From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 52654489FAA; Fri, 2 Oct 2026 11:09:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790939400; cv=none; b=cHVN8JR+ReN4bQDDgSSlurO3r80HH34SDyl/nfONb+TPG5uzmLs8amMkG689rVJ8wOozuxVk5KUWaIpUDJAnQRt176PW2JzGxG7wVM+Tq960BZN174duO0t8G0nd2Hr6lhSOYfg5htcPx/VwTdKjZxTu7gfp4GaCXZtvEk8M4h8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790939400; c=relaxed/simple; bh=2Ye0k/fMhA8sGXWiT6C167fD6+fjCgRwOSywcm4S5So=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BI4O0mLexgZA3Ef/unzsBR11H0hjxJC3Oq+V/zGmCc+tbmbMm08GauepKhFVVryQaeSlYaGUgF50+xONK0FgA9FNdZE+5mKvp/CvRyyaDzn64aWUmcu/D01njaoKonexdy+n+vM60MUHkCHolcfwe2ptq2l/GPfg9RDRXrR5x5M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eJH2awXq; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="eJH2awXq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 97CB71F00899; Fri, 2 Oct 2026 11:09:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790939394; bh=Lq494l7k0PYr4jhdwg0brPjiodVedpmKQWhUq4sS3Ns=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=eJH2awXqh5iPgFosyZgJMsqgQH08OlvFImEGDOYBxyYHhM4Xk09eDjMqr4EkGd075 kCJTmM2aw80DgCMJOvl+KmCV6rY9Rvs9HyTihFtKCruwvgqS3TiKXvL6K51jq8/4bO jO3QmPq9Ebx/S9/3u/QgAafdbacbH5HdHBzH8HJm9RMUS0pBSFTXui7W5vAVzkcJR1 S7S58K/+VEgmEZNmgXaDInmM7Jwwd3FidelI08X66xN9AkOfkyks/UQpE+KGjVvYt8 dTUl87NRKEVfy3BRu7xUqt1AHDsagxxWIt0Q4yAdaiFr/JeYxwKbL/PQ3P/G4GPnem SswZX6zrxwZkA== From: Claudiu Beznea To: lpieralisi@kernel.org, kwilczynski@kernel.org, mani@kernel.org, robh@kernel.org, bhelgaas@google.com, p.zabel@pengutronix.de, 18255117159@163.com Cc: claudiu.beznea@tuxon.dev, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Claudiu Beznea , stable@vger.kernel.org, Lad Prabhakar Subject: [PATCH v5 2/9] PCI: rzg3s-host: Fix runtime PM handling in the NOIRQ suspend/resume phase Date: Fri, 2 Oct 2026 14:09:28 +0300 Message-ID: <20261002110935.2004349-3-claudiu.beznea@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20261002110935.2004349-1-claudiu.beznea@kernel.org> References: <20261002110935.2004349-1-claudiu.beznea@kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Claudiu Beznea The runtime PM documentation states the following: - During system suspend, pm_runtime_get_noresume() is called for every device right before executing the subsystem-level .prepare() callback (in device_prepare()). In addition, the PM core disables runtime PM for every device right before executing the subsystem-level .suspend_late() callback (in device_suspend_late()). - During system resume, pm_runtime_enable() is called for every device right after executing the subsystem-level .resume_early() callback (in device_resume_early()), and pm_runtime_put() is called right after executing the subsystem-level .complete() callback (in device_complete()). The driver's .suspend_noirq() callback is invoked after .suspend_late(), while .resume_noirq() is invoked before .resume_early(). If: - the device is not part of the wake-up path, and - its runtime PM status is not RPM_SUSPENDED, the generic power domain .suspend_noirq()/.resume_noirq() callbacks (genpd_suspend_noirq()/genpd_resume_noirq()) invoke the driver's .suspend_noirq()/.resume_noirq() callbacks and call genpd_stop_dev()/genpd_start_dev() before and after them, respectively. Calling genpd_stop_dev()/genpd_start_dev() allows devices whose power is controlled by generic power domains to be powered off and on during system suspend and resume, even though their runtime PM usage count does not reach zero. Since the runtime PM usage count is incremented in device_prepare() and decremented in device_complete(), runtime PM operations performed from the driver's .suspend_noirq()/.resume_noirq() callbacks are no-ops. The actual power transitions are handled by the generic power domain .suspend_noirq()/.resume_noirq() callbacks. Moreover, attempting to runtime resume a device while runtime PM is disabled may return -EACCES. This may cause system resume to fail when resuming after a failed Root Port reset, as described in a subsequent patch adding hot-plug support. Remove the runtime PM calls from the driver's .suspend_noirq()/.resume_noirq() callbacks and rely on the generic power domain callbacks to power the device off and on. Fixes: 7ef502fb35b2 ("PCI: Add Renesas RZ/G3S host controller driver") Cc: stable@vger.kernel.org Reviewed-by: Lad Prabhakar Tested-by: Lad Prabhakar Signed-off-by: Claudiu Beznea --- Changes in v5: - collected tags Changes in v4: - simplified the comments in rzg3s_pcie_suspend_noirq()/rzg3s_pcie_resume_noirq() Changes in v3: - none, this patch is new drivers/pci/controller/pcie-rzg3s-host.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) diff --git a/drivers/pci/controller/pcie-rzg3s-host.c b/drivers/pci/controller/pcie-rzg3s-host.c index e1105b1f2652..0ef49bb5ab1a 100644 --- a/drivers/pci/controller/pcie-rzg3s-host.c +++ b/drivers/pci/controller/pcie-rzg3s-host.c @@ -1961,19 +1961,18 @@ static int rzg3s_pcie_suspend_noirq(struct device *dev) if (ret) goto config_reinit; - ret = pm_runtime_put_sync(dev); - if (ret) - goto power_resets_restore; + /* + * Since the power domain's genpd_suspend_noirq() will disable clocks, + * there is no need to manually invoke runtime PM API here. + */ ret = rzg3s_sysc_config_func(sysc, RZG3S_SYSC_FUNC_ID_RST_RSM_B, 0); if (ret) - goto rpm_resume; + goto power_resets_restore; return 0; /* Restore the previous state if any error happens */ -rpm_resume: - pm_runtime_resume_and_get(dev); power_resets_restore: reset_control_bulk_deassert(data->num_power_resets, host->power_resets); @@ -2011,13 +2010,14 @@ static int rzg3s_pcie_resume_noirq(struct device *dev) goto assert_rst_rsm_b; } - ret = pm_runtime_resume_and_get(dev); - if (ret) - goto assert_rst_rsm_b; + /* + * Since the power domain's genpd_resume_noirq() will enable clocks, + * there is no need to manually invoke runtime PM API here. + */ ret = rzg3s_pcie_power_resets_deassert(host); if (ret) - goto rpm_put; + goto assert_rst_rsm_b; ret = rzg3s_pcie_host_setup(host, rzg3s_pcie_msi_hw_setup, rzg3s_pcie_msi_hw_teardown); @@ -2033,8 +2033,6 @@ static int rzg3s_pcie_resume_noirq(struct device *dev) assert_power_resets: reset_control_bulk_assert(data->num_power_resets, host->power_resets); -rpm_put: - pm_runtime_put_sync(dev); assert_rst_rsm_b: rzg3s_sysc_config_func(sysc, RZG3S_SYSC_FUNC_ID_RST_RSM_B, 0); return ret; -- 2.43.0