On 05/29/2015 09:09 PM, Arend van Spriel wrote:
> On 05/29/15 20:44, Hauke Mehrtens wrote:
>>
>>
>> On 05/29/2015 08:26 PM, Arend van Spriel wrote:
>>> On 05/29/15 18:57, Arend van Spriel wrote:
>>>> On 05/29/15 16:59, Hauke Mehrtens wrote:
>>>>>
>>>>>
>>>>> On 05/21/2015 03:27 PM, Arend van Spriel wrote:
>>>>>> From: Hante Meuleman<meuleman@xxxxxxxxxxxx>
>>>>>>
>>>>>> Host platforms such as routers supported by OpenWrt can
>>>>>> support NVRAM reading directly from internal NVRAM store.
>>>>>> The brcmfmac for one requires the complete nvram contents
>>>>>> to select what needs to be sent to wireless device.
>>>>>>
>>>>>> Reviewed-by: Arend Van Spriel<arend@xxxxxxxxxxxx>
>>>>>> Reviewed-by: Franky (Zhenhui) Lin<frankyl@xxxxxxxxxxxx>
>>>>>> Reviewed-by: Pieter-Paul Giesberts<pieterpg@xxxxxxxxxxxx>
>>>>>> Reviewed-by: Daniel (Deognyoun) Kim<dekim@xxxxxxxxxxxx>
>>>>>> Signed-off-by: Hante Meuleman<meuleman@xxxxxxxxxxxx>
>>>>>> Signed-off-by: Arend van Spriel<arend@xxxxxxxxxxxx>
>>>>>> ---
>>>>>> Change log:
>>>>>> -----------
>>>>>> V2: - correct header length for nvram_find_and_copy().
>>>>>> - get rid of 'NVRAM_SPACE - 2' magic.
>>>>>> ---
>>>>>> arch/mips/bcm47xx/nvram.c | 61
>>>>>> ++++++++++++++++++++++++++++++++-----------
>>>>>> include/linux/bcm47xx_nvram.h | 15 +++++++++++
>>>>>> 2 files changed, 61 insertions(+), 15 deletions(-)
>>>>>>
>>>>>> diff --git a/arch/mips/bcm47xx/nvram.c b/arch/mips/bcm47xx/nvram.c
>>>>>> index 95d028c..f4f62d3 100644
>>>>>> --- a/arch/mips/bcm47xx/nvram.c
>>>>>> +++ b/arch/mips/bcm47xx/nvram.c
>>>>>> @@ -94,17 +94,22 @@ static int nvram_find_and_copy(void __iomem
>>>>>> *iobase, u32 lim)
>>>>>> return -ENXIO;
>>>>>>
>>>>>> found:
>>>>>> - if (header->len> size)
>>>>>> - pr_err("The nvram size accoridng to the header seems to be bigger
>>>>>> than the partition on flash\n");
>>>>>> - if (header->len> NVRAM_SPACE)
>>>>>> - pr_err("nvram on flash (%i bytes) is bigger than the reserved space
>>>>>> in memory, will just copy the first %i bytes\n",
>>>>>> - header->len, NVRAM_SPACE - 1);
>>>>>> -
>>>>>> src = (u32 *)header;
>>>>>> dst = (u32 *)nvram_buf;
>>>>>> for (i = 0; i< sizeof(struct nvram_header); i += 4)
>>>>>> *dst++ = __raw_readl(src++);
>>>>>> - for (; i< header->len&& i< NVRAM_SPACE&& i< size; i += 4)
>>>>>> + header = (struct nvram_header *)nvram_buf;
>>>>>> + if (header->len> size) {
>>>>>> + pr_err("The nvram size according to the header seems to be bigger
>>>>>> than the partition on flash\n");
>>>>>
>>>>> Thanks for fixing a typo. ;-)
>>>>>
>>>>>> + header->len = size;
>>>>>
>>>>> I haven't seen this error case, I just added it to be save.
>>>>
>>>> It does seem an unlikely error case. At least it would probably been
>>>> noticed during production writing the content to flash.
>>>>
>>>>>> + }
>>>>>> + if (header->len>= NVRAM_SPACE) {
>>>>>> + pr_err("nvram on flash (%i bytes) is bigger than the reserved space
>>>>>> in memory, will just copy the first %i bytes\n",
>>>>>> + header->len, NVRAM_SPACE - 1);
>>>>>> + header->len = NVRAM_SPACE - 1;
>>>>>> + }
>>>>>
>>>>> After fixing the length the header is better, but it also contains a
>>>>> CRC, which is still wrong, but we ignore it and I do not think we have
>>>>> to check.
>>>>>
>>>>> I still think that the best approach would be to remove the nvram
>>>>> header
>>>>> and add a extra variable storing the actual size of the nvram buf. I
>>>>> also think this would make some of this code easier.
>>>>
>>>> Let's do that then.
>>>
>>> Hi Hauke,
>>>
>>> Forgot to ask. What is the reason for using the fixed nvram space. Could
>>> we allocate it using vzalloc()?
>>
>> On mips this is needed very early in the boot process at least for the
>> older SoCs using ssb. In this state we can not allocate memory.
>
> I suspected that, but wanted to be sure.
>
We tried to use some kind of allocation mechanism, because the nvram
partitions of different devices have different sizes. The older devices
mostly have small partitions and the newer ons bigger. With the arm SoCs
we do not need the nvram so early and can use some normal allocation
mechanism.
Hauke
