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authorChristian Cunningham <cc@localhost>2022-02-01 18:26:33 -0700
committerChristian Cunningham <cc@localhost>2022-02-01 18:26:33 -0700
commitc7169a96c46be8580613c67801ffb48e21231c8b (patch)
tree584b4f8ae8744113aa8c4b19a4d960b9010ce72d /src/sys
parente71ca9d94c38d61096e587e1fa17a8b79cd89397 (diff)
Preserve CPSR
Fixed syscall bug
Diffstat (limited to 'src/sys')
-rw-r--r--src/sys/schedule.S6
1 files changed, 5 insertions, 1 deletions
diff --git a/src/sys/schedule.S b/src/sys/schedule.S
index c8dcaa2..aa55ac2 100644
--- a/src/sys/schedule.S
+++ b/src/sys/schedule.S
@@ -10,9 +10,11 @@
push {lr}
ldr r3, =scheduler // struct Scheduler
ldr r2, [r3, #0] // struct Thread* rthread
- str lr, [r2, #0] // svc_lr -> void* pc
str sp, [r2, #4] // svc_lr -> void* sp
+ mrs r1, cpsr
+ str r1, [r2, #0xc] // preserve cpsr
cps #0x13 // Svc mode
+ str lr, [r2, #0] // svc_lr -> void* pc
.endm
.macro restore_ctx
@@ -20,7 +22,9 @@
ldr r2, [r3, #0] // struct Thread* rthread
ldr lr, [r2, #0] // void* pc -> lr_svc
ldr r0, [r2, #4] // void* sp -> r0
+ ldr r1, [r2, #0xc] // restore cpsr
cps #0x1f // Sys mode
+ msr cpsr, r1
mov sp, r0 // Set stack pointer
// Restore Usr regs
pop {lr}