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diff --git a/target/linux/cns3xxx/files/arch/arm/mach-cns3xxx/platsmp.c b/target/linux/cns3xxx/files/arch/arm/mach-cns3xxx/platsmp.c
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+++ b/target/linux/cns3xxx/files/arch/arm/mach-cns3xxx/platsmp.c
@@ -0,0 +1,337 @@
+/*
+ * linux/arch/arm/mach-cns3xxx/platsmp.c
+ *
+ * Copyright (C) 2002 ARM Ltd.
+ * Copyright 2012 Gateworks Corporation
+ * Chris Lang <clang@gateworks.com>
+ * Tim Harvey <tharvey@gateworks.com>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/jiffies.h>
+#include <linux/smp.h>
+#include <linux/io.h>
+
+#include <asm/cacheflush.h>
+#include <asm/smp_scu.h>
+#include <asm/unified.h>
+#include <asm/fiq.h>
+#include <mach/smp.h>
+#include "cns3xxx.h"
+
+static struct fiq_handler fh = {
+ .name = "cns3xxx-fiq"
+};
+
+struct fiq_req {
+ union {
+ struct {
+ const void *addr;
+ size_t size;
+ } map;
+ struct {
+ const void *addr;
+ size_t size;
+ } unmap;
+ struct {
+ const void *start;
+ const void *end;
+ } flush;
+ };
+ volatile uint flags;
+ void __iomem *reg;
+} ____cacheline_aligned;
+
+extern unsigned int fiq_number[2];
+
+DEFINE_PER_CPU(struct fiq_req, fiq_data);
+
+#define FIQ_ENABLED 0x80000000
+#define FIQ_GENERATE 0x00010000
+#define CNS3XXX_MAP_AREA 0x01000000
+#define CNS3XXX_UNMAP_AREA 0x02000000
+#define CNS3XXX_FLUSH_RANGE 0x03000000
+
+extern void cns3xxx_secondary_startup(void);
+extern unsigned char cns3xxx_fiq_start, cns3xxx_fiq_end;
+
+#define SCU_CPU_STATUS 0x08
+static void __iomem *scu_base;
+
+static inline void __cpuinit cns3xxx_set_fiq_regs(unsigned int cpu)
+{
+ struct pt_regs FIQ_regs;
+ struct fiq_req *fiq_req = &per_cpu(fiq_data, !cpu);
+
+ FIQ_regs.ARM_r8 = 0;
+ FIQ_regs.ARM_ip = (unsigned int)fiq_req;
+ FIQ_regs.ARM_sp = (int) MISC_FIQ_CPU(!cpu);
+ fiq_req->reg = MISC_FIQ_CPU(!cpu);
+
+ set_fiq_regs(&FIQ_regs);
+}
+
+static void __init cns3xxx_init_fiq(void)
+{
+ void *fiqhandler_start;
+ unsigned int fiqhandler_length;
+ int ret;
+
+ fiqhandler_start = &cns3xxx_fiq_start;
+ fiqhandler_length = &cns3xxx_fiq_end - &cns3xxx_fiq_start;
+
+ ret = claim_fiq(&fh);
+ if (ret)
+ return;
+
+ set_fiq_handler(fiqhandler_start, fiqhandler_length);
+}
+
+
+/*
+ * Write pen_release in a way that is guaranteed to be visible to all
+ * observers, irrespective of whether they're taking part in coherency
+ * or not. This is necessary for the hotplug code to work reliably.
+ */
+static void __cpuinit write_pen_release(int val)
+{
+ pen_release = val;
+ smp_wmb();
+ __cpuc_flush_dcache_area((void *)&pen_release, sizeof(pen_release));
+ outer_clean_range(__pa(&pen_release), __pa(&pen_release + 1));
+}
+
+static DEFINE_SPINLOCK(boot_lock);
+
+static void __cpuinit cns3xxx_secondary_init(unsigned int cpu)
+{
+ /*
+ * Setup Secondary Core FIQ regs
+ */
+ cns3xxx_set_fiq_regs(1);
+
+ /*
+ * let the primary processor know we're out of the
+ * pen, then head off into the C entry point
+ */
+ write_pen_release(-1);
+
+ /*
+ * Synchronise with the boot thread.
+ */
+ spin_lock(&boot_lock);
+ spin_unlock(&boot_lock);
+}
+
+static int __cpuinit cns3xxx_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ unsigned long timeout;
+
+ /*
+ * Set synchronisation state between this boot processor
+ * and the secondary one
+ */
+ spin_lock(&boot_lock);
+
+ /*
+ * The secondary processor is waiting to be released from
+ * the holding pen - release it, then wait for it to flag
+ * that it has been released by resetting pen_release.
+ *
+ * Note that "pen_release" is the hardware CPU ID, whereas
+ * "cpu" is Linux's internal ID.
+ */
+ write_pen_release(cpu);
+
+ /*
+ * Send the secondary CPU a soft interrupt, thereby causing
+ * the boot monitor to read the system wide flags register,
+ * and branch to the address found there.
+ */
+ arch_send_wakeup_ipi_mask(cpumask_of(cpu));;
+
+ timeout = jiffies + (1 * HZ);
+ while (time_before(jiffies, timeout)) {
+ smp_rmb();
+ if (pen_release == -1)
+ break;
+
+ udelay(10);
+ }
+
+ /*
+ * now the secondary core is starting up let it run its
+ * calibrations, then wait for it to finish
+ */
+ spin_unlock(&boot_lock);
+
+ return pen_release != -1 ? -ENOSYS : 0;
+}
+
+/*
+ * Initialise the CPU possible map early - this describes the CPUs
+ * which may be present or become present in the system.
+ */
+static void __init cns3xxx_smp_init_cpus(void)
+{
+ unsigned int i, ncores;
+ unsigned int status;
+
+ scu_base = (void __iomem *) CNS3XXX_TC11MP_SCU_BASE_VIRT;
+
+ /* for CNS3xxx SCU_CPU_STATUS must be examined instead of SCU_CONFIGURATION
+ * used in scu_get_core_count
+ */
+ status = __raw_readl(scu_base + SCU_CPU_STATUS);
+ for (i = 0; i < NR_CPUS+1; i++) {
+ if (((status >> (i*2)) & 0x3) == 0)
+ set_cpu_possible(i, true);
+ else
+ break;
+ }
+ ncores = i;
+}
+
+static void __init cns3xxx_smp_prepare_cpus(unsigned int max_cpus)
+{
+ int i;
+
+ /*
+ * Initialise the present map, which describes the set of CPUs
+ * actually populated at the present time.
+ */
+ for (i = 0; i < max_cpus; i++) {
+ set_cpu_present(i, true);
+ }
+
+ /*
+ * enable SCU
+ */
+ scu_enable(scu_base);
+
+ /*
+ * Write the address of secondary startup into the
+ * system-wide flags register. The boot monitor waits
+ * until it receives a soft interrupt, and then the
+ * secondary CPU branches to this address.
+ */
+ __raw_writel(virt_to_phys(cns3xxx_secondary_startup),
+ (void __iomem *)(CNS3XXX_MISC_BASE_VIRT + 0x0600));
+
+ /*
+ * Setup FIQ's for main cpu
+ */
+ cns3xxx_init_fiq();
+ cns3xxx_set_fiq_regs(0);
+}
+
+extern void v6_dma_map_area(const void *, size_t, int);
+extern void v6_dma_unmap_area(const void *, size_t, int);
+extern void v6_dma_flush_range(const void *, const void *);
+extern void v6_flush_kern_dcache_area(void *, size_t);
+
+void fiq_dma_map_area(const void *addr, size_t size, int dir)
+{
+ unsigned long flags;
+ struct fiq_req *req;
+
+ raw_local_irq_save(flags);
+ /* currently, not possible to take cpu0 down, so only check cpu1 */
+ if (!cpu_online(1)) {
+ raw_local_irq_restore(flags);
+ v6_dma_map_area(addr, size, dir);
+ return;
+ }
+
+ req = this_cpu_ptr(&fiq_data);
+ req->map.addr = addr;
+ req->map.size = size;
+ req->flags = dir | CNS3XXX_MAP_AREA;
+ smp_mb();
+
+ writel_relaxed(FIQ_GENERATE, req->reg);
+
+ v6_dma_map_area(addr, size, dir);
+ while (req->flags)
+ barrier();
+
+ raw_local_irq_restore(flags);
+}
+
+void fiq_dma_unmap_area(const void *addr, size_t size, int dir)
+{
+ unsigned long flags;
+ struct fiq_req *req;
+
+ raw_local_irq_save(flags);
+ /* currently, not possible to take cpu0 down, so only check cpu1 */
+ if (!cpu_online(1)) {
+ raw_local_irq_restore(flags);
+ v6_dma_unmap_area(addr, size, dir);
+ return;
+ }
+
+ req = this_cpu_ptr(&fiq_data);
+ req->unmap.addr = addr;
+ req->unmap.size = size;
+ req->flags = dir | CNS3XXX_UNMAP_AREA;
+ smp_mb();
+
+ writel_relaxed(FIQ_GENERATE, req->reg);
+
+ v6_dma_unmap_area(addr, size, dir);
+ while (req->flags)
+ barrier();
+
+ raw_local_irq_restore(flags);
+}
+
+void fiq_dma_flush_range(const void *start, const void *end)
+{
+ unsigned long flags;
+ struct fiq_req *req;
+
+ raw_local_irq_save(flags);
+ /* currently, not possible to take cpu0 down, so only check cpu1 */
+ if (!cpu_online(1)) {
+ raw_local_irq_restore(flags);
+ v6_dma_flush_range(start, end);
+ return;
+ }
+
+ req = this_cpu_ptr(&fiq_data);
+
+ req->flush.start = start;
+ req->flush.end = end;
+ req->flags = CNS3XXX_FLUSH_RANGE;
+ smp_mb();
+
+ writel_relaxed(FIQ_GENERATE, req->reg);
+
+ v6_dma_flush_range(start, end);
+
+ while (req->flags)
+ barrier();
+
+ raw_local_irq_restore(flags);
+}
+
+void fiq_flush_kern_dcache_area(void *addr, size_t size)
+{
+ fiq_dma_flush_range(addr, addr + size);
+}
+
+struct smp_operations cns3xxx_smp_ops __initdata = {
+ .smp_init_cpus = cns3xxx_smp_init_cpus,
+ .smp_prepare_cpus = cns3xxx_smp_prepare_cpus,
+ .smp_secondary_init = cns3xxx_secondary_init,
+ .smp_boot_secondary = cns3xxx_boot_secondary,
+};