ARM: kernel: implement stack pointer save array through MPIDR hashing

[linux-2.6-microblaze.git] / arch / arm / kernel / suspend.c

diff --git a/arch/arm/kernel/suspend.c b/arch/arm/kernel/suspend.c
index c59c97e..41cf3cb 100644 (file)
--- a/arch/arm/kernel/suspend.c
+++ b/arch/arm/kernel/suspend.c
@@ -1,15 +1,54 @@
 #include <linux/init.h>
+#include <linux/slab.h>
 
+#include <asm/cacheflush.h>
 #include <asm/idmap.h>
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
 #include <asm/memory.h>
+#include <asm/smp_plat.h>
 #include <asm/suspend.h>
 #include <asm/tlbflush.h>
 
 extern int __cpu_suspend(unsigned long, int (*)(unsigned long));
 extern void cpu_resume_mmu(void);
 
+#ifdef CONFIG_MMU
+/*
+ * Hide the first two arguments to __cpu_suspend - these are an implementation
+ * detail which platform code shouldn't have to know about.
+ */
+int cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
+{
+       struct mm_struct *mm = current->active_mm;
+       int ret;
+
+       if (!idmap_pgd)
+               return -EINVAL;
+
+       /*
+        * Provide a temporary page table with an identity mapping for
+        * the MMU-enable code, required for resuming.  On successful
+        * resume (indicated by a zero return code), we need to switch
+        * back to the correct page tables.
+        */
+       ret = __cpu_suspend(arg, fn);
+       if (ret == 0) {
+               cpu_switch_mm(mm->pgd, mm);
+               local_flush_bp_all();
+               local_flush_tlb_all();
+       }
+
+       return ret;
+}
+#else
+int cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
+{
+       return __cpu_suspend(arg, fn);
+}
+#define        idmap_pgd       NULL
+#endif
+
 /*
  * This is called by __cpu_suspend() to save the state, and do whatever
  * flushing is required to ensure that when the CPU goes to sleep we have
@@ -47,30 +86,19 @@ void __cpu_suspend_save(u32 *ptr, u32 ptrsz, u32 sp, u32 *save_ptr)
                          virt_to_phys(save_ptr) + sizeof(*save_ptr));
 }
 
-/*
- * Hide the first two arguments to __cpu_suspend - these are an implementation
- * detail which platform code shouldn't have to know about.
- */
-int cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
-{
-       struct mm_struct *mm = current->active_mm;
-       int ret;
-
-       if (!idmap_pgd)
-               return -EINVAL;
+extern struct sleep_save_sp sleep_save_sp;
 
-       /*
-        * Provide a temporary page table with an identity mapping for
-        * the MMU-enable code, required for resuming.  On successful
-        * resume (indicated by a zero return code), we need to switch
-        * back to the correct page tables.
-        */
-       ret = __cpu_suspend(arg, fn);
-       if (ret == 0) {
-               cpu_switch_mm(mm->pgd, mm);
-               local_flush_bp_all();
-               local_flush_tlb_all();
-       }
+static int cpu_suspend_alloc_sp(void)
+{
+       void *ctx_ptr;
+       /* ctx_ptr is an array of physical addresses */
+       ctx_ptr = kcalloc(mpidr_hash_size(), sizeof(u32), GFP_KERNEL);
 
-       return ret;
+       if (WARN_ON(!ctx_ptr))
+               return -ENOMEM;
+       sleep_save_sp.save_ptr_stash = ctx_ptr;
+       sleep_save_sp.save_ptr_stash_phys = virt_to_phys(ctx_ptr);
+       sync_cache_w(&sleep_save_sp);
+       return 0;
 }
+early_initcall(cpu_suspend_alloc_sp);