On 1/29/2021 1:04 PM, Willem de Bruijn wrote:
> On Fri, Jan 29, 2021 at 4:01 PM Willem de Bruijn
> <willemdebruijn.ker...@gmail.com> wrote:
>>
>> On Thu, Jan 28, 2021 at 7:46 PM Tony Nguyen <anthony.l.ngu...@intel.com>
>> wrote:
>>>
>>> From: Jacob Keller <jacob.e.kel...@intel.com>
>>>
>>> The ice flash contains two copies of each of the NVM, Option ROM, and
>>> Netlist modules. Each bank has a pointer word and a size word. In order
>>> to correctly read from the active flash bank, the driver must calculate
>>> the offset manually.
>>>
>>> During NVM initialization, read the Shadow RAM control word and
>>> determine which bank is active for each NVM module. Additionally, cache
>>> the size and pointer values for use in calculating the correct offset.
>>>
>>> Signed-off-by: Jacob Keller <jacob.e.kel...@intel.com>
>>> Tested-by: Tony Brelinski <tonyx.brelin...@intel.com>
>>> Signed-off-by: Tony Nguyen <anthony.l.ngu...@intel.com>
>>> ---
>>> drivers/net/ethernet/intel/ice/ice_nvm.c | 151 ++++++++++++++++++++++
>>> drivers/net/ethernet/intel/ice/ice_type.h | 37 ++++++
>>> 2 files changed, 188 insertions(+)
>>>
>>> diff --git a/drivers/net/ethernet/intel/ice/ice_nvm.c
>>> b/drivers/net/ethernet/intel/ice/ice_nvm.c
>>> index b0f0b4fc266b..308344045397 100644
>>> --- a/drivers/net/ethernet/intel/ice/ice_nvm.c
>>> +++ b/drivers/net/ethernet/intel/ice/ice_nvm.c
>>> @@ -603,6 +603,151 @@ static enum ice_status ice_discover_flash_size(struct
>>> ice_hw *hw)
>>> return status;
>>> }
>>>
>>> +/**
>>> + * ice_read_sr_pointer - Read the value of a Shadow RAM pointer word
>>> + * @hw: pointer to the HW structure
>>> + * @offset: the word offset of the Shadow RAM word to read
>>> + * @pointer: pointer value read from Shadow RAM
>>> + *
>>> + * Read the given Shadow RAM word, and convert it to a pointer value
>>> specified
>>> + * in bytes. This function assumes the specified offset is a valid pointer
>>> + * word.
>>> + *
>>> + * Each pointer word specifies whether it is stored in word size or 4KB
>>> + * sector size by using the highest bit. The reported pointer value will
>>> be in
>>> + * bytes, intended for flat NVM reads.
>>> + */
>>> +static enum ice_status
>>> +ice_read_sr_pointer(struct ice_hw *hw, u16 offset, u32 *pointer)
>>> +{
>>> + enum ice_status status;
>>> + u16 value;
>>> +
>>> + status = ice_read_sr_word(hw, offset, &value);
>>> + if (status)
>>> + return status;
>>> +
>>> + /* Determine if the pointer is in 4KB or word units */
>>> + if (value & ICE_SR_NVM_PTR_4KB_UNITS)
>>> + *pointer = (value & ~ICE_SR_NVM_PTR_4KB_UNITS) * 4 * 1024;
>>> + else
>>> + *pointer = value * 2;
>>
>> Should this be << 2, for 4B words?
>
> Never mind, sorry. I gather from patch 3 that wordsize is 16b.
>
Ah, yes that could have been explained a bit better. In this context, a
word is indeed 2 bytes.
Perhaps we could have used "<< 1" and "<< 12" or similar instead of the
multiplication, but I felt this was a bit more clear.
Thanks,
Jake
