uncore->lock only protects the forcewake domain itself,
not the register accesses.
uncore's _fw alternatives are for cases where the domains
are not needed because we are sure that they are already
awake.
So the move towards the uncore's _fw alternatives seems
right, however using the uncore-lock to protect the dsparb
registers seems an abuse of the uncore-lock.
Let's restore the previous individual lock and try to get
rid of the direct uncore accesses from the display code.
Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Cc: Jani Nikula <jani.nikula@xxxxxxxxx>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
---
drivers/gpu/drm/i915/display/i9xx_wm.c | 13 ++-----------
drivers/gpu/drm/i915/display/intel_display_core.h | 3 +++
drivers/gpu/drm/i915/i915_driver.c | 1 +
3 files changed, 6 insertions(+), 11 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/i9xx_wm.c b/drivers/gpu/drm/i915/display/i9xx_wm.c
index caef72d38798..8fe0b5c63d3a 100644
--- a/drivers/gpu/drm/i915/display/i9xx_wm.c
+++ b/drivers/gpu/drm/i915/display/i9xx_wm.c
@@ -1771,16 +1771,7 @@ static void vlv_atomic_update_fifo(struct intel_atomic_state *state,
trace_vlv_fifo_size(crtc, sprite0_start, sprite1_start, fifo_size);
- /*
- * uncore.lock serves a double purpose here. It allows us to
- * use the less expensive I915_{READ,WRITE}_FW() functions, and
- * it protects the DSPARB registers from getting clobbered by
- * parallel updates from multiple pipes.
- *
- * intel_pipe_update_start() has already disabled interrupts
- * for us, so a plain spin_lock() is sufficient here.
- */
- spin_lock(&uncore->lock);
+ spin_lock(&dev_priv->display.wm.dsparb_lock);
switch (crtc->pipe) {
case PIPE_A:
@@ -1840,7 +1831,7 @@ static void vlv_atomic_update_fifo(struct intel_atomic_state *state,
intel_uncore_posting_read_fw(uncore, DSPARB);
- spin_unlock(&uncore->lock);
+ spin_unlock(&dev_priv->display.wm.dsparb_lock);
}
#undef VLV_FIFO
diff --git a/drivers/gpu/drm/i915/display/intel_display_core.h b/drivers/gpu/drm/i915/display/intel_display_core.h
index fdab7bb93a7d..68c6bfb91dbe 100644
--- a/drivers/gpu/drm/i915/display/intel_display_core.h
+++ b/drivers/gpu/drm/i915/display/intel_display_core.h
@@ -253,6 +253,9 @@ struct intel_wm {
*/
struct mutex wm_mutex;
+ /* protects DSPARB registers on pre-g4x/vlv/chv */
+ spinlock_t dsparb_lock;
+
bool ipc_enabled;
};
diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
index a53fd339e2cc..c78e36444a12 100644
--- a/drivers/gpu/drm/i915/i915_driver.c
+++ b/drivers/gpu/drm/i915/i915_driver.c
@@ -223,6 +223,7 @@ static int i915_driver_early_probe(struct drm_i915_private *dev_priv)
mutex_init(&dev_priv->display.pps.mutex);
mutex_init(&dev_priv->display.hdcp.comp_mutex);
spin_lock_init(&dev_priv->display.dkl.phy_lock);
+ spin_lock_init(&dev_priv->display.wm.dsparb_lock);
i915_memcpy_init_early(dev_priv);
intel_runtime_pm_init_early(&dev_priv->runtime_pm);
--
2.39.2
