[U-Boot] [PATCH] Revert "common/memsize.c: Simplify RAM size detection"

[Hans de Goede]

Hi,

On 10-02-16 07:11, Eddy Petrișor wrote:
> Hi Hans,
>
> I sent a fixup patch yesterday (I managed somehow to send an outdated
> patch),

Ah I did not notice that one.

> did you try the fixup patch?

I just did try it, same results as Hannes the hang is gone, but now
the RAM size is misdedetected (it detects 2 GiB on a 1 GiB board).

It seems this code was as it was for a reason and that a revert
of your simplification is probably the best solution.

Regards,

Hans




>
> http://lists.denx.de/pipermail/u-boot/2016-February/245080.html
> Pe 9 feb. 2016 11:38 p.m., "Hans de Goede" <hdegoede at redhat.com> a scris:
>
>> This commit breaks bootup on sunxi boards, the get stuck
>> when running the main u-boot binary at:
>>
>> CPU:   Allwinner H3 (SUN8I)
>> I2C:   ready
>> DRAM:
>>
>> This reverts commit 8e7cba048baae68ee0916a8f52b4304277328d5e.
>>
>> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
>> ---
>>   common/memsize.c | 47 ++++++++++++++++++++++++++---------------------
>>   1 file changed, 26 insertions(+), 21 deletions(-)
>>
>> diff --git a/common/memsize.c b/common/memsize.c
>> index 5c0d279..0fb9ba5 100644
>> --- a/common/memsize.c
>> +++ b/common/memsize.c
>> @@ -33,28 +33,38 @@ long get_ram_size(long *base, long maxsize)
>>          long           size;
>>          int            i = 0;
>>
>> -       for (cnt = (maxsize / sizeof(long)) >> 1; cnt >= 0; cnt >>= 1) {
>> +       for (cnt = (maxsize / sizeof(long)) >> 1; cnt > 0; cnt >>= 1) {
>>                  addr = base + cnt;      /* pointer arith! */
>>                  sync();
>> -               save[i] = *addr;
>> +               save[i++] = *addr;
>>                  sync();
>> -               if (cnt) {
>> -                       i++;
>> -                       *addr = ~cnt;
>> -               } else {
>> -                       *addr = 0;
>> -               }
>> +               *addr = ~cnt;
>>          }
>>
>> +       addr = base;
>> +       sync();
>> +       save[i] = *addr;
>> +       sync();
>> +       *addr = 0;
>> +
>>          sync();
>> -       cnt = 0;
>> -       do {
>> +       if ((val = *addr) != 0) {
>> +               /* Restore the original data before leaving the function.
>> */
>> +               sync();
>> +               *addr = save[i];
>> +               for (cnt = 1; cnt < maxsize / sizeof(long); cnt <<= 1) {
>> +                       addr  = base + cnt;
>> +                       sync();
>> +                       *addr = save[--i];
>> +               }
>> +               return (0);
>> +       }
>> +
>> +       for (cnt = 1; cnt < maxsize / sizeof(long); cnt <<= 1) {
>>                  addr = base + cnt;      /* pointer arith! */
>>                  val = *addr;
>> -               *addr = save[i--];
>> -               sync();
>> -               if (((cnt == 0) && (val != 0)) ||
>> -                   ((cnt != 0) && (val != ~cnt))) {
>> +               *addr = save[--i];
>> +               if (val != ~cnt) {
>>                          size = cnt * sizeof(long);
>>                          /*
>>                           * Restore the original data
>> @@ -64,16 +74,11 @@ long get_ram_size(long *base, long maxsize)
>>                               cnt < maxsize / sizeof(long);
>>                               cnt <<= 1) {
>>                                  addr  = base + cnt;
>> -                               *addr = save[i--];
>> +                               *addr = save[--i];
>>                          }
>>                          return (size);
>>                  }
>> -
>> -               if (cnt)
>> -                       cnt = cnt << 1;
>> -               else
>> -                       cnt = 1;
>> -       } while (cnt < maxsize / sizeof(long));
>> +       }
>>
>>          return (maxsize);
>>   }
>> --
>> 2.5.0
>>
>>
>