drm/nva3/backlight: add suppport for newer style backlight regs

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nouveau_backlight.c

@@ -103,7 +103,8 @@ nv50_get_intensity(struct backlight_device *bd)
 	u32 div = 1025;
 	u32 val;
 
-	val = nv_rd32(dev, NV50_PDISPLAY_SOR_BACKLIGHT + (or * 0x800));
+	val  = nv_rd32(dev, NV50_PDISP_SOR_PWM_CTL(or));
+	val &= NV50_PDISP_SOR_PWM_CTL_VAL;
 	return ((val * 100) + (div / 2)) / div;
 }
 
@@ -116,8 +117,8 @@ nv50_set_intensity(struct backlight_device *bd)
 	u32 div = 1025;
 	u32 val = (bd->props.brightness * div) / 100;
 
-	nv_wr32(dev, NV50_PDISPLAY_SOR_BACKLIGHT + (or * 0x800),
+	nv_wr32(dev, NV50_PDISP_SOR_PWM_CTL(or),
-		val | NV50_PDISPLAY_SOR_BACKLIGHT_ENABLE);
+		     NV50_PDISP_SOR_PWM_CTL_NEW | val);
 	return 0;
 }
 
@@ -127,6 +128,49 @@ static const struct backlight_ops nv50_bl_ops = {
 	.update_status = nv50_set_intensity,
 };
 
+static int
+nva3_get_intensity(struct backlight_device *bd)
+{
+	struct nouveau_encoder *nv_encoder = bl_get_data(bd);
+	struct drm_device *dev = nv_encoder->base.base.dev;
+	int or = nv_encoder->or;
+	u32 div, val;
+
+	div  = nv_rd32(dev, NV50_PDISP_SOR_PWM_DIV(or));
+	val  = nv_rd32(dev, NV50_PDISP_SOR_PWM_CTL(or));
+	val &= NVA3_PDISP_SOR_PWM_CTL_VAL;
+	if (div && div >= val)
+		return ((val * 100) + (div / 2)) / div;
+
+	return 100;
+}
+
+static int
+nva3_set_intensity(struct backlight_device *bd)
+{
+	struct nouveau_encoder *nv_encoder = bl_get_data(bd);
+	struct drm_device *dev = nv_encoder->base.base.dev;
+	int or = nv_encoder->or;
+	u32 div, val;
+
+	div = nv_rd32(dev, NV50_PDISP_SOR_PWM_DIV(or));
+	val = (bd->props.brightness * div) / 100;
+	if (div) {
+		nv_wr32(dev, NV50_PDISP_SOR_PWM_CTL(or), val |
+			     NV50_PDISP_SOR_PWM_CTL_NEW |
+			     NVA3_PDISP_SOR_PWM_CTL_UNK);
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static const struct backlight_ops nva3_bl_ops = {
+	.options = BL_CORE_SUSPENDRESUME,
+	.get_brightness = nva3_get_intensity,
+	.update_status = nva3_set_intensity,
+};
+
 static int
 nv50_backlight_init(struct drm_connector *connector)
 {
@@ -135,7 +179,7 @@ nv50_backlight_init(struct drm_connector *connector)
 	struct nouveau_encoder *nv_encoder;
 	struct backlight_properties props;
 	struct backlight_device *bd;
-	int or;
+	const struct backlight_ops *ops;
 
 	nv_encoder = find_encoder(connector, OUTPUT_LVDS);
 	if (!nv_encoder) {
@@ -144,21 +188,26 @@ nv50_backlight_init(struct drm_connector *connector)
 			return -ENODEV;
 	}
 
-	or = nv_encoder->or;
+	if (!nv_rd32(dev, NV50_PDISP_SOR_PWM_CTL(nv_encoder->or)))
-
-	if (!nv_rd32(dev, NV50_PDISPLAY_SOR_BACKLIGHT + (or * 0x800)))
 		return 0;
 
+	if (dev_priv->chipset <= 0xa0 ||
+	    dev_priv->chipset == 0xaa ||
+	    dev_priv->chipset == 0xac)
+		ops = &nv50_bl_ops;
+	else
+		ops = &nva3_bl_ops;
+
 	memset(&props, 0, sizeof(struct backlight_properties));
 	props.type = BACKLIGHT_RAW;
 	props.max_brightness = 100;
 	bd = backlight_device_register("nv_backlight", &connector->kdev,
-				       nv_encoder, &nv50_bl_ops, &props);
+				       nv_encoder, ops, &props);
 	if (IS_ERR(bd))
 		return PTR_ERR(bd);
 
 	dev_priv->backlight = bd;
-	bd->props.brightness = nv50_get_intensity(bd);
+	bd->props.brightness = bd->ops->get_brightness(bd);
 	backlight_update_status(bd);
 	return 0;
 }

drivers/gpu/drm/nouveau/nouveau_reg.h

@@ -826,9 +826,12 @@
 #define NV50_PDISPLAY_SOR_DPMS_STATE_ACTIVE                          0x00030000
 #define NV50_PDISPLAY_SOR_DPMS_STATE_BLANKED                         0x00080000
 #define NV50_PDISPLAY_SOR_DPMS_STATE_WAIT                            0x10000000
-#define NV50_PDISPLAY_SOR_BACKLIGHT                                  0x0061c084
+#define NV50_PDISP_SOR_PWM_DIV(i)                     (0x0061c080 + (i) * 0x800)
-#define NV50_PDISPLAY_SOR_BACKLIGHT_ENABLE                           0x80000000
+#define NV50_PDISP_SOR_PWM_CTL(i)                     (0x0061c084 + (i) * 0x800)
-#define NV50_PDISPLAY_SOR_BACKLIGHT_LEVEL                            0x00000fff
+#define NV50_PDISP_SOR_PWM_CTL_NEW                                   0x80000000
+#define NVA3_PDISP_SOR_PWM_CTL_UNK                                   0x40000000
+#define NV50_PDISP_SOR_PWM_CTL_VAL                                   0x000007ff
+#define NVA3_PDISP_SOR_PWM_CTL_VAL                                   0x00ffffff
 #define NV50_SOR_DP_CTRL(i, l)           (0x0061c10c + (i) * 0x800 + (l) * 0x80)
 #define NV50_SOR_DP_CTRL_ENABLED                                     0x00000001
 #define NV50_SOR_DP_CTRL_ENHANCED_FRAME_ENABLED                      0x00004000