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 3DD53CDB474 for ; Mon, 23 Oct 2023 07:44:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229820AbjJWHop (ORCPT ); Mon, 23 Oct 2023 03:44:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38434 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229650AbjJWHoo (ORCPT ); Mon, 23 Oct 2023 03:44:44 -0400 Received: from muru.com (muru.com [72.249.23.125]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 95C7ECC for ; Mon, 23 Oct 2023 00:44:42 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id 6ACD380BB; Mon, 23 Oct 2023 07:44:41 +0000 (UTC) Date: Mon, 23 Oct 2023 10:44:40 +0300 From: Tony Lindgren To: Thomas Richard Cc: gregkh@linuxfoundation.org, jirislaby@kernel.org, linux-serial@vger.kernel.org, gregory.clement@bootlin.com, u-kumar1@ti.com, d-gole@ti.com, thomas.petazzoni@bootlin.com, Vignesh R , Kevin Hilman Subject: Re: [PATCH] serial: 8250_omap: Set the console genpd always on if no console suspend Message-ID: <20231023074440.GS27774@atomide.com> References: <20231017130540.1149721-1-thomas.richard@bootlin.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231017130540.1149721-1-thomas.richard@bootlin.com> Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org Hi, Adding Kevin and Vignesh too in case they have better ideas on how to prevent the power domain from suspending for no_console_suspend kernel parameter. * Thomas Richard [231017 13:05]: > If the console suspend is disabled, the genpd of the console shall not > be powered-off during suspend. > Set the flag GENPD_FLAG_ALWAYS_ON to the corresponding genpd during > suspend, and restore the original value during the resume. > > Signed-off-by: Thomas Richard > --- > drivers/tty/serial/8250/8250_omap.c | 33 ++++++++++++++++++++++++----- > 1 file changed, 28 insertions(+), 5 deletions(-) > > diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c > index ca972fd37725..91a483dc460c 100644 > --- a/drivers/tty/serial/8250/8250_omap.c > +++ b/drivers/tty/serial/8250/8250_omap.c > @@ -27,6 +27,7 @@ > #include > #include > #include > +#include > > #include "8250.h" > > @@ -114,6 +115,12 @@ > /* RX FIFO occupancy indicator */ > #define UART_OMAP_RX_LVL 0x19 > > +/* > + * Copy of the genpd flags for the console. > + * Only used if console suspend is disabled > + */ > +static unsigned int genpd_flags_console; This should be priv->genpd_flags_console or something similar as the uarts in an always-on power domain may have different flags from other power domains. Other than that I'm fine with with unless other people have better ideas on how to handle this. Regards, Tony > struct omap8250_priv { > void __iomem *membase; > int line; > @@ -1617,6 +1624,7 @@ static int omap8250_suspend(struct device *dev) > { > struct omap8250_priv *priv = dev_get_drvdata(dev); > struct uart_8250_port *up = serial8250_get_port(priv->line); > + struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain); > int err = 0; > > serial8250_suspend_port(priv->line); > @@ -1627,8 +1635,19 @@ static int omap8250_suspend(struct device *dev) > if (!device_may_wakeup(dev)) > priv->wer = 0; > serial_out(up, UART_OMAP_WER, priv->wer); > - if (uart_console(&up->port) && console_suspend_enabled) > - err = pm_runtime_force_suspend(dev); > + if (uart_console(&up->port)) { > + if (console_suspend_enabled) > + err = pm_runtime_force_suspend(dev); > + else { > + /* > + * The pd shall not be powered-off (no console suspend). > + * Make copy of genpd flags before to set it always on. > + * The original value is restored during the resume. > + */ > + genpd_flags_console = genpd->flags; > + genpd->flags |= GENPD_FLAG_ALWAYS_ON; > + } > + } > flush_work(&priv->qos_work); > > return err; > @@ -1638,12 +1657,16 @@ static int omap8250_resume(struct device *dev) > { > struct omap8250_priv *priv = dev_get_drvdata(dev); > struct uart_8250_port *up = serial8250_get_port(priv->line); > + struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain); > int err; > > if (uart_console(&up->port) && console_suspend_enabled) { > - err = pm_runtime_force_resume(dev); > - if (err) > - return err; > + if (console_suspend_enabled) { > + err = pm_runtime_force_resume(dev); > + if (err) > + return err; > + } else > + genpd->flags = genpd_flags_console; > } > > serial8250_resume_port(priv->line); > -- > 2.39.2 >