[PATCH 3/3] cxl/hdm: Restore commit_end when decoder enumeration fails

commit_end tracks the highest committed decoder on a port. It gets
advanced before decoder enumeration is complete, so a later failure
leaves it pointing at a decoder that was never added. The next probe
then rejects decoder0 as out of order and enumeration fails.

Reset commit_end before enumerating so it is rebuilt from the decoders
actually committed on each probe.

Fixes: 176baefb2eb5 ("cxl/hdm: Commit decoder state to hardware")
Fixes: b777e9bec960 ("cxl/hdm: Emulate HDM decoder from DVSEC range registers")
Signed-off-by: Alison Schofield <[email protected]>
---
 drivers/cxl/core/hdm.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c
index 75d17120233d..0145d3db3107 100644
--- a/drivers/cxl/core/hdm.c
+++ b/drivers/cxl/core/hdm.c
@@ -1178,6 +1178,10 @@ static int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
 
 	cxl_settle_decoders(cxlhdm);
 
+	/* Reset to the none committed baseline for a fresh enumeration */
+	scoped_guard(rwsem_write, &cxl_rwsem.region)
+		port->commit_end = -1;
+
 	for (i = 0; i < cxlhdm->decoder_count; i++) {
 		int rc, target_count = cxlhdm->target_count;
 		struct cxl_decoder *cxld;
-- 
2.37.3