net: ipa: use Qtime for IPA v4.5 aggregation time limit

Change aggr_time_limit_encoded() to properly calculate the
aggregation time limit to use for IPA v4.5.

Older IPA versions program the AGGR_GRANULARITY field of the
of the COUNTER_CFG register to set the granularity of the
aggregation timer, which we configure to be 500 microseconds.

Instead, IPA v4.5 selects between two possible granularity values
derived from the 19.2 MHz Qtime clock.  These granularities are
100 microseconds or 1 millisecond per tick.  We use the smaller
granularity if possible, unless the desired period is too large
to be specified that way.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Alex Elder 2020-11-30 17:37:11 -06:00 committed by Jakub Kicinski
parent 3642641102
commit 1954704136
1 changed files with 29 additions and 5 deletions

View File

@ -638,14 +638,38 @@ static u32 aggr_byte_limit_encoded(enum ipa_version version, u32 limit)
return u32_encode_bits(limit, aggr_byte_limit_fmask(false));
}
/* Encode the aggregation timer limit (microseconds) based on IPA version */
static u32 aggr_time_limit_encoded(enum ipa_version version, u32 limit)
{
/* Convert limit (microseconds) to aggregation timer ticks */
limit = DIV_ROUND_CLOSEST(limit, IPA_AGGR_GRANULARITY);
if (version < IPA_VERSION_4_5)
return u32_encode_bits(limit, aggr_time_limit_fmask(true));
u32 gran_sel;
u32 fmask;
u32 val;
return u32_encode_bits(limit, aggr_time_limit_fmask(false));
if (version < IPA_VERSION_4_5) {
/* We set aggregation granularity in ipa_hardware_config() */
limit = DIV_ROUND_CLOSEST(limit, IPA_AGGR_GRANULARITY);
return u32_encode_bits(limit, aggr_time_limit_fmask(true));
}
/* IPA v4.5 expresses the time limit using Qtime. The AP has
* pulse generators 0 and 1 available, which were configured
* in ipa_qtime_config() to have granularity 100 usec and
* 1 msec, respectively. Use pulse generator 0 if possible,
* otherwise fall back to pulse generator 1.
*/
fmask = aggr_time_limit_fmask(false);
val = DIV_ROUND_CLOSEST(limit, 100);
if (val > field_max(fmask)) {
/* Have to use pulse generator 1 (millisecond granularity) */
gran_sel = AGGR_GRAN_SEL_FMASK;
val = DIV_ROUND_CLOSEST(limit, 1000);
} else {
/* We can use pulse generator 0 (100 usec granularity) */
gran_sel = 0;
}
return gran_sel | u32_encode_bits(val, fmask);
}
static u32 aggr_sw_eof_active_encoded(enum ipa_version version, bool enabled)