From mboxrd@z Thu Jan 1 00:00:00 1970 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 84066C433EF for ; Thu, 27 Jan 2022 08:21:03 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BC67F10E54F; Thu, 27 Jan 2022 08:21:02 +0000 (UTC) Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id 250E810E49B for ; Thu, 27 Jan 2022 08:21:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1643271661; x=1674807661; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=D7iSzv2WCrXiD2GO4BnohfHNGEsENno2xLeXRGANnWI=; b=mmenmMiT+sDyVwZcKoVWvFIWoDhxoxUTMTe3v6bfDL1XB/qYc+hAuFun xeD/XOzR/PzAt5koHJqOWpjoh3/jGaT7zuqn6s5sN7SfL04GTbwZw+a+I vcWKoBTBfYoklHWfmiRv3NYB7tvh8kgT/7N0wzomWLdxsfmrSQzcINzy2 t7XFEOUKkEhUYnHiwgAHRaFMbVg3xPvzrsGR0a/s4G2CWAqjuLLUMewDv YYBhj0sk7h2yokIxngeHxCXlJyhmwKutVtrjhkixKzfSZJ86gewnEFXQb P8koqjVuVyxcpclhYWMBC62502+IZKIAazfLxqrYuBkvYEY6TxY85jT+Y g==; X-IronPort-AV: E=McAfee;i="6200,9189,10239"; a="333139833" X-IronPort-AV: E=Sophos;i="5.88,320,1635231600"; d="scan'208";a="333139833" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Jan 2022 00:21:00 -0800 X-IronPort-AV: E=Sophos;i="5.88,320,1635231600"; d="scan'208";a="477779199" Received: from unknown (HELO intel.com) ([10.237.72.65]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Jan 2022 00:20:58 -0800 Date: Thu, 27 Jan 2022 10:21:06 +0200 From: "Lisovskiy, Stanislav" To: Ville Syrjala Message-ID: <20220127082106.GC31846@intel.com> References: <20220118092354.11631-1-ville.syrjala@linux.intel.com> <20220118092354.11631-4-ville.syrjala@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20220118092354.11631-4-ville.syrjala@linux.intel.com> User-Agent: Mutt/1.9.4 (2018-02-28) Subject: Re: [Intel-gfx] [PATCH 03/15] drm/i915: Fix plane relative_data_rate calculation 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: , Cc: intel-gfx@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Tue, Jan 18, 2022 at 11:23:42AM +0200, Ville Syrjala wrote: > From: Ville Syrjälä > > We are currently computing the relative data rates as > src_size * scale_factor where scale_factor is src_size / dst_size. > Thus relative data rate is src_size * src_size / dst_size, > which is just utter nonsense. What we really seem to want is > just a reasonable estimate on how much data will be fetched > which is just src_size. So let's do that instead. > > Signed-off-by: Ville Syrjälä Omg, how could it stay like this all the time? I actually had similar question, but thought that there just might be again some magical/empirical heuristics behind this. Need to challenge more anything, which can't be explained with BSpec formulas or by common sense... Reviewed-by: Stanislav Lisovskiy > --- > drivers/gpu/drm/i915/intel_pm.c | 63 ++------------------------------- > 1 file changed, 2 insertions(+), 61 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c > index 9a9d4acb2988..e8fb56f288b4 100644 > --- a/drivers/gpu/drm/i915/intel_pm.c > +++ b/drivers/gpu/drm/i915/intel_pm.c > @@ -4373,55 +4373,6 @@ void skl_pipe_ddb_get_hw_state(struct intel_crtc *crtc, > intel_display_power_put(dev_priv, power_domain, wakeref); > } > > -/* > - * Determines the downscale amount of a plane for the purposes of watermark calculations. > - * The bspec defines downscale amount as: > - * > - * """ > - * Horizontal down scale amount = maximum[1, Horizontal source size / > - * Horizontal destination size] > - * Vertical down scale amount = maximum[1, Vertical source size / > - * Vertical destination size] > - * Total down scale amount = Horizontal down scale amount * > - * Vertical down scale amount > - * """ > - * > - * Return value is provided in 16.16 fixed point form to retain fractional part. > - * Caller should take care of dividing & rounding off the value. > - */ > -static uint_fixed_16_16_t > -skl_plane_downscale_amount(const struct intel_crtc_state *crtc_state, > - const struct intel_plane_state *plane_state) > -{ > - struct drm_i915_private *dev_priv = to_i915(crtc_state->uapi.crtc->dev); > - u32 src_w, src_h, dst_w, dst_h; > - uint_fixed_16_16_t fp_w_ratio, fp_h_ratio; > - uint_fixed_16_16_t downscale_h, downscale_w; > - > - if (drm_WARN_ON(&dev_priv->drm, > - !intel_wm_plane_visible(crtc_state, plane_state))) > - return u32_to_fixed16(0); > - > - /* > - * Src coordinates are already rotated by 270 degrees for > - * the 90/270 degree plane rotation cases (to match the > - * GTT mapping), hence no need to account for rotation here. > - * > - * n.b., src is 16.16 fixed point, dst is whole integer. > - */ > - src_w = drm_rect_width(&plane_state->uapi.src) >> 16; > - src_h = drm_rect_height(&plane_state->uapi.src) >> 16; > - dst_w = drm_rect_width(&plane_state->uapi.dst); > - dst_h = drm_rect_height(&plane_state->uapi.dst); > - > - fp_w_ratio = div_fixed16(src_w, dst_w); > - fp_h_ratio = div_fixed16(src_h, dst_h); > - downscale_w = max_fixed16(fp_w_ratio, u32_to_fixed16(1)); > - downscale_h = max_fixed16(fp_h_ratio, u32_to_fixed16(1)); > - > - return mul_fixed16(downscale_w, downscale_h); > -} > - > struct dbuf_slice_conf_entry { > u8 active_pipes; > u8 dbuf_mask[I915_MAX_PIPES]; > @@ -4932,10 +4883,7 @@ skl_plane_relative_data_rate(const struct intel_crtc_state *crtc_state, > { > struct intel_plane *plane = to_intel_plane(plane_state->uapi.plane); > const struct drm_framebuffer *fb = plane_state->hw.fb; > - u32 data_rate; > - u32 width = 0, height = 0; > - uint_fixed_16_16_t down_scale_amount; > - u64 rate; > + int width, height; > > if (!plane_state->uapi.visible) > return 0; > @@ -4961,14 +4909,7 @@ skl_plane_relative_data_rate(const struct intel_crtc_state *crtc_state, > height /= 2; > } > > - data_rate = width * height; > - > - down_scale_amount = skl_plane_downscale_amount(crtc_state, plane_state); > - > - rate = mul_round_up_u32_fixed16(data_rate, down_scale_amount); > - > - rate *= fb->format->cpp[color_plane]; > - return rate; > + return width * height * fb->format->cpp[color_plane]; > } > > static u64 > -- > 2.32.0 >