06:12:31 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1BDA460041 for ; Tue, 12 Oct 2021 06:12:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 1BDA460041 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 94C1389DED; Tue, 12 Oct 2021 06:12:30 +0000 (UTC) Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by gabe.freedesktop.org (Postfix) with ESMTPS id 62EDA89DED for ; Tue, 12 Oct 2021 06:12:28 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10134"; a="227339020" X-IronPort-AV: E=Sophos;i="5.85,366,1624345200"; d="scan'208";a="227339020" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Oct 2021 23:12:15 -0700 X-IronPort-AV: E=Sophos;i="5.85,366,1624345200"; d="scan'208";a="591611163" Received: from invictus.jf.intel.com ([10.165.21.205]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Oct 2021 23:12:15 -0700 From: Radhakrishna Sripada To: intel-gfx@lists.freedesktop.org Date: Mon, 11 Oct 2021 23:12:05 -0700 Message-Id: <20211012061205.9012-1-radhakrishna.sripada@intel.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH v6] drm/i915: Update memory bandwidth formulae X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" The formulae has been updated to include more variables. Make sure the code carries the same. Bspec: 64631 v2: Make GEN11 follow the default route and fix calculation of maxdebw(RK) v3: Fix div by zero on default case Correct indent for fallthrough(Jani) v4: Fix div by zero on gen11. v5: Fix 0 max_numchannels case v6: - Split gen11/gen12 algorithms - Fix RKL deburst value - Fix difference b/ween ICL and TGL algorithms - Protect deinterleave from being 0 - Warn when numchannels exceeds max_numchannels - Fix scaling of clk_max from different units - s/deinterleave/channelwidth/ in calculating peakbw - Fix off by one for num_planes TGL+ - Fix SAGV check Cc: Ville Syrjälä Suggested-by: Matt Roper Signed-off-by: Radhakrishna Sripada --- drivers/gpu/drm/i915/display/intel_bw.c | 211 ++++++++++++++++++++---- 1 file changed, 179 insertions(+), 32 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c index 4b94256d7319..548850a8ebd1 100644 --- a/drivers/gpu/drm/i915/display/intel_bw.c +++ b/drivers/gpu/drm/i915/display/intel_bw.c @@ -27,6 +27,9 @@ struct intel_qgv_info { u8 num_points; u8 num_psf_points; u8 t_bl; + u8 max_numchannels; + u8 channel_width; + u8 deinterleave; }; static int dg1_mchbar_read_qgv_point_info(struct drm_i915_private *dev_priv, @@ -69,6 +72,7 @@ static int icl_pcode_read_qgv_point_info(struct drm_i915_private *dev_priv, int point) { u32 val = 0, val2 = 0; + u16 dclk; int ret; ret = sandybridge_pcode_read(dev_priv, @@ -78,7 +82,8 @@ static int icl_pcode_read_qgv_point_info(struct drm_i915_private *dev_priv, if (ret) return ret; - sp->dclk = val & 0xffff; + dclk = val & 0xffff; + sp->dclk = DIV_ROUND_UP((16667 * dclk) + (DISPLAY_VER(dev_priv) > 11 ? 500 : 0), 1000); sp->t_rp = (val & 0xff0000) >> 16; sp->t_rcd = (val & 0xff000000) >> 24; @@ -133,7 +138,8 @@ int icl_pcode_restrict_qgv_points(struct drm_i915_private *dev_priv, } static int icl_get_qgv_points(struct drm_i915_private *dev_priv, - struct intel_qgv_info *qi) + struct intel_qgv_info *qi, + bool is_y_tile) { const struct dram_info *dram_info = &dev_priv->dram_info; int i, ret; @@ -144,17 +150,41 @@ static int icl_get_qgv_points(struct drm_i915_private *dev_priv, if (DISPLAY_VER(dev_priv) == 12) switch (dram_info->type) { case INTEL_DRAM_DDR4: - qi->t_bl = 4; + qi->t_bl = is_y_tile ? 8 : 4; + qi->max_numchannels = 2; + qi->channel_width = 64; + qi->deinterleave = is_y_tile ? 1 : 2; break; case INTEL_DRAM_DDR5: - qi->t_bl = 8; + qi->t_bl = is_y_tile ? 16 : 8; + qi->max_numchannels = 4; + qi->channel_width = 32; + qi->deinterleave = is_y_tile ? 1 : 2; + break; + case INTEL_DRAM_LPDDR4: + if (IS_ROCKETLAKE(dev_priv)) { + qi->t_bl = 8; + qi->max_numchannels = 4; + qi->channel_width = 32; + qi->deinterleave = 2; + break; + } + fallthrough; + case INTEL_DRAM_LPDDR5: + qi->t_bl = 16; + qi->max_numchannels = 8; + qi->channel_width = 16; + qi->deinterleave = is_y_tile ? 2 : 4; break; default: qi->t_bl = 16; + qi->max_numchannels = 1; break; } - else if (DISPLAY_VER(dev_priv) == 11) + else if (DISPLAY_VER(dev_priv) == 11) { qi->t_bl = dev_priv->dram_info.type == INTEL_DRAM_DDR4 ? 4 : 8; + qi->max_numchannels = 1; + } if (drm_WARN_ON(&dev_priv->drm, qi->num_points > ARRAY_SIZE(qi->points))) @@ -193,12 +223,6 @@ static int icl_get_qgv_points(struct drm_i915_private *dev_priv, return 0; } -static int icl_calc_bw(int dclk, int num, int den) -{ - /* multiples of 16.666MHz (100/6) */ - return DIV_ROUND_CLOSEST(num * dclk * 100, den * 6); -} - static int adl_calc_psf_bw(int clk) { /* @@ -240,7 +264,7 @@ static const struct intel_sa_info tgl_sa_info = { }; static const struct intel_sa_info rkl_sa_info = { - .deburst = 16, + .deburst = 8, .deprogbwlimit = 20, /* GB/s */ .displayrtids = 128, .derating = 10, @@ -263,36 +287,32 @@ static const struct intel_sa_info adlp_sa_info = { static int icl_get_bw_info(struct drm_i915_private *dev_priv, const struct intel_sa_info *sa) { struct intel_qgv_info qi = {}; - bool is_y_tile = true; /* assume y tile may be used */ int num_channels = max_t(u8, 1, dev_priv->dram_info.num_channels); - int deinterleave; - int ipqdepth, ipqdepthpch; + int ipqdepth, ipqdepthpch = 16; int dclk_max; int maxdebw; + int num_groups = ARRAY_SIZE(dev_priv->max_bw); int i, ret; - ret = icl_get_qgv_points(dev_priv, &qi); + ret = icl_get_qgv_points(dev_priv, &qi, true); if (ret) { drm_dbg_kms(&dev_priv->drm, "Failed to get memory subsystem information, ignoring bandwidth limits"); return ret; } - 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, dclk_max * 16 * 6 / 10); - maxdebw = min(sa->deprogbwlimit * 1000, - icl_calc_bw(dclk_max, 16, 1) * 6 / 10); /* 60% */ ipqdepth = min(ipqdepthpch, sa->displayrtids / num_channels); - for (i = 0; i < ARRAY_SIZE(dev_priv->max_bw); i++) { + for (i = 0; i < num_groups; i++) { struct intel_bw_info *bi = &dev_priv->max_bw[i]; int clpchgroup; int j; - clpchgroup = (sa->deburst * deinterleave / num_channels) << i; + clpchgroup = (sa->deburst * qi.deinterleave / num_channels) << i; bi->num_planes = (ipqdepth - clpchgroup) / clpchgroup + 1; bi->num_qgv_points = qi.num_points; @@ -310,7 +330,106 @@ static int icl_get_bw_info(struct drm_i915_private *dev_priv, const struct intel */ ct = max_t(int, sp->t_rc, sp->t_rp + sp->t_rcd + (clpchgroup - 1) * qi.t_bl + sp->t_rdpre); - bw = icl_calc_bw(sp->dclk, clpchgroup * 32 * num_channels, ct); + bw = DIV_ROUND_UP(sp->dclk * clpchgroup * 32 * num_channels, ct); + + bi->deratedbw[j] = min(maxdebw, + bw * (100 - sa->derating) / 100); + + drm_dbg_kms(&dev_priv->drm, + "BW%d / QGV %d: num_planes=%d deratedbw=%u\n", + i, j, bi->num_planes, bi->deratedbw[j]); + } + } + /* + * In case if SAGV is disabled in BIOS, we always get 1 + * SAGV point, but we can't send PCode commands to restrict it + * as it will fail and pointless anyway. + */ + if (qi.num_points == 1) + dev_priv->sagv_status = I915_SAGV_NOT_CONTROLLED; + else + dev_priv->sagv_status = I915_SAGV_ENABLED; + + return 0; +} + +static int tgl_get_bw_info(struct drm_i915_private *dev_priv, const struct intel_sa_info *sa) +{ + struct intel_qgv_info qi = {}; + const struct dram_info *dram_info = &dev_priv->dram_info; + bool is_y_tile = true; /* assume y tile may be used */ + int num_channels = max_t(u8, 1, dev_priv->dram_info.num_channels); + int ipqdepth, ipqdepthpch = 16; + int dclk_max; + int maxdebw, peakbw; + int clperchgroup; + int num_groups = ARRAY_SIZE(dev_priv->max_bw); + int i, ret; + + ret = icl_get_qgv_points(dev_priv, &qi, is_y_tile); + if (ret) { + drm_dbg_kms(&dev_priv->drm, + "Failed to get memory subsystem information, ignoring bandwidth limits"); + return ret; + } + + if (dram_info->type == INTEL_DRAM_LPDDR4 || dram_info->type == INTEL_DRAM_LPDDR5) + num_channels *= 2; + + qi.deinterleave = qi.deinterleave ? : DIV_ROUND_UP(num_channels, is_y_tile ? 4 : 2); + + if (num_channels < qi.max_numchannels && DISPLAY_VER(dev_priv) >= 12) + qi.deinterleave = max(DIV_ROUND_UP(qi.deinterleave, 2), 1); + + if (DISPLAY_VER(dev_priv) > 11 && num_channels > qi.max_numchannels) + drm_warn(&dev_priv->drm, "Number of channels exceeds max number of channels."); + if (qi.max_numchannels != 0) + num_channels = min_t(u8, num_channels, qi.max_numchannels); + + dclk_max = icl_sagv_max_dclk(&qi); + + peakbw = num_channels * DIV_ROUND_UP(qi.channel_width, 8) * dclk_max; + maxdebw = min(sa->deprogbwlimit * 1000, peakbw * 6 / 10); /* 60% */ + + ipqdepth = min(ipqdepthpch, sa->displayrtids / num_channels); + /* + * clperchgroup = 4kpagespermempage * clperchperblock, + * clperchperblock = 8 / num_channels * interleave + */ + clperchgroup = 4 * DIV_ROUND_UP(8, num_channels) * qi.deinterleave; + + for (i = 0; i < num_groups; i++) { + struct intel_bw_info *bi = &dev_priv->max_bw[i]; + struct intel_bw_info *bi_next; + int clpchgroup; + int j; + + if (i < num_groups - 1) + bi_next = &dev_priv->max_bw[i + 1]; + + clpchgroup = (sa->deburst * qi.deinterleave / num_channels) << i; + + if (i < num_groups - 1 && clpchgroup < clperchgroup) + bi_next->num_planes = (ipqdepth - clpchgroup) / clpchgroup + 1; + else + bi_next->num_planes = 0; + + bi->num_qgv_points = qi.num_points; + bi->num_psf_gv_points = qi.num_psf_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); + bw = DIV_ROUND_UP(sp->dclk * clpchgroup * 32 * num_channels, ct); bi->deratedbw[j] = min(maxdebw, bw * (100 - sa->derating) / 100); @@ -329,9 +448,6 @@ static int icl_get_bw_info(struct drm_i915_private *dev_priv, const struct intel "BW%d / PSF GV %d: num_planes=%d bw=%u\n", i, j, bi->num_planes, bi->psf_bw[j]); } - - if (bi->num_planes == 1) - break; } /* @@ -388,13 +504,41 @@ static unsigned int icl_max_bw(struct drm_i915_private *dev_priv, if (qgv_point >= bi->num_qgv_points) return UINT_MAX; - if (num_planes >= bi->num_planes) + if (num_planes > bi->num_planes) return bi->deratedbw[qgv_point]; } return 0; } +static unsigned int tgl_max_bw(struct drm_i915_private *dev_priv, + int num_planes, int qgv_point) +{ + int i; + + /* + * Let's return max bw for 0 planes + */ + num_planes = max(1, num_planes); + + for (i = ARRAY_SIZE(dev_priv->max_bw) - 1; i >= 0; 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 dev_priv->max_bw[0].deratedbw[qgv_point]; +} + static unsigned int adl_psf_bw(struct drm_i915_private *dev_priv, int psf_gv_point) { @@ -412,13 +556,13 @@ void intel_bw_init_hw(struct drm_i915_private *dev_priv) if (IS_DG2(dev_priv)) dg2_get_bw_info(dev_priv); else if (IS_ALDERLAKE_P(dev_priv)) - icl_get_bw_info(dev_priv, &adlp_sa_info); + tgl_get_bw_info(dev_priv, &adlp_sa_info); else if (IS_ALDERLAKE_S(dev_priv)) - icl_get_bw_info(dev_priv, &adls_sa_info); + tgl_get_bw_info(dev_priv, &adls_sa_info); else if (IS_ROCKETLAKE(dev_priv)) - icl_get_bw_info(dev_priv, &rkl_sa_info); + tgl_get_bw_info(dev_priv, &rkl_sa_info); else if (DISPLAY_VER(dev_priv) == 12) - icl_get_bw_info(dev_priv, &tgl_sa_info); + tgl_get_bw_info(dev_priv, &tgl_sa_info); else if (DISPLAY_VER(dev_priv) == 11) icl_get_bw_info(dev_priv, &icl_sa_info); } @@ -746,7 +890,10 @@ int intel_bw_atomic_check(struct intel_atomic_state *state) for (i = 0; i < num_qgv_points; i++) { unsigned int max_data_rate; - max_data_rate = icl_max_bw(dev_priv, num_active_planes, i); + if (DISPLAY_VER(dev_priv) > 11) + max_data_rate = tgl_max_bw(dev_priv, num_active_planes, i); + else + max_data_rate = icl_max_bw(dev_priv, num_active_planes, i); /* * We need to know which qgv point gives us * maximum bandwidth in order to disable SAGV