Re: [PATCH v2 04/15] cxl/region: Calculate endpoint's region position during init

Gregory Price
2025-02-19T23:32:48Z

On Tue, Feb 18, 2025 at 02:23:45PM +0100, Robert Richter wrote:
> The calculation of an endpoint's position in a region traverses all
> ports up to the root port and determines the corresponding decoders
> for that particular address range. For address translation the HPA
> range must be recalculated between ports. In order to prepare the
> implementation of address translation, move code to
> cxl_endpoint_decoder_initialize() and reuse the existing iterator
> there.
>
> Signed-off-by: Robert Richter <rrichter@amd.com>
> ---
> drivers/cxl/core/region.c | 25 +++++++++++++++++++++----
> 1 file changed, 21 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index ad4a6ce37216..6f106bfa115f 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -1903,7 +1903,6 @@ static int cxl_region_sort_targets(struct cxl_region *cxlr)
> for (i = 0; i < p->nr_targets; i++) {
> struct cxl_endpoint_decoder *cxled = p->targets[i];
>
> - cxled->pos = cxl_calc_interleave_pos(cxled);
> /*
> * Record that sorting failed, but still continue to calc
> * cxled->pos so that follow-on code paths can reliably
> @@ -3264,10 +3263,22 @@ static int cxl_endpoint_decoder_initialize(struct cxl_endpoint_decoder *cxled)
> struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
> struct cxl_port *iter = cxled_to_port(cxled);
> struct cxl_decoder *root, *cxld = &cxled->cxld;
> - struct range *hpa = &cxld->hpa_range;
> + struct range hpa = cxld->hpa_range;

I believe you have a build error here:

drivers/cxl/core/region.c: In function ‘cxl_endpoint_decoder_initialize’:
drivers/cxl/core/region.c:3286:51: error: incompatible type for argument 2 of ‘cxl_port_find_switch_decoder’
3286 | root = cxl_port_find_switch_decoder(iter, hpa);
| ^~~
| |
| struct range
drivers/cxl/core/region.c:3244:67: note: expected ‘struct range *’ but argument is of type ‘struct range’
3244 | cxl_port_find_switch_decoder(struct cxl_port *port, struct range *hpa)
| ~~~~~~~~~~~~~~^~~

Just a missed & later in the function

~Gregory