From patchwork Tue Sep 10 13:42:18 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?VmlsbGUgU3lyasOkbMOk?= X-Patchwork-Id: 13798551 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 D09D3ECE57A for ; Tue, 10 Sep 2024 13:42:34 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 622AD10E7F4; Tue, 10 Sep 2024 13:42:34 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="cSUd1Geb"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.13]) by gabe.freedesktop.org (Postfix) with ESMTPS id CF00210E7F4; Tue, 10 Sep 2024 13:42:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1725975754; x=1757511754; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=QWXekUZ6f972PjoHVcQeqHMb7+LOGTHyo63uvzdIs94=; b=cSUd1GebFYAGj6dNSzhxWb0Ggxkha9OyODJKelk2dbT0EuEfaIJKzPEW V6UjOTY8HjI6aZPHs/DiUKaAW+Gxixh9eiBa56N6MgFRaTPrYkOQKqaJ9 xlh1OufxMDEAiqlrcbweKW1tijAPQlT6lp5mthCs/NktrGAA8b2QMxAzm 6y0sC7Xts8OEdUT5pfkHGPlEtTACASm5xv2aUy+lcYVyzZ3NLzM4YK51T ti8rrMD2FGpjLtS7EgCCD/PNu1y8wof+XGqmoNjraRp2Xxd1PZc2FmFK9 4Tm4N4wcUS3uk3GTj+TdWoeNqaIi2SNak+qhQxgZfKNdQOP6Nn8MBi9Cp Q==; X-CSE-ConnectionGUID: VtcjI3MqQK22ZbYktLLjPQ== X-CSE-MsgGUID: 4dBU229jS2qBu/cv9Ctkyw== X-IronPort-AV: E=McAfee;i="6700,10204,11191"; a="35861250" X-IronPort-AV: E=Sophos;i="6.10,217,1719903600"; d="scan'208";a="35861250" Received: from fmviesa008.fm.intel.com ([10.60.135.148]) by orvoesa105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Sep 2024 06:42:34 -0700 X-CSE-ConnectionGUID: 2pGKHZhzT5CLPfcUz0umnw== X-CSE-MsgGUID: uBvYoAOBTzaWZ1v8NVhU4Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,217,1719903600"; d="scan'208";a="67081319" Received: from stinkpipe.fi.intel.com (HELO stinkbox) ([10.237.72.74]) by fmviesa008.fm.intel.com with SMTP; 10 Sep 2024 06:42:31 -0700 Received: by stinkbox (sSMTP sendmail emulation); Tue, 10 Sep 2024 16:42:30 +0300 From: Ville Syrjala To: intel-gfx@lists.freedesktop.org Cc: intel-xe@lists.freedesktop.org Subject: [PATCH 4/5] drm/i915/bios: Extract vbt_signature[] Date: Tue, 10 Sep 2024 16:42:18 +0300 Message-ID: <20240910134219.28479-5-ville.syrjala@linux.intel.com> X-Mailer: git-send-email 2.44.2 In-Reply-To: <20240910134219.28479-1-ville.syrjala@linux.intel.com> References: <20240910134219.28479-1-ville.syrjala@linux.intel.com> MIME-Version: 1.0 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" From: Ville Syrjälä Replace the three hand rolled "$VBT"s with a vbt_signature[] to avoid accidents. Signed-off-by: Ville Syrjälä Reviewed-by: Jani Nikula --- drivers/gpu/drm/i915/display/intel_bios.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c index cbbda94c3dab..0b92b494117f 100644 --- a/drivers/gpu/drm/i915/display/intel_bios.c +++ b/drivers/gpu/drm/i915/display/intel_bios.c @@ -2964,6 +2964,8 @@ static const struct bdb_header *get_bdb_header(const struct vbt_header *vbt) return _vbt + vbt->bdb_offset; } +static const char vbt_signature[4] = "$VBT"; + /** * intel_bios_is_valid_vbt - does the given buffer contain a valid VBT * @display: display device @@ -2986,7 +2988,7 @@ bool intel_bios_is_valid_vbt(struct intel_display *display, return false; } - if (memcmp(vbt->signature, "$VBT", 4)) { + if (memcmp(vbt->signature, vbt_signature, sizeof(vbt_signature))) { drm_dbg_kms(display->drm, "VBT invalid signature\n"); return false; } @@ -3082,9 +3084,11 @@ static struct vbt_header *spi_oprom_get_vbt(struct intel_display *display, oprom_offset = intel_uncore_read(&i915->uncore, OROM_OFFSET); oprom_offset &= OROM_OFFSET_MASK; + BUILD_BUG_ON(sizeof(vbt_signature) != sizeof(u32)); + for (count = 0; count < oprom_size; count += 4) { data = intel_spi_read32(&i915->uncore, oprom_offset + count); - if (data == *((const u32 *)"$VBT")) { + if (data == *((const u32 *)vbt_signature)) { found = oprom_offset + count; break; } @@ -3144,9 +3148,11 @@ static struct vbt_header *oprom_get_vbt(struct intel_display *display, if (!oprom) return NULL; + BUILD_BUG_ON(sizeof(vbt_signature) != sizeof(u32)); + /* Scour memory looking for the VBT signature. */ for (i = 0; i + 4 < size; i += 4) { - if (ioread32(oprom + i) != *((const u32 *)"$VBT")) + if (ioread32(oprom + i) != *((const u32 *)vbt_signature)) continue; p = oprom + i;