From 1dd22722f6bf9be9821657a2d59fae4d4365fb32 Mon Sep 17 00:00:00 2001 From: Magnus Damm Date: Mon, 23 Feb 2009 07:15:07 +0000 Subject: [PATCH] sh: rework register restore code for sh3/sh4/sh4a This patch reworks the sh3/sh4/sh4a register restore code in the following ways: - break out restore_regs() from restore_all() - the register saving order is unchanged - use restore_regs() in sh_bios_handler and restore_all - document the function Signed-off-by: Magnus Damm Signed-off-by: Paul Mundt --- arch/sh/kernel/cpu/sh3/entry.S | 68 +++++++++++++++++----------------- 1 file changed, 33 insertions(+), 35 deletions(-) diff --git a/arch/sh/kernel/cpu/sh3/entry.S b/arch/sh/kernel/cpu/sh3/entry.S index f3db143e70b2..cbffbffce351 100644 --- a/arch/sh/kernel/cpu/sh3/entry.S +++ b/arch/sh/kernel/cpu/sh3/entry.S @@ -188,44 +188,35 @@ call_dae: #if defined(CONFIG_SH_STANDARD_BIOS) /* Unwind the stack and jmp to the debug entry */ ENTRY(sh_bios_handler) - mov.l @r15+, r0 - mov.l @r15+, r1 - mov.l @r15+, r2 - mov.l @r15+, r3 - mov.l @r15+, r4 - mov.l @r15+, r5 - mov.l @r15+, r6 - mov.l @r15+, r7 - stc sr, r8 - mov.l 1f, r9 ! BL =1, RB=1, IMASK=0x0F - or r9, r8 - ldc r8, sr ! here, change the register bank - mov.l @r15+, r8 - mov.l @r15+, r9 - mov.l @r15+, r10 - mov.l @r15+, r11 - mov.l @r15+, r12 - mov.l @r15+, r13 - mov.l @r15+, r14 - mov.l @r15+, k0 - ldc.l @r15+, spc - lds.l @r15+, pr - mov.l @r15+, k1 - ldc.l @r15+, gbr - lds.l @r15+, mach - lds.l @r15+, macl - mov k0, r15 + mov.l 1f, r8 + bsr restore_regs + nop + + lds k2, pr ! restore pr + mov k4, r15 ! mov.l 2f, k0 mov.l @k0, k0 jmp @k0 - ldc k1, ssr + ldc k3, ssr .align 2 1: .long 0x300000f0 2: .long gdb_vbr_vector #endif /* CONFIG_SH_STANDARD_BIOS */ -restore_all: +! restore_regs() +! - restore r0, r1, r2, r3, r4, r5, r6, r7 from the stack +! - switch bank +! - restore r8, r9, r10, r11, r12, r13, r14, r15 from the stack +! - restore spc, pr*, ssr, gbr, mach, macl, skip default tra +! k2 returns original pr +! k3 returns original sr +! k4 returns original stack pointer +! r8 passes SR bitmask, overwritten with restored data on return +! r9 trashed +! BL=0 on entry, on exit BL=1 (depending on r8). + +restore_regs: mov.l @r15+, r0 mov.l @r15+, r1 mov.l @r15+, r2 @@ -235,10 +226,9 @@ restore_all: mov.l @r15+, r6 mov.l @r15+, r7 ! - stc sr, r8 - mov.l 7f, r9 - or r9, r8 ! BL =1, RB=1 - ldc r8, sr ! here, change the register bank + stc sr, r9 + or r8, r9 + ldc r9, sr ! mov.l @r15+, r8 mov.l @r15+, r9 @@ -249,12 +239,20 @@ restore_all: mov.l @r15+, r14 mov.l @r15+, k4 ! original stack pointer ldc.l @r15+, spc - lds.l @r15+, pr + mov.l @r15+, k2 ! original PR mov.l @r15+, k3 ! original SR ldc.l @r15+, gbr lds.l @r15+, mach lds.l @r15+, macl - add #4, r15 ! Skip syscall number + rts + add #4, r15 ! Skip syscall number + +restore_all: + mov.l 7f, r8 + bsr restore_regs + nop + + lds k2, pr ! restore pr ! #ifdef CONFIG_SH_DSP mov.l @r15+, k0 ! DSP mode marker -- 2.20.1