patch-2.4.19 linux-2.4.19/arch/mips/sibyte/sb1/cache_err_handler.S

• Lines: 88
• Date: Fri Aug 2 17:39:43 2002
• Orig file: linux-2.4.18/arch/mips/sibyte/sb1/cache_err_handler.S
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.18/arch/mips/sibyte/sb1/cache_err_handler.S linux-2.4.19/arch/mips/sibyte/sb1/cache_err_handler.S
@@ -0,0 +1,87 @@
+/*
+ * Copyright (C) 2001 Broadcom Corporation
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+#include <linux/config.h>
+
+#include <asm/asm.h>
+#include <asm/regdef.h>
+#include <asm/mipsregs.h>
+
+	.text
+	/* Special Cache Error handler for SB1 for now */
+	LEAF(except_vec2_sb1)
+	.set	noat
+	.set	mips0
+	/*
+	 * This is a very bad place to be.  Our cache error detection has
+	 * triggered.  If we have write-back data in the cache, we may not be
+	 * able to recover.  As a first-order desperate measure, turn off KSEG0
+	 * cacheing.
+	 */
+	.set	push
+	#.set	mips64
+	.set	mips4
+	.set	reorder
+	# look for signature of spurious CErr
+	mfc0	k1, $26				# mfc0	k1, $26, 0
+	# check if error was recoverable
+	# XXXKW - count them
+	bltz	k1, leave_cerr
+	 nop
+
+#ifdef CONFIG_SB1_PASS_1_WORKAROUNDS
+	# look for signature of spurious CErr
+	lui	k0, 0x4000
+	bne	k0, k1, real_cerr
+	.word	0x401Bd801			# mfc0	k1, $27, 1
+	lui	k0, 0xffe0
+	and	k1, k0, k1
+	lui	k0, 0x0200
+	bne	k0, k1, real_cerr
+	 nop
+#else
+	j	real_cerr
+	 nop
+#endif
+	# XXXKW - count spurious errors
+leave_cerr:
+	# clear/unlock the registers
+	mtc0	zero, $26			# mtc0	zero, $26, 0
+	mtc0	zero, $27			# mtc0	zero, $27, 0
+	.word	0x4080d801			# mtc0	zero, $27, 1
+	.word	0x4080d803			# mtc0	zero, $27, 3
+	eret
+
+real_cerr:
+	mfc0	k0, CP0_CONFIG
+	li	k1, ~CONF_CM_CMASK
+	and	k0, k0, k1
+	ori	k0, k0, CONF_CM_UNCACHED
+	mtc0	k0, CP0_CONFIG
+	/* Give it a few cycles to sink in... */
+	sll     zero, zero, 0x1			# ssnop
+	sll     zero, zero, 0x1			# ssnop
+	sll     zero, zero, 0x1			# ssnop
+	sll     zero, zero, 0x1			# ssnop
+	sll     zero, zero, 0x1			# ssnop
+	sll     zero, zero, 0x1			# ssnop
+
+	j	sb1_cache_error
+	 nop
+
+	.set	pop
+	END(except_vec2_sb1)