> Without attached screen it has bios_efiinfo->fb_addr == 0 that leads to skip
> efifb by efifb_match.
Well, I still have this diff lying around, in need of testers...
Index: sys/arch/amd64/amd64/efifb.c
===================================================================
RCS file: /OpenBSD/src/sys/arch/amd64/amd64/efifb.c,v
diff -u -p -u -p -r1.34 efifb.c
--- sys/arch/amd64/amd64/efifb.c 15 Jul 2022 17:57:25 -0000 1.34
+++ sys/arch/amd64/amd64/efifb.c 10 Nov 2025 18:52:35 -0000
@@ -349,6 +349,15 @@ efifb_alloc_screen(void *v, const struct
}
int
+efifb_cnprobe(void)
+{
+ if (bios_efiinfo == NULL || bios_efiinfo->fb_addr == 0)
+ return (-1);
+
+ return (0);
+}
+
+int
efifb_cnattach(void)
{
if (bios_efiinfo == NULL || bios_efiinfo->fb_addr == 0)
Index: sys/arch/amd64/amd64/wscons_machdep.c
===================================================================
RCS file: /OpenBSD/src/sys/arch/amd64/amd64/wscons_machdep.c,v
diff -u -p -u -p -r1.14 wscons_machdep.c
--- sys/arch/amd64/amd64/wscons_machdep.c 14 Oct 2017 04:44:43 -0000
1.14
+++ sys/arch/amd64/amd64/wscons_machdep.c 10 Nov 2025 18:52:35 -0000
@@ -82,6 +82,25 @@ void
wscnprobe(struct consdev *cp)
{
int maj;
+ int display = 0;
+
+#if (NEFIFB > 0)
+ if (efifb_cnprobe() == 0)
+ display = 1;
+#endif
+#if (NVGA > 0)
+ if (!display && vga_cnprobe(X86_BUS_SPACE_IO, X86_BUS_SPACE_MEM) == 0)
+ display = 1;
+#endif
+#if (NPCDISPLAY > 0)
+ if (!display &&
+ pcdisplay_cnprobe(X86_BUS_SPACE_IO, X86_BUS_SPACE_MEM) == 0)
+ display = 1;
+#endif
+ if (!display) {
+ cp->cn_pri = CN_DEAD;
+ return;
+ }
/* locate the major number */
for (maj = 0; maj < nchrdev; maj++) {
Index: sys/arch/amd64/include/efifbvar.h
===================================================================
RCS file: /OpenBSD/src/sys/arch/amd64/include/efifbvar.h,v
diff -u -p -u -p -r1.10 efifbvar.h
--- sys/arch/amd64/include/efifbvar.h 4 May 2019 11:34:47 -0000 1.10
+++ sys/arch/amd64/include/efifbvar.h 10 Nov 2025 18:52:35 -0000
@@ -25,6 +25,7 @@ struct efifb_attach_args {
struct pci_attach_args;
+int efifb_cnprobe(void);
int efifb_cnattach(void);
void efifb_cnremap(void);
int efifb_is_console(struct pci_attach_args *);
Index: sys/dev/ic/vga.c
===================================================================
RCS file: /OpenBSD/src/sys/dev/ic/vga.c,v
diff -u -p -u -p -r1.74 vga.c
--- sys/dev/ic/vga.c 27 May 2021 23:24:40 -0000 1.74
+++ sys/dev/ic/vga.c 10 Nov 2025 18:52:35 -0000
@@ -571,6 +571,15 @@ vga_extended_attach(struct device *self,
}
int
+vga_cnprobe(bus_space_tag_t iot, bus_space_tag_t memt)
+{
+ if (!vga_common_probe(iot, memt))
+ return (ENXIO);
+
+ return (0);
+}
+
+int
vga_cnattach(bus_space_tag_t iot, bus_space_tag_t memt, int type, int check)
{
uint32_t defattr;
Index: sys/dev/ic/vgavar.h
===================================================================
RCS file: /OpenBSD/src/sys/dev/ic/vgavar.h,v
diff -u -p -u -p -r1.13 vgavar.h
--- sys/dev/ic/vgavar.h 26 Jul 2015 03:17:07 -0000 1.13
+++ sys/dev/ic/vgavar.h 10 Nov 2025 18:52:35 -0000
@@ -187,6 +187,7 @@ struct vga_config *
vga_extended_attach(struct device *, bus_space_tag_t, bus_space_tag_t,
int, paddr_t (*)(void *, off_t, int));
int vga_is_console(bus_space_tag_t, int);
+int vga_cnprobe(bus_space_tag_t, bus_space_tag_t);
int vga_cnattach(bus_space_tag_t, bus_space_tag_t, int, int);
struct wsscreen_descr;
Index: sys/dev/isa/pcdisplay.c
===================================================================
RCS file: /OpenBSD/src/sys/dev/isa/pcdisplay.c,v
diff -u -p -u -p -r1.15 pcdisplay.c
--- sys/dev/isa/pcdisplay.c 6 Apr 2022 18:59:28 -0000 1.15
+++ sys/dev/isa/pcdisplay.c 10 Nov 2025 18:52:35 -0000
@@ -286,6 +286,16 @@ pcdisplay_attach(struct device *parent,
int
+pcdisplay_cnprobe(bus_space_tag_t iot, bus_space_tag_t memt)
+{
+ if (pcdisplay_probe_col(iot, memt))
+ return (0);
+ if (pcdisplay_probe_mono(iot, memt))
+ return (0);
+ return (ENXIO);
+}
+
+int
pcdisplay_cnattach(bus_space_tag_t iot, bus_space_tag_t memt)
{
int mono;
Index: sys/dev/isa/pcdisplayvar.h
===================================================================
RCS file: /OpenBSD/src/sys/dev/isa/pcdisplayvar.h,v
diff -u -p -u -p -r1.4 pcdisplayvar.h
--- sys/dev/isa/pcdisplayvar.h 2 Apr 2004 04:39:51 -0000 1.4
+++ sys/dev/isa/pcdisplayvar.h 10 Nov 2025 18:52:35 -0000
@@ -27,4 +27,5 @@
*
*/
+int pcdisplay_cnprobe(bus_space_tag_t, bus_space_tag_t);
int pcdisplay_cnattach(bus_space_tag_t, bus_space_tag_t);
