My new toy has PCI UART but no legacy COM port:
puc0 at pci0 dev 26 function 0 "Intel C3000 UART" rev 0x11: ports: 16 com
com4 at puc0 port 0 apic 2 int 16: ns16550a, 16 byte fifo
BIOS redirects to "COM0(Pci Bus0,Dev26,Func0)" which becomes com4.
"set tty com0" or "set tty com4" at boot> both hang (expected, I guess,
no ISA port, PCI not enumerated yet).
probing: pc0 mem[640K 993M 924M 96M 892K 3M 14336M]
disk: hd0 hd1
>> OpenBSD/amd64 BOOTX64 3.70
boot> set tty com4
switching console to com4
Getty on tty04 works fine in multiuser.
probing: pc0 mem[640K 993M 924M 96M 892K 3M 14336M]
disk: hd0 hd1
>> OpenBSD/amd64 BOOTX64 3.70
boot> boot
booting hd0a:/bsd: 22534069+4744208+458880+0+1359872
[1978765+128+1515096+1204887]=0x203d700
entry point at 0x1001000
OpenBSD/amd64 (xxx) (tty04)
login:
Question: Is there any way to redirect kernel console to com4 after PCI
is up, or is console device fixed at boot? If it's fixed, I presume
that's a fundamental limitation?
I don't see a way to get BIOS to expose legacy COM, so just want to
confirm this is all I'm gonna see from this hardware.
Thanks
Greg
OpenBSD 7.8-current (GENERIC.MP) #192: Sun Dec 28 22:15:38 MST 2025
[email protected]:/usr/src/sys/arch/amd64/compile/GENERIC.MP
real mem = 17128718336 (16335MB)
avail mem = 16582578176 (15814MB)
random: good seed from bootblocks
mpath0 at root
scsibus0 at mpath0: 256 targets
mainbus0 at root
bios0 at mainbus0: SMBIOS rev. 3.0 @ 0x7f2ff000 (54 entries)
bios0: vendor American Megatrends Inc. version "5.13" date 02/21/2024
bios0: Default string QDNV01
efi0 at bios0: UEFI 2.6
efi0: American Megatrends rev 0x5000d
acpi0 at bios0: ACPI 6.1
acpi0: sleep states S0 S4 S5
acpi0: tables DSDT FACP FPDT FIDT MCFG WDAT APIC BDAT HPET UEFI SSDT DMAR SPCR
HEST BERT ERST EINJ WSMT
acpi0: wakeup devices PEX0(S4) PEX1(S4) PEX2(S4) PEX3(S4) PEX4(S4) PEX5(S4)
PEX6(S4) PEX7(S4) XHC1(S4) LAN0(S4) LAN1(S4) LAN2(S4) LAN3(S4)
acpitimer0 at acpi0: 3579545 Hz, 24 bits
acpimcfg0 at acpi0
acpimcfg0: addr 0xe0000000, bus 0-255
acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat
cpu0 at mainbus0: apid 0 (boot processor)
cpu0: Intel(R) Atom(TM) CPU C3758R @ 2.40GHz, 2400.01 MHz, 06-5f-01, patch
0000003e
cpu0: cpuid 1
edx=bfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
ecx=47f8ebbf<SSE3,PCLMUL,DTES64,MWAIT,DS-CPL,VMX,EST,TM2,SSSE3,SDBG,CX16,xTPR,PDCM,SSE4.1,SSE4.2,x2APIC,MOVBE,POPCNT,DEADLINE,AES,XSAVE,RDRAND>
cpu0: cpuid 6 eax=55<SENSOR,ARAT,PTS> ecx=9<EFFFREQ>
cpu0: cpuid 7.0
ebx=2294e283<FSGSBASE,TSC_ADJUST,SMEP,ERMS,MPX,RDSEED,SMAP,CLFLUSHOPT,PT,SHA>
edx=ac000400<MD_CLEAR,IBRS,IBPB,STIBP,SSBD>
cpu0: cpuid a vers=4, gp=4, gpwidth=48, ff=3, ffwidth=48
cpu0: cpuid d.1 eax=f<XSAVEOPT,XSAVEC,XGETBV1,XSAVES>
cpu0: cpuid 80000001 edx=2c100800<NXE,PAGE1GB,RDTSCP,LONG> ecx=101<LAHF,3DNOWP>
cpu0: cpuid 80000007 edx=100<ITSC>
cpu0: msr
10a=14000c69<SKIP_L1DFL,MDS_NO,IF_PSCHANGE,MISC_PKG_CT,ENERGY_FILT,GDS_NO,RFDS_CLEAR>
cpu0: 24KB 64b/line 6-way D-cache, 32KB 64b/line 8-way I-cache, 2MB 64b/line
16-way L2 cache
cpu0: smt 0, core 0, package 0
mtrr: Pentium Pro MTRR support, 10 var ranges, 88 fixed ranges
cpu0: apic clock running at 25MHz
cpu0: mwait min=64, max=64, C-substates=0.2.0.2, IBE
