xref: /OK3568_Linux_fs/kernel/arch/mips/cavium-octeon/cpu.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * This file is subject to the terms and conditions of the GNU General Public
3*4882a593Smuzhiyun  * License.  See the file "COPYING" in the main directory of this archive
4*4882a593Smuzhiyun  * for more details.
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * Copyright (C) 2009 Wind River Systems,
7*4882a593Smuzhiyun  *   written by Ralf Baechle <ralf@linux-mips.org>
8*4882a593Smuzhiyun  */
9*4882a593Smuzhiyun #include <linux/init.h>
10*4882a593Smuzhiyun #include <linux/irqflags.h>
11*4882a593Smuzhiyun #include <linux/notifier.h>
12*4882a593Smuzhiyun #include <linux/prefetch.h>
13*4882a593Smuzhiyun #include <linux/ptrace.h>
14*4882a593Smuzhiyun #include <linux/sched.h>
15*4882a593Smuzhiyun #include <linux/sched/task_stack.h>
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun #include <asm/cop2.h>
18*4882a593Smuzhiyun #include <asm/current.h>
19*4882a593Smuzhiyun #include <asm/mipsregs.h>
20*4882a593Smuzhiyun #include <asm/page.h>
21*4882a593Smuzhiyun #include <asm/octeon/octeon.h>
22*4882a593Smuzhiyun 
cnmips_cu2_call(struct notifier_block * nfb,unsigned long action,void * data)23*4882a593Smuzhiyun static int cnmips_cu2_call(struct notifier_block *nfb, unsigned long action,
24*4882a593Smuzhiyun 	void *data)
25*4882a593Smuzhiyun {
26*4882a593Smuzhiyun 	unsigned long flags;
27*4882a593Smuzhiyun 	unsigned int status;
28*4882a593Smuzhiyun 
29*4882a593Smuzhiyun 	switch (action) {
30*4882a593Smuzhiyun 	case CU2_EXCEPTION:
31*4882a593Smuzhiyun 		prefetch(&current->thread.cp2);
32*4882a593Smuzhiyun 		local_irq_save(flags);
33*4882a593Smuzhiyun 		KSTK_STATUS(current) |= ST0_CU2;
34*4882a593Smuzhiyun 		status = read_c0_status();
35*4882a593Smuzhiyun 		write_c0_status(status | ST0_CU2);
36*4882a593Smuzhiyun 		octeon_cop2_restore(&(current->thread.cp2));
37*4882a593Smuzhiyun 		write_c0_status(status & ~ST0_CU2);
38*4882a593Smuzhiyun 		local_irq_restore(flags);
39*4882a593Smuzhiyun 
40*4882a593Smuzhiyun 		return NOTIFY_BAD;	/* Don't call default notifier */
41*4882a593Smuzhiyun 	}
42*4882a593Smuzhiyun 
43*4882a593Smuzhiyun 	return NOTIFY_OK;		/* Let default notifier send signals */
44*4882a593Smuzhiyun }
45*4882a593Smuzhiyun 
cnmips_cu2_setup(void)46*4882a593Smuzhiyun static int __init cnmips_cu2_setup(void)
47*4882a593Smuzhiyun {
48*4882a593Smuzhiyun 	return cu2_notifier(cnmips_cu2_call, 0);
49*4882a593Smuzhiyun }
50*4882a593Smuzhiyun early_initcall(cnmips_cu2_setup);
51