From nobody Sun Feb 8 09:32:16 2026 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 BD4E2C001DD for ; Thu, 13 Jul 2023 13:17:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234772AbjGMNRl (ORCPT ); Thu, 13 Jul 2023 09:17:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51116 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231761AbjGMNRb (ORCPT ); Thu, 13 Jul 2023 09:17:31 -0400 Received: from michel.telenet-ops.be (michel.telenet-ops.be [IPv6:2a02:1800:110:4::f00:18]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 18EAC270A for ; Thu, 13 Jul 2023 06:17:25 -0700 (PDT) Received: from ramsan.of.borg ([IPv6:2a02:1810:ac12:ed40:6264:77e5:42e2:477d]) by michel.telenet-ops.be with bizsmtp id LdHN2A00d3wy6xv06dHNae; Thu, 13 Jul 2023 15:17:23 +0200 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtp (Exim 4.95) (envelope-from ) id 1qJwC3-001GrC-48; Thu, 13 Jul 2023 15:17:22 +0200 Received: from geert by rox.of.borg with local (Exim 4.95) (envelope-from ) id 1qJwCA-00GWyv-QU; Thu, 13 Jul 2023 15:17:22 +0200 From: Geert Uytterhoeven To: Javier Martinez Canillas , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH 7/8] drm/fb-helper: Add support for DRM_FORMAT_R1 Date: Thu, 13 Jul 2023 15:17:15 +0200 Message-Id: X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Add support for the monochrome light-on-dark buffer format (R1) to the fb helper, so this format can be used for fbdev emulation and for the text console. This avoids the overhead of using XR24 and the associated conversions on display hardware that supports only a simple monochrome format. R1 is very similar to C1 (monochrome indexed color), and shares the same depth and bpp. As drm_mode_legacy_fb_format() returns a format based on only depth and bpp, it cannot distinguish between R1 and C1. Hence drm_fb_helper_find_format() is modified to try to fall back to R1 if C1 is not supported. Signed-off-by: Geert Uytterhoeven Reviewed-by: Javier Martinez Canillas --- drivers/gpu/drm/drm_fb_helper.c | 41 ++++++++++++++++++++++++--------- 1 file changed, 30 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helpe= r.c index e870b2ce7a8625e3..1f1bfa764b6b9f00 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1130,7 +1130,7 @@ static void drm_fb_helper_fill_pixel_fmt(struct fb_va= r_screeninfo *var, { u8 depth =3D format->depth; =20 - if (format->is_color_indexed) { + if (format->format =3D=3D DRM_FORMAT_R1 || format->is_color_indexed) { var->red.offset =3D 0; var->green.offset =3D 0; var->blue.offset =3D 0; @@ -1236,6 +1236,7 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo = *var, case DRM_FORMAT_C1: case DRM_FORMAT_C2: case DRM_FORMAT_C4: + case DRM_FORMAT_R1: /* supported format with sub-byte pixels */ break; =20 @@ -1439,12 +1440,24 @@ int drm_fb_helper_pan_display(struct fb_var_screeni= nfo *var, } EXPORT_SYMBOL(drm_fb_helper_pan_display); =20 +static bool is_supported_format(uint32_t format, const uint32_t *formats, + size_t format_count) +{ + size_t i; + + for (i =3D 0; i < format_count; ++i) { + if (formats[i] =3D=3D format) + return true; + } + + return false; +} + static uint32_t drm_fb_helper_find_format(struct drm_fb_helper *fb_helper,= const uint32_t *formats, size_t format_count, uint32_t bpp, uint32_t depth) { struct drm_device *dev =3D fb_helper->dev; uint32_t format; - size_t i; =20 /* * Do not consider YUV or other complicated formats @@ -1457,10 +1470,12 @@ static uint32_t drm_fb_helper_find_format(struct dr= m_fb_helper *fb_helper, const if (!format) goto err; =20 - for (i =3D 0; i < format_count; ++i) { - if (formats[i] =3D=3D format) - return format; - } + if (is_supported_format(format, formats, format_count)) + return format; + + if (format =3D=3D DRM_FORMAT_C1 && + is_supported_format(DRM_FORMAT_R1, formats, format_count)) + return DRM_FORMAT_R1; =20 err: /* We found nothing. */ @@ -1680,11 +1695,15 @@ static int drm_fb_helper_single_fb_probe(struct drm= _fb_helper *fb_helper) } =20 static void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch, - bool is_color_indexed) + const struct drm_format_info *format) { info->fix.type =3D FB_TYPE_PACKED_PIXELS; - info->fix.visual =3D is_color_indexed ? FB_VISUAL_PSEUDOCOLOR - : FB_VISUAL_TRUECOLOR; + if (format->format =3D=3D DRM_FORMAT_R1) + info->fix.visual =3D FB_VISUAL_MONO10; + else if (format->is_color_indexed) + info->fix.visual =3D FB_VISUAL_PSEUDOCOLOR; + else + info->fix.visual =3D FB_VISUAL_TRUECOLOR; info->fix.mmio_start =3D 0; info->fix.mmio_len =3D 0; info->fix.type_aux =3D 0; @@ -1707,6 +1726,7 @@ static void drm_fb_helper_fill_var(struct fb_info *in= fo, case DRM_FORMAT_C1: case DRM_FORMAT_C2: case DRM_FORMAT_C4: + case DRM_FORMAT_R1: /* supported format with sub-byte pixels */ break; =20 @@ -1747,8 +1767,7 @@ void drm_fb_helper_fill_info(struct fb_info *info, { struct drm_framebuffer *fb =3D fb_helper->fb; =20 - drm_fb_helper_fill_fix(info, fb->pitches[0], - fb->format->is_color_indexed); + drm_fb_helper_fill_fix(info, fb->pitches[0], fb->format); drm_fb_helper_fill_var(info, fb_helper, sizes->fb_width, sizes->fb_height); =20 --=20 2.34.1