[PATCH v6 18/26] PM / devfreq: rockchip-dfi: account for multiple DDRMON_CTRL registers

[Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>]

The currently supported RK3399 has a set of registers per channel, but
it has only a single DDRMON_CTRL register. With upcoming RK3588 this
will be different, the RK3588 has a DDRMON_CTRL register per channel.

Instead of expecting a single DDRMON_CTRL register, loop over the
channels and write the channel specific DDRMON_CTRL register. Break
out early out of the loop when there is only a single DDRMON_CTRL
register like on the RK3399.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Reviewed-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230524083153.2046084-19-s.hauer@xxxxxxxxxxxxxx
Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
---
 drivers/devfreq/event/rockchip-dfi.c | 72 ++++++++++++++++++----------
 1 file changed, 48 insertions(+), 24 deletions(-)

diff --git a/drivers/devfreq/event/rockchip-dfi.c b/drivers/devfreq/event/rockchip-dfi.c
index 85ec93fd41858..2362d3953ba40 100644
--- a/drivers/devfreq/event/rockchip-dfi.c
+++ b/drivers/devfreq/event/rockchip-dfi.c
@@ -113,12 +113,13 @@ struct rockchip_dfi {
 	int burst_len;
 	int buswidth[DMC_MAX_CHANNELS];
 	int ddrmon_stride;
+	bool ddrmon_ctrl_single;
 };
 
 static int rockchip_dfi_enable(struct rockchip_dfi *dfi)
 {
 	void __iomem *dfi_regs = dfi->regs;
-	int ret = 0;
+	int i, ret = 0;
 
 	mutex_lock(&dfi->mutex);
 
@@ -132,29 +133,41 @@ static int rockchip_dfi_enable(struct rockchip_dfi *dfi)
 		goto out;
 	}
 
-	/* clear DDRMON_CTRL setting */
-	writel_relaxed(HIWORD_UPDATE(0, DDRMON_CTRL_TIMER_CNT_EN | DDRMON_CTRL_SOFTWARE_EN |
-		       DDRMON_CTRL_HARDWARE_EN), dfi_regs + DDRMON_CTRL);
+	for (i = 0; i < DMC_MAX_CHANNELS; i++) {
+		u32 ctrl = 0;
 
-	/* set ddr type to dfi */
-	switch (dfi->ddr_type) {
-	case ROCKCHIP_DDRTYPE_LPDDR2:
-	case ROCKCHIP_DDRTYPE_LPDDR3:
-		writel_relaxed(HIWORD_UPDATE(DDRMON_CTRL_LPDDR23, DDRMON_CTRL_DDR_TYPE_MASK),
-			       dfi_regs + DDRMON_CTRL);
-		break;
-	case ROCKCHIP_DDRTYPE_LPDDR4:
-	case ROCKCHIP_DDRTYPE_LPDDR4X:
-		writel_relaxed(HIWORD_UPDATE(DDRMON_CTRL_LPDDR4, DDRMON_CTRL_DDR_TYPE_MASK),
-			       dfi_regs + DDRMON_CTRL);
-		break;
-	default:
-		break;
-	}
+		if (!(dfi->channel_mask & BIT(i)))
+			continue;
 
-	/* enable count, use software mode */
-	writel_relaxed(HIWORD_UPDATE(DDRMON_CTRL_SOFTWARE_EN, DDRMON_CTRL_SOFTWARE_EN),
-		       dfi_regs + DDRMON_CTRL);
+		/* clear DDRMON_CTRL setting */
+		writel_relaxed(HIWORD_UPDATE(0, DDRMON_CTRL_TIMER_CNT_EN |
+			       DDRMON_CTRL_SOFTWARE_EN | DDRMON_CTRL_HARDWARE_EN),
+			       dfi_regs + i * dfi->ddrmon_stride + DDRMON_CTRL);
+
+		/* set ddr type to dfi */
+		switch (dfi->ddr_type) {
+		case ROCKCHIP_DDRTYPE_LPDDR2:
+		case ROCKCHIP_DDRTYPE_LPDDR3:
+			ctrl = DDRMON_CTRL_LPDDR23;
+			break;
+		case ROCKCHIP_DDRTYPE_LPDDR4:
+		case ROCKCHIP_DDRTYPE_LPDDR4X:
+			ctrl = DDRMON_CTRL_LPDDR4;
+			break;
+		default:
+			break;
+		}
+
+		writel_relaxed(HIWORD_UPDATE(ctrl, DDRMON_CTRL_DDR_TYPE_MASK),
+			       dfi_regs + i * dfi->ddrmon_stride + DDRMON_CTRL);
+
+		/* enable count, use software mode */
+		writel_relaxed(HIWORD_UPDATE(DDRMON_CTRL_SOFTWARE_EN, DDRMON_CTRL_SOFTWARE_EN),
+			       dfi_regs + i * dfi->ddrmon_stride + DDRMON_CTRL);
+
+		if (dfi->ddrmon_ctrl_single)
+			break;
+	}
 out:
 	mutex_unlock(&dfi->mutex);
 
@@ -164,6 +177,7 @@ static int rockchip_dfi_enable(struct rockchip_dfi *dfi)
 static void rockchip_dfi_disable(struct rockchip_dfi *dfi)
 {
 	void __iomem *dfi_regs = dfi->regs;
+	int i;
 
 	mutex_lock(&dfi->mutex);
 
@@ -174,8 +188,17 @@ static void rockchip_dfi_disable(struct rockchip_dfi *dfi)
 	if (dfi->usecount > 0)
 		goto out;
 
-	writel_relaxed(HIWORD_UPDATE(0, DDRMON_CTRL_SOFTWARE_EN),
-		       dfi_regs + DDRMON_CTRL);
+	for (i = 0; i < DMC_MAX_CHANNELS; i++) {
+		if (!(dfi->channel_mask & BIT(i)))
+			continue;
+
+		writel_relaxed(HIWORD_UPDATE(0, DDRMON_CTRL_SOFTWARE_EN),
+			      dfi_regs + i * dfi->ddrmon_stride + DDRMON_CTRL);
+
+		if (dfi->ddrmon_ctrl_single)
+			break;
+	}
+
 	clk_disable_unprepare(dfi->clk);
 out:
 	mutex_unlock(&dfi->mutex);
@@ -666,6 +689,7 @@ static int rk3399_dfi_init(struct rockchip_dfi *dfi)
 	dfi->buswidth[1] = FIELD_GET(RK3399_PMUGRF_OS_REG2_BW_CH1, val) == 0 ? 4 : 2;
 
 	dfi->ddrmon_stride = 0x14;
+	dfi->ddrmon_ctrl_single = true;
 
 	return 0;
 };
-- 
2.39.2