1 files changed, 30 insertions, 22 deletions

diff --git a/drivers/devfreq/event/rockchip-dfi.c b/drivers/devfreq/event/rockchip-dfi.c
index 680f629da64f..126bb744645b 100644
--- a/drivers/devfreq/event/rockchip-dfi.c
+++ b/drivers/devfreq/event/rockchip-dfi.c
@@ -38,11 +38,15 @@
 #define DDRMON_CH1_COUNT_NUM		0x3c
 #define DDRMON_CH1_DFI_ACCESS_NUM	0x40
 
-struct dmc_usage {
+struct dmc_count_channel {
 	u32 access;
 	u32 total;
 };
 
+struct dmc_count {
+	struct dmc_count_channel c[RK3399_DMC_NUM_CH];
+};
+
 /*
  * The dfi controller can monitor DDR load. It has an upper and lower threshold
  * for the operating points. Whenever the usage leaves these bounds an event is
@@ -51,7 +55,7 @@ struct dmc_usage {
 struct rockchip_dfi {
 	struct devfreq_event_dev *edev;
 	struct devfreq_event_desc desc;
-	struct dmc_usage ch_usage[RK3399_DMC_NUM_CH];
+	struct dmc_count last_event_count;
 	struct device *dev;
 	void __iomem *regs;
 	struct regmap *regmap_pmu;
@@ -85,30 +89,18 @@ static void rockchip_dfi_stop_hardware_counter(struct devfreq_event_dev *edev)
 	writel_relaxed(SOFTWARE_DIS, dfi_regs + DDRMON_CTRL);
 }
 
-static int rockchip_dfi_get_busier_ch(struct devfreq_event_dev *edev)
+static void rockchip_dfi_read_counters(struct devfreq_event_dev *edev, struct dmc_count *count)
 {
 	struct rockchip_dfi *dfi = devfreq_event_get_drvdata(edev);
-	u32 tmp, max = 0;
-	u32 i, busier_ch = 0;
+	u32 i;
 	void __iomem *dfi_regs = dfi->regs;
 
-	rockchip_dfi_stop_hardware_counter(edev);
-
-	/* Find out which channel is busier */
 	for (i = 0; i < RK3399_DMC_NUM_CH; i++) {
-		dfi->ch_usage[i].access = readl_relaxed(dfi_regs +
+		count->c[i].access = readl_relaxed(dfi_regs +
 				DDRMON_CH0_DFI_ACCESS_NUM + i * 20);
-		dfi->ch_usage[i].total = readl_relaxed(dfi_regs +
+		count->c[i].total = readl_relaxed(dfi_regs +
 				DDRMON_CH0_COUNT_NUM + i * 20);
-		tmp = dfi->ch_usage[i].access;
-		if (tmp > max) {
-			busier_ch = i;
-			max = tmp;
-		}
 	}
-	rockchip_dfi_start_hardware_counter(edev);
-
-	return busier_ch;
 }
 
 static int rockchip_dfi_disable(struct devfreq_event_dev *edev)
@@ -145,12 +137,28 @@ static int rockchip_dfi_get_event(struct devfreq_event_dev *edev,
 				  struct devfreq_event_data *edata)
 {
 	struct rockchip_dfi *dfi = devfreq_event_get_drvdata(edev);
-	int busier_ch;
+	struct dmc_count count;
+	struct dmc_count *last = &dfi->last_event_count;
+	u32 access = 0, total = 0;
+	int i;
+
+	rockchip_dfi_read_counters(edev, &count);
+
+	/* We can only report one channel, so find the busiest one */
+	for (i = 0; i < RK3399_DMC_NUM_CH; i++) {
+		u32 a = count.c[i].access - last->c[i].access;
+		u32 t = count.c[i].total - last->c[i].total;
+
+		if (a > access) {
+			access = a;
+			total = t;
+		}
+	}
 
-	busier_ch = rockchip_dfi_get_busier_ch(edev);
+	edata->load_count = access * 4;
+	edata->total_count = total;
 
-	edata->load_count = dfi->ch_usage[busier_ch].access * 4;
-	edata->total_count = dfi->ch_usage[busier_ch].total;
+	dfi->last_event_count = count;
 
 	return 0;
 }