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 96E7AC7EE23 for ; Mon, 5 Jun 2023 14:38:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234317AbjFEOiQ (ORCPT ); Mon, 5 Jun 2023 10:38:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58586 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232726AbjFEOiN (ORCPT ); Mon, 5 Jun 2023 10:38:13 -0400 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E7D3099; Mon, 5 Jun 2023 07:38:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1685975892; x=1717511892; h=date:from:to:cc:subject:in-reply-to:message-id: references:mime-version; bh=Ii0wAsvvPcH2RH0dwkgNRbrd5Rz5fLTuzH3e9FVwJYw=; b=gDLZkunr+Oe3K2eJ3U7xTt7knm5beCmPa4jgfy0Pro742/zs60qLsYOg dQ7UdFWF3Fran9JRsPcAbleT6J7A8egkxHfEXXsZU/FeBudxK0GPcIl1G xmKFQG16Db+WQ3mkI3Tt6W5eKz2eJXbB791wkqlia1xcKG9iGDLe7fpIE b1A8PHqXGPo++3S7L2DQN3QA8kkx+I60LjgLAiTViUMlU3WNUMt+yCLRU byN/f2nuxtuM6lG8hI3TRuletyZdmLIT8zoDOYbsDg3NqouhVrzAEyU+9 2vkhEe1DFKLwJ+51UgXP1Vu/fGXcdck0UZZS0SWhrlB+eEKU3/o4FqScl w==; X-IronPort-AV: E=McAfee;i="6600,9927,10732"; a="359695812" X-IronPort-AV: E=Sophos;i="6.00,217,1681196400"; d="scan'208";a="359695812" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jun 2023 07:38:12 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10732"; a="741750834" X-IronPort-AV: E=Sophos;i="6.00,217,1681196400"; d="scan'208";a="741750834" Received: from gfittedx-mobl.ger.corp.intel.com ([10.252.47.115]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jun 2023 07:38:07 -0700 Date: Mon, 5 Jun 2023 17:38:04 +0300 (EEST) From: =?ISO-8859-15?Q?Ilpo_J=E4rvinen?= To: =?ISO-8859-15?Q?Uwe_Kleine-K=F6nig?= cc: Tharun Kumar P , kernel@pengutronix.de, Geert Uytterhoeven , Rob Herring , Greg Kroah-Hartman , Helge Deller , Randy Dunlap , linuxppc-dev@lists.ozlabs.org, Nicholas Piggin , LKML , Kumaravel Thiagarajan , Christophe Leroy , linux-serial , Michael Ellerman , Matthew Gerlach , Jiri Slaby , Andy Shevchenko , Liang He Subject: Re: [PATCH v3 2/2] serial: 8250: Apply FSL workarounds also without SERIAL_8250_CONSOLE In-Reply-To: <20230605142225.75l6px3ep5ythkl6@pengutronix.de> Message-ID: <9fa2b513-24a5-2e37-9a63-1fd5f53fa92@linux.intel.com> References: <20230605130857.85543-1-u.kleine-koenig@pengutronix.de> <20230605130857.85543-3-u.kleine-koenig@pengutronix.de> <2d70e8b-7722-71e7-76f3-d27a2b2caa55@linux.intel.com> <20230605133445.vi762odw2v7pkrog@pengutronix.de> <20230605142225.75l6px3ep5ythkl6@pengutronix.de> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="8323329-1799272671-1685975891=:2703" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323329-1799272671-1685975891=:2703 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8BIT On Mon, 5 Jun 2023, Uwe Kleine-König wrote: > Hello Ilpo, > > On Mon, Jun 05, 2023 at 04:44:08PM +0300, Ilpo Järvinen wrote: > > On Mon, 5 Jun 2023, Uwe Kleine-König wrote: > > > On Mon, Jun 05, 2023 at 04:22:55PM +0300, Ilpo Järvinen wrote: > > > > On Mon, 5 Jun 2023, Uwe Kleine-König wrote: > > > > > > > > > The need to handle the FSL variant of 8250 in a special way is also > > > > > present without console support. So soften the dependency for > > > > > SERIAL_8250_FSL accordingly. Note that with the 8250 driver compiled as > > > > > a module, some devices still might not make use of the needed > > > > > workarounds. That affects the ports instantiated in > > > > > arch/powerpc/kernel/legacy_serial.c. > > > > > > > > > > This issue was identified by Dominik Andreas Schorpp. > > > > > > > > > > To cope for CONFIG_SERIAL_8250=m + CONFIG_SERIAL_8250_FSL=y, 8250_fsl.o > > > > > must be put in the same compilation unit as 8250_port.o because the > > > > > latter defines some functions needed in the former and so 8250_fsl.o > > > > > must not be built-in if 8250_port.o is available in a module. > > > > > > > > > > Acked-by: Ilpo Järvinen > > > > > Link: https://lore.kernel.org/r/20230531083230.2702181-1-u.kleine-koenig@pengutronix.de > > > > > Signed-off-by: Uwe Kleine-König > > > > > --- > > > > > drivers/tty/serial/8250/Kconfig | 2 +- > > > > > drivers/tty/serial/8250/Makefile | 2 +- > > > > > 2 files changed, 2 insertions(+), 2 deletions(-) > > > > > > > > > > diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig > > > > > index 5313aa31930f..10c09b19c871 100644 > > > > > --- a/drivers/tty/serial/8250/Kconfig > > > > > +++ b/drivers/tty/serial/8250/Kconfig > > > > > @@ -378,7 +378,7 @@ config SERIAL_8250_BCM2835AUX > > > > > > > > > > config SERIAL_8250_FSL > > > > > bool "Freescale 16550 UART support" if COMPILE_TEST && !(PPC || ARM || ARM64) > > > > > - depends on SERIAL_8250_CONSOLE > > > > > + depends on SERIAL_8250 > > > > > > > > Just one additional thought: After the adding the arch side > > > > workaround/hack, SERIAL_8250_FSL could become a tristate? > > > > > > I see no benefit for a module separate from 8250_base.ko. There are > > > dependencies in both directions between 8250_port.o and 8250_fsl.o[1]. > > > So in my book a bool SERIAL_8250_FSL that modifies 8250_base.ko (with > > > SERIAL_8250=m) is fine. > > > > > > Best regards > > > Uwe > > > > > > [1] 8250_port.o uses fsl8250_handle_irq() from 8250_fsl.o > > > > Is that after some fix which isn't in tty-next? I see only these: > > > > $ git grep -l fsl8250_handle_irq > > arch/powerpc/kernel/legacy_serial.c > > drivers/tty/serial/8250/8250_fsl.c > > drivers/tty/serial/8250/8250_of.c > > include/linux/serial_8250.h > > > > No users of fsl8250_handle_irq in 8250_port.c. > > Ah right, I was too quick: > > 8250_of.o uses fsl8250_handle_irq() from 8250_fsl.o > 8250_fsl.o uses serial8250_modem_status() from 8250_port.o (which is in 8250_base.o) > > > However linking 8250_fsl.o in 8250_of.o isn't a good solution either as > 8250_fsl.o should also be available with CONFIG_SERIAL_OF_PLATFORM > disabled to provide the ACPI driver. And as 8250_of.o already depends on > 8250_port.o (e.g. via serial8250_em485_config()) adding 8250_fsl.o > together with 8250_port.o into 8250_base.ko is fine and doesn't add new > dependencies. So we have dependencies one-way only: 8250_port /\ |\ \ 8250_fsl \ / /\ / 8250_of There's no loop here, both they be indepedent modules and configured independently (with a correct IS_*() in 8250_of.c). -- i. --8323329-1799272671-1685975891=:2703--