Hi all! On Thu, May 03, 2018 at 05:49:31PM +0200, Felix Deichmann wrote:
Interesting point. Look for 16-bit "Configuration Register" (CFG) at physical address 0x25800000. Bit 3, ALCON, reflects the "Alternate Console" S3 switch, and is 1 when the serial console is to be used. See KA49 Processor Module Specification V 1.1, chapter 5.2. However, the CFG register is described as read-only!
After some studying I finally could unveil what was happening. The solution is rather simple:
--- sys/arch/vax/vsa/dz_vsbus.c.orig 2018-07-09 00:25:11.000000000 -0300 +++ sys/arch/vax/vsa/dz_vsbus.c 2018-07-09 00:25:23.000000000 -0300 @@ -263,7 +263,7 @@ case VAX_BTYP_49: ioaddr = DZ_CSR_KA49; - diagcons = (vax_confdata & 8 ? 3 : 0); + diagcons = 3; break; case VAX_BTYP_53:Thanks for Felix Deichmann, Anders Magnusson and others for the help! :-)
I also took a look at the OpenBSD 5.9 (the last that suppoted VAX) source code and they do a nice thing: if framebuffer console fails, it fallsback to serial console. In the case of NetBSD, code above and detection of SPX, LCG, etc. are totally unrelated. Would it be a good idea to refactor it so it sets up the serial console if it doesn't detect the video cards (or if the kernel is compiled with no support for it), no matter the state of S3 switch is? (Anyway, I see to be the only one with a broken S3 switch :-).
Thanks! -- Silas