From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 2C548370D78; Tue, 24 Mar 2026 08:45:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774341922; cv=none; b=RiPNMyniB+Rql4Fv6q3ipV28x6cQhMuidZzKmE2TnK3kTlNIduB3wgh7OmcbJWbCcrNt7SFTqs6b23cf61YH/D21AM2e9vvrCWFTy+CekRA/Tz3Hvv5+ZuWcnqBxZWnNdudBhb+5sR42aI1RDJPH5yBnVv2flarIa9hMgO2D3Us= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774341922; c=relaxed/simple; bh=PPl/rC2OPLdnK/BWcMFaxt/YnKgshXcEJ8ivDfLY7fY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=LA7CuVCO7AlKKfqJt5tOyPGJPDLp/NEU9EMfn2eG2sm9+0IOgztmlYxqUKOGWqbfanQ5qGollxODYjSBtQpgveRK2xWcFWtGKMyBQVQhB4qwYQk6ijn4iCosHMglXDj8raxzXQ9RokbkCBVdgcvgm1910tSwgxA9px9PW9q54Mo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eJqB4X8W; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="eJqB4X8W" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DCD75C19424; Tue, 24 Mar 2026 08:45:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774341921; bh=PPl/rC2OPLdnK/BWcMFaxt/YnKgshXcEJ8ivDfLY7fY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=eJqB4X8WYlPyGiXK2O72S3SKONpGWaKEpkxoGJ27JTZsE1lPhe7Q39be9Hv6pPMKG ALJEOMY/OdEkWXpEWlJJh/Pn7rwVLFl+J4a+4HDZWmuvWq53YjhiUQWc5bZ4K8OyND 7fOLFjcUMvSdOBDYTFMyude1IDU8Qkia0mG2sTLGykgzkF3zwFyw9zhDiPt2MNQb+Q gTRnKdOkcpoQBgC/ORayqvOFe5ZYYkE8tPxs+kH5msRm8S6U2hDEtVvEStWvfuI7cC vMEmsn2ByBeE/8+byN/E8XEAFD/FCiA0CJl0o8muSPEme+Zgdr/1o4eWjLnZESpfVH cqH8jFw1OGq8g== Date: Tue, 24 Mar 2026 09:45:16 +0100 From: Lorenzo Pieralisi To: Jon Hunter Cc: Manivannan Sadhasivam , mark.rutland@arm.com, bjorn.andersson@oss.qualcomm.com, konrad.dybcio@oss.qualcomm.com, mani@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Konrad Dybcio , Konrad Dybcio , Sudeep Holla , "linux-tegra@vger.kernel.org" Subject: Re: [PATCH] firmware: psci: Set pm_set_resume/suspend_via_firmware() for SYSTEM_SUSPEND Message-ID: References: <20251231162126.7728-1-manivannan.sadhasivam@oss.qualcomm.com> Precedence: bulk X-Mailing-List: linux-tegra@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Mon, Mar 23, 2026 at 10:10:00AM +0000, Jon Hunter wrote: > Hi Mark, Lorenzo, > > On 12/03/2026 19:00, Jon Hunter wrote: > > Hi all, > > > > On 31/12/2025 16:21, Manivannan Sadhasivam wrote: > > > From: Konrad Dybcio > > > > > > PSCI specification defines the SYSTEM_SUSPEND feature which enables the > > > firmware to implement the suspend to RAM (S2RAM) functionality by > > > transitioning the system to a deeper low power state. When the system > > > enters such state, the power to the peripheral devices might be > > > removed. So > > > the respective device drivers must prepare for the possible removal > > > of the > > > power by performing actions such as shutting down or resetting the device > > > in their system suspend callbacks. > > > > > > The Linux PM framework allows the platform drivers to convey this info to > > > device drivers by calling the pm_set_suspend_via_firmware() and > > > pm_set_resume_via_firmware() APIs. > > > > > > Hence, if the PSCI firmware supports SYSTEM_SUSPEND feature, call > > > the above > > > mentioned APIs in the psci_system_suspend_begin() and > > > psci_system_suspend_enter() callbacks. > > > > > > Signed-off-by: Konrad Dybcio > > > Reviewed-by: Sudeep Holla > > > [mani: reworded the description to be more elaborative] > > > Signed-off-by: Manivannan Sadhasivam > > > > > > --- > > > > > > This patch was part of an old series that didn't make it to mainline > > > due to > > > objections in the binding and exposing CPU_SUSPEND as S2RAM patches: > > > https://lore.kernel.org/all/20241028-topic-cpu_suspend_s2ram- > > > v1-0-9fdd9a04b75c@oss.qualcomm.com/ > > > > > > But this patch on its own is useful for platforms implementing the S2RAM > > > feature in PSCI firmware. So I picked it up, tested on Qcom X1E T14s and > > > resending it. > > > > > >   drivers/firmware/psci/psci.c | 10 ++++++++++ > > >   1 file changed, 10 insertions(+) > > > > > > diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c > > > index 38ca190d4a22..e73bae6cb23a 100644 > > > --- a/drivers/firmware/psci/psci.c > > > +++ b/drivers/firmware/psci/psci.c > > > @@ -539,12 +539,22 @@ static int psci_system_suspend(unsigned long > > > unused) > > >   static int psci_system_suspend_enter(suspend_state_t state) > > >   { > > > +    pm_set_resume_via_firmware(); > > > + > > >       return cpu_suspend(0, psci_system_suspend); > > >   } > > > +static int psci_system_suspend_begin(suspend_state_t state) > > > +{ > > > +    pm_set_suspend_via_firmware(); > > > + > > > +    return 0; > > > +} > > > + > > >   static const struct platform_suspend_ops psci_suspend_ops = { > > >       .valid          = suspend_valid_only_mem, > > >       .enter          = psci_system_suspend_enter, > > > +    .begin          = psci_system_suspend_begin, > > >   }; > > >   static void __init psci_init_system_reset2(void) > > > > > > I wanted to ask what the status of this patch is? > > > > It turns out that since commit f3ac2ff14834 ("PCI/ASPM: Enable all > > ClockPM and ASPM states for devicetree platforms"), this fix is also > > need for Tegra platforms that have NVMe devices to ensure that they are > > suspended as needed. There is some more background in this thread [0]. > > > Any feedback on this? I am not sure if this patch is purposely being > ignored, but if so, I would like to understand why. It fell through the cracks, apologies. Lorenzo