drm/i915/irq: split ILK display irq handling

Split out display irq handling on ilk. Since the master IRQ enable is in
DEIIR, we'll need to do this in two parts. First, add
ilk_display_irq_master_disable() to disable master and south interrupts,
and second, add (repurposed) ilk_display_irq_handler() to finish display
irq handling.

It's not the prettiest thing you ever saw, but improves separation of
display irq handling. And removes HAS_PCH_NOP() and DISPLAY_VER() checks
from core irq code.

v2:
- Separate ilk_display_irq_master_enable() (Ville)
- Use _fw mmio accessors (Ville)

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://lore.kernel.org/r/e8ea7c985c3f3a80870f3333bde2e1bf30d653b0.1758637773.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

1 files changed, 49 insertions, 2 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_display_irq.c b/drivers/gpu/drm/i915/display/intel_display_irq.c
index 4d51900123ea..e1a812f6159b 100644
--- a/drivers/gpu/drm/i915/display/intel_display_irq.c
+++ b/drivers/gpu/drm/i915/display/intel_display_irq.c
@@ -872,7 +872,7 @@ static void ilk_gtt_fault_irq_handler(struct intel_display *display)
 	}
 }
 
-void ilk_display_irq_handler(struct intel_display *display, u32 de_iir)
+static void _ilk_display_irq_handler(struct intel_display *display, u32 de_iir)
 {
 	enum pipe pipe;
 	u32 hotplug_trigger = de_iir & DE_DP_A_HOTPLUG;
@@ -923,7 +923,7 @@ void ilk_display_irq_handler(struct intel_display *display, u32 de_iir)
 		ilk_display_rps_irq_handler(display);
 }
 
-void ivb_display_irq_handler(struct intel_display *display, u32 de_iir)
+static void _ivb_display_irq_handler(struct intel_display *display, u32 de_iir)
 {
 	enum pipe pipe;
 	u32 hotplug_trigger = de_iir & DE_DP_A_HOTPLUG_IVB;
@@ -972,6 +972,53 @@ void ivb_display_irq_handler(struct intel_display *display, u32 de_iir)
 	}
 }
 
+void ilk_display_irq_master_disable(struct intel_display *display, u32 *de_ier, u32 *sde_ier)
+{
+	/* disable master interrupt before clearing iir  */
+	*de_ier = intel_de_read_fw(display, DEIER);
+	intel_de_write_fw(display, DEIER, *de_ier & ~DE_MASTER_IRQ_CONTROL);
+
+	/*
+	 * Disable south interrupts. We'll only write to SDEIIR once, so further
+	 * interrupts will be stored on its back queue, and then we'll be able
+	 * to process them after we restore SDEIER (as soon as we restore it,
+	 * we'll get an interrupt if SDEIIR still has something to process due
+	 * to its back queue).
+	 */
+	if (!HAS_PCH_NOP(display)) {
+		*sde_ier = intel_de_read_fw(display, SDEIER);
+		intel_de_write_fw(display, SDEIER, 0);
+	} else {
+		*sde_ier = 0;
+	}
+}
+
+void ilk_display_irq_master_enable(struct intel_display *display, u32 de_ier, u32 sde_ier)
+{
+	intel_de_write_fw(display, DEIER, de_ier);
+
+	if (sde_ier)
+		intel_de_write_fw(display, SDEIER, sde_ier);
+}
+
+bool ilk_display_irq_handler(struct intel_display *display)
+{
+	u32 de_iir;
+	bool handled = false;
+
+	de_iir = intel_de_read_fw(display, DEIIR);
+	if (de_iir) {
+		intel_de_write_fw(display, DEIIR, de_iir);
+		if (DISPLAY_VER(display) >= 7)
+			_ivb_display_irq_handler(display, de_iir);
+		else
+			_ilk_display_irq_handler(display, de_iir);
+		handled = true;
+	}
+
+	return handled;
+}
+
 static u32 gen8_de_port_aux_mask(struct intel_display *display)
 {
 	u32 mask;