summaryrefslogtreecommitdiffstats
path: root/arch/blackfin/mach-bf561/smp.c
blob: f540ed1257d6bc707cf8bc3c8a20a5f9e3e41c74 (plain)
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
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
/*
 * Copyright 2007-2009 Analog Devices Inc.
 *               Philippe Gerum <rpm@xenomai.org>
 *
 * Licensed under the GPL-2 or later.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <asm/smp.h>
#include <asm/dma.h>
#include <asm/time.h>

static DEFINE_SPINLOCK(boot_lock);

/*
 * platform_init_cpus() - Tell the world about how many cores we
 * have. This is called while setting up the architecture support
 * (setup_arch()), so don't be too demanding here with respect to
 * available kernel services.
 */

void __init platform_init_cpus(void)
{
	cpu_set(0, cpu_possible_map); /* CoreA */
	cpu_set(1, cpu_possible_map); /* CoreB */
}

void __init platform_prepare_cpus(unsigned int max_cpus)
{
	int len;

	len = &coreb_trampoline_end - &coreb_trampoline_start + 1;
	BUG_ON(len > L1_CODE_LENGTH);

	dma_memcpy((void *)COREB_L1_CODE_START, &coreb_trampoline_start, len);

	/* Both cores ought to be present on a bf561! */
	cpu_set(0, cpu_present_map); /* CoreA */
	cpu_set(1, cpu_present_map); /* CoreB */

	printk(KERN_INFO "CoreB bootstrap code to SRAM %p via DMA.\n", (void *)COREB_L1_CODE_START);
}

int __init setup_profiling_timer(unsigned int multiplier) /* not supported */
{
	return -EINVAL;
}

void __cpuinit platform_secondary_init(unsigned int cpu)
{
	/* Clone setup for peripheral interrupt sources from CoreA. */
	bfin_write_SICB_IMASK0(bfin_read_SIC_IMASK0());
	bfin_write_SICB_IMASK1(bfin_read_SIC_IMASK1());
	SSYNC();

	/* Clone setup for IARs from CoreA. */
	bfin_write_SICB_IAR0(bfin_read_SIC_IAR0());
	bfin_write_SICB_IAR1(bfin_read_SIC_IAR1());
	bfin_write_SICB_IAR2(bfin_read_SIC_IAR2());
	bfin_write_SICB_IAR3(bfin_read_SIC_IAR3());
	bfin_write_SICB_IAR4(bfin_read_SIC_IAR4());
	bfin_write_SICB_IAR5(bfin_read_SIC_IAR5());
	bfin_write_SICB_IAR6(bfin_read_SIC_IAR6());
	bfin_write_SICB_IAR7(bfin_read_SIC_IAR7());
	bfin_write_SICB_IWR0(IWR_DISABLE_ALL);
	bfin_write_SICB_IWR1(IWR_DISABLE_ALL);
	SSYNC();

	/* Store CPU-private information to the cpu_data array. */
	bfin_setup_cpudata(cpu);

	/* We are done with local CPU inits, unblock the boot CPU. */
	set_cpu_online(cpu, true);
	spin_lock(&boot_lock);
	spin_unlock(&boot_lock);
}

int __cpuinit platform_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
	unsigned long timeout;

	printk(KERN_INFO "Booting Core B.\n");

	spin_lock(&boot_lock);

	if ((bfin_read_SIC_SYSCR() & COREB_SRAM_INIT) == 0) {
		/* CoreB already running, sending ipi to wakeup it */
		platform_send_ipi_cpu(cpu, IRQ_SUPPLE_0);
	} else {
		/* Kick CoreB, which should start execution from CORE_SRAM_BASE. */
		bfin_write_SIC_SYSCR(bfin_read_SIC_SYSCR() & ~COREB_SRAM_INIT);
		SSYNC();
	}

	timeout = jiffies + 1 * HZ;
	while (time_before(jiffies, timeout)) {
		if (cpu_online(cpu))
			break;
		udelay(100);
		barrier();
	}

	if (cpu_online(cpu)) {
		/* release the lock and let coreb run */
		spin_unlock(&boot_lock);
		return 0;
	} else
		panic("CPU%u: processor failed to boot\n", cpu);
}

void __init platform_request_ipi(irq_handler_t handler)
{
	int ret;

	ret = request_irq(IRQ_SUPPLE_0, handler, IRQF_DISABLED,
			  "Supplemental Interrupt0", handler);
	if (ret)
		panic("Cannot request supplemental interrupt 0 for IPI service");
}

void platform_send_ipi(cpumask_t callmap)
{
	unsigned int cpu;

	for_each_cpu_mask(cpu, callmap) {
		BUG_ON(cpu >= 2);
		SSYNC();
		bfin_write_SICB_SYSCR(bfin_read_SICB_SYSCR() | (1 << (6 + cpu)));
		SSYNC();
	}
}

void platform_send_ipi_cpu(unsigned int cpu)
{
	BUG_ON(cpu >= 2);
	SSYNC();
	bfin_write_SICB_SYSCR(bfin_read_SICB_SYSCR() | (1 << (6 + cpu)));
	SSYNC();
}

void platform_clear_ipi(unsigned int cpu)
{
	BUG_ON(cpu >= 2);
	SSYNC();
	bfin_write_SICB_SYSCR(bfin_read_SICB_SYSCR() | (1 << (10 + cpu)));
	SSYNC();
}

/*
 * Setup core B's local core timer.
 * In SMP, core timer is used for clock event device.
 */
void __cpuinit bfin_local_timer_setup(void)
{
#if defined(CONFIG_TICKSOURCE_CORETMR)
	bfin_coretmr_init();
	bfin_coretmr_clockevent_init();
	get_irq_chip(IRQ_CORETMR)->unmask(IRQ_CORETMR);
#else
	/* Power down the core timer, just to play safe. */
	bfin_write_TCNTL(0);
#endif

}
OpenPOWER on IntegriCloud