xref: /openbmc/linux/arch/mips/cavium-octeon/cpu.c (revision a09d2831)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2009 Wind River Systems,
7  *   written by Ralf Baechle <ralf@linux-mips.org>
8  */
9 #include <linux/init.h>
10 #include <linux/irqflags.h>
11 #include <linux/notifier.h>
12 #include <linux/prefetch.h>
13 #include <linux/sched.h>
14 
15 #include <asm/cop2.h>
16 #include <asm/current.h>
17 #include <asm/mipsregs.h>
18 #include <asm/page.h>
19 #include <asm/octeon/octeon.h>
20 
21 static int cnmips_cu2_call(struct notifier_block *nfb, unsigned long action,
22 	void *data)
23 {
24 	unsigned long flags;
25 	unsigned int status;
26 
27 	switch (action) {
28 	case CU2_EXCEPTION:
29 		prefetch(&current->thread.cp2);
30 		local_irq_save(flags);
31 		KSTK_STATUS(current) |= ST0_CU2;
32 		status = read_c0_status();
33 		write_c0_status(status | ST0_CU2);
34 		octeon_cop2_restore(&(current->thread.cp2));
35 		write_c0_status(status & ~ST0_CU2);
36 		local_irq_restore(flags);
37 
38 		return NOTIFY_BAD;	/* Don't call default notifier */
39 	}
40 
41 	return NOTIFY_OK;		/* Let default notifier send signals */
42 }
43 
44 static struct notifier_block cnmips_cu2_notifier = {
45 	.notifier_call = cnmips_cu2_call,
46 };
47 
48 static int cnmips_cu2_setup(void)
49 {
50 	return register_cu2_notifier(&cnmips_cu2_notifier);
51 }
52 early_initcall(cnmips_cu2_setup);
53