PR/60204 CVS commit: src/sys/dev/arcbios

["Adrian Chadd" <adrian%netbsd.org@localhost>]

The following reply was made to PR port-sgimips/60204; it has been noted by GNATS.

From: "Adrian Chadd" <adrian%netbsd.org@localhost>
To: gnats-bugs%gnats.NetBSD.org@localhost
Cc: 
Subject: PR/60204 CVS commit: src/sys/dev/arcbios
Date: Sun, 3 May 2026 23:06:13 +0000

 Module Name:	src
 Committed By:	adrian
 Date:		Sun May  3 23:06:13 UTC 2026
 
 Modified Files:
 	src/sys/dev/arcbios: arcbios_calls.S
 
 Log Message:
 arcbios: enable FPU around ARCS calls
 
 This seems required for the SGI O2 for PROM graphics console IO to work
 when it scrolls.  See PR port-sgimips/60204 for more details.
 
 The issue was introduced in v1.214 of sys/arch/mips/mips/locore.S .
 
 Notably maya@ disabled the FPU early in boot, expecting the rest of
 boot to run with the FPU disabled. The FPU is being explicitly
 enabled/disabled here to keep to the spirit of maya@'s above commit.
 
 A "better" solution would be to use the pcu API and mark the thread
 as needing the FPU for the duration of the arcbios call, however:
 
  * The current MIPS pcu FPU code in sys/arch/mips/mips/mips_fpu.c
    doesn't support FPU use in kernel yet; and
  * this stuff is called super early during boot and once the OS starts
    the ARCBIOS API is no longer supposed to be used.
 
 
 To generate a diff of this commit:
 cvs rdiff -u -r1.6 -r1.7 src/sys/dev/arcbios/arcbios_calls.S
 
 Please note that diffs are not public domain; they are subject to the
 copyright notices on the relevant files.