platsmp.c
3.36 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
/*
* This file contains Xilinx specific SMP code, used to start up
* the second processor.
*
* Copyright (C) 2011-2013 Xilinx
*
* based on linux/arch/arm/mach-realview/platsmp.c
*
* Copyright (C) 2002 ARM Ltd.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/export.h>
#include <linux/jiffies.h>
#include <linux/init.h>
#include <linux/io.h>
#include <asm/cacheflush.h>
#include <asm/smp_scu.h>
#include <linux/irqchip/arm-gic.h>
#include "common.h"
/*
* Store number of cores in the system
* Because of scu_get_core_count() must be in __init section and can't
* be called from zynq_cpun_start() because it is not in __init section.
*/
static int ncores;
int zynq_cpun_start(u32 address, int cpu)
{
u32 trampoline_code_size = &zynq_secondary_trampoline_end -
&zynq_secondary_trampoline;
/* MS: Expectation that SLCR are directly map and accessible */
/* Not possible to jump to non aligned address */
if (!(address & 3) && (!address || (address >= trampoline_code_size))) {
/* Store pointer to ioremap area which points to address 0x0 */
static u8 __iomem *zero;
u32 trampoline_size = &zynq_secondary_trampoline_jump -
&zynq_secondary_trampoline;
zynq_slcr_cpu_stop(cpu);
if (address) {
if (__pa(PAGE_OFFSET)) {
zero = ioremap(0, trampoline_code_size);
if (!zero) {
pr_warn("BOOTUP jump vectors not accessible\n");
return -1;
}
} else {
zero = (__force u8 __iomem *)PAGE_OFFSET;
}
/*
* This is elegant way how to jump to any address
* 0x0: Load address at 0x8 to r0
* 0x4: Jump by mov instruction
* 0x8: Jumping address
*/
memcpy((__force void *)zero, &zynq_secondary_trampoline,
trampoline_size);
writel(address, zero + trampoline_size);
flush_cache_all();
outer_flush_range(0, trampoline_code_size);
smp_wmb();
if (__pa(PAGE_OFFSET))
iounmap(zero);
}
zynq_slcr_cpu_start(cpu);
return 0;
}
pr_warn("Can't start CPU%d: Wrong starting address %x\n", cpu, address);
return -1;
}
EXPORT_SYMBOL(zynq_cpun_start);
static int zynq_boot_secondary(unsigned int cpu,
struct task_struct *idle)
{
return zynq_cpun_start(virt_to_phys(zynq_secondary_startup), cpu);
}
/*
* Initialise the CPU possible map early - this describes the CPUs
* which may be present or become present in the system.
*/
static void __init zynq_smp_init_cpus(void)
{
int i;
ncores = scu_get_core_count(zynq_scu_base);
for (i = 0; i < ncores && i < CONFIG_NR_CPUS; i++)
set_cpu_possible(i, true);
}
static void __init zynq_smp_prepare_cpus(unsigned int max_cpus)
{
scu_enable(zynq_scu_base);
}
#ifdef CONFIG_HOTPLUG_CPU
static int zynq_cpu_kill(unsigned cpu)
{
zynq_slcr_cpu_stop(cpu);
return 1;
}
#endif
struct smp_operations zynq_smp_ops __initdata = {
.smp_init_cpus = zynq_smp_init_cpus,
.smp_prepare_cpus = zynq_smp_prepare_cpus,
.smp_boot_secondary = zynq_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_die = zynq_platform_cpu_die,
.cpu_kill = zynq_cpu_kill,
#endif
};