ARM: suspend: use idmap_pgd instead of suspend_pgd
The ARM CPU suspend code requires cpu_resume_mmu to be identity mapped
in order to re-enable the MMU when coming out of suspend. Currently,
this is accomplished by maintaining a suspend_pgd with the relevant
mapping put in place at init time.
This patch replaces the use of suspend_pgd with the new idmap_pgd.
cpu_resume_mmu is placed in the .idmap.text section so that it is
included in the identity map.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Dave Martin <dave.martin@linaro.org>
Tested-by: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
diff --git a/arch/arm/kernel/suspend.c b/arch/arm/kernel/suspend.c
index 93a22d2..1794cc3 100644
--- a/arch/arm/kernel/suspend.c
+++ b/arch/arm/kernel/suspend.c
@@ -1,13 +1,12 @@
#include <linux/init.h>
+#include <asm/idmap.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/memory.h>
#include <asm/suspend.h>
#include <asm/tlbflush.h>
-static pgd_t *suspend_pgd;
-
extern int __cpu_suspend(unsigned long, int (*)(unsigned long));
extern void cpu_resume_mmu(void);
@@ -21,7 +20,7 @@
*save_ptr = virt_to_phys(ptr);
/* This must correspond to the LDM in cpu_resume() assembly */
- *ptr++ = virt_to_phys(suspend_pgd);
+ *ptr++ = virt_to_phys(idmap_pgd);
*ptr++ = sp;
*ptr++ = virt_to_phys(cpu_do_resume);
@@ -42,7 +41,7 @@
struct mm_struct *mm = current->active_mm;
int ret;
- if (!suspend_pgd)
+ if (!idmap_pgd)
return -EINVAL;
/*
@@ -59,14 +58,3 @@
return ret;
}
-
-static int __init cpu_suspend_init(void)
-{
- suspend_pgd = pgd_alloc(&init_mm);
- if (suspend_pgd) {
- unsigned long addr = virt_to_phys(cpu_resume_mmu);
- identity_mapping_add(suspend_pgd, addr, addr + SECTION_SIZE);
- }
- return suspend_pgd ? 0 : -ENOMEM;
-}
-core_initcall(cpu_suspend_init);
