xref: /openbmc/linux/arch/mips/cavium-octeon/cpu.c (revision d9fd5a71)
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/ptrace.h>
14 #include <linux/sched.h>
15 #include <linux/sched/task_stack.h>
16 
17 #include <asm/cop2.h>
18 #include <asm/current.h>
19 #include <asm/mipsregs.h>
20 #include <asm/page.h>
21 #include <asm/octeon/octeon.h>
22 
23 static int cnmips_cu2_call(struct notifier_block *nfb, unsigned long action,
24 	void *data)
25 {
26 	unsigned long flags;
27 	unsigned int status;
28 
29 	switch (action) {
30 	case CU2_EXCEPTION:
31 		prefetch(&current->thread.cp2);
32 		local_irq_save(flags);
33 		KSTK_STATUS(current) |= ST0_CU2;
34 		status = read_c0_status();
35 		write_c0_status(status | ST0_CU2);
36 		octeon_cop2_restore(&(current->thread.cp2));
37 		write_c0_status(status & ~ST0_CU2);
38 		local_irq_restore(flags);
39 
40 		return NOTIFY_BAD;	/* Don't call default notifier */
41 	}
42 
43 	return NOTIFY_OK;		/* Let default notifier send signals */
44 }
45 
46 static int __init cnmips_cu2_setup(void)
47 {
48 	return cu2_notifier(cnmips_cu2_call, 0);
49 }
50 early_initcall(cnmips_cu2_setup);
51