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ARM: suspend: fix CPU suspend code for !CONFIG_MMU configurations

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The ARM CPU suspend code can be selected even for a !CONFIG_MMU
configuration. The resulting kernel will not compile and, even if it did,
would access undefined co-processor registers when executing.

This patch fixes the v6 and v7 CPU suspend code for the nommu case.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Tested-by: Jonathan Austin <jonathan.austin@arm.com>
CC: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> (commit_signer:1/3=33%)
CC: Santosh Shilimkar <santosh.shilimkar@ti.com> (commit_signer:1/3=33%)
CC: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
This commit is contained in:
Will Deacon
2012-02-23 13:51:38 +00:00
committed by Jonathan Austin
parent c4a1f032ed
commit aa1aadc330
3 changed files with 50 additions and 34 deletions
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64
arch/arm/kernel/suspend.c
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@@ -10,6 +10,42 @@
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
@@ -46,31 +82,3 @@ void __cpu_suspend_save(u32 *ptr, u32 ptrsz, u32 sp, u32 *save_ptr)
outer_clean_range(virt_to_phys(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;
/*
* 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;
}