Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1340539

[PATCH 09/13] arm-cci: Add helper to enable PMU without synchornising counters

From Suzuki K Poulose <suzuki.poulose@arm.com>
Newsgroups linux.kernel
Subject [PATCH 09/13] arm-cci: Add helper to enable PMU without synchornising counters
Date 2016-02-23 12:00 +0100
Message-ID <r5iRe-45N-39@gated-at.bofh.it> (permalink)
References <r5iRc-45N-3@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On CCI-500 writing to a counter requires turning the PMU on. So,
synchronising the counter state should not be performed for such special cases,
while turning the PMU on. This patch adds a helper, __cci_pmu_enable_nosync(),
without flushing the counter states.

Cc: Punit Agrawal <punit.agrawal@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
 drivers/bus/arm-cci.c |   15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/bus/arm-cci.c b/drivers/bus/arm-cci.c
index 7ce7da0..bcc4c59 100644
--- a/drivers/bus/arm-cci.c
+++ b/drivers/bus/arm-cci.c
@@ -640,18 +640,23 @@ void cci_pmu_sync_counters(struct cci_pmu *cci_pmu)
 }
 
 /* Should be called with cci_pmu->hw_events->pmu_lock held */
-static void __cci_pmu_enable(struct cci_pmu *cci_pmu)
+static void __cci_pmu_enable_nosync(struct cci_pmu *cci_pmu)
 {
 	u32 val;
 
-	cci_pmu_sync_counters(cci_pmu);
-
 	/* Enable all the PMU counters. */
 	val = readl_relaxed(cci_ctrl_base + CCI_PMCR) | CCI_PMCR_CEN;
 	writel(val, cci_ctrl_base + CCI_PMCR);
 }
 
 /* Should be called with cci_pmu->hw_events->pmu_lock held */
+static void __cci_pmu_enable_sync(struct cci_pmu *cci_pmu)
+{
+	cci_pmu_sync_counters(cci_pmu);
+	__cci_pmu_enable_nosync(cci_pmu);
+}
+
+/* Should be called with cci_pmu->hw_events->pmu_lock held */
 static void __cci_pmu_disable(void)
 {
 	u32 val;
@@ -960,7 +965,7 @@ static irqreturn_t pmu_handle_irq(int irq_num, void *dev)
 	}
 
 	/* Enable the PMU and sync possibly overflowed counters */
-	__cci_pmu_enable(cci_pmu);
+	__cci_pmu_enable_sync(cci_pmu);
 	raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
 
 	return IRQ_RETVAL(handled);
@@ -1004,7 +1009,7 @@ static void cci_pmu_enable(struct pmu *pmu)
 		return;
 
 	raw_spin_lock_irqsave(&hw_events->pmu_lock, flags);
-	__cci_pmu_enable(cci_pmu);
+	__cci_pmu_enable_sync(cci_pmu);
 	raw_spin_unlock_irqrestore(&hw_events->pmu_lock, flags);
 
 }
-- 
1.7.9.5

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH 00/13] arm-cci: PMU driver updates for 4.6 Suzuki K Poulose <suzuki.poulose@arm.com> - 2016-02-23 12:00 +0100
  [PATCH 05/13] arm-cci: Delay PMU counter writes to pmu::pmu_enable Suzuki K Poulose <suzuki.poulose@arm.com> - 2016-02-23 12:00 +0100
  [PATCH 07/13] arm-cci: Get the status of a counter Suzuki K Poulose <suzuki.poulose@arm.com> - 2016-02-23 12:00 +0100
  [PATCH 03/13] arm-cci: Group writes to counter Suzuki K Poulose <suzuki.poulose@arm.com> - 2016-02-23 12:00 +0100
  [PATCH 06/13] arm-cci: write_counter: Remove redundant check Suzuki K Poulose <suzuki.poulose@arm.com> - 2016-02-23 12:00 +0100
  [PATCH 09/13] arm-cci: Add helper to enable PMU without synchornising counters Suzuki K Poulose <suzuki.poulose@arm.com> - 2016-02-23 12:00 +0100
  [PATCH 08/13] arm-cci: Add routines to save/restore all counters Suzuki K Poulose <suzuki.poulose@arm.com> - 2016-02-23 12:00 +0100
  [PATCH 11/13] arm-cci: CCI-500: Work around PMU counter writes Suzuki K Poulose <suzuki.poulose@arm.com> - 2016-02-23 12:00 +0100
  Re: [PATCH 00/13] arm-cci: PMU driver updates for 4.6 Will Deacon <will.deacon@arm.com> - 2016-02-23 12:50 +0100
    Re: [PATCH 00/13] arm-cci: PMU driver updates for 4.6 "Suzuki K. Poulose" <Suzuki.Poulose@arm.com> - 2016-02-23 15:00 +0100
      Re: [PATCH 00/13] arm-cci: PMU driver updates for 4.6 Olof Johansson <olof@lixom.net> - 2016-02-24 18:00 +0100
        Re: [PATCH 00/13] arm-cci: PMU driver updates for 4.6 Will Deacon <will.deacon@arm.com> - 2016-02-24 18:20 +0100
          Re: [PATCH 00/13] arm-cci: PMU driver updates for 4.6 Olof Johansson <olof@lixom.net> - 2016-02-24 19:50 +0100
            Re: [PATCH 00/13] arm-cci: PMU driver updates for 4.6 Will Deacon <will.deacon@arm.com> - 2016-02-26 17:50 +0100

csiph-web