[PATCH net-next 1/3] net: ipa: rework ipa_aggr_granularity_val()
From: Alex Elder <hidden>
Date: 2020-06-29 21:55:56
Also in:
lkml
Subsystem:
networking drivers, qcom ipa driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Alex Elder, Linus Torvalds
The timer used for aggregation makes use of an internal 32 KHz clock. The granularity of the timer is programmed by a field whose value is computed by ipa_aggr_granularity_val(). Redefine the way that value is computed by using a new TIMER_FREQUENCY constant representing the underlying clock frequency. Add two BUILD_BUG_ON() calls to ensure the value used is valid. Signed-off-by: Alex Elder <redacted> --- drivers/net/ipa/ipa_main.c | 5 +++++ drivers/net/ipa/ipa_reg.h | 17 ++++++++--------- 2 files changed, 13 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ipa/ipa_main.c b/drivers/net/ipa/ipa_main.c
index 76d5108b8403..27a869df3a4b 100644
--- a/drivers/net/ipa/ipa_main.c
+++ b/drivers/net/ipa/ipa_main.c@@ -674,6 +674,11 @@ static void ipa_validate_build(void) /* This is used as a divisor */ BUILD_BUG_ON(!IPA_AGGR_GRANULARITY); + + /* Aggregation granularity value can't be 0, and must fit */ + BUILD_BUG_ON(!ipa_aggr_granularity_val(IPA_AGGR_GRANULARITY)); + BUILD_BUG_ON(ipa_aggr_granularity_val(IPA_AGGR_GRANULARITY) > + field_max(AGGR_GRANULARITY)); #endif /* IPA_VALIDATE */ }
diff --git a/drivers/net/ipa/ipa_reg.h b/drivers/net/ipa/ipa_reg.h
index 0a688d8c1d7c..7ae8015798ae 100644
--- a/drivers/net/ipa/ipa_reg.h
+++ b/drivers/net/ipa/ipa_reg.h@@ -190,24 +190,23 @@ static inline u32 ipa_reg_bcr_val(enum ipa_version version) return 0x00000000; } - #define IPA_REG_LOCAL_PKT_PROC_CNTXT_BASE_OFFSET 0x000001e8 #define IPA_REG_AGGR_FORCE_CLOSE_OFFSET 0x000001ec /* ipa->available defines the valid bits in the AGGR_FORCE_CLOSE register */ +/* The internal inactivity timer clock is used for the aggregation timer */ +#define TIMER_FREQUENCY 32000 /* 32 KHz inactivity timer clock */ + #define IPA_REG_COUNTER_CFG_OFFSET 0x000001f0 #define AGGR_GRANULARITY GENMASK(8, 4) -/* Compute the value to use in the AGGR_GRANULARITY field representing - * the given number of microseconds (up to 1 millisecond). - * x = (32 * usec) / 1000 - 1 +/* Compute the value to use in the AGGR_GRANULARITY field representing the + * given number of microseconds. The value is one less than the number of + * timer ticks in the requested period. Zero not a valid granularity value. */ -static inline u32 ipa_aggr_granularity_val(u32 microseconds) +static inline u32 ipa_aggr_granularity_val(u32 usec) { - /* assert(microseconds >= 16); (?) */ - /* assert(microseconds <= 1015); */ - - return DIV_ROUND_CLOSEST(32 * microseconds, 1000) - 1; + return DIV_ROUND_CLOSEST(usec * TIMER_FREQUENCY, USEC_PER_SEC) - 1; } #define IPA_REG_TX_CFG_OFFSET 0x000001fc
--
2.25.1