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Diffstat (limited to 'arch/arm/mach-vexpress/platsmp.c')
-rw-r--r--arch/arm/mach-vexpress/platsmp.c155
1 files changed, 153 insertions, 2 deletions
diff --git a/arch/arm/mach-vexpress/platsmp.c b/arch/arm/mach-vexpress/platsmp.c
index a1ed6d68597d..14ba1128ae8d 100644
--- a/arch/arm/mach-vexpress/platsmp.c
+++ b/arch/arm/mach-vexpress/platsmp.c
@@ -12,6 +12,11 @@
#include <linux/errno.h>
#include <linux/smp.h>
#include <linux/io.h>
+#include <linux/of_fdt.h>
+
+#include <asm/smp_scu.h>
+#include <asm/hardware/gic.h>
+#include <asm/mach/map.h>
#include <mach/motherboard.h>
@@ -19,13 +24,156 @@
extern void versatile_secondary_startup(void);
+#if defined(CONFIG_OF)
+
+static enum {
+ GENERIC_SCU,
+ CORTEX_A9_SCU,
+} vexpress_dt_scu __initdata = GENERIC_SCU;
+
+static struct map_desc vexpress_dt_cortex_a9_scu_map __initdata = {
+ .virtual = V2T_PERIPH,
+ /* .pfn set in vexpress_dt_init_cortex_a9_scu() */
+ .length = SZ_128,
+ .type = MT_DEVICE,
+};
+
+static void *vexpress_dt_cortex_a9_scu_base __initdata;
+
+const static char *vexpress_dt_cortex_a9_match[] __initconst = {
+ "arm,cortex-a5-scu",
+ "arm,cortex-a9-scu",
+ NULL
+};
+
+static int __init vexpress_dt_find_scu(unsigned long node,
+ const char *uname, int depth, void *data)
+{
+ if (of_flat_dt_match(node, vexpress_dt_cortex_a9_match)) {
+ phys_addr_t phys_addr;
+ __be32 *reg = of_get_flat_dt_prop(node, "reg", NULL);
+
+ if (WARN_ON(!reg))
+ return -EINVAL;
+
+ phys_addr = be32_to_cpup(reg);
+ vexpress_dt_scu = CORTEX_A9_SCU;
+
+ vexpress_dt_cortex_a9_scu_map.pfn = __phys_to_pfn(phys_addr);
+ iotable_init(&vexpress_dt_cortex_a9_scu_map, 1);
+ vexpress_dt_cortex_a9_scu_base = ioremap(phys_addr, SZ_256);
+ if (WARN_ON(!vexpress_dt_cortex_a9_scu_base))
+ return -EFAULT;
+ }
+
+ return 0;
+}
+
+void __init vexpress_dt_smp_map_io(void)
+{
+ if (initial_boot_params)
+ WARN_ON(of_scan_flat_dt(vexpress_dt_find_scu, NULL));
+}
+
+static int __init vexpress_dt_cpus_num(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ static int prev_depth = -1;
+ static int nr_cpus = -1;
+
+ if (prev_depth > depth && nr_cpus > 0)
+ return nr_cpus;
+
+ if (nr_cpus < 0 && strcmp(uname, "cpus") == 0)
+ nr_cpus = 0;
+
+ if (nr_cpus >= 0) {
+ const char *device_type = of_get_flat_dt_prop(node,
+ "device_type", NULL);
+
+ if (device_type && strcmp(device_type, "cpu") == 0)
+ nr_cpus++;
+ }
+
+ prev_depth = depth;
+
+ return 0;
+}
+
+static void __init vexpress_dt_smp_init_cpus(void)
+{
+ int ncores = 0, i;
+
+ switch (vexpress_dt_scu) {
+ case GENERIC_SCU:
+ ncores = of_scan_flat_dt(vexpress_dt_cpus_num, NULL);
+ break;
+ case CORTEX_A9_SCU:
+ ncores = scu_get_core_count(vexpress_dt_cortex_a9_scu_base);
+ break;
+ default:
+ WARN_ON(1);
+ break;
+ }
+
+ if (ncores < 2)
+ return;
+
+ if (ncores > nr_cpu_ids) {
+ pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
+ ncores, nr_cpu_ids);
+ ncores = nr_cpu_ids;
+ }
+
+ for (i = 0; i < ncores; ++i)
+ set_cpu_possible(i, true);
+
+ set_smp_cross_call(gic_raise_softirq);
+}
+
+static void __init vexpress_dt_smp_prepare_cpus(unsigned int max_cpus)
+{
+ int i;
+
+ switch (vexpress_dt_scu) {
+ case GENERIC_SCU:
+ for (i = 0; i < max_cpus; i++)
+ set_cpu_present(i, true);
+ break;
+ case CORTEX_A9_SCU:
+ scu_enable(vexpress_dt_cortex_a9_scu_base);
+ break;
+ default:
+ WARN_ON(1);
+ break;
+ }
+}
+
+#else
+
+static void __init vexpress_dt_smp_init_cpus(void)
+{
+ WARN_ON(1);
+}
+
+void __init vexpress_dt_smp_prepare_cpus(unsigned int max_cpus)
+{
+ WARN_ON(1);
+}
+
+#endif
+
/*
* Initialise the CPU possible map early - this describes the CPUs
* which may be present or become present in the system.
*/
void __init smp_init_cpus(void)
{
- ct_desc->init_cpu_map();
+ if (ct_desc)
+ ct_desc->init_cpu_map();
+ else
+ vexpress_dt_smp_init_cpus();
+
}
void __init platform_smp_prepare_cpus(unsigned int max_cpus)
@@ -34,7 +182,10 @@ void __init platform_smp_prepare_cpus(unsigned int max_cpus)
* Initialise the present map, which describes the set of CPUs
* actually populated at the present time.
*/
- ct_desc->smp_enable(max_cpus);
+ if (ct_desc)
+ ct_desc->smp_enable(max_cpus);
+ else
+ vexpress_dt_smp_prepare_cpus(max_cpus);
/*
* Write the address of secondary startup into the