I have two NVME drives that show up as 'unknown' in pcidump(8).
I did some searching: the Samsung 9100 Pro has a Presto (S4LY027)
controller and the Silicon Power US75 has a Maxio MAP1602 controller.

# pcidump 6:0:0
 6:0:0: Samsung S4LY027

# pcidump 1:0:0
 1:0:0: Maxio MAP1602

OK?

Kind regards,

Job

Index: pcidevs
===================================================================
RCS file: /cvs/src/sys/dev/pci/pcidevs,v
diff -u -p -r1.2143 pcidevs
--- pcidevs	24 Jul 2026 13:58:18 -0000	1.2143
+++ pcidevs	25 Jul 2026 21:47:01 -0000
@@ -355,6 +355,7 @@ vendor	TEKRAM2		0x1de1	Tekram
 vendor	RPI		0x1de4	Raspberry Pi
 vendor	AMPERE		0x1def	Ampere
 vendor	KIOXIA		0x1e0f	Kioxia
+vendor	MAXIO		0x1e4b	Maxio
 vendor	YMTC		0x1e49	YMTC
 vendor	SSSTC		0x1e95	SSSTC
 vendor	QUECTEL		0x1eac	Quectel
@@ -7788,6 +7789,9 @@ product KINGSTON NV2		0x5019	NV2
 /* Kioxia */
 product KIOXIA BG4		0x0001	BG4
 
+/* Maxio */
+product	MAXIO MAP1602		0x1602	MAP1602
+
 /* KTI */
 product KTI KTIE		0x3000	KTI
 
@@ -9418,6 +9422,7 @@ product SAMSUNG2 PM9A1_NVME	0xa80a	PM9A1
 product SAMSUNG2 PM9B1_NVME	0xa80b	PM9B1
 product SAMSUNG2 PM9C1_NVME	0xa80c	PM9C1
 product SAMSUNG2 PM9C1A_NVME	0xa80d	PM9C1a
+product SAMSUNG2 S4LY027_NVME	0xa810	S4LY027
 product SAMSUNG2 NVME_171X	0xa820	NVMe
 product SAMSUNG2 NVME_172X	0xa821	NVMe
 product SAMSUNG2 NVME_172X_A_B	0xa822	NVMe