From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f42.google.com (mail-wr1-f42.google.com [209.85.221.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 23E16345EA3 for ; Fri, 31 Jul 2026 21:50:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.42 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785534652; cv=none; b=jqJvuUHS67y6RRnIJjrsPaFBBLVIQaJ/sziCGOUBovAP0uH1FZSHE5LoCvU+we+ScdZTmKbh4Da9qLmHpnfPG/0n7JcI1ANRs+Yvzwwr7PJ9FR7ws0IKl0SX49NUszv8nsCTypfdTmzc8yy9envrbEx/Kvv1lv6W8ItJ+DL0cCc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785534652; c=relaxed/simple; bh=1t1Xcl0vx0rLkiOp8M9P11f9v6z8fBleVFwCSvlK7k0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=C9zpfu3XTWMxUWBSsVqW/rExNE7nKyraVZDPIVIXDjMT4gkILU3RAC/fVxdsVuWV2LcUJiR0yrYqeYGTwNZ/vmb7FVXu/MVYTKRrbXHFsNVjphroXcbCcsNnltlHcACEA5tjWP30ON0KX891NDtXGchtnoU8+FCsTOnum0RJ6yU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=p5H/4bsg; arc=none smtp.client-ip=209.85.221.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="p5H/4bsg" Received: by mail-wr1-f42.google.com with SMTP id ffacd0b85a97d-47df43bfb07so753354f8f.1 for ; Fri, 31 Jul 2026 14:50:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1785534648; x=1786139448; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=xecpazbmAHToNRI7HHvo3rBeU785pIEnzPP95T0hHMQ=; b=p5H/4bsg+Y5P7YGEF3/HYA1SYqhUxHmtGkKcjCKKAzZY90Z8Eot4ZVFphXqYwsgJ/l SPvMd+vpjK/zXNThrNdb0MWGsZ6XjQbqbKtspZ1/kCACdFyjFtXFTdUl+9CC1zAjAJC/ 5PZIvS3IVo5ugQsWUs+MB1AaR28MfIOuhrq3kgA7GIx60zBDrXL2P+c4MWPXZKLXjo+Z JcpICBk1W7EiQwEMsUT/zc4O8PDCgzwQCPGsZp9IcIPTgPvZgwlOoS6bmwMfMiurU3Ly YgWWLhIQY0jTuubVk1U99csM/n3bMnyidPfET4K+400p4DegmejAgX08ERsejoKvyCJX Nrqg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785534648; x=1786139448; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=xecpazbmAHToNRI7HHvo3rBeU785pIEnzPP95T0hHMQ=; b=ohI0iXJ4a330c4hTU5C63I/THl+2h5yMoTVrgG6PJsvbt53mT+AR3PqQWEgXE9/1nB MtUKNClq/qZOl0CGMHCYxLRlR7G1kn/f1HVBO0g/lcYNhZWT5lJBfX+wgG1oVT8QsQKb 7VwG/r9L/TY/0BS73yW93f8FID68S/xzzyEdOJ4vkQEcPtbL/uTg3/euwfidv6XywDFm W8nmezFWZiP6iXOE3kT1GGxNOkXG/T6NgQ+RbgyMrfJ9F2AzdBMC1GRE8IfvQ2CS5sqo BCssCh/9i0BQCGlSZra2BcAlA4HKisxR35DecYGAclGlGnDE1eSEnmpTBOA+In2ivXiB EENw== X-Forwarded-Encrypted: i=1; AHgh+RpLK56/uDaKZ0so/Q7iGCLcC2H2/+8QT7t5I9de1kd++3LtKnIsJS2288Gr3U5ZvSWwX5utyJHiLzMS@vger.kernel.org X-Gm-Message-State: AOJu0Yyz33JMmsz0NVbd3Bk1wh+ULgpcTTeTWQfY1gUr2auqYLTPtBes 2bY1bbRRJEuioa2jpkVkTCacAqiFIei68uLX6F8UBALiU/i5L0YsEnGV X-Gm-Gg: AR+sD105FQKivOldVJYJ70MaWDx7Q1EU1++03s5txAvKKBZ/RuiJfRPaNhu3nSl7HWZ xx3hUY9KVBcR8AoSDbS1Nw61j7cHvDDfBQeoGJpcTJ801fbRj3ypAtrq2cc5j+6xcdiSIDtXU/r I0jk6N2LtI22QvTNjtqhuOkOc1Yp5HngnbfZrHVHCvIro2emk8r/L/i52b7VFrwvAlR+ePHTUt+ ygoHh82pJp2dg2c5OFcpHUbzbSSkt2kdR7Fhnp2e0TpMq3Ut7vuboOnYKtmJhKbx9KqtHejfTZ3 AWbumETZid6+Bw9ZZB0Nl1z+qQ11rZ4rdH/OAmqovdrhHXh8q+l0XHlqGlpZhP3M/IQuPw/+YCb L+ju72J734FPq5lJ3rRum0YhoT3WtHGloErLJ80LDN7VnwGDiVbZanljMs+cAoNMlaQkDYW0UyE gfk898hAi0mV4beMNH7LingaOz+lUBanaicEAmacvekVxHTM4gZC6mZZDNeUFK+YngRH2HtWWZ0 HmXlBeqh9Qetx7VgbK+0qRn X-Received: by 2002:a5d:64ed:0:b0:47f:77dc:b072 with SMTP id ffacd0b85a97d-47fd72c65f5mr2415622f8f.18.1785534648239; Fri, 31 Jul 2026 14:50:48 -0700 (PDT) Received: from ingenieria31.oficinasStQ.local ([79.116.62.64]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-47fd41e2484sm10186342f8f.11.2026.07.31.14.50.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 31 Jul 2026 14:50:47 -0700 (PDT) From: Max Pedraza To: Helge Deller Cc: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Thomas Zimmermann , Maxime Ripard , linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Max Pedraza Subject: [RFC PATCH 2/6] video: logo: allow the boot logo to come from the device tree Date: Fri, 31 Jul 2026 23:50:39 +0200 Message-Id: <20260731215043.30392-3-maximpedraza@gmail.com> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20260731215043.30392-1-maximpedraza@gmail.com> References: <20260731215043.30392-1-maximpedraza@gmail.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit With CONFIG_LOGO_DT_CLUT224 enabled, look for a node compatible with "linux,boot-logo-clut224" and, when one is present and enabled, use the image it carries in preference to the logos built into the kernel image. This lets a single kernel image serve several products, or several revisions of one product, that differ only in branding, at the cost of a larger device tree blob. The image is validated while it is parsed: the palette must be at most 224 entries, the pixel data length must match the declared geometry, and every pixel must reference an existing palette entry. A malformed node is reported and ignored, falling back to the built-in logo. The two allocations live for as long as the built-in logos do; they are released from fb_logo_late_init(), next to where the __initdata logos are marked as freed. If the node is absent or disabled, behaviour is unchanged. Signed-off-by: Max Pedraza --- drivers/video/logo/Kconfig | 13 +++ drivers/video/logo/logo.c | 157 +++++++++++++++++++++++++++++++++++++ 2 files changed, 170 insertions(+) diff --git a/drivers/video/logo/Kconfig b/drivers/video/logo/Kconfig index ce6bb7535..4af349b20 100644 --- a/drivers/video/logo/Kconfig +++ b/drivers/video/logo/Kconfig @@ -70,4 +70,17 @@ config LOGO_SUPERH_CLUT224 depends on SUPERH default y +config LOGO_DT_CLUT224 + bool "224-color logo supplied by the device tree" + depends on OF + help + Look for a boot logo in the device tree, in a node compatible with + "linux,boot-logo-clut224", instead of using one of the logos built + into the kernel image. This allows a single kernel image to be used + by several products that only differ in branding, at the cost of + making the device tree blob larger. + + If no such node is present, or it is disabled, the built-in logo + selected above is used, so saying Y here is safe. If unsure, say N. + endif # LOGO diff --git a/drivers/video/logo/logo.c b/drivers/video/logo/logo.c index 141f15a9a..b4f533df0 100644 --- a/drivers/video/logo/logo.c +++ b/drivers/video/logo/logo.c @@ -11,6 +11,9 @@ */ #include +#include +#include +#include #include #include @@ -22,6 +25,155 @@ static bool nologo; module_param(nologo, bool, 0); MODULE_PARM_DESC(nologo, "Disables startup logo"); +#ifdef CONFIG_LOGO_DT_CLUT224 + +#define LOGO_DT_COMPATIBLE "linux,boot-logo-clut224" +#define LOGO_DT_MAX_CLUT 224 +/* + * The first 32 palette entries are reserved for the console, so the logo + * colours start at index 32. That is an implementation detail of the frame + * buffer layer rather than a property of the image, so the device tree stores + * plain indices and the offset is applied here. + */ +#define LOGO_DT_CLUT_OFFSET 32 +/* Sanity limit on the image size, a device tree is not a good place for more */ +#define LOGO_DT_MAX_PIXELS SZ_32M + +static struct linux_logo logo_dt_clut224 = { + .type = LINUX_LOGO_CLUT224, +}; + +static unsigned char *logo_dt_clut; +static unsigned char *logo_dt_data; + +static int logo_dt_parse(struct device_node *np) +{ + unsigned int clutsize, npixels, i; + unsigned char *clut, *data; + u32 width, height; + int len, ret; + + ret = of_property_read_u32(np, "width", &width); + if (ret) + return ret; + + ret = of_property_read_u32(np, "height", &height); + if (ret) + return ret; + + if (!width || !height || (u64)width * height > LOGO_DT_MAX_PIXELS) + return -EINVAL; + + npixels = width * height; + + len = of_property_count_u8_elems(np, "clut"); + if (len < 3 || len % 3) + return -EINVAL; + + clutsize = len / 3; + if (clutsize > LOGO_DT_MAX_CLUT) + return -EINVAL; + + ret = of_property_count_u8_elems(np, "data"); + if (ret < 0) + return ret; + if ((unsigned int)ret != npixels) + return -EINVAL; + + clut = kmalloc(len, GFP_KERNEL); + if (!clut) + return -ENOMEM; + + data = kmalloc(npixels, GFP_KERNEL); + if (!data) { + ret = -ENOMEM; + goto err_free_clut; + } + + ret = of_property_read_u8_array(np, "clut", clut, len); + if (ret) + goto err_free_data; + + ret = of_property_read_u8_array(np, "data", data, npixels); + if (ret) + goto err_free_data; + + for (i = 0; i < npixels; i++) { + if (data[i] >= clutsize) { + ret = -ERANGE; + goto err_free_data; + } + data[i] += LOGO_DT_CLUT_OFFSET; + } + + logo_dt_clut = clut; + logo_dt_data = data; + + logo_dt_clut224.width = width; + logo_dt_clut224.height = height; + logo_dt_clut224.clutsize = clutsize; + logo_dt_clut224.clut = clut; + logo_dt_clut224.data = data; + + return 0; + +err_free_data: + kfree(data); +err_free_clut: + kfree(clut); + return ret; +} + +static const struct linux_logo *logo_dt_find(void) +{ + static bool probed; + struct device_node *np; + int ret; + + if (probed) + return logo_dt_data ? &logo_dt_clut224 : NULL; + + probed = true; + + np = of_find_compatible_node(NULL, NULL, LOGO_DT_COMPATIBLE); + if (!np) + return NULL; + + if (of_device_is_available(np)) { + ret = logo_dt_parse(np); + if (ret) + pr_warn("logo: ignoring malformed %pOF node (%d)\n", + np, ret); + } + + of_node_put(np); + + return logo_dt_data ? &logo_dt_clut224 : NULL; +} + +static void logo_dt_free(void) +{ + logo_dt_clut224.clut = NULL; + logo_dt_clut224.data = NULL; + + kfree(logo_dt_clut); + logo_dt_clut = NULL; + + kfree(logo_dt_data); + logo_dt_data = NULL; +} + +#else /* !CONFIG_LOGO_DT_CLUT224 */ + +static inline const struct linux_logo *logo_dt_find(void) +{ + return NULL; +} + +static inline void logo_dt_free(void) { } + +#endif /* CONFIG_LOGO_DT_CLUT224 */ + /* * Logos are located in the initdata, and will be freed in kernel_init. * Use late_init to mark the logos as freed to prevent any further use. @@ -32,6 +184,7 @@ static bool logos_freed; static int __init fb_logo_late_init(void) { logos_freed = true; + logo_dt_free(); return 0; } @@ -71,6 +224,10 @@ const struct linux_logo * __ref fb_find_logo(int depth) } if (depth >= 8) { + /* A logo supplied by the device tree wins over the built-in ones */ + logo = logo_dt_find(); + if (logo) + return logo; #ifdef CONFIG_LOGO_LINUX_CLUT224 /* Generic Linux logo */ logo = &logo_linux_clut224; -- 2.39.5