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Date: Thu, 9 May 2024 22:31:39 -0700
From: Ira Weiny <ira.weiny@intel.com>
To: Dan Williams <dan.j.williams@intel.com>, Ira Weiny <ira.weiny@intel.com>,
	Jonathan Cameron <Jonathan.Cameron@huawei.com>
CC: Dave Jiang <dave.jiang@intel.com>, Fan Ni <fan.ni@samsung.com>, "Navneet
 Singh" <navneet.singh@intel.com>, Dan Williams <dan.j.williams@intel.com>,
	Davidlohr Bueso <dave@stgolabs.net>, Alison Schofield
	<alison.schofield@intel.com>, Vishal Verma <vishal.l.verma@intel.com>,
	<linux-btrfs@vger.kernel.org>, <linux-cxl@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 06/26] cxl/port: Add Dynamic Capacity mode support to
 endpoint decoders
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Dan Williams wrote:
> Ira Weiny wrote:
> [..]
> > > > +	case CXL_DECODER_DC0 ... CXL_DECODER_DC7:
> > > > +		rc = dc_mode_to_region_index(mode);
> > > > +		if (rc < 0)
> > > > +			return rc;
> > > 
> > > Can't fail, so you could not bother checking..  Seems very unlikely
> > > that function will gain other error cases in the future.
> > 
> > Sure, done.
> 
> Can dc_mode_to_region_index() be dropped altogether? Is there any
> scenario where dc_mode_to_region_index() is really handling an anonymous
> @mode argument? I.e. just replace all dc_mode_to_region_index() with
> "mode - CXL_DECODER_DC0"?

Once we open up DC partitions to support multiple regions, no.

How about we remove the check in dc_mode_to_region_index() but keep the
function?  That makes it clear that we are converting from an enum to int
index?

Ira