diff options
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/arch/m88k/m88k/m88k_machdep.c | 35 |
1 files changed, 18 insertions, 17 deletions
diff --git a/sys/arch/m88k/m88k/m88k_machdep.c b/sys/arch/m88k/m88k/m88k_machdep.c index b542af649f6..eb7735a6e6d 100644 --- a/sys/arch/m88k/m88k/m88k_machdep.c +++ b/sys/arch/m88k/m88k/m88k_machdep.c @@ -1,4 +1,4 @@ -/* $OpenBSD: m88k_machdep.c,v 1.36 2007/12/02 21:23:18 miod Exp $ */ +/* $OpenBSD: m88k_machdep.c,v 1.37 2007/12/04 05:39:42 miod Exp $ */ /* * Copyright (c) 1998, 1999, 2000, 2001 Steve Murphree, Jr. * Copyright (c) 1996 Nivas Madhur @@ -154,37 +154,38 @@ setregs(p, pack, stack, retval) /* * We want to start executing at pack->ep_entry. The way to * do this is force the processor to fetch from ep_entry. + * * However, since we will return throug m{88100,88110}_syscall(), * we need to setup registers so that the success return, when * ``incrementing'' the instruction pointers, will cause the * binary to start at the expected address. + * + * This relies on the fact that binaries start with + * + * br.n 1f + * or r2, r0, r30 + * 1: + * + * So the first two instructions can be skipped. */ #ifdef M88110 if (CPU_IS88110) { /* - * Delay slot in exip, so we'll start at enip + 4. - * This relies on the fact that binaries start with - * - * br.n 1f - * first instruction - * 1: second instruction - * - * So by pretending exip is a delay slot, m88110_syscall() - * will resume at enip + 4... which really is the first - * instruction we want to run. + * m88110_syscall() will resume at exip + 8... which + * really is the first instruction we want to run. */ - tf->tf_exip = (pack->ep_entry & XIP_ADDR) | 1; - tf->tf_enip = pack->ep_entry & XIP_ADDR; + tf->tf_exip = pack->ep_entry & XIP_ADDR; } #endif #ifdef M88100 if (CPU_IS88100) { - /* we'll start at sfip / sfip + 4 */ - tf->tf_snip = pack->ep_entry & NIP_ADDR; - tf->tf_sfip = (pack->ep_entry & FIP_ADDR) | FIP_V; + /* + * m88100_syscall() will resume at sfip / sfip + 4. + */ + tf->tf_sfip = ((pack->ep_entry + 8) & FIP_ADDR) | FIP_V; } #endif - tf->tf_r[2] = stack; + tf->tf_r[2] = retval[0] = stack; tf->tf_r[31] = stack; retval[1] = 0; } |