[U-Boot] [PATCH] Fix wrong loop bound in flush_cache() when "size" is zero.

[Saturday Coder]

Hi Sergei, thanks for your comments.
I will submit the patch v2.

2011/8/8 Sergei Shtylyov <sshtylyov at mvista.com>

> Hello.
>
>
> On 08-08-2011 12:07, Yao Cheng wrote:
>
>  The issue is found when calling flush_cache() with zero "size" argument.
>> The bound of loop is miscalculated in this case and flush_cache() enters a
>> wrong flushing loop.
>> To fix this issue I skipped the operations when "size" is found to be
>> zero.
>>
>
>  Signed-off-by: Yao Cheng<saturdaycoder at gmail.com>
>> Cc: Shinya Kuribayashi<skuribay at pobox.com**>
>> ---
>>  arch/mips/cpu/mips32/cpu.c |    5 +++++
>>  1 files changed, 5 insertions(+), 0 deletions(-)
>>
>
>  diff --git a/arch/mips/cpu/mips32/cpu.c b/arch/mips/cpu/mips32/cpu.c
>> index 3ae397c..1bf0094 100644
>> --- a/arch/mips/cpu/mips32/cpu.c
>> +++ b/arch/mips/cpu/mips32/cpu.c
>> @@ -52,6 +52,11 @@ int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char
>> * const argv[])
>>
>>  void flush_cache(ulong start_addr, ulong size)
>>  {
>> +  /* aend will be miscalculated when size is zero, so we need return here
>> */
>> +  if (size == 0) {
>> +    return;
>> +  }
>>
> > +
>
>   Please indent with tabs, not spaces. Also, doesn't this code generate
> warning (code before declarations)?
>
>
>         unsigned long lsize = CONFIG_SYS_CACHELINE_SIZE;
>>        unsigned long addr = start_addr&  ~(lsize - 1);
>>        unsigned long aend = (start_addr + size - 1)&  ~(lsize - 1);
>>
>
> WBR, Sergei
>