[PATCH v4 06/12] arm: mvebu: clearfog: Add option for 2.5 Gbps SFP

[Joel Johnson]

On 2020-01-26 22:29, Baruch Siach wrote:
> Hi Joel,
> 
> On Mon, Jan 27 2020, Joel Johnson wrote:
>> While newer Linux kernels provide autoconfiguration of SFP, provide
>> an option for setting in U-Boot Kconfig for use prior to booting.
>> 
>> Signed-off-by: Joel Johnson <mrjoel at lixil.net>
>> 
>> ---
>> 
>> v2 changes:
>>   - fixed help indentation
>> v3 changes:
>>   - none
>> v4 changes:
>>   - adjust static SerDes configuration at runtime instead of #ifdef
>> 
>> ---
>>  board/solidrun/clearfog/Kconfig    | 7 +++++++
>>  board/solidrun/clearfog/clearfog.c | 3 +++
>>  2 files changed, 10 insertions(+)
>> 
>> diff --git a/board/solidrun/clearfog/Kconfig 
>> b/board/solidrun/clearfog/Kconfig
>> index 936d5918f8..c910e17093 100644
>> --- a/board/solidrun/clearfog/Kconfig
>> +++ b/board/solidrun/clearfog/Kconfig
>> @@ -15,4 +15,11 @@ config TARGET_CLEARFOG_BASE
>>  	  detection via additional EEPROM hardware. This option enables 
>> selecting
>>  	  the Base variant for older hardware revisions.
>> 
>> +config CLEARFOG_SFP_25GB
>> +	bool "Enable 2.5 Gbps mode for SFP"
>> +	help
>> +	  Set the SFP module connection to support 2.5 Gbps transfer speed 
>> for the
>> +	  SGMII connection (requires a supporting SFP). By default, transfer 
>> speed
>> +	  of 1.25 Gbps is used, suitable for a more common 1 Gbps SFP 
>> module.
>> +
>>  endmenu
>> diff --git a/board/solidrun/clearfog/clearfog.c 
>> b/board/solidrun/clearfog/clearfog.c
>> index 4019e37016..6c5b9a784f 100644
>> --- a/board/solidrun/clearfog/clearfog.c
>> +++ b/board/solidrun/clearfog/clearfog.c
>> @@ -59,6 +59,9 @@ void config_static_serdes_map(void)
>>  		board_serdes_map[4].serdes_speed = SERDES_SPEED_5_GBPS;
>>  		board_serdes_map[4].serdes_mode = SERDES_DEFAULT_MODE;
>>  	}
>> +
>> +	if (IS_ENABLED(CONFIG_CLEARFOG_SFP_25GB))
>> +		board_serdes_map[5].serdes_speed = SERDES_SPEED_3_125_GBPS;
> 
> config_static_serdes_map() is not called only when TLV EEPROM is
> present. So CONFIG_CLEARFOG_SFP_25GB has no effect in that case. This
> code should move to hws_board_topology_load() to avoid that.

Yeah, that's what I was trying to ask with the question below embedded 
in patch 4.

     "Note that this approach *does not* currently provide any mechanism
     for EEPROM detected boards to have their SFP speed changed or switch
     between PCIE/SATA signalling. I'm assuming that will be done based 
on
     hardware detection, but confirmation/acceptance in review would be
     appreciated so it can be revisited if needed.

After sending the series and thinking about it more, I didn't see any 
other mechanism by which the configuration would be changed. The 
question was really to confirm what I had inferred from code, namely 
that Pro/Base boards even with EEPROM would still have to have a U-Boot 
built with custom options in order to change the PCIe/SATA or SFP 
options. I would like to confirm with you that is desired and expected 
even in the cases of EEPROM supporting units. If that's the case, I'll 
rework the location of setting, along with updating the help text for 
those options. Pending your confirmation, I plan to get rid of the 
separate config_static_serdes_map function and fold it back in, with the 
SATA and SFP options coming before the board runtime detection 
configuration.

Joel