Re: [PATCH V5 6/6] coresight: etm4x: Add ACPI support in platform driver - Greg Kroah-Hartman

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>,
	linux-arm-kernel@lists.infradead.org, coresight@lists.linaro.org,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	scclevenger@os.amperecomputing.com,
	Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>,
	Rob Herring <robh+dt@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	Russell King <linux@armlinux.org.uk>, Len Brown <lenb@kernel.org>,
	Sudeep Holla <sudeep.holla@arm.com>,
	Lorenzo Pieralisi <lpieralisi@kernel.org>,
	Mathieu Poirier <mathieu.poirier@linaro.org>,
	Mike Leach <mike.leach@linaro.org>, Leo Yan <leo.yan@linaro.org>,
	devicetree@vger.kernel.org, linux-acpi@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH V5 6/6] coresight: etm4x: Add ACPI support in platform driver
Date: Tue, 27 Jun 2023 11:20:10 +0200	[thread overview]
Message-ID: <2023062736-spearhead-spinster-0fbf@gregkh> (raw)
In-Reply-To: <150b90b5-23fb-c115-6517-e6941b9b06df@arm.com>

On Tue, Jun 27, 2023 at 10:06:11AM +0100, Suzuki K Poulose wrote:
> Hi Greg,
> 
> On 29/05/2023 07:25, Anshuman Khandual wrote:
> > From: Suzuki K Poulose <suzuki.poulose@arm.com>
> > 
> > Drop ETM4X ACPI ID from the AMBA ACPI device list, and instead just move it
> > inside the new ACPI devices list detected and used via platform driver.
> > 
> > Cc: "Rafael J. Wysocki" <rafael@kernel.org>
> > Cc: Len Brown <lenb@kernel.org>
> > Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
> > Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
> > Cc: Mike Leach <mike.leach@linaro.org>
> > Cc: Leo Yan <leo.yan@linaro.org>
> > Cc: Sudeep Holla <sudeep.holla@arm.com>
> > Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
> > Cc: linux-acpi@vger.kernel.org
> > Cc: coresight@lists.linaro.org
> > Cc: linux-arm-kernel@lists.infradead.org
> > Cc: linux-kernel@vger.kernel.org
> > Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> (for ACPI specific changes)
> > Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> > Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
> > ---
> >   drivers/acpi/acpi_amba.c                           |  1 -
> >   drivers/hwtracing/coresight/coresight-etm4x-core.c | 10 ++++++++++
> >   2 files changed, 10 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/acpi/acpi_amba.c b/drivers/acpi/acpi_amba.c
> > index f5b443ab01c2..099966cbac5a 100644
> > --- a/drivers/acpi/acpi_amba.c
> > +++ b/drivers/acpi/acpi_amba.c
> > @@ -22,7 +22,6 @@
> >   static const struct acpi_device_id amba_id_list[] = {
> >   	{"ARMH0061", 0}, /* PL061 GPIO Device */
> >   	{"ARMH0330", 0}, /* ARM DMA Controller DMA-330 */
> > -	{"ARMHC500", 0}, /* ARM CoreSight ETM4x */
> >   	{"ARMHC501", 0}, /* ARM CoreSight ETR */
> >   	{"ARMHC502", 0}, /* ARM CoreSight STM */
> >   	{"ARMHC503", 0}, /* ARM CoreSight Debug */
> 
> This is a bit awkward request.
> 
> I would like to get your opinion on merging this to coresight tree.
> This change is removing the coresight ETMv4 from the ACPI AMBA
> scan list and moving it to the coresight driver. This change is
> essential for
> 1) Adding ACPI support for later versions of ETMv4 that are not AMBA
>    devices.
> 2) Adding power management support for AMBA ETMv4 with ACPI.
> 
> The above change has been reviewed by Sudeep (Arm64 ACPI reviewer), but
> hasn't been Acked by the ACPI maintainer (Rafael) even after a month of
> follow up with at least 4 reminders [0].
> 
> Are you happy with the Reviews from Sudeep and given the minimal
> change to the drivers/acpi/acpi_amba.c file ?

As we can't do anything now with the merge window open, please resend
after 6.5-rc1 is out and ask for the ACPI developers to ack this.

thanks,

greg k-h