Re: [PATCH 0/3] Add UFS Host driver support for SpacemiT K3 SoC

From: Yixun Lan <dlan@kernel.org>
To: Anirudh Srinivasan <asrinivasan@oss.tenstorrent.com>
Cc: Alim Akhtar <alim.akhtar@samsung.com>,
	Avri Altman <avri.altman@sandisk.com>,
	Bart Van Assche <bvanassche@acm.org>,
	Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>,
	"James E.J. Bottomley" <James.Bottomley@hansenpartnership.com>,
	"Martin K. Petersen" <martin.petersen@oracle.com>,
	Philipp Zabel <p.zabel@pengutronix.de>,
	Paul Walmsley <pjw@kernel.org>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Alexandre Ghiti <alex@ghiti.fr>,
	linux-scsi@vger.kernel.org, devicetree@vger.kernel.org,
	linux-riscv@lists.infradead.org, spacemit@lists.linux.dev,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/3] Add UFS Host driver support for SpacemiT K3 SoC
Date: Mon, 13 Jul 2026 23:57:42 +0000	[thread overview]
Message-ID: <20260713235742-GKE106000@kernel.org> (raw)
In-Reply-To: <CAEev2e-g3bZcohFf_7b5CaVyi0BeWi5uwLGj6MuhQXp16jiyEQ@mail.gmail.com>

Hi Anirudh,

On 09:56 Mon 13 Jul     , Anirudh Srinivasan wrote:
> Hi Yixun,
> 
> On Mon, Jul 13, 2026 at 7:38 AM Yixun Lan <dlan@kernel.org> wrote:
> >
> > Hi Anirudh,
> >
> > On 22:40 Sun 12 Jul     , Anirudh Srinivasan wrote:
> > > Hi Yixun,
> > >
> > > On Thu, Jul 02, 2026 at 02:31:34AM +0000, Yixun Lan wrote:
> > > > This series try to add UFS support for SpacemiT K3 SoC, the controller
> > > > components consists of System Bus Interface Unit, UFS Host Controller
> > > > Interface, UFS Transport Protocol Layer, UFS Host Registers, Device
> > > > Management Entity (DME), Transport Layer, Network Layer, Data Link
> > > > Layer, PHY Adapter Layer, and M-PHY Interface. A more detail functional
> > > > block diagram can be found in SpacemiT website, chapter 9.7.3 [1]
> > > >
> > > > Please note, in order to test this driver, the UFS clock driver[2] here
> > > > should be applied first as a prerequisite patch.
> > > >
> > > > One known issue is that the device will occasionally raise BKOPS interrupt
> > > > when doing some high load test, log from dmesg shows
> > > >
> > > > [  806.710763] ufshcd-spacemit c0e00000.ufshc: ufshcd_bkops_exception_event_handler: device raised urgent BKOPS exception for bkops status 1
> > > >
> > > > Link: https://spacemit.com/community/document/info?nodepath=hardware/key_stone/k3/k3_docs/k3_usermanual/09_memory_storage.md&lang=en [1]
> > > > Link: https://lore.kernel.org/all/20260630-06-clk-ufs-support-v1-0-cf7521d1d0fe@kernel.org/ [2]
> > > > Signed-off-by: Yixun Lan <dlan@kernel.org>
> > >
> > > I see this during probe on a k3-pico-itx. Does the UFS chip on board
> > > have an RPMB block on it? Is this error of any concern.
> > >
> > It's probably true of having a RPMB block, but not used in K3 platform, so can ignore
> >
> > > [    5.957864] ufshcd-spacemit c0e00000.ufshc: ufshcd_scsi_add_wlus: BOOT WLUN not found
..
> > > [    5.963319] bus_add_device: cannot add device 'ufs_rpmb0' to unregistered bus 'ufs_rpmb'

Just checked code under drivers/ufs/, and couldn't find where ufs_rpmb bus is registered,
so this kind of warning/error message is expected, or could UFS maintainer confirm this?

> > > [    5.971155] ufshcd-spacemit c0e00000.ufshc: Failed to register UFS RPMB device 0
> > >
> > Maybe disable CONFIG_RPMB to silent this? I've not tested this option locally
> 
> I'm testing on a distro defconfig, so it has this option enabled.
> 
> Is there anything we can do in the driver to have it ignore the RPMB?

No, but why not disable CONFIG_RPMB in the first place

> If the error is a red-herring, we shouldn't be displaying it at all in
> the first place.
> 

Either fix the code or just ignore it..

-- 
Yixun Lan (dlan)