1 /*
2  * Copyright 2007-2009 Analog Devices Inc.
3  *               Philippe Gerum <rpm@xenomai.org>
4  *
5  * Licensed under the GPL-2 or later.
6  */
7 
8 #include <linux/init.h>
9 #include <linux/kernel.h>
10 #include <linux/sched.h>
11 #include <linux/delay.h>
12 #include <asm/smp.h>
13 #include <asm/dma.h>
14 #include <asm/time.h>
15 
16 static DEFINE_SPINLOCK(boot_lock);
17 
18 /*
19  * platform_init_cpus() - Tell the world about how many cores we
20  * have. This is called while setting up the architecture support
21  * (setup_arch()), so don't be too demanding here with respect to
22  * available kernel services.
23  */
24 
platform_init_cpus(void)25 void __init platform_init_cpus(void)
26 {
27 	struct cpumask mask;
28 
29 	cpumask_set_cpu(0, &mask); /* CoreA */
30 	cpumask_set_cpu(1, &mask); /* CoreB */
31 	init_cpu_possible(&mask);
32 }
33 
platform_prepare_cpus(unsigned int max_cpus)34 void __init platform_prepare_cpus(unsigned int max_cpus)
35 {
36 	struct cpumask mask;
37 
38 	bfin_relocate_coreb_l1_mem();
39 
40 	/* Both cores ought to be present on a bf561! */
41 	cpumask_set_cpu(0, &mask); /* CoreA */
42 	cpumask_set_cpu(1, &mask); /* CoreB */
43 	init_cpu_present(&mask);
44 }
45 
setup_profiling_timer(unsigned int multiplier)46 int __init setup_profiling_timer(unsigned int multiplier) /* not supported */
47 {
48 	return -EINVAL;
49 }
50 
platform_secondary_init(unsigned int cpu)51 void __cpuinit platform_secondary_init(unsigned int cpu)
52 {
53 	/* Clone setup for peripheral interrupt sources from CoreA. */
54 	bfin_write_SICB_IMASK0(bfin_read_SIC_IMASK0());
55 	bfin_write_SICB_IMASK1(bfin_read_SIC_IMASK1());
56 	SSYNC();
57 
58 	/* Clone setup for IARs from CoreA. */
59 	bfin_write_SICB_IAR0(bfin_read_SIC_IAR0());
60 	bfin_write_SICB_IAR1(bfin_read_SIC_IAR1());
61 	bfin_write_SICB_IAR2(bfin_read_SIC_IAR2());
62 	bfin_write_SICB_IAR3(bfin_read_SIC_IAR3());
63 	bfin_write_SICB_IAR4(bfin_read_SIC_IAR4());
64 	bfin_write_SICB_IAR5(bfin_read_SIC_IAR5());
65 	bfin_write_SICB_IAR6(bfin_read_SIC_IAR6());
66 	bfin_write_SICB_IAR7(bfin_read_SIC_IAR7());
67 	bfin_write_SICB_IWR0(IWR_DISABLE_ALL);
68 	bfin_write_SICB_IWR1(IWR_DISABLE_ALL);
69 	SSYNC();
70 
71 	/* We are done with local CPU inits, unblock the boot CPU. */
72 	set_cpu_online(cpu, true);
73 	spin_lock(&boot_lock);
74 	spin_unlock(&boot_lock);
75 }
76 
platform_boot_secondary(unsigned int cpu,struct task_struct * idle)77 int __cpuinit platform_boot_secondary(unsigned int cpu, struct task_struct *idle)
78 {
79 	unsigned long timeout;
80 
81 	printk(KERN_INFO "Booting Core B.\n");
82 
83 	spin_lock(&boot_lock);
84 
85 	if ((bfin_read_SYSCR() & COREB_SRAM_INIT) == 0) {
86 		/* CoreB already running, sending ipi to wakeup it */
87 		smp_send_reschedule(cpu);
88 	} else {
89 		/* Kick CoreB, which should start execution from CORE_SRAM_BASE. */
90 		bfin_write_SYSCR(bfin_read_SYSCR() & ~COREB_SRAM_INIT);
91 		SSYNC();
92 	}
93 
94 	timeout = jiffies + 1 * HZ;
95 	while (time_before(jiffies, timeout)) {
96 		if (cpu_online(cpu))
97 			break;
98 		udelay(100);
99 		barrier();
100 	}
101 
102 	if (cpu_online(cpu)) {
103 		/* release the lock and let coreb run */
104 		spin_unlock(&boot_lock);
105 		return 0;
106 	} else
107 		panic("CPU%u: processor failed to boot\n", cpu);
108 }
109 
110 static const char supple0[] = "IRQ_SUPPLE_0";
111 static const char supple1[] = "IRQ_SUPPLE_1";
platform_request_ipi(int irq,void * handler)112 void __init platform_request_ipi(int irq, void *handler)
113 {
114 	int ret;
115 	const char *name = (irq == IRQ_SUPPLE_0) ? supple0 : supple1;
116 
117 	ret = request_irq(irq, handler, IRQF_PERCPU | IRQF_NO_SUSPEND |
118 			IRQF_FORCE_RESUME, name, handler);
119 	if (ret)
120 		panic("Cannot request %s for IPI service", name);
121 }
122 
platform_send_ipi(cpumask_t callmap,int irq)123 void platform_send_ipi(cpumask_t callmap, int irq)
124 {
125 	unsigned int cpu;
126 	int offset = (irq == IRQ_SUPPLE_0) ? 6 : 8;
127 
128 	for_each_cpu_mask(cpu, callmap) {
129 		BUG_ON(cpu >= 2);
130 		SSYNC();
131 		bfin_write_SICB_SYSCR(bfin_read_SICB_SYSCR() | (1 << (offset + cpu)));
132 		SSYNC();
133 	}
134 }
135 
platform_send_ipi_cpu(unsigned int cpu,int irq)136 void platform_send_ipi_cpu(unsigned int cpu, int irq)
137 {
138 	int offset = (irq == IRQ_SUPPLE_0) ? 6 : 8;
139 	BUG_ON(cpu >= 2);
140 	SSYNC();
141 	bfin_write_SICB_SYSCR(bfin_read_SICB_SYSCR() | (1 << (offset + cpu)));
142 	SSYNC();
143 }
144 
platform_clear_ipi(unsigned int cpu,int irq)145 void platform_clear_ipi(unsigned int cpu, int irq)
146 {
147 	int offset = (irq == IRQ_SUPPLE_0) ? 10 : 12;
148 	BUG_ON(cpu >= 2);
149 	SSYNC();
150 	bfin_write_SICB_SYSCR(bfin_read_SICB_SYSCR() | (1 << (offset + cpu)));
151 	SSYNC();
152 }
153 
154 /*
155  * Setup core B's local core timer.
156  * In SMP, core timer is used for clock event device.
157  */
bfin_local_timer_setup(void)158 void __cpuinit bfin_local_timer_setup(void)
159 {
160 #if defined(CONFIG_TICKSOURCE_CORETMR)
161 	struct irq_data *data = irq_get_irq_data(IRQ_CORETMR);
162 	struct irq_chip *chip = irq_data_get_irq_chip(data);
163 
164 	bfin_coretmr_init();
165 	bfin_coretmr_clockevent_init();
166 
167 	chip->irq_unmask(data);
168 #else
169 	/* Power down the core timer, just to play safe. */
170 	bfin_write_TCNTL(0);
171 #endif
172 
173 }
174