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Date:   Mon, 3 Apr 2023 20:59:21 -0700
From:   Dan Williams <dan.j.williams@intel.com>
To:     Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        Liang Kan <kan.liang@linux.intel.com>,
        <linux-cxl@vger.kernel.org>, <peterz@infradead.org>
CC:     <mingo@redhat.com>, <acme@kernel.org>, <mark.rutland@arm.com>,
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        <linuxarm@huawei.com>, <linux-perf-users@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>,
        "Davidlohr Bueso" <dave@stgolabs.net>,
        Dave Jiang <dave.jiang@intel.com>
Subject: RE: [PATCH v4 1/5] cxl: Add function to count regblocks of a given
 type
Message-ID: <642ba099c2a4_29cc294ef@dwillia2-xfh.jf.intel.com.notmuch>
References: <20230330164556.31533-1-Jonathan.Cameron@huawei.com>
 <20230330164556.31533-2-Jonathan.Cameron@huawei.com>
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Jonathan Cameron wrote:
> Until the recently release CXL 3.0 specification, there
> was only ever one instance of any given register block pointed
> to by the Register Block Locator DVSEC. Now, the specification allows
> for multiple CXL PMU instances, each with their own register block.
> 
> To enable this add an index parameter to cxl_find_regblock()
> and use that to implement cxl_count_regblock().
> 
> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

If PMUs are the only consumer of multi-instance register blocks and all
other callers remain oblivious perhaps leave cxl_find_regblock() alone
and have it call a new cxl_find_regblock_instance() internally?

Otherwise, looks good to me.