/* entry.S: FR-V entry
*
* Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*
* Entry to the kernel is "interesting":
* (1) There are no stack pointers, not even for the kernel
* (2) General Registers should not be clobbered
* (3) There are no kernel-only data registers
* (4) Since all addressing modes are wrt to a General Register, no global
* variables can be reached
*
* We deal with this by declaring that we shall kill GR28 on entering the
* kernel from userspace
*
* However, since break interrupts can interrupt the CPU even when PSR.ET==0,
* they can't rely on GR28 to be anything useful, and so need to clobber a
* separate register (GR31). Break interrupts are managed in break.S
*
* GR29 _is_ saved, and holds the current task pointer globally
*
*/
#include <linux/linkage.h>
#include <asm/thread_info.h>
#include <asm/setup.h>
#include <asm/segment.h>
#include <asm/ptrace.h>
#include <asm/errno.h>
#include <asm/cache.h>
#include <asm/spr-regs.h>
#define nr_syscalls ((syscall_table_size)/4)
.section .text.entry
.balign 4
.macro LEDS val
# sethi.p %hi(0xe1200004),gr30
# setlo %lo(0xe1200004),gr30
# setlos #~\val,gr31
# st gr31,@(gr30,gr0)
# sethi.p %hi(0xffc00100),gr30
# setlo %lo(0xffc00100),gr30
# sth gr0,@(gr30,gr0)
# membar
.endm
.macro LEDS32
# not gr31,gr31
# sethi.p %hi(0xe1200004),gr30
# setlo %lo(0xe1200004),gr30
# st.p gr31,@(gr30,gr0)
# srli gr31,#16,gr31
# sethi.p %hi(0xffc00100),gr30
# setlo %lo(0xffc00100),gr30
# sth gr31,@(gr30,gr0)
# membar
.endm
##
