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diff --git a/include/cxl/cxl.h b/include/cxl/cxl.h
index 19e5d883557a..f656fcd4945f 100644
--- a/include/cxl/cxl.h
+++ b/include/cxl/cxl.h

@@ -12,6 +12,25 @@ enum cxl_resource {
  	CXL_RES_PMEM,
  };
  
+/* Capabilities as defined for:
+ *
+ *	Component Registers (Table 8-22 CXL 3.1 specification)
+ *	Device Registers (8.2.8.2.1 CXL 3.1 specification)
+ *
+ * and currently being used for kernel CXL support.
+ */
+
+enum cxl_dev_cap {
+	/* capabilities from Component Registers */
+	CXL_DEV_CAP_RAS,
+	CXL_DEV_CAP_HDM,
+	/* capabilities from Device Registers */
+	CXL_DEV_CAP_DEV_STATUS,
+	CXL_DEV_CAP_MAILBOX_PRIMARY,
+	CXL_DEV_CAP_MEMDEV,
+	CXL_MAX_CAPS = 64  

Why set it to 64?  All the bitmaps etc will autosize so
you just need to ensure you use correct set_bit() and test_bit()
that are happy dealing with bitmaps of multiple longs.
 

Initially it was set to 32, but DECLARE_BITMAP uses unsigned long, so 
for initializing/zeroing the locally allocated bitmap in some functions, 
bitmap_clear had to use sizeof for the size, and I was suggested to 
define CXL_MAX_CAPS to 64 and use it instead, what seems cleaner.

It should never have been using sizeof() once it was a bitmap.
Just clear what is actually used and make sure no code assumes
any particular length of bitmap.  Then you will never have
to deal with changing it.

Then CXL_MAX_CAP just becomes last entry in this enum.

The only time this is becomes tricky with bitmaps is if you need
to set a bits in a constant bitmap as then you can't use the
set/get functions and have to assume something about the length.

Don't think that applies here.

Jonathan

 

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+};
+
  struct cxl_dev_state *cxl_accel_state_create(struct device *dev);
  
  void cxl_set_dvsec(struct cxl_dev_state *cxlds, u16 dvsec);