net: ipa: rearrange functions for similarity

Both aggr_time_limit_encode() and hol_block_timer_encode() figure
out how to encode a millisecond time value so it can be programmed
into a register.  Rearranging them a bit can make their similarity
more obvious, with both taking essentially the same form.

To do this:
  - Return 0 immediately in aggr_time_limit_encode() if the
    microseconds value supplied is zero.
  - Reverse the test at top of aggr_time_limit_encode(), so we
    compute and return the Qtime value in the "true" block,
    and compute the result the old way otherwise.
  - Open-code (and eliminate) hol_block_timer_qtime_encode() at the
    top of hol_block_timer_encode() in the case we use Qtimer.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c
index 7d91b42..6db62b6 100644 (file)
--- a/drivers/net/ipa/ipa_endpoint.c
+++ b/drivers/net/ipa/ipa_endpoint.c
@@ -752,34 +752,38 @@ static int ipa_qtime_val(u32 microseconds, u32 max)
 /* Encode the aggregation timer limit (microseconds) based on IPA version */
 static u32 aggr_time_limit_encode(enum ipa_version version, u32 microseconds)
 {
-       u32 gran_sel;
        u32 fmask;
        u32 val;
-       int ret;
 
-       if (version < IPA_VERSION_4_5) {
-               /* We set aggregation granularity in ipa_hardware_config() */
-               fmask = aggr_time_limit_fmask(true);
-               val = DIV_ROUND_CLOSEST(microseconds, IPA_AGGR_GRANULARITY);
-               WARN(val > field_max(fmask),
-                    "aggr_time_limit too large (%u > %u usec)\n",
-                    val, field_max(fmask) * IPA_AGGR_GRANULARITY);
-
-               return u32_encode_bits(val, fmask);
-       }
+       if (!microseconds)
+               return 0;       /* Nothing to compute if time limit is 0 */
+
+       if (version >= IPA_VERSION_4_5) {
+               u32 gran_sel;
+               int ret;
+
+               /* Compute the Qtime limit value to use */
+               fmask = aggr_time_limit_fmask(false);
+               ret = ipa_qtime_val(microseconds, field_max(fmask));
+               if (ret < 0) {
+                       val = -ret;
+                       gran_sel = AGGR_GRAN_SEL_FMASK;
+               } else {
+                       val = ret;
+                       gran_sel = 0;
+               }
 
-       /* Compute the Qtime limit value to use */
-       fmask = aggr_time_limit_fmask(false);
-       ret = ipa_qtime_val(microseconds, field_max(fmask));
-       if (ret < 0) {
-               val = -ret;
-               gran_sel = AGGR_GRAN_SEL_FMASK;
-       } else {
-               val = ret;
-               gran_sel = 0;
+               return gran_sel | u32_encode_bits(val, fmask);
        }
 
-       return gran_sel | u32_encode_bits(val, fmask);
+       /* We set aggregation granularity in ipa_hardware_config() */
+       fmask = aggr_time_limit_fmask(true);
+       val = DIV_ROUND_CLOSEST(microseconds, IPA_AGGR_GRANULARITY);
+       WARN(val > field_max(fmask),
+            "aggr_time_limit too large (%u > %u usec)\n",
+            val, field_max(fmask) * IPA_AGGR_GRANULARITY);
+
+       return u32_encode_bits(val, fmask);
 }
 
 static u32 aggr_sw_eof_active_encoded(enum ipa_version version, bool enabled)
@@ -837,28 +841,6 @@ static void ipa_endpoint_init_aggr(struct ipa_endpoint *endpoint)
        iowrite32(val, endpoint->ipa->reg_virt + offset);
 }
 
-/* Return the Qtime-based head-of-line blocking timer value that
- * represents the given number of microseconds.  The result
- * includes both the timer value and the selected timer granularity.
- */
-static u32 hol_block_timer_qtime_encode(struct ipa *ipa, u32 microseconds)
-{
-       u32 gran_sel;
-       u32 val;
-       int ret;
-
-       ret = ipa_qtime_val(microseconds, field_max(TIME_LIMIT_FMASK));
-       if (ret < 0) {
-               val = -ret;
-               gran_sel = GRAN_SEL_FMASK;
-       } else {
-               val = ret;
-               gran_sel = 0;
-       }
-
-       return gran_sel | u32_encode_bits(val, TIME_LIMIT_FMASK);
-}
-
 /* The head-of-line blocking timer is defined as a tick count.  For
  * IPA version 4.5 the tick count is based on the Qtimer, which is
  * derived from the 19.2 MHz SoC XO clock.  For older IPA versions
@@ -879,8 +861,22 @@ static u32 hol_block_timer_encode(struct ipa *ipa, u32 microseconds)
        if (!microseconds)
                return 0;       /* Nothing to compute if timer period is 0 */
 
-       if (ipa->version >= IPA_VERSION_4_5)
-               return hol_block_timer_qtime_encode(ipa, microseconds);
+       if (ipa->version >= IPA_VERSION_4_5) {
+               u32 gran_sel;
+               int ret;
+
+               /* Compute the Qtime limit value to use */
+               ret = ipa_qtime_val(microseconds, field_max(TIME_LIMIT_FMASK));
+               if (ret < 0) {
+                       val = -ret;
+                       gran_sel = GRAN_SEL_FMASK;
+               } else {
+                       val = ret;
+                       gran_sel = 0;
+               }
+
+               return gran_sel | u32_encode_bits(val, TIME_LIMIT_FMASK);
+       }
 
        /* Use 64 bit arithmetic to avoid overflow... */
        rate = ipa_core_clock_rate(ipa);