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soc: qcom: icc-bwmon: clear all registers on init

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The hardware programming guide recommends to clear all registers on
first initialization, through separate field in BWMON_CLEAR register.

This makes sense in general but especially if driver is rebound to avoid
spurious/early interrupts.

Cc: Rajendra Nayak <quic_rjendra@quicinc.com>
Cc: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Tested-by: Steev Klimaszewski <steev@kali.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220728113748.170548-6-krzysztof.kozlowski@linaro.org
This commit is contained in:
Krzysztof Kozlowski 2022-07-28 13:37:42 +02:00 committed by Bjorn Andersson
parent 1dd5246ea6
commit 956deab551
1 changed files with 9 additions and 4 deletions
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13
drivers/soc/qcom/icc-bwmon.c
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@ -50,6 +50,7 @@
#define BWMON_CLEAR 0x2a4
#define BWMON_CLEAR_CLEAR BIT(0)
#define BWMON_CLEAR_CLEAR_ALL BIT(1)
#define BWMON_SAMPLE_WINDOW 0x2a8
#define BWMON_THRESHOLD_HIGH 0x2ac
@ -127,8 +128,12 @@ struct icc_bwmon {
unsigned int current_kbps;
};
static void bwmon_clear_counters(struct icc_bwmon *bwmon)
static void bwmon_clear_counters(struct icc_bwmon *bwmon, bool clear_all)
{
unsigned int val = BWMON_CLEAR_CLEAR;
if (clear_all)
val |= BWMON_CLEAR_CLEAR_ALL;
/*
* Clear counters. The order and barriers are
* important. Quoting downstream Qualcomm msm-4.9 tree:
@ -137,7 +142,7 @@ static void bwmon_clear_counters(struct icc_bwmon *bwmon)
* region. So, we need to make sure the counter clear is completed
* before we try to clear the IRQ or do any other counter operations.
*/
writel(BWMON_CLEAR_CLEAR, bwmon->base + BWMON_CLEAR);
writel(val, bwmon->base + BWMON_CLEAR);
}
static void bwmon_clear_irq(struct icc_bwmon *bwmon)
@ -208,7 +213,7 @@ static void bwmon_start(struct icc_bwmon *bwmon)
unsigned int thres_count;
int window;
bwmon_clear_counters(bwmon);
bwmon_clear_counters(bwmon, true);
window = mult_frac(bwmon->data->sample_ms, HW_TIMER_HZ, MSEC_PER_SEC);
/* Maximum sampling window: 0xfffff */
@ -304,7 +309,7 @@ static irqreturn_t bwmon_intr_thread(int irq, void *dev_id)
bwmon_set_threshold(bwmon, BWMON_THRESHOLD_HIGH, up_kbps);
bwmon_set_threshold(bwmon, BWMON_THRESHOLD_MED, down_kbps);
/* Write barriers in bwmon_clear_counters() */
bwmon_clear_counters(bwmon);
bwmon_clear_counters(bwmon, false);
bwmon_clear_irq(bwmon);
bwmon_enable(bwmon, irq_enable);