Commit 956deab5 authored by Krzysztof Kozlowski's avatar Krzysztof Kozlowski Committed by Bjorn Andersson
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soc: qcom: icc-bwmon: clear all registers on init 



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: default avatarKrzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Tested-by: default avatarSteev Klimaszewski <steev@kali.org>
Signed-off-by: default avatarBjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220728113748.170548-6-krzysztof.kozlowski@linaro.org
parent 1dd5246e

drivers/soc/qcom/icc-bwmon.c

+9 −4
Original line number Diff line number Diff line
@@ -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);