blob: 469d9b0cee6dd16f80d402d5cce6ae73d8ca245e [file] [log] [blame]
Ralf Baechle39b8d522008-04-28 17:14:26 +01001/*
2 * Copyright (C) 2007 MIPS Technologies, Inc.
3 * All rights reserved.
4
5 * This program is free software; you can distribute it and/or modify it
6 * under the terms of the GNU General Public License (Version 2) as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
17 *
18 * Arbitrary Monitor interface
19 */
20
21#include <linux/kernel.h>
22#include <linux/init.h>
23#include <linux/smp.h>
24
David Daney9e867862008-09-20 10:16:36 -070025#include <asm/addrspace.h>
26#include <asm/mips-boards/launch.h>
27#include <asm/mipsmtregs.h>
Ralf Baechle39b8d522008-04-28 17:14:26 +010028
29int amon_cpu_avail(int cpu)
30{
Thomas Bogendoerfer938b2b12008-05-29 22:05:07 +020031 struct cpulaunch *launch = (struct cpulaunch *)CKSEG0ADDR(CPULAUNCH);
Ralf Baechle39b8d522008-04-28 17:14:26 +010032
33 if (cpu < 0 || cpu >= NCPULAUNCH) {
34 pr_debug("avail: cpu%d is out of range\n", cpu);
35 return 0;
36 }
37
38 launch += cpu;
39 if (!(launch->flags & LAUNCH_FREADY)) {
40 pr_debug("avail: cpu%d is not ready\n", cpu);
41 return 0;
42 }
43 if (launch->flags & (LAUNCH_FGO|LAUNCH_FGONE)) {
44 pr_debug("avail: too late.. cpu%d is already gone\n", cpu);
45 return 0;
46 }
47
48 return 1;
49}
50
51void amon_cpu_start(int cpu,
52 unsigned long pc, unsigned long sp,
53 unsigned long gp, unsigned long a0)
54{
55 volatile struct cpulaunch *launch =
Thomas Bogendoerfer938b2b12008-05-29 22:05:07 +020056 (struct cpulaunch *)CKSEG0ADDR(CPULAUNCH);
Ralf Baechle39b8d522008-04-28 17:14:26 +010057
58 if (!amon_cpu_avail(cpu))
59 return;
60 if (cpu == smp_processor_id()) {
61 pr_debug("launch: I am cpu%d!\n", cpu);
62 return;
63 }
64 launch += cpu;
65
66 pr_debug("launch: starting cpu%d\n", cpu);
67
68 launch->pc = pc;
69 launch->gp = gp;
70 launch->sp = sp;
71 launch->a0 = a0;
72
Chris Dearman2ee0a422009-07-10 02:06:38 -070073 smp_wmb(); /* Target must see parameters before go */
Ralf Baechle39b8d522008-04-28 17:14:26 +010074 launch->flags |= LAUNCH_FGO;
Chris Dearman2ee0a422009-07-10 02:06:38 -070075 smp_wmb(); /* Target must see go before we poll */
76
Ralf Baechle39b8d522008-04-28 17:14:26 +010077 while ((launch->flags & LAUNCH_FGONE) == 0)
78 ;
Chris Dearman2ee0a422009-07-10 02:06:38 -070079 smp_rmb(); /* Target will be updating flags soon */
Ralf Baechle39b8d522008-04-28 17:14:26 +010080 pr_debug("launch: cpu%d gone!\n", cpu);
81}