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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F243EC61DA3 for ; Fri, 3 Mar 2023 23:13:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232128AbjCCXN2 (ORCPT ); Fri, 3 Mar 2023 18:13:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47646 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231834AbjCCXN1 (ORCPT ); Fri, 3 Mar 2023 18:13:27 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C201457F9; Fri, 3 Mar 2023 15:13:26 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 06E40CE229C; Fri, 3 Mar 2023 21:46:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 230B3C433A0; Fri, 3 Mar 2023 21:46:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1677879971; bh=KNB/gvnf8eLD2actKsJ+PYpfMYMabWWqOluMYv7CS4A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Y+ahD3qYj8nmFuGxZv72MVrDxHvOVNMETqVlCaQhCzYiGws0Zn4FZ37PYm3dRrain 8THT6w7+a4+jJXu5YR5A85bL/YCyCrpQHZrcw2OxMoIap3sQeGKPy5Ez7E7mNOxq2E a5hhEFu/UoLllwfiQj8xQUgFhJTKausRW5653Zb6jNRPDAlVhvxJXp0KHnINzh8LKy NCHzuzhcm9z6rdJggTSVZ0YEayRmDfWb8hlQvo7dP6sn/lRiqafb7t5COAU7WACuZg CsgWksPsDSf160CiJZMEkS6FApufbgHCOJ4tkfj6wa63C0pXM0gOsaW4FC3M3AXpZq jisfWxdbJNLFQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Alper Nebi Yasak , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH AUTOSEL 5.15 18/50] firmware: coreboot: framebuffer: Ignore reserved pixel color bits Date: Fri, 3 Mar 2023 16:44:59 -0500 Message-Id: <20230303214531.1450154-18-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230303214531.1450154-1-sashal@kernel.org> References: <20230303214531.1450154-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Alper Nebi Yasak [ Upstream commit e6acaf25cba14661211bb72181c35dd13b24f5b3 ] The coreboot framebuffer doesn't support transparency, its 'reserved' bit field is merely padding for byte/word alignment of pixel colors [1]. When trying to match the framebuffer to a simplefb format, the kernel driver unnecessarily requires the format's transparency bit field to exactly match this padding, even if the former is zero-width. Due to a coreboot bug [2] (fixed upstream), some boards misreport the reserved field's size as equal to its position (0x18 for both on a 'Lick' Chromebook), and the driver fails to probe where it would have otherwise worked fine with e.g. the a8r8g8b8 or x8r8g8b8 formats. Remove the transparency comparison with reserved bits. When the bits-per-pixel and other color components match, transparency will already be in a subset of the reserved field. Not forcing it to match reserved bits allows the driver to work on the boards which misreport the reserved field. It also enables using simplefb formats that don't have transparency bits, although this doesn't currently happen due to format support and ordering in linux/platform_data/simplefb.h. [1] https://review.coreboot.org/plugins/gitiles/coreboot/+/4.19/src/commonlib/include/commonlib/coreboot_tables.h#255 [2] https://review.coreboot.org/plugins/gitiles/coreboot/+/4.13/src/drivers/intel/fsp2_0/graphics.c#82 Signed-off-by: Alper Nebi Yasak Link: https://lore.kernel.org/r/20230122190433.195941-1-alpernebiyasak@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/firmware/google/framebuffer-coreboot.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/firmware/google/framebuffer-coreboot.c b/drivers/firmware/google/framebuffer-coreboot.c index c6dcc1ef93acf..c323a818805cc 100644 --- a/drivers/firmware/google/framebuffer-coreboot.c +++ b/drivers/firmware/google/framebuffer-coreboot.c @@ -43,9 +43,7 @@ static int framebuffer_probe(struct coreboot_device *dev) fb->green_mask_pos == formats[i].green.offset && fb->green_mask_size == formats[i].green.length && fb->blue_mask_pos == formats[i].blue.offset && - fb->blue_mask_size == formats[i].blue.length && - fb->reserved_mask_pos == formats[i].transp.offset && - fb->reserved_mask_size == formats[i].transp.length) + fb->blue_mask_size == formats[i].blue.length) pdata.format = formats[i].name; } if (!pdata.format) -- 2.39.2