From 1a4b739bbb4f8857d1b4feb46d6b3ec72269c111 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 30 Apr 2019 12:39:03 +0000 Subject: powerpc/32: implement fast entry for syscalls on BOOKE This patch implements a fast entry for syscalls. Syscalls don't have to preserve non volatile registers except LR. This patch then implement a fast entry for syscalls, where volatile registers get clobbered. As this entry is dedicated to syscall it always sets MSR_EE and warns in case MSR_EE was previously off It also assumes that the call is always from user, system calls are unexpected from kernel. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/head_44x.S | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'arch/powerpc/kernel/head_44x.S') diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S index 0381fdb294a6..f15fba58c744 100644 --- a/arch/powerpc/kernel/head_44x.S +++ b/arch/powerpc/kernel/head_44x.S @@ -285,8 +285,7 @@ interrupt_base: #endif /* System Call Interrupt */ START_EXCEPTION(SystemCall) - NORMAL_EXCEPTION_PROLOG(BOOKE_INTERRUPT_SYSCALL) - EXC_XFER_SYS(0x0c00, DoSyscall) + SYSCALL_ENTRY 0xc00 BOOKE_INTERRUPT_SYSCALL /* Auxiliary Processor Unavailable Interrupt */ EXCEPTION(0x2020, BOOKE_INTERRUPT_AP_UNAVAIL, \ -- cgit v1.2.3