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) 2007 MIPS Technologies, Inc. All rights reserved.
7 * Copyright (C) 2013 Imagination Technologies Ltd.
8 *
9 * Arbitrary Monitor Interface
10 */
11 #include <linux/kernel.h>
12 #include <linux/smp.h>
13
14 #include <asm/addrspace.h>
15 #include <asm/mipsmtregs.h>
16 #include <asm/mips-boards/launch.h>
17 #include <asm/vpe.h>
18
amon_cpu_avail(int cpu)19 int amon_cpu_avail(int cpu)
20 {
21 struct cpulaunch *launch = (struct cpulaunch *)CKSEG0ADDR(CPULAUNCH);
22
23 if (cpu < 0 || cpu >= NCPULAUNCH) {
24 pr_debug("avail: cpu%d is out of range\n", cpu);
25 return 0;
26 }
27
28 launch += cpu;
29 if (!(launch->flags & LAUNCH_FREADY)) {
30 pr_debug("avail: cpu%d is not ready\n", cpu);
31 return 0;
32 }
33 if (launch->flags & (LAUNCH_FGO|LAUNCH_FGONE)) {
34 pr_debug("avail: too late.. cpu%d is already gone\n", cpu);
35 return 0;
36 }
37
38 return 1;
39 }
40
amon_cpu_start(int cpu,unsigned long pc,unsigned long sp,unsigned long gp,unsigned long a0)41 int amon_cpu_start(int cpu,
42 unsigned long pc, unsigned long sp,
43 unsigned long gp, unsigned long a0)
44 {
45 volatile struct cpulaunch *launch =
46 (struct cpulaunch *)CKSEG0ADDR(CPULAUNCH);
47
48 if (!amon_cpu_avail(cpu))
49 return -1;
50 if (cpu == smp_processor_id()) {
51 pr_debug("launch: I am cpu%d!\n", cpu);
52 return -1;
53 }
54 launch += cpu;
55
56 pr_debug("launch: starting cpu%d\n", cpu);
57
58 launch->pc = pc;
59 launch->gp = gp;
60 launch->sp = sp;
61 launch->a0 = a0;
62
63 smp_wmb(); /* Target must see parameters before go */
64 launch->flags |= LAUNCH_FGO;
65 smp_wmb(); /* Target must see go before we poll */
66
67 while ((launch->flags & LAUNCH_FGONE) == 0)
68 ;
69 smp_rmb(); /* Target will be updating flags soon */
70 pr_debug("launch: cpu%d gone!\n", cpu);
71
72 return 0;
73 }
74
75 #ifdef CONFIG_MIPS_VPE_LOADER_CMP
vpe_run(struct vpe * v)76 int vpe_run(struct vpe *v)
77 {
78 struct vpe_notifications *n;
79
80 if (amon_cpu_start(aprp_cpu_index(), v->__start, 0, 0, 0) < 0)
81 return -1;
82
83 list_for_each_entry(n, &v->notify, list)
84 n->start(VPE_MODULE_MINOR);
85
86 return 0;
87 }
88 #endif
89