[PATCH v2 06/28] ARM: mmu: Share code for create_sections()

[Andrey Smirnov]

On Wed, May 16, 2018 at 1:49 PM, Sam Ravnborg <sam at ravnborg.org> wrote:
> Hi Andrey
>
> On Wed, May 16, 2018 at 01:00:14PM -0700, Andrey Smirnov wrote:
>> Regular MMU code never creates anything but 1:1 mapping, and barring
>> that plus the call to __mmu_cache_flush(), early MMU code version of
>> the function is pretty much identical. To avoid code duplication, move
>> it to mmu.h and convert both regular and early MMU code to use it.
>>
>> Signed-off-by: Andrey Smirnov <andrew.smirnov at gmail.com>
>> ---
>>  arch/arm/cpu/mmu-early.c | 14 ++------------
>>  arch/arm/cpu/mmu.c       | 25 +++++++------------------
>>  arch/arm/cpu/mmu.h       |  8 ++++++++
>>  3 files changed, 17 insertions(+), 30 deletions(-)
>>
>> diff --git a/arch/arm/cpu/mmu-early.c b/arch/arm/cpu/mmu-early.c
>> index f75cc7e4a..70ece0d2f 100644
>> --- a/arch/arm/cpu/mmu-early.c
>> +++ b/arch/arm/cpu/mmu-early.c
>> @@ -11,22 +11,12 @@
>>
>>  static uint32_t *ttb;
>>
>> -static void create_sections(unsigned long addr, int size_m, unsigned int flags)
>> -{
>> -     int i;
>> -
>> -     addr >>= 20;
>> -
>> -     for (i = size_m; i > 0; i--, addr++)
>> -             ttb[addr] = (addr << 20) | flags;
>> -}
> This iterates in the for loop size_m times.
>
>> -
>> -static void create_sections(unsigned long virt, unsigned long phys, int size_m,
>> -             unsigned int flags)
>> -{
>> -     int i;
>> -
>> -     phys >>= 20;
>> -     virt >>= 20;
>> -
>> -     for (i = size_m; i > 0; i--, virt++, phys++)
>> -             ttb[virt] = (phys << 20) | flags;
>> -
>> -     __mmu_cache_flush();
>> -}
> likewise
>
>> +++ b/arch/arm/cpu/mmu.h
>> @@ -24,5 +24,13 @@ static inline void set_domain(unsigned val)
>>       asm volatile ("mcr  p15,0,%0,c3,c0,0" : : "r"(val) /*:*/);
>>  }
>>
>> +static inline void
>> +create_sections(uint32_t *ttb, unsigned long addr,
>> +             int size_m, unsigned int flags)
>> +{
>> +     for (addr >>= 20; addr < size_m; addr++)
>> +             ttb[addr] = (addr << 20) | flags;
>> +}
>
> But this iterates in the for loop while addr >> 20 is less than size_m.
> I cannot see from the code nor the changelog if this is an intentional change
>
> (I only stumbled over this while browsing the patch, no testing done)
>

Good catch! Not intentional at all. Will fix in v3.

Thanks,
Andrey Smirnov