1 files changed, 19 insertions, 2 deletions

diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
index 04160a4cc699..a15f582300d8 100644
--- a/arch/powerpc/platforms/85xx/smp.c
+++ b/arch/powerpc/platforms/85xx/smp.c
@@ -46,6 +46,7 @@ smp_85xx_kick_cpu(int nr)
         __iomem u32 *bptr_vaddr;
         struct device_node *np;
         int n = 0;
+        int ioremappable;
 
         WARN_ON (nr < 0 || nr >= NR_CPUS);
 
@@ -59,21 +60,37 @@ smp_85xx_kick_cpu(int nr)
                 return;
         }
 
+        /*
+         * A secondary core could be in a spinloop in the bootpage
+         * (0xfffff000), somewhere in highmem, or somewhere in lowmem.
+         * The bootpage and highmem can be accessed via ioremap(), but
+         * we need to directly access the spinloop if its in lowmem.
+         */
+        ioremappable = *cpu_rel_addr > virt_to_phys(high_memory);
+
         /* Map the spin table */
-        bptr_vaddr = ioremap(*cpu_rel_addr, SIZE_BOOT_ENTRY);
+        if (ioremappable)
+                bptr_vaddr = ioremap(*cpu_rel_addr, SIZE_BOOT_ENTRY);
+        else
+                bptr_vaddr = phys_to_virt(*cpu_rel_addr);
 
         local_irq_save(flags);
 
         out_be32(bptr_vaddr + BOOT_ENTRY_PIR, nr);
         out_be32(bptr_vaddr + BOOT_ENTRY_ADDR_LOWER, __pa(__early_start));
 
+        if (!ioremappable)
+                flush_dcache_range((ulong)bptr_vaddr,
+                                (ulong)(bptr_vaddr + SIZE_BOOT_ENTRY));
+
         /* Wait a bit for the CPU to ack. */
         while ((__secondary_hold_acknowledge != nr) && (++n < 1000))
                 mdelay(1);
 
         local_irq_restore(flags);
 
-        iounmap(bptr_vaddr);
+        if (ioremappable)
+                iounmap(bptr_vaddr);
 
         pr_debug("waited %d msecs for CPU #%d.\n", n, nr);
 }