[U-Boot] [PATCH v2] fdt: fix setting MAC addresses for multiple interfaces

[Lev Iserovich <Lev.Iserovich@deshawresearch.com>]

Hi,

Updated with C-style comments:

For multiple ethernet interfaces the FDT offset of '/aliases' will 
change as we
are adding MAC addresses to the FDT.
Therefore only the first interface ('ethernet0') will get properly 
updated in
the FDT, with the rest getting FDT errors when we try to set their MAC 
address.

Signed-off-by: Lev Iserovich<iserovil@deshawresearch.com>
---

Changes in v2:
    - Rebase on u-boot-net patches:
      http://patchwork.ozlabs.org/patch/539373/
      http://patchwork.ozlabs.org/patch/539374/
    - Recompute offset based on property index
    - C-style comments

---

  common/fdt_support.c | 21 ++++++++++++++-------
  1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/common/fdt_support.c b/common/fdt_support.c
index 48faba9..713d2a4 100644
--- a/common/fdt_support.c
+++ b/common/fdt_support.c
@@ -481,23 +481,30 @@ int fdt_fixup_memory(void *blob, u64 start, u64 size)

  void fdt_fixup_ethernet(void *fdt)
  {
-       int node, i, j;
+       int i, j, prop;
         char *tmp, *end;
         char mac[16];
         const char *path;
         unsigned char mac_addr[6];
         int offset;

-       node = fdt_path_offset(fdt, "/aliases");
-       if (node < 0)
+       if (fdt_path_offset(fdt, "/aliases") < 0)
                 return;
-
-       for (offset = fdt_first_property_offset(fdt, node);
-            offset > 0;
-            offset = fdt_next_property_offset(fdt, offset)) {
+
+       /* Cycle through all aliases */
+       for (prop = 0; ; prop++) {
                 const char *name;
                 int len = strlen("ethernet");

+               /* FDT might have been edited, recompute the offset */
+               offset = fdt_first_property_offset(fdt, 
fdt_path_offset(fdt, "/aliases"));
+               /* Select property number 'prop' */
+               for (i = 0; i < prop; i++) {
+                       offset = fdt_next_property_offset(fdt, offset);
+               }
+               if (offset < 0)
+                       break;
+
                 path = fdt_getprop_by_offset(fdt, offset, &name, NULL);
                 if (!strncmp(name, "ethernet", len)) {
                         i = trailing_strtol(name);


On 04/26/2016 08:06 PM, Bin Meng wrote:
> Hi Lev,
>
> On Fri, Jan 8, 2016 at 7:04 AM, Lev Iserovich
> <Lev.Iserovich@deshawresearch.com> wrote:
>> For multiple ethernet interfaces the FDT offset of '/aliases' will change as
>> we
>> are adding MAC addresses to the FDT.
>> Therefore only the first interface ('ethernet0') will get properly updated
>> in
>> the FDT, with the rest getting FDT errors when we try to set their MAC
>> address.
>>
>> Signed-off-by: Lev Iserovich<iserovil@deshawresearch.com>
>> ---
>>
>> Changes in v2:
>>     - Rebase on u-boot-net patches:
>>       http://patchwork.ozlabs.org/patch/539373/
>>       http://patchwork.ozlabs.org/patch/539374/
>>     - Recompute offset based on property index
>>
>> ---
>>
>>   common/fdt_support.c | 21 ++++++++++++++-------
>>   1 file changed, 14 insertions(+), 7 deletions(-)
>>
>> diff --git a/common/fdt_support.c b/common/fdt_support.c
>> index 48faba9..713d2a4 100644
>> --- a/common/fdt_support.c
>> +++ b/common/fdt_support.c
>> @@ -481,23 +481,30 @@ int fdt_fixup_memory(void *blob, u64 start, u64 size)
>>
>>   void fdt_fixup_ethernet(void *fdt)
>>   {
>> -       int node, i, j;
>> +       int i, j, prop;
>>          char *tmp, *end;
>>          char mac[16];
>>          const char *path;
>>          unsigned char mac_addr[6];
>>          int offset;
>>
>> -       node = fdt_path_offset(fdt, "/aliases");
>> -       if (node < 0)
>> +       if (fdt_path_offset(fdt, "/aliases") < 0)
>>                  return;
>> -
>> -       for (offset = fdt_first_property_offset(fdt, node);
>> -            offset > 0;
>> -            offset = fdt_next_property_offset(fdt, offset)) {
>> +
>> +       // Cycle through all aliases
> Please do not use C++ comment style.
>
>> +       for (prop = 0; ; prop++) {
>>                  const char *name;
>>                  int len = strlen("ethernet");
>>
>> +               // FDT might have been edited, recompute the offset
> ditto.
>
>> +               offset = fdt_first_property_offset(fdt, fdt_path_offset(fdt,
>> "/aliases"));
>> +               // Select property number 'prop'
> ditto.
>
>> +               for (i = 0; i < prop; i++) {
>> +                       offset = fdt_next_property_offset(fdt, offset);
>> +               }
>> +               if (offset < 0)
>> +                       break;
>> +
>>                  path = fdt_getprop_by_offset(fdt, offset, &name, NULL);
>>                  if (!strncmp(name, "ethernet", len)) {
>>                          i = trailing_strtol(name);
>>
> Regards,
> Bin