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authorRussell King <rmk+kernel@arm.linux.org.uk>2011-01-06 17:31:35 -0500
committerRussell King <rmk+kernel@arm.linux.org.uk>2011-01-06 17:32:03 -0500
commit4ec3eb13634529c0bc7466658d84d0bbe3244aea (patch)
treeb491daac2ccfc7b8ca88e171a43f66888463568a /arch/arm/mach-vexpress/platsmp.c
parent24056f525051a9e186af28904b396320e18bf9a0 (diff)
parent15095bb0fe779c0403091bda7adce5fb3bb9ca35 (diff)
Merge branch 'smp' into misc
Conflicts: arch/arm/kernel/entry-armv.S arch/arm/mm/ioremap.c
Diffstat (limited to 'arch/arm/mach-vexpress/platsmp.c')
-rw-r--r--arch/arm/mach-vexpress/platsmp.c74
1 files changed, 26 insertions, 48 deletions
diff --git a/arch/arm/mach-vexpress/platsmp.c b/arch/arm/mach-vexpress/platsmp.c
index 670970699ba..8ce9fef2955 100644
--- a/arch/arm/mach-vexpress/platsmp.c
+++ b/arch/arm/mach-vexpress/platsmp.c
@@ -17,7 +17,6 @@
17#include <linux/io.h> 17#include <linux/io.h>
18 18
19#include <asm/cacheflush.h> 19#include <asm/cacheflush.h>
20#include <asm/localtimer.h>
21#include <asm/smp_scu.h> 20#include <asm/smp_scu.h>
22#include <asm/unified.h> 21#include <asm/unified.h>
23 22
@@ -35,6 +34,19 @@ extern void vexpress_secondary_startup(void);
35 */ 34 */
36volatile int __cpuinitdata pen_release = -1; 35volatile int __cpuinitdata pen_release = -1;
37 36
37/*
38 * Write pen_release in a way that is guaranteed to be visible to all
39 * observers, irrespective of whether they're taking part in coherency
40 * or not. This is necessary for the hotplug code to work reliably.
41 */
42static void write_pen_release(int val)
43{
44 pen_release = val;
45 smp_wmb();
46 __cpuc_flush_dcache_area((void *)&pen_release, sizeof(pen_release));
47 outer_clean_range(__pa(&pen_release), __pa(&pen_release + 1));
48}
49
38static void __iomem *scu_base_addr(void) 50static void __iomem *scu_base_addr(void)
39{ 51{
40 return MMIO_P2V(A9_MPCORE_SCU); 52 return MMIO_P2V(A9_MPCORE_SCU);
@@ -44,8 +56,6 @@ static DEFINE_SPINLOCK(boot_lock);
44 56
45void __cpuinit platform_secondary_init(unsigned int cpu) 57void __cpuinit platform_secondary_init(unsigned int cpu)
46{ 58{
47 trace_hardirqs_off();
48
49 /* 59 /*
50 * if any interrupts are already enabled for the primary 60 * if any interrupts are already enabled for the primary
51 * core (e.g. timer irq), then they will not have been enabled 61 * core (e.g. timer irq), then they will not have been enabled
@@ -57,8 +67,7 @@ void __cpuinit platform_secondary_init(unsigned int cpu)
57 * let the primary processor know we're out of the 67 * let the primary processor know we're out of the
58 * pen, then head off into the C entry point 68 * pen, then head off into the C entry point
59 */ 69 */
60 pen_release = -1; 70 write_pen_release(-1);
61 smp_wmb();
62 71
63 /* 72 /*
64 * Synchronise with the boot thread. 73 * Synchronise with the boot thread.
@@ -83,16 +92,14 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
83 * since we haven't sent them a soft interrupt, they shouldn't 92 * since we haven't sent them a soft interrupt, they shouldn't
84 * be there. 93 * be there.
85 */ 94 */
86 pen_release = cpu; 95 write_pen_release(cpu);
87 __cpuc_flush_dcache_area((void *)&pen_release, sizeof(pen_release));
88 outer_clean_range(__pa(&pen_release), __pa(&pen_release + 1));
89 96
90 /* 97 /*
91 * Send the secondary CPU a soft interrupt, thereby causing 98 * Send the secondary CPU a soft interrupt, thereby causing
92 * the boot monitor to read the system wide flags register, 99 * the boot monitor to read the system wide flags register,
93 * and branch to the address found there. 100 * and branch to the address found there.
94 */ 101 */
95 smp_cross_call(cpumask_of(cpu)); 102 smp_cross_call(cpumask_of(cpu), 1);
96 103
97 timeout = jiffies + (1 * HZ); 104 timeout = jiffies + (1 * HZ);
98 while (time_before(jiffies, timeout)) { 105 while (time_before(jiffies, timeout)) {
@@ -124,13 +131,6 @@ void __init smp_init_cpus(void)
124 ncores = scu_base ? scu_get_core_count(scu_base) : 1; 131 ncores = scu_base ? scu_get_core_count(scu_base) : 1;
125 132
126 /* sanity check */ 133 /* sanity check */
127 if (ncores == 0) {
128 printk(KERN_ERR
129 "vexpress: strange CM count of 0? Default to 1\n");
130
131 ncores = 1;
132 }
133
134 if (ncores > NR_CPUS) { 134 if (ncores > NR_CPUS) {
135 printk(KERN_WARNING 135 printk(KERN_WARNING
136 "vexpress: no. of cores (%d) greater than configured " 136 "vexpress: no. of cores (%d) greater than configured "
@@ -143,20 +143,10 @@ void __init smp_init_cpus(void)
143 set_cpu_possible(i, true); 143 set_cpu_possible(i, true);
144} 144}
145 145
146void __init smp_prepare_cpus(unsigned int max_cpus) 146void __init platform_smp_prepare_cpus(unsigned int max_cpus)
147{ 147{
148 unsigned int ncores = num_possible_cpus();
149 unsigned int cpu = smp_processor_id();
150 int i; 148 int i;
151 149
152 smp_store_cpu_info(cpu);
153
154 /*
155 * are we trying to boot more cores than exist?
156 */
157 if (max_cpus > ncores)
158 max_cpus = ncores;
159
160 /* 150 /*
161 * Initialise the present map, which describes the set of CPUs 151 * Initialise the present map, which describes the set of CPUs
162 * actually populated at the present time. 152 * actually populated at the present time.
@@ -164,27 +154,15 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
164 for (i = 0; i < max_cpus; i++) 154 for (i = 0; i < max_cpus; i++)
165 set_cpu_present(i, true); 155 set_cpu_present(i, true);
166 156
157 scu_enable(scu_base_addr());
158
167 /* 159 /*
168 * Initialise the SCU if there are more than one CPU and let 160 * Write the address of secondary startup into the
169 * them know where to start. 161 * system-wide flags register. The boot monitor waits
162 * until it receives a soft interrupt, and then the
163 * secondary CPU branches to this address.
170 */ 164 */
171 if (max_cpus > 1) { 165 writel(~0, MMIO_P2V(V2M_SYS_FLAGSCLR));
172 /* 166 writel(BSYM(virt_to_phys(vexpress_secondary_startup)),
173 * Enable the local timer or broadcast device for the 167 MMIO_P2V(V2M_SYS_FLAGSSET));
174 * boot CPU, but only if we have more than one CPU.
175 */
176 percpu_timer_setup();
177
178 scu_enable(scu_base_addr());
179
180 /*
181 * Write the address of secondary startup into the
182 * system-wide flags register. The boot monitor waits
183 * until it receives a soft interrupt, and then the
184 * secondary CPU branches to this address.
185 */
186 writel(~0, MMIO_P2V(V2M_SYS_FLAGSCLR));
187 writel(BSYM(virt_to_phys(vexpress_secondary_startup)),
188 MMIO_P2V(V2M_SYS_FLAGSSET));
189 }
190} 168}