/*
* File: arch/blackfin/mach-common/entry.S
* Based on:
* Author: Linus Torvalds
*
* Created: ?
* Description: contains the system-call and fault low-level handling routines.
* This also contains the timer-interrupt handler, as well as all
* interrupts and faults that can result in a task-switch.
*
* Modified:
* Copyright 2004-2006 Analog Devices Inc.
*
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see the file COPYING, or write
* to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/* NOTE: This code handles signal-recognition, which happens every time
* after a timer-interrupt and after each system call.
*/
#include <linux/init.h>
#include <linux/linkage.h>
#include <linux/unistd.h>
#include <asm/blackfin.h>
#include <asm/errno.h>
#include <asm/thread_info.h> /* TIF_NEED_RESCHED */
#include <asm/asm-offsets.h>
#include <asm/trace.h>
#include <asm/mach-common/context.S>
#if defined(CONFIG_BFIN_SCRATCH_REG_RETN)
# define EX_SCRATCH_REG RETN
#elif defined(CONFIG_BFIN_SCRATCH_REG_RETE)
# define EX_SCRATCH_REG RETE
#else
# define EX_SCRATCH_REG CYCLES
#endif
#if ANOMALY_05000281
ENTRY(_safe_speculative_execution)
NOP;
NOP;
NOP;
jump _safe_speculative_execution;
ENDPROC(_safe_speculative_execution)
#endif
#ifdef CONFIG_EXCPT_IRQ_SYSC_L1
.section .l1.text
#else
.text
#endif
/* Slightly simplified and streamlined entry point for CPLB misses.
* This one does not lower the level to IRQ5, and thus can be used to
* patch up CPLB misses on the kernel stack.
*/
#if ANOMALY_05000261
#define _ex_dviol _ex_workaround_261
#define _ex_dmiss _ex_workaround_261
#define _ex_dmult _ex_workaround_261
ENTRY(_ex_workaround_261)
/*
* Work around an anomaly: if we see a new DCPLB fault, return
* without doing anything. Then, if we get the same fault again,
* handle it.
*/
P4 = R7; /* Store EXCAUSE */
p5.l = _last_cplb_fault_retx;
p5.h = _last_cplb_fault_retx;
r7 = [p5];
r6 = retx;
[p5] = r6;
cc = r6 == r7;
if !cc jump _bfin_return_from_exception;
/* fall through */
R7 = P4;
R6 = 0x26; /* Data CPLB Miss */
cc = R6 == R7;
if cc jump _ex_dcplb_miss
