cxl_calc_interleave_pos() uses the endpoint decoder's HPA range to
determine its interleaving position. This requires the endpoint
decoders to be an SPA, which is not the case for systems that need
address translation.
Add a separate @range argument to function cxl_calc_interleave_pos()
to specify the address range. Now it is possible to pass the SPA
translated address range of an endpoint decoder to function
cxl_calc_interleave_pos().
Patch is a prerequisite to implement address translation.
Signed-off-by: Robert Richter <rrichter@amd.com>
---
drivers/cxl/core/region.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index 8ccc171ac724..106692f1e310 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -1844,11 +1844,11 @@ static int find_pos_and_ways(struct cxl_port *port, struct range *range,
* Return: position >= 0 on success
* -ENXIO on failure
*/
-static int cxl_calc_interleave_pos(struct cxl_endpoint_decoder *cxled)
+static int cxl_calc_interleave_pos(struct cxl_endpoint_decoder *cxled,
+ struct range *range)
{
struct cxl_port *iter, *port = cxled_to_port(cxled);
struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
- struct range *range = &cxled->cxld.hpa_range;
int parent_ways = 0, parent_pos = 0, pos = 0;
int rc;
@@ -1909,7 +1909,7 @@ 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);
+ cxled->pos = cxl_calc_interleave_pos(cxled, &cxlr->hpa_range);
/*
* Record that sorting failed, but still continue to calc
* cxled->pos so that follow-on code paths can reliably
@@ -2093,7 +2093,7 @@ static int cxl_region_attach(struct cxl_region *cxlr,
struct cxl_endpoint_decoder *cxled = p->targets[i];
int test_pos;
- test_pos = cxl_calc_interleave_pos(cxled);
+ test_pos = cxl_calc_interleave_pos(cxled, &cxlr->hpa_range);
dev_dbg(&cxled->cxld.dev,
"Test cxl_calc_interleave_pos(): %s test_pos:%d cxled->pos:%d\n",
(test_pos == cxled->pos) ? "success" : "fail",
--
2.39.5On Fri, Sep 12, 2025 at 04:45:07PM +0200, Robert Richter wrote:
> cxl_calc_interleave_pos() uses the endpoint decoder's HPA range to
> determine its interleaving position. This requires the endpoint
> decoders to be an SPA, which is not the case for systems that need
> address translation.
>
> Add a separate @range argument to function cxl_calc_interleave_pos()
> to specify the address range. Now it is possible to pass the SPA
> translated address range of an endpoint decoder to function
> cxl_calc_interleave_pos().
>
> Patch is a prerequisite to implement address translation.
>
> Signed-off-by: Robert Richter <rrichter@amd.com>
> ---
> drivers/cxl/core/region.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index 8ccc171ac724..106692f1e310 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -1844,11 +1844,11 @@ static int find_pos_and_ways(struct cxl_port *port, struct range *range,
> * Return: position >= 0 on success
> * -ENXIO on failure
> */
> -static int cxl_calc_interleave_pos(struct cxl_endpoint_decoder *cxled)
> +static int cxl_calc_interleave_pos(struct cxl_endpoint_decoder *cxled,
> + struct range *range)
> {
> struct cxl_port *iter, *port = cxled_to_port(cxled);
> struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
> - struct range *range = &cxled->cxld.hpa_range;
> int parent_ways = 0, parent_pos = 0, pos = 0;
> int rc;
Will this work? Change the assignment rather than adding a parameter:
- struct range *range = &cxled->cxld.hpa_range;
+ struct range *range = &cxled->cxld.region->hpa_range;
>
> @@ -1909,7 +1909,7 @@ 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);
> + cxled->pos = cxl_calc_interleave_pos(cxled, &cxlr->hpa_range);
> /*
> * Record that sorting failed, but still continue to calc
> * cxled->pos so that follow-on code paths can reliably
> @@ -2093,7 +2093,7 @@ static int cxl_region_attach(struct cxl_region *cxlr,
> struct cxl_endpoint_decoder *cxled = p->targets[i];
> int test_pos;
>
> - test_pos = cxl_calc_interleave_pos(cxled);
> + test_pos = cxl_calc_interleave_pos(cxled, &cxlr->hpa_range);
> dev_dbg(&cxled->cxld.dev,
> "Test cxl_calc_interleave_pos(): %s test_pos:%d cxled->pos:%d\n",
> (test_pos == cxled->pos) ? "success" : "fail",
> --
> 2.39.5
>
On 23.09.25 14:52:04, Alison Schofield wrote:
> On Fri, Sep 12, 2025 at 04:45:07PM +0200, Robert Richter wrote:
> > cxl_calc_interleave_pos() uses the endpoint decoder's HPA range to
> > determine its interleaving position. This requires the endpoint
> > decoders to be an SPA, which is not the case for systems that need
> > address translation.
> >
> > Add a separate @range argument to function cxl_calc_interleave_pos()
> > to specify the address range. Now it is possible to pass the SPA
> > translated address range of an endpoint decoder to function
> > cxl_calc_interleave_pos().
> >
> > Patch is a prerequisite to implement address translation.
> >
> > Signed-off-by: Robert Richter <rrichter@amd.com>
> > ---
> > drivers/cxl/core/region.c | 8 ++++----
> > 1 file changed, 4 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> > index 8ccc171ac724..106692f1e310 100644
> > --- a/drivers/cxl/core/region.c
> > +++ b/drivers/cxl/core/region.c
> > @@ -1844,11 +1844,11 @@ static int find_pos_and_ways(struct cxl_port *port, struct range *range,
> > * Return: position >= 0 on success
> > * -ENXIO on failure
> > */
> > -static int cxl_calc_interleave_pos(struct cxl_endpoint_decoder *cxled)
> > +static int cxl_calc_interleave_pos(struct cxl_endpoint_decoder *cxled,
> > + struct range *range)
> > {
> > struct cxl_port *iter, *port = cxled_to_port(cxled);
> > struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
> > - struct range *range = &cxled->cxld.hpa_range;
> > int parent_ways = 0, parent_pos = 0, pos = 0;
> > int rc;
>
> Will this work? Change the assignment rather than adding a parameter:
>
> - struct range *range = &cxled->cxld.hpa_range;
> + struct range *range = &cxled->cxld.region->hpa_range;
For cxl_region_sort_targets() it doesn't as the region is not yet
attached. This is the calling order:
cxl_region_sort_targets
cxl_calc_interleave_pos
# needs cxlr->hpa_range
cxl_region_attach_position
...
cxld->region = cxlr;
It would be nice if we can make this work and drop the argument. Will
take a look.
Thanks,
-Robert
On Fri, Sep 12, 2025 at 04:45:07PM +0200, Robert Richter wrote: > cxl_calc_interleave_pos() uses the endpoint decoder's HPA range to > determine its interleaving position. This requires the endpoint > decoders to be an SPA, which is not the case for systems that need > address translation. > > Add a separate @range argument to function cxl_calc_interleave_pos() > to specify the address range. Now it is possible to pass the SPA > translated address range of an endpoint decoder to function > cxl_calc_interleave_pos(). > > Patch is a prerequisite to implement address translation. > > Signed-off-by: Robert Richter <rrichter@amd.com> As with patch 4, maybe worth noting that this is simply a refactor, but otherwise Reviewed-by: Gregory Price <gourry@gourry.net>
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