drm/i915: Extract CSB status read
This is a useful thing to have around as a function because the mechanism may
change in the future.
There is a net increase in LOC here, and it will continue to be the case on GEN8
and GEN9 - but future GENs may have an alternate mechanism for doing this.
Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452018609-10142-4-git-send-email-benjamin.widawsky@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 14affaa..23839ff 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -496,6 +496,19 @@
return false;
}
+static void get_context_status(struct intel_engine_cs *ring,
+ u8 read_pointer,
+ u32 *status, u32 *context_id)
+{
+ struct drm_i915_private *dev_priv = ring->dev->dev_private;
+
+ if (WARN_ON(read_pointer >= GEN8_CSB_ENTRIES))
+ return;
+
+ *status = I915_READ(RING_CONTEXT_STATUS_BUF_LO(ring, read_pointer));
+ *context_id = I915_READ(RING_CONTEXT_STATUS_BUF_HI(ring, read_pointer));
+}
+
/**
* intel_lrc_irq_handler() - handle Context Switch interrupts
* @ring: Engine Command Streamer to handle.
@@ -523,9 +536,9 @@
spin_lock(&ring->execlist_lock);
while (read_pointer < write_pointer) {
- read_pointer++;
- status = I915_READ(RING_CONTEXT_STATUS_BUF_LO(ring, read_pointer % GEN8_CSB_ENTRIES));
- status_id = I915_READ(RING_CONTEXT_STATUS_BUF_HI(ring, read_pointer % GEN8_CSB_ENTRIES));
+
+ get_context_status(ring, ++read_pointer % GEN8_CSB_ENTRIES,
+ &status, &status_id);
if (status & GEN8_CTX_STATUS_IDLE_ACTIVE)
continue;