drm/radeon: add support for interrupts on CIK (v5)

Todo:
- handle interrupts for compute queues

v2: add documentation
v3: update to latest reset code
v4: update to latest illegal CP handling
v5: fix missing break in interrupt handler switch statement
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/radeon.h

@@ -600,10 +600,21 @@ struct evergreen_irq_stat_regs {
 	u32 afmt_status6;
 };
 
+struct cik_irq_stat_regs {
+	u32 disp_int;
+	u32 disp_int_cont;
+	u32 disp_int_cont2;
+	u32 disp_int_cont3;
+	u32 disp_int_cont4;
+	u32 disp_int_cont5;
+	u32 disp_int_cont6;
+};
+
 union radeon_irq_stat_regs {
 	struct r500_irq_stat_regs r500;
 	struct r600_irq_stat_regs r600;
 	struct evergreen_irq_stat_regs evergreen;
+	struct cik_irq_stat_regs cik;
 };
 
 #define RADEON_MAX_HPD_PINS 6