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 2A63FC433F5 for ; Tue, 8 Feb 2022 14:20:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378047AbiBHOUP (ORCPT ); Tue, 8 Feb 2022 09:20:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60310 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351022AbiBHOUM (ORCPT ); Tue, 8 Feb 2022 09:20:12 -0500 Received: from mail-vk1-f177.google.com (mail-vk1-f177.google.com [209.85.221.177]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA71CC03FECE; Tue, 8 Feb 2022 06:20:11 -0800 (PST) Received: by mail-vk1-f177.google.com with SMTP id v192so9856109vkv.4; Tue, 08 Feb 2022 06:20:11 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=tWsUC/Af6ywp4UcAlxa6QvBdBkZWz95sQEwSbu3EUOM=; b=qviQxYjbeOWp0843ZcdnIo+y4ui8xr8+d5RFlZ4vO9LqvLY7aNgrAEuF0Pu9k2+LkX aVMNog5c/XBMA2IEu32h8mknAoBQucFoDgXUg5eVqbp7hCbR5bgt66RiwwiHwQFs6xkn ESSp/noBgZdE0QMgCCxyo4SS5JlmEoK3Fikbqji4pwLqS+Ddlwy1EnweXmJFMOp2jJK3 s9/AvTEv0mlxt+42A2Juqg6N1el6fQ89rDnsXIk5gu1ri04Jg2UaDmJhUQntEa0tIzsu cBq+y2sSVZtwEL1S9LuhFmFO2rMBvbkLOHbINI7oK3MtUyf6MRY1xYTfT8C6i/k1LttM fQhw== X-Gm-Message-State: AOAM532ARZjYISPgZ5mHK75hvuuNW2UBWe3ooav1uLWrcI7nL3HwwFEf XkdYHv7OAYnh3VMzNPWvq5m/QGItcX04uw== X-Google-Smtp-Source: ABdhPJwNVJpS74KdYjuNT/DdBWlEgfiEbsLZQCTpCOvWFLt0cuyphOK9myV6EqAiLwQhdzAsX2qn7g== X-Received: by 2002:a05:6122:17a5:: with SMTP id o37mr1656708vkf.25.1644330010672; Tue, 08 Feb 2022 06:20:10 -0800 (PST) Received: from mail-vs1-f44.google.com (mail-vs1-f44.google.com. [209.85.217.44]) by smtp.gmail.com with ESMTPSA id g22sm2823278vsk.26.2022.02.08.06.20.09 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 08 Feb 2022 06:20:09 -0800 (PST) Received: by mail-vs1-f44.google.com with SMTP id a19so3513768vsi.2; Tue, 08 Feb 2022 06:20:09 -0800 (PST) X-Received: by 2002:a05:6102:34d9:: with SMTP id a25mr223540vst.68.1644330009205; Tue, 08 Feb 2022 06:20:09 -0800 (PST) MIME-Version: 1.0 References: <20220204134347.1187749-1-javierm@redhat.com> In-Reply-To: <20220204134347.1187749-1-javierm@redhat.com> From: Geert Uytterhoeven Date: Tue, 8 Feb 2022 15:19:58 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 0/4] drm/tiny: Add driver for Solomon SSD1307 OLED displays To: Javier Martinez Canillas Cc: Linux Kernel Mailing List , Andy Shevchenko , Daniel Vetter , Linux Fbdev development list , Sam Ravnborg , DRI Development , =?UTF-8?Q?Noralf_Tr=C3=B8nnes?= , Thomas Zimmermann , Maxime Ripard , Daniel Vetter , David Airlie , Lee Jones , Liam Girdwood , Maarten Lankhorst , Mark Brown , Maxime Ripard , Rob Herring , Thierry Reding , =?UTF-8?Q?Uwe_Kleine=2DK=C3=B6nig?= , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Linux PWM List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Javier, On Fri, Feb 4, 2022 at 2:43 PM Javier Martinez Canillas wrote: > This patch series adds a DRM driver for the Solomon OLED SSD1305, SSD1306, > SSD1307 and SSD1309 displays. It is a port of the ssd1307fb fbdev driver. I gave it a try on an Adafruit FeatherWing 128x32 OLED, connected to an OrangeCrab ECP5 FPGA board running a 64 MHz VexRiscv RISC-V softcore. Findings: - Kernel size increased by 349 KiB, - The "Memory:" line reports 412 KiB less memory, - On top of that, "free" shows ca. 92 KiB more memory in use after bootup. - The logo (I have a custom monochrome logo enabled) is no longer shown. - The screen is empty, with a (very very slow) flashing cursor in the middle of the screen, with a bogus long line next to it, which I can see being redrawn. - Writing text (e.g. hello) to /dev/tty0, I first see the text, followed by an enlargement of some of the characters. - "time ls" on the serial console (no files in the current directory, so nothing to print) increases from 0.86s to 1.92s, so the system is more loaded. As ssd1307fb relied on deferred I/O too, the slowdown might be (partly) due to redrawing of the visual artefacts mentioned above. So while the displays seems to be initialized correctly, it looks like there are some serious bugs in the conversion from xrgb8888 to monochrome. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds 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 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 CB81AC433EF for ; Tue, 8 Feb 2022 14:20:13 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D98FC10E192; Tue, 8 Feb 2022 14:20:12 +0000 (UTC) Received: from mail-vs1-f51.google.com (mail-vs1-f51.google.com [209.85.217.51]) by gabe.freedesktop.org (Postfix) with ESMTPS id 2656810E192 for ; Tue, 8 Feb 2022 14:20:12 +0000 (UTC) Received: by mail-vs1-f51.google.com with SMTP id a19so3513862vsi.2 for ; Tue, 08 Feb 2022 06:20:12 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=tWsUC/Af6ywp4UcAlxa6QvBdBkZWz95sQEwSbu3EUOM=; b=iaW9vCaO535JVhHGfMYgP2ckLiHiQrPtvoewCnkoMRr+xKgM/HdnEPvV/KUTn9V40g d9Jft+k/tKhBqXGRMn8TuacjyjmVR2XBnDRzXWFOtAbi7jmWGkL5yIDh1Ok22O9wOdpM uf7LBRmtx+h3fmkV11Tk0wW0R1rYR+7eaO2mwGbnA+lGvSwmsb5D8u1D5t67quhi1RDh ZF4UIDyqWy9VgB+AXNHTctYzkXy7wtamarxfzCqwerSJG2m6n7jNQpTs5S5Se+cGM4er R85aKARIkQFPGVtGjS/y9UwXIER8IgeQSXmYOBwHOliXH9cEtkNXDQT4BKlJ45dGuUBb iAEQ== X-Gm-Message-State: AOAM532a30C16zi22nPYobL8Ehi3l2zGX0wqQGq7LBgbTRfCz1IiVGpT 7Ui6ed51lEt6wJngm1Tp7lYKpRwXjXI96A== X-Google-Smtp-Source: ABdhPJwQV25pFNCdJR4nAqKNOK/XOtyJsMJp/6CNXi459b8E7m1cO6kxr7rGGccXPfIp3gEVxxWtmg== X-Received: by 2002:a05:6102:31a5:: with SMTP id d5mr1474697vsh.69.1644330010425; Tue, 08 Feb 2022 06:20:10 -0800 (PST) Received: from mail-vs1-f43.google.com (mail-vs1-f43.google.com. [209.85.217.43]) by smtp.gmail.com with ESMTPSA id x47sm2888387uac.16.2022.02.08.06.20.09 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 08 Feb 2022 06:20:09 -0800 (PST) Received: by mail-vs1-f43.google.com with SMTP id t184so3521104vst.13 for ; Tue, 08 Feb 2022 06:20:09 -0800 (PST) X-Received: by 2002:a05:6102:34d9:: with SMTP id a25mr223540vst.68.1644330009205; Tue, 08 Feb 2022 06:20:09 -0800 (PST) MIME-Version: 1.0 References: <20220204134347.1187749-1-javierm@redhat.com> In-Reply-To: <20220204134347.1187749-1-javierm@redhat.com> From: Geert Uytterhoeven Date: Tue, 8 Feb 2022 15:19:58 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 0/4] drm/tiny: Add driver for Solomon SSD1307 OLED displays To: Javier Martinez Canillas Content-Type: text/plain; charset="UTF-8" X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Linux Fbdev development list , Linux PWM List , David Airlie , Daniel Vetter , Mark Brown , Linux Kernel Mailing List , DRI Development , Liam Girdwood , Rob Herring , =?UTF-8?Q?Noralf_Tr=C3=B8nnes?= , Thierry Reding , Maxime Ripard , Thomas Zimmermann , =?UTF-8?Q?Uwe_Kleine=2DK=C3=B6nig?= , Lee Jones , Andy Shevchenko , Sam Ravnborg Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Javier, On Fri, Feb 4, 2022 at 2:43 PM Javier Martinez Canillas wrote: > This patch series adds a DRM driver for the Solomon OLED SSD1305, SSD1306, > SSD1307 and SSD1309 displays. It is a port of the ssd1307fb fbdev driver. I gave it a try on an Adafruit FeatherWing 128x32 OLED, connected to an OrangeCrab ECP5 FPGA board running a 64 MHz VexRiscv RISC-V softcore. Findings: - Kernel size increased by 349 KiB, - The "Memory:" line reports 412 KiB less memory, - On top of that, "free" shows ca. 92 KiB more memory in use after bootup. - The logo (I have a custom monochrome logo enabled) is no longer shown. - The screen is empty, with a (very very slow) flashing cursor in the middle of the screen, with a bogus long line next to it, which I can see being redrawn. - Writing text (e.g. hello) to /dev/tty0, I first see the text, followed by an enlargement of some of the characters. - "time ls" on the serial console (no files in the current directory, so nothing to print) increases from 0.86s to 1.92s, so the system is more loaded. As ssd1307fb relied on deferred I/O too, the slowdown might be (partly) due to redrawing of the visual artefacts mentioned above. So while the displays seems to be initialized correctly, it looks like there are some serious bugs in the conversion from xrgb8888 to monochrome. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds