The CXL RAS handlers do not currently log if the RAS registers are
unmapped. This is needed in order to help debug CXL error handling. Update
the CXL driver to log a warning message if the RAS register block is
unmapped during RAS error handling.

Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>

---
Changes v10->v11:
- Added Dave Jiang review-by
---
 drivers/cxl/core/ras.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/cxl/core/ras.c b/drivers/cxl/core/ras.c
index f65557e7bfa6..3454cf1a118d 100644
--- a/drivers/cxl/core/ras.c
+++ b/drivers/cxl/core/ras.c
@@ -286,8 +286,10 @@ static void cxl_handle_cor_ras(struct device *dev, void __iomem *ras_base)
 	void __iomem *addr;
 	u32 status;
 
-	if (!ras_base)
+	if (!ras_base) {
+		dev_warn_once(dev, "CXL RAS register block is not mapped");
 		return;
+	}
 
 	addr = ras_base + CXL_RAS_CORRECTABLE_STATUS_OFFSET;
 	status = readl(addr);
@@ -325,8 +327,10 @@ static bool cxl_handle_ras(struct device *dev, void __iomem *ras_base)
 	u32 status;
 	u32 fe;
 
-	if (!ras_base)
+	if (!ras_base) {
+		dev_warn_once(dev, "CXL RAS register block is not mapped");
 		return false;
+	}
 
 	addr = ras_base + CXL_RAS_UNCORRECTABLE_STATUS_OFFSET;
 	status = readl(addr);
-- 
2.51.0.rc2.21.ge5ab6b3e5a