[PATCH v3 3/3] cxl/test: Assign one mock memdev a full-width serial number

Mock memdev serial numbers have historically been derived from
pdev->id, leaving them single-digit. As a result they never exercised
either the decimal-vs-hex security-key lookup or unsigned formatting
of large serial numbers.

Give one mock memdev a full-width serial with bit 63 set. This mirrors
real hardware (for example, Montage devices) and provides a test
device that exposes both the hexadecimal-vs-decimal and signed-vs-
unsigned formatting differences.

pdev->id 7 is unused by the auto-region topology so the larger serial
does not affect existing tests.

This enables adding a new test case to cxl-security.sh that verify
auto-unlock using a mock device whose serial exposes both formatting
differences.

Signed-off-by: Alison Schofield <[email protected]>
---
 tools/testing/cxl/test/mem.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c
index a1d170f88fee..42f5ffd29651 100644
--- a/tools/testing/cxl/test/mem.c
+++ b/tools/testing/cxl/test/mem.c
@@ -1714,6 +1714,7 @@ static int cxl_mock_mem_probe(struct platform_device *pdev)
 	struct cxl_mockmem_data *mdata;
 	struct cxl_mailbox *cxl_mbox;
 	struct cxl_dpa_info range_info = { 0 };
+	u64 serial;
 	int rc;
 
 	/* Increase async probe race window */
@@ -1740,7 +1741,19 @@ static int cxl_mock_mem_probe(struct platform_device *pdev)
 	if (rc)
 		return rc;
 
-	mds = cxl_memdev_state_create(dev, pdev->id + 1, 0);
+	/*
+	 * Mock serials have historically been derived from pdev->id and stayed
+	 * single-digit, so they never exercised either decimal-vs-hex key
+	 * lookup or unsigned formatting. Give one mock device a full-width
+	 * serial with bit 63 set, matching real hardware such as Montage CXL
+	 * devices. pdev->id 7 is unused by the auto-region topology.
+	 */
+	if (pdev->id == 7)
+		serial = 0x8a34567890abcdef;
+	else
+		serial = pdev->id + 1;
+
+	mds = cxl_memdev_state_create(dev, serial, 0);
 	if (IS_ERR(mds))
 		return PTR_ERR(mds);
 
-- 
2.37.3