Unless and until accelerator (type-2) drivers start registering for
CXL.mem mapping services from the CXL subsystem core, initialize idle
HDM decoders to the "expander" type. I.e. the only CXL devices using the
CXL core presently are those implementing the CXL 2.0 Type-3 memory
expander device class code that the cxl_pci driver claims.

Signed-off-by: Dan Williams <[email protected]>
---
 drivers/cxl/core/hdm.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c
index 672bf3e97811..7b58f6911523 100644
--- a/drivers/cxl/core/hdm.c
+++ b/drivers/cxl/core/hdm.c
@@ -474,6 +474,17 @@ static int init_hdm_decoder(struct cxl_port *port, struct 
cxl_decoder *cxld,
                cxld->flags |= CXL_DECODER_F_ENABLE;
                if (ctrl & CXL_HDM_DECODER0_CTRL_LOCK)
                        cxld->flags |= CXL_DECODER_F_LOCK;
+               if (FIELD_GET(CXL_HDM_DECODER0_CTRL_TYPE, ctrl))
+                       cxld->target_type = CXL_DECODER_EXPANDER;
+               else
+                       cxld->target_type = CXL_DECODER_ACCELERATOR;
+       } else {
+               /* unless / until type-2 drivers arrive, assume type-3 */
+               if (FIELD_GET(CXL_HDM_DECODER0_CTRL_TYPE, ctrl) == 0) {
+                       ctrl |= CXL_HDM_DECODER0_CTRL_TYPE;
+                       writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(which));
+               }
+               cxld->target_type = CXL_DECODER_EXPANDER;
        }
        rc = cxl_to_ways(FIELD_GET(CXL_HDM_DECODER0_CTRL_IW_MASK, ctrl),
                         &cxld->interleave_ways);
@@ -488,11 +499,6 @@ static int init_hdm_decoder(struct cxl_port *port, struct 
cxl_decoder *cxld,
        if (rc)
                return rc;
 
-       if (FIELD_GET(CXL_HDM_DECODER0_CTRL_TYPE, ctrl))
-               cxld->target_type = CXL_DECODER_EXPANDER;
-       else
-               cxld->target_type = CXL_DECODER_ACCELERATOR;
-
        if (!cxled) {
                target_list.value =
                        ioread64_hi_lo(hdm + CXL_HDM_DECODER0_TL_LOW(which));
-- 
2.36.1


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