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Message-ID: <c498eb81-7b3f-a32c-02d7-572c17876a2d@arm.com>
Date:   Fri, 19 May 2023 13:40:04 +0100
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Subject: Re: [PATCH V3 6/6] coresight: platform: acpi: Ignore the absence of
 graph
To:     Anshuman Khandual <anshuman.khandual@arm.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        coresight@lists.linaro.org
Cc:     Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>,
        Steve Clevenger <scclevenger@os.amperecomputing.com>,
        Rob Herring <robh+dt@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        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
References: <20230519052149.1367814-1-anshuman.khandual@arm.com>
 <20230519052149.1367814-7-anshuman.khandual@arm.com>
From:   Suzuki K Poulose <suzuki.poulose@arm.com>
In-Reply-To: <20230519052149.1367814-7-anshuman.khandual@arm.com>
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On 19/05/2023 06:21, Anshuman Khandual wrote:
> From: Suzuki K Poulose <suzuki.poulose@arm.com>
> 
> Some components may not have graph connections for describing
> the trace path. e.g., ETE, where it could directly use the per
> CPU TRBE. Ignore the absence of graph connections
> 
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>

Please could you move this before the Patch 5, where we add
ACPI support for etm4x with system instructions ? That way
the support is up with that patch, without an error that
is fixed by this patch.

Suzuki


> ---
>   drivers/hwtracing/coresight/coresight-platform.c | 6 +++++-
>   1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c
> index 475899714104..c4b4fbde8550 100644
> --- a/drivers/hwtracing/coresight/coresight-platform.c
> +++ b/drivers/hwtracing/coresight/coresight-platform.c
> @@ -692,8 +692,12 @@ static int acpi_coresight_parse_graph(struct acpi_device *adev,
>   
>   	pdata->nr_inport = pdata->nr_outport = 0;
>   	graph = acpi_get_coresight_graph(adev);
> +	/*
> +	 * There are no graph connections, which is fine for some components.
> +	 * e.g., ETE
> +	 */
>   	if (!graph)
> -		return -ENOENT;
> +		return 0;
>   
>   	nlinks = graph->package.elements[2].integer.value;
>   	if (!nlinks)