drm/i915: add multi-threaded forcewake support
On IVB C0+ with newer BIOSes, the forcewake handshake has changed. There's
now a bitfield for different driver components to keep the GT powered
on. On Linux, we centralize forcewake handling in one place, so we
still just need a single bit, but we need to use the new registers if MT
forcewake is enabled.
This needs testing on affected machines. Please reply with your
tested-by if you had problems after a BIOS upgrade and this patch fixes
them.
v2: force MT mode. shift by 16
v3: set MT force wake bits then check ECOBUS
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=42923
Tested-by: Manoj Iyer <manoj.iyer@canonical.com>
Tested-by: Robert Hooker <robert.hooker@canonical.com>
Tested-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 15bfa91..28836fe 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -328,7 +328,7 @@
}
}
-static void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
+void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
{
int count;
@@ -344,6 +344,22 @@
udelay(10);
}
+void __gen6_gt_force_wake_mt_get(struct drm_i915_private *dev_priv)
+{
+ int count;
+
+ count = 0;
+ while (count++ < 50 && (I915_READ_NOTRACE(FORCEWAKE_MT_ACK) & 1))
+ udelay(10);
+
+ I915_WRITE_NOTRACE(FORCEWAKE_MT, (1<<16) | 1);
+ POSTING_READ(FORCEWAKE_MT);
+
+ count = 0;
+ while (count++ < 50 && (I915_READ_NOTRACE(FORCEWAKE_MT_ACK) & 1) == 0)
+ udelay(10);
+}
+
/*
* Generally this is called implicitly by the register read function. However,
* if some sequence requires the GT to not power down then this function should
@@ -356,15 +372,21 @@
/* Forcewake is atomic in case we get in here without the lock */
if (atomic_add_return(1, &dev_priv->forcewake_count) == 1)
- __gen6_gt_force_wake_get(dev_priv);
+ dev_priv->display.force_wake_get(dev_priv);
}
-static void __gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
+void __gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
{
I915_WRITE_NOTRACE(FORCEWAKE, 0);
POSTING_READ(FORCEWAKE);
}
+void __gen6_gt_force_wake_mt_put(struct drm_i915_private *dev_priv)
+{
+ I915_WRITE_NOTRACE(FORCEWAKE_MT, (1<<16) | 0);
+ POSTING_READ(FORCEWAKE_MT);
+}
+
/*
* see gen6_gt_force_wake_get()
*/
@@ -373,7 +395,7 @@
WARN_ON(!mutex_is_locked(&dev_priv->dev->struct_mutex));
if (atomic_dec_and_test(&dev_priv->forcewake_count))
- __gen6_gt_force_wake_put(dev_priv);
+ dev_priv->display.force_wake_put(dev_priv);
}
void __gen6_gt_wait_for_fifo(struct drm_i915_private *dev_priv)
@@ -903,8 +925,9 @@
/* We give fast paths for the really cool registers */
#define NEEDS_FORCE_WAKE(dev_priv, reg) \
(((dev_priv)->info->gen >= 6) && \
- ((reg) < 0x40000) && \
- ((reg) != FORCEWAKE))
+ ((reg) < 0x40000) && \
+ ((reg) != FORCEWAKE) && \
+ ((reg) != ECOBUS))
#define __i915_read(x, y) \
u##x i915_read##x(struct drm_i915_private *dev_priv, u32 reg) { \
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 4a9c1b9..8ba88cf 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -107,6 +107,7 @@
struct opregion_acpi;
struct opregion_swsci;
struct opregion_asle;
+struct drm_i915_private;
struct intel_opregion {
struct opregion_header *header;
@@ -221,6 +222,8 @@
struct drm_i915_gem_object *obj);
int (*update_plane)(struct drm_crtc *crtc, struct drm_framebuffer *fb,
int x, int y);
+ void (*force_wake_get)(struct drm_i915_private *dev_priv);
+ void (*force_wake_put)(struct drm_i915_private *dev_priv);
/* clock updates for mode set */
/* cursor updates */
/* render clock increase/decrease */
@@ -1308,6 +1311,11 @@
extern void intel_detect_pch(struct drm_device *dev);
extern int intel_trans_dp_port_sel(struct drm_crtc *crtc);
+extern void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv);
+extern void __gen6_gt_force_wake_mt_get(struct drm_i915_private *dev_priv);
+extern void __gen6_gt_force_wake_put(struct drm_i915_private *dev_priv);
+extern void __gen6_gt_force_wake_mt_put(struct drm_i915_private *dev_priv);
+
/* overlay */
#ifdef CONFIG_DEBUG_FS
extern struct intel_overlay_error_state *intel_overlay_capture_error_state(struct drm_device *dev);
@@ -1352,8 +1360,9 @@
/* We give fast paths for the really cool registers */
#define NEEDS_FORCE_WAKE(dev_priv, reg) \
(((dev_priv)->info->gen >= 6) && \
- ((reg) < 0x40000) && \
- ((reg) != FORCEWAKE))
+ ((reg) < 0x40000) && \
+ ((reg) != FORCEWAKE) && \
+ ((reg) != ECOBUS))
#define __i915_read(x, y) \
u##x i915_read##x(struct drm_i915_private *dev_priv, u32 reg);
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index b080cc8..8990057 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3449,6 +3449,10 @@
#define FORCEWAKE 0xA18C
#define FORCEWAKE_ACK 0x130090
+#define FORCEWAKE_MT 0xa188 /* multi-threaded */
+#define FORCEWAKE_MT_ACK 0x130040
+#define ECOBUS 0xa180
+#define FORCEWAKE_MT_ENABLE (1<<5)
#define GT_FIFO_FREE_ENTRIES 0x120008
#define GT_FIFO_NUM_RESERVED_ENTRIES 20
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index e77a863..633c693 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8491,6 +8491,28 @@
/* For FIFO watermark updates */
if (HAS_PCH_SPLIT(dev)) {
+ dev_priv->display.force_wake_get = __gen6_gt_force_wake_get;
+ dev_priv->display.force_wake_put = __gen6_gt_force_wake_put;
+
+ /* IVB configs may use multi-threaded forcewake */
+ if (IS_IVYBRIDGE(dev)) {
+ u32 ecobus;
+
+ mutex_lock(&dev->struct_mutex);
+ __gen6_gt_force_wake_mt_get(dev_priv);
+ ecobus = I915_READ(ECOBUS);
+ __gen6_gt_force_wake_mt_put(dev_priv);
+ mutex_unlock(&dev->struct_mutex);
+
+ if (ecobus & FORCEWAKE_MT_ENABLE) {
+ DRM_DEBUG_KMS("Using MT version of forcewake\n");
+ dev_priv->display.force_wake_get =
+ __gen6_gt_force_wake_mt_get;
+ dev_priv->display.force_wake_put =
+ __gen6_gt_force_wake_mt_put;
+ }
+ }
+
if (HAS_PCH_IBX(dev))
dev_priv->display.init_pch_clock_gating = ibx_init_clock_gating;
else if (HAS_PCH_CPT(dev))