[PATCH 1/1][SRU][OEM-5.10] UBUNTU: SAUCE: platform/x86: intel_pmc: Ignore GBE LTR on Tiger Lake platforms

[Timo Aaltonen]

On 15.3.2021 17.58, Andrea Righi wrote:
> On Mon, Mar 15, 2021 at 02:53:28PM +0800, AceLan Kao wrote:
>> From: "David E. Box" <david.e.box at linux.intel.com>
>>
>> BugLink: https://bugs.launchpad.net/bugs/1919116
>>
>> Due to a HW limitation, the Latency Tolerance Reporting (LTR) value
>> programmed in the Tiger Lake GBE controller is not large enough to allow
>> the platform to enter Package C10, which in turn prevents the platform from
>> achieving its low power target during suspend-to-idle.  Ignore the GBE LTR
>> value on Tiger Lake. LTR ignore functionality is currently performed solely
>> by a debugfs write call. Split out the LTR code into its own function that
>> can be called by both the debugfs writer and by this work around.
>>
>> Signed-off-by: David E. Box <david.e.box at linux.intel.com>
>> Reviewed-by: Sasha Neftin <sasha.neftin at intel.com>
>> Cc: intel-wired-lan at lists.osuosl.org
>> (cherry picked from
>> https://patchwork.kernel.org/project/platform-driver-x86/patch/20210305190608.1834164-1-david.e.box@linux.intel.com/)
>> Signed-off-by: Chia-Lin Kao (AceLan) <acelan.kao at canonical.com>
>> ---
>>   drivers/platform/x86/intel_pmc_core.c | 55 ++++++++++++++++++++-------
>>   1 file changed, 42 insertions(+), 13 deletions(-)
> 
> ...
>> +	/*
>> +	 * On TGL, due to a hardware limitation, the GBE LTR blocks PC10 when
>> +	 * a cable is attached. Tell the PMC to ignore it.
>> +	 */
>> +	if (pmcdev->map == &tgl_reg_map) {
> 
> Someone on the list suggested: if (pmcdev->map >= &tgl_reg_map)
> 
> Should we include also this change?
> 

this was considered to be a bad idea


-- 
t