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authorArnd Bergmann <arnd@arndb.de>2012-05-14 09:59:18 -0400
committerArnd Bergmann <arnd@arndb.de>2012-05-14 11:35:50 -0400
commit090a80cba39f2763a488b6f7c65e38922d5aa17a (patch)
treeba3797eeca74c42be95bc592ed2db1be99e329d2 /arch/arm/mach-spear13xx/platsmp.c
parent36be50515fe2aef61533b516fa2576a2c7fe7664 (diff)
parenteb3f995d7e73fd78b8fcdc55cfbf01a74a09a6e8 (diff)
Merge branch 'spear/13xx' into next/soc2
* spear/13xx: pinctrl: SPEAr1310: Fix pin numbers for clcd_high_res SPEAr: Update MAINTAINERS and Documentation SPEAr13xx: Add defconfig SPEAr13xx: Add compilation support SPEAr13xx: Add dts and dtsi files pinctrl: Add SPEAr13xx pinctrl drivers pinctrl: SPEAr: Create macro for declaring GPIO PINS SPEAr13xx: Add common clock framework support SPEAr13xx: Add source files SPEAr13xx: Add header files Depends on clock, pinctrl and dt branches to go first. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/arm/mach-spear13xx/platsmp.c')
-rw-r--r--arch/arm/mach-spear13xx/platsmp.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/arch/arm/mach-spear13xx/platsmp.c b/arch/arm/mach-spear13xx/platsmp.c
new file mode 100644
index 000000000000..f5d07f2663d7
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+++ b/arch/arm/mach-spear13xx/platsmp.c
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1/*
2 * arch/arm/mach-spear13xx/platsmp.c
3 *
4 * based upon linux/arch/arm/mach-realview/platsmp.c
5 *
6 * Copyright (C) 2012 ST Microelectronics Ltd.
7 * Shiraz Hashim <shiraz.hashim@st.com>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13
14#include <linux/delay.h>
15#include <linux/jiffies.h>
16#include <linux/io.h>
17#include <linux/smp.h>
18#include <asm/cacheflush.h>
19#include <asm/hardware/gic.h>
20#include <asm/smp_scu.h>
21#include <mach/spear.h>
22
23/*
24 * control for which core is the next to come out of the secondary
25 * boot "holding pen"
26 */
27volatile int __cpuinitdata pen_release = -1;
28static DEFINE_SPINLOCK(boot_lock);
29
30static void __iomem *scu_base = IOMEM(VA_SCU_BASE);
31extern void spear13xx_secondary_startup(void);
32
33void __cpuinit platform_secondary_init(unsigned int cpu)
34{
35 /*
36 * if any interrupts are already enabled for the primary
37 * core (e.g. timer irq), then they will not have been enabled
38 * for us: do so
39 */
40 gic_secondary_init(0);
41
42 /*
43 * let the primary processor know we're out of the
44 * pen, then head off into the C entry point
45 */
46 pen_release = -1;
47 smp_wmb();
48
49 /*
50 * Synchronise with the boot thread.
51 */
52 spin_lock(&boot_lock);
53 spin_unlock(&boot_lock);
54}
55
56int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
57{
58 unsigned long timeout;
59
60 /*
61 * set synchronisation state between this boot processor
62 * and the secondary one
63 */
64 spin_lock(&boot_lock);
65
66 /*
67 * The secondary processor is waiting to be released from
68 * the holding pen - release it, then wait for it to flag
69 * that it has been released by resetting pen_release.
70 *
71 * Note that "pen_release" is the hardware CPU ID, whereas
72 * "cpu" is Linux's internal ID.
73 */
74 pen_release = cpu;
75 flush_cache_all();
76 outer_flush_all();
77
78 timeout = jiffies + (1 * HZ);
79 while (time_before(jiffies, timeout)) {
80 smp_rmb();
81 if (pen_release == -1)
82 break;
83
84 udelay(10);
85 }
86
87 /*
88 * now the secondary core is starting up let it run its
89 * calibrations, then wait for it to finish
90 */
91 spin_unlock(&boot_lock);
92
93 return pen_release != -1 ? -ENOSYS : 0;
94}
95
96/*
97 * Initialise the CPU possible map early - this describes the CPUs
98 * which may be present or become present in the system.
99 */
100void __init smp_init_cpus(void)
101{
102 unsigned int i, ncores = scu_get_core_count(scu_base);
103
104 if (ncores > nr_cpu_ids) {
105 pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
106 ncores, nr_cpu_ids);
107 ncores = nr_cpu_ids;
108 }
109
110 for (i = 0; i < ncores; i++)
111 set_cpu_possible(i, true);
112
113 set_smp_cross_call(gic_raise_softirq);
114}
115
116void __init platform_smp_prepare_cpus(unsigned int max_cpus)
117{
118
119 scu_enable(scu_base);
120
121 /*
122 * Write the address of secondary startup into the system-wide location
123 * (presently it is in SRAM). The BootMonitor waits until it receives a
124 * soft interrupt, and then the secondary CPU branches to this address.
125 */
126 __raw_writel(virt_to_phys(spear13xx_secondary_startup), SYS_LOCATION);
127}