From patchwork Wed Oct 26 18:28:21 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marijn Suijten X-Patchwork-Id: 618870 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3ED22FA3744 for ; Wed, 26 Oct 2022 18:29:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234440AbiJZS3C (ORCPT ); Wed, 26 Oct 2022 14:29:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56488 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234230AbiJZS2s (ORCPT ); Wed, 26 Oct 2022 14:28:48 -0400 Received: from relay06.th.seeweb.it (relay06.th.seeweb.it [5.144.164.167]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A9ED4DB54F for ; Wed, 26 Oct 2022 11:28:47 -0700 (PDT) Received: from localhost.localdomain (94-209-172-39.cable.dynamic.v4.ziggo.nl [94.209.172.39]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by m-r2.th.seeweb.it (Postfix) with ESMTPSA id 7E8D03F73D; Wed, 26 Oct 2022 20:28:45 +0200 (CEST) From: Marijn Suijten To: phone-devel@vger.kernel.org, Rob Clark , Abhinav Kumar , Dmitry Baryshkov , Vinod Koul Cc: ~postmarketos/upstreaming@lists.sr.ht, AngeloGioacchino Del Regno , Konrad Dybcio , Martin Botka , Jami Kettunen , Marijn Suijten , Sean Paul , David Airlie , Daniel Vetter , Douglas Anderson , Vladimir Lypak , linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, linux-kernel@vger.kernel.org, Marek Vasut Subject: [PATCH v4 07/10] drm/msm/dsi: Account for DSC's bits_per_pixel having 4 fractional bits Date: Wed, 26 Oct 2022 20:28:21 +0200 Message-Id: <20221026182824.876933-8-marijn.suijten@somainline.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221026182824.876933-1-marijn.suijten@somainline.org> References: <20221026182824.876933-1-marijn.suijten@somainline.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org drm_dsc_config's bits_per_pixel field holds a fractional value with 4 bits, which all panel drivers should adhere to for drm_dsc_pps_payload_pack() to generate a valid payload. All code in the DSI driver here seems to assume that this field doesn't contain any fractional bits, hence resulting in the wrong values being computed. Since none of the calculations leave any room for fractional bits or seem to indicate any possible area of support, disallow such values altogether. calculate_rc_params() in intel_vdsc.c performs an identical bitshift to get at this integer value. Fixes: b9080324d6ca ("drm/msm/dsi: add support for dsc data") Reviewed-by: Abhinav Kumar Reviewed-by: Dmitry Baryshkov Signed-off-by: Marijn Suijten --- drivers/gpu/drm/msm/dsi/dsi_host.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c index 0d130bded38d..8da27c740c1c 100644 --- a/drivers/gpu/drm/msm/dsi/dsi_host.c +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c @@ -34,7 +34,7 @@ #define DSI_RESET_TOGGLE_DELAY_MS 20 -static int dsi_populate_dsc_params(struct drm_dsc_config *dsc); +static int dsi_populate_dsc_params(struct msm_dsi_host *msm_host, struct drm_dsc_config *dsc); static int dsi_get_version(const void __iomem *base, u32 *major, u32 *minor) { @@ -909,6 +909,7 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi) u32 va_end = va_start + mode->vdisplay; u32 hdisplay = mode->hdisplay; u32 wc; + int ret; DBG(""); @@ -944,7 +945,9 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi) /* we do the calculations for dsc parameters here so that * panel can use these parameters */ - dsi_populate_dsc_params(dsc); + ret = dsi_populate_dsc_params(msm_host, dsc); + if (ret) + return; /* Divide the display by 3 but keep back/font porch and * pulse width same @@ -1770,9 +1773,15 @@ static char bpg_offset[DSC_NUM_BUF_RANGES] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12 }; -static int dsi_populate_dsc_params(struct drm_dsc_config *dsc) +static int dsi_populate_dsc_params(struct msm_dsi_host *msm_host, struct drm_dsc_config *dsc) { int i; + u16 bpp = dsc->bits_per_pixel >> 4; + + if (dsc->bits_per_pixel & 0xf) { + DRM_DEV_ERROR(&msm_host->pdev->dev, "DSI does not support fractional bits_per_pixel\n"); + return -EINVAL; + } dsc->rc_model_size = 8192; dsc->first_line_bpg_offset = 12; @@ -1793,8 +1802,8 @@ static int dsi_populate_dsc_params(struct drm_dsc_config *dsc) dsc->rc_range_params[i].range_bpg_offset = bpg_offset[i]; } - dsc->initial_offset = 6144; /* Not bpp 12 */ - if (dsc->bits_per_pixel != 8) + dsc->initial_offset = 6144; /* Not bpp 12 */ + if (bpp != 8) dsc->initial_offset = 2048; /* bpp = 12 */ if (dsc->bits_per_component <= 10)