aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--arch/arm/mach-omap2/omap-headsmp.S46
-rw-r--r--arch/arm/mach-omap2/omap-smp.c178
-rw-r--r--arch/arm/plat-omap/include/mach/smp.h51
3 files changed, 275 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/omap-headsmp.S b/arch/arm/mach-omap2/omap-headsmp.S
new file mode 100644
index 000000000000..4afadba09477
--- /dev/null
+++ b/arch/arm/mach-omap2/omap-headsmp.S
@@ -0,0 +1,46 @@
1/*
2 * Secondary CPU startup routine source file.
3 *
4 * Copyright (C) 2009 Texas Instruments, Inc.
5 *
6 * Author:
7 * Santosh Shilimkar <santosh.shilimkar@ti.com>
8 *
9 * Interface functions needed for the SMP. This file is based on arm
10 * realview smp platform.
11 * Copyright (c) 2003 ARM Limited.
12 *
13 * This program is free software,you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License version 2 as
15 * published by the Free Software Foundation.
16 */
17
18#include <linux/linkage.h>
19#include <linux/init.h>
20
21/* Physical address needed since MMU not enabled yet on secondary core */
22#define OMAP4_AUX_CORE_BOOT1_PA 0x48281804
23
24 __INIT
25
26/*
27 * OMAP4 specific entry point for secondary CPU to jump from ROM
28 * code. This routine also provides a holding flag into which
29 * secondary core is held until we're ready for it to initialise.
30 * The primary core will update the this flag using a hardware
31 * register AuxCoreBoot1.
32 */
33ENTRY(omap_secondary_startup)
34 mrc p15, 0, r0, c0, c0, 5
35 and r0, r0, #0x0f
36hold: ldr r1, =OMAP4_AUX_CORE_BOOT1_PA @ read from AuxCoreBoot1
37 ldr r2, [r1]
38 cmp r2, r0
39 bne hold
40
41 /*
42 * we've been released from the cpu_release,secondary_stack
43 * should now contain the SVC stack for this core
44 */
45 b secondary_startup
46
diff --git a/arch/arm/mach-omap2/omap-smp.c b/arch/arm/mach-omap2/omap-smp.c
new file mode 100644
index 000000000000..8fe8d230f21b
--- /dev/null
+++ b/arch/arm/mach-omap2/omap-smp.c
@@ -0,0 +1,178 @@
1/*
2 * OMAP4 SMP source file. It contains platform specific fucntions
3 * needed for the linux smp kernel.
4 *
5 * Copyright (C) 2009 Texas Instruments, Inc.
6 *
7 * Author:
8 * Santosh Shilimkar <santosh.shilimkar@ti.com>
9 *
10 * Platform file needed for the OMAP4 SMP. This file is based on arm
11 * realview smp platform.
12 * * Copyright (c) 2002 ARM Limited.
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License version 2 as
16 * published by the Free Software Foundation.
17 */
18#include <linux/init.h>
19#include <linux/device.h>
20#include <linux/jiffies.h>
21#include <linux/smp.h>
22#include <linux/io.h>
23
24#include <asm/localtimer.h>
25#include <asm/smp_scu.h>
26#include <mach/hardware.h>
27
28/* Registers used for communicating startup information */
29#define OMAP4_AUXCOREBOOT_REG0 (OMAP44XX_VA_WKUPGEN_BASE + 0x800)
30#define OMAP4_AUXCOREBOOT_REG1 (OMAP44XX_VA_WKUPGEN_BASE + 0x804)
31
32/* SCU base address */
33static void __iomem *scu_base = OMAP44XX_VA_SCU_BASE;
34
35/*
36 * Use SCU config register to count number of cores
37 */
38static inline unsigned int get_core_count(void)
39{
40 if (scu_base)
41 return scu_get_core_count(scu_base);
42 return 1;
43}
44
45static DEFINE_SPINLOCK(boot_lock);
46
47void __cpuinit platform_secondary_init(unsigned int cpu)
48{
49 trace_hardirqs_off();
50
51 /*
52 * If any interrupts are already enabled for the primary
53 * core (e.g. timer irq), then they will not have been enabled
54 * for us: do so
55 */
56
57 gic_cpu_init(0, IO_ADDRESS(OMAP44XX_GIC_CPU_BASE));
58
59 /*
60 * Synchronise with the boot thread.
61 */
62 spin_lock(&boot_lock);
63 spin_unlock(&boot_lock);
64}
65
66int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
67{
68 unsigned long timeout;
69
70 /*
71 * Set synchronisation state between this boot processor
72 * and the secondary one
73 */
74 spin_lock(&boot_lock);
75
76 /*
77 * Update the AuxCoreBoot1 with boot state for secondary core.
78 * omap_secondary_startup() routine will hold the secondary core till
79 * the AuxCoreBoot1 register is updated with cpu state
80 * A barrier is added to ensure that write buffer is drained
81 */
82 __raw_writel(cpu, OMAP4_AUXCOREBOOT_REG1);
83 smp_wmb();
84
85 timeout = jiffies + (1 * HZ);
86 while (time_before(jiffies, timeout))
87 ;
88
89 /*
90 * Now the secondary core is starting up let it run its
91 * calibrations, then wait for it to finish
92 */
93 spin_unlock(&boot_lock);
94
95 return 0;
96}
97
98static void __init wakeup_secondary(void)
99{
100 /*
101 * Write the address of secondary startup routine into the
102 * AuxCoreBoot0 where ROM code will jump and start executing
103 * on secondary core once out of WFE
104 * A barrier is added to ensure that write buffer is drained
105 */
106 __raw_writel(virt_to_phys(omap_secondary_startup), \
107 OMAP4_AUXCOREBOOT_REG0);
108 smp_wmb();
109
110 /*
111 * Send a 'sev' to wake the secondary core from WFE.
112 */
113 set_event();
114 mb();
115}
116
117/*
118 * Initialise the CPU possible map early - this describes the CPUs
119 * which may be present or become present in the system.
120 */
121void __init smp_init_cpus(void)
122{
123 unsigned int i, ncores = get_core_count();
124
125 for (i = 0; i < ncores; i++)
126 set_cpu_possible(i, true);
127}
128
129void __init smp_prepare_cpus(unsigned int max_cpus)
130{
131 unsigned int ncores = get_core_count();
132 unsigned int cpu = smp_processor_id();
133 int i;
134
135 /* sanity check */
136 if (ncores == 0) {
137 printk(KERN_ERR
138 "OMAP4: strange core count of 0? Default to 1\n");
139 ncores = 1;
140 }
141
142 if (ncores > NR_CPUS) {
143 printk(KERN_WARNING
144 "OMAP4: no. of cores (%d) greater than configured "
145 "maximum of %d - clipping\n",
146 ncores, NR_CPUS);
147 ncores = NR_CPUS;
148 }
149 smp_store_cpu_info(cpu);
150
151 /*
152 * are we trying to boot more cores than exist?
153 */
154 if (max_cpus > ncores)
155 max_cpus = ncores;
156
157 /*
158 * Initialise the present map, which describes the set of CPUs
159 * actually populated at the present time.
160 */
161 for (i = 0; i < max_cpus; i++)
162 set_cpu_present(i, true);
163
164 if (max_cpus > 1) {
165 /*
166 * Enable the local timer or broadcast device for the
167 * boot CPU, but only if we have more than one CPU.
168 */
169 percpu_timer_setup();
170
171 /*
172 * Initialise the SCU and wake up the secondary core using
173 * wakeup_secondary().
174 */
175 scu_enable(scu_base);
176 wakeup_secondary();
177 }
178}
diff --git a/arch/arm/plat-omap/include/mach/smp.h b/arch/arm/plat-omap/include/mach/smp.h
new file mode 100644
index 000000000000..dcaa8fde7063
--- /dev/null
+++ b/arch/arm/plat-omap/include/mach/smp.h
@@ -0,0 +1,51 @@
1/*
2 * OMAP4 machine specific smp.h
3 *
4 * Copyright (C) 2009 Texas Instruments, Inc.
5 *
6 * Author:
7 * Santosh Shilimkar <santosh.shilimkar@ti.com>
8 *
9 * Interface functions needed for the SMP. This file is based on arm
10 * realview smp platform.
11 * Copyright (c) 2003 ARM Limited.
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License version 2 as
15 * published by the Free Software Foundation.
16 */
17#ifndef OMAP_ARCH_SMP_H
18#define OMAP_ARCH_SMP_H
19
20#include <asm/hardware/gic.h>
21
22/*
23 * set_event() is used to wake up secondary core from wfe using sev. ROM
24 * code puts the second core into wfe(standby).
25 *
26 */
27#define set_event() __asm__ __volatile__ ("sev" : : : "memory")
28
29/* Needed for secondary core boot */
30extern void omap_secondary_startup(void);
31
32/*
33 * We use Soft IRQ1 as the IPI
34 */
35static inline void smp_cross_call(const struct cpumask *mask)
36{
37 gic_raise_softirq(mask, 1);
38}
39
40/*
41 * Read MPIDR: Multiprocessor affinity register
42 */
43#define hard_smp_processor_id() \
44 ({ \
45 unsigned int cpunum; \
46 __asm__("mrc p15, 0, %0, c0, c0, 5" \
47 : "=r" (cpunum)); \
48 cpunum &= 0x0F; \
49 })
50
51#endif
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-29 02:12:10 -0500