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| author | Andrew Waterman <waterman@cs.berkeley.edu> | 2014-10-31 22:40:06 -0700 |
|---|---|---|
| committer | Andrew Waterman <waterman@cs.berkeley.edu> | 2014-10-31 22:40:06 -0700 |
| commit | 069bdd3f0d1348e079221d62bdc1bd2f1bc33841 (patch) | |
| tree | a18c2dba9d724197dfb18d9faee474c350fc1b87 /pk/entry.S | |
| parent | 514adef4868460944738f39734f282dc14e4d744 (diff) | |
| download | riscv-pk-069bdd3f0d1348e079221d62bdc1bd2f1bc33841.zip riscv-pk-069bdd3f0d1348e079221d62bdc1bd2f1bc33841.tar.gz riscv-pk-069bdd3f0d1348e079221d62bdc1bd2f1bc33841.tar.bz2 | |
Implement draft of new calling convention
Here is the new syscall ABI:
syscall number in a7
args in a0 - a6
return value in a0
Here is the integer register map:
x0 -> x0
x1 -> ra
x2 -> sp
x3 -> tp
x4 -> gp
x5 -> t0
x6 -> t1
x7 -> t2
x8 -> s0
x9 -> s1
x10 -> a0
x11 -> a1
x12 -> a2
x13 -> a3
x14 -> a4
x15 -> a5
x16 -> a6
x17 -> a7
x18 -> s2
x19 -> s3
x20 -> s4
x21 -> s5
x22 -> s6
x23 -> s7
x24 -> s8
x25 -> s9
x26 -> s10
x27 -> s11
x28 -> t3
x29 -> t4
x30 -> t5
x31 -> t6
Diffstat (limited to 'pk/entry.S')
| -rw-r--r-- | pk/entry.S | 9 |
1 files changed, 4 insertions, 5 deletions
@@ -117,18 +117,17 @@ pop_tf: # write the trap frame onto the stack .global trap_entry trap_entry: csrw sup0, x1 - csrw sup1, x2 + csrw sup1, sp # when coming from kernel, continue below its stack csrr x1, status and x1, x1, SR_PS - add x2, sp, -320 + add sp, sp, -320 bnez x1, 1f - la x2, stack_top-320 + la sp, stack_top-320 1:save_tf - move sp,x2 - move a0,x2 + move a0,sp j handle_trap .bss |