hw/rpi: USB SOF interrupt filtering

repos/base-hw/src/core/include/spec/rpi/pic.h

@@ -26,8 +26,111 @@ namespace Genode
 	 * Programmable interrupt controller for core
 	 */
 	class Pic;
+
+	class Usb_dwc_otg;
 }
 
+
+class Genode::Usb_dwc_otg : Mmio
+{
+	private:
+
+		struct Core_irq_status : Register<0x14, 32>
+		{
+			struct Sof : Bitfield<3, 1> { };
+		};
+
+		struct Guid : Register<0x3c, 32>
+		{
+			struct Num : Bitfield<0, 14> { };
+
+			/*
+			 * The USB driver set 'Num' to a defined value
+			 */
+			struct Num_valid : Bitfield<31, 1> { };
+
+			/*
+			 * Filter is not used, overridden by the USB driver
+			 */
+			struct Kick : Bitfield<30, 1> { };
+		};
+
+		struct Host_frame_number : Register<0x408, 32>
+		{
+			struct Num : Bitfield<0, 14> { };
+		};
+
+		bool _is_sof() const
+		{
+			return read<Core_irq_status::Sof>();
+		}
+
+		static bool _need_trigger_sof(uint32_t host_frame,
+		                              uint32_t scheduled_frame)
+		{
+			uint32_t const max_frame = 0x3fff;
+
+			if (host_frame < scheduled_frame) {
+				if (scheduled_frame - host_frame < max_frame / 2)
+					return false;  /* scheduled frame not reached yet */
+				else
+					return true;   /* scheduled frame passed, host frame wrapped */
+			} else {
+				if (host_frame - scheduled_frame < max_frame / 2)
+					return true;   /* scheduled frame passed */
+				else
+					return false;  /* scheduled frame wrapped, not reached */
+			}
+		}
+
+	public:
+
+		Usb_dwc_otg() : Mmio(Board::USB_DWC_OTG_BASE)
+		{
+			write<Guid::Num>(0);
+			write<Guid::Num_valid>(false);
+			write<Guid::Kick>(false);
+		}
+
+		bool handle_sof()
+		{
+			if (!_is_sof())
+				return false;
+
+			static int cnt, stat_cnt, filter_cnt, trigger_cnt, kick_cnt;
+
+			stat_cnt++;
+			if (stat_cnt == 8000) {
+				PLOG("kicked: %d filtered: %d  triggered: %d", kick_cnt, filter_cnt, trigger_cnt);
+				stat_cnt = 0;
+			}
+
+			cnt++;
+			if (cnt == 8*20) {
+				cnt = 0;
+				return false;
+			}
+
+			if (read<Guid::Kick>())
+				kick_cnt++;
+
+			if (!read<Guid::Num_valid>() || read<Guid::Kick>())
+				return false;
+
+			if (_need_trigger_sof(read<Host_frame_number::Num>(), read<Guid::Num>())) {
+				trigger_cnt++;
+				return false;
+			}
+
+			filter_cnt++;
+
+			write<Core_irq_status::Sof>(1);
+
+			return true;
+		}
+};
+
+
 class Genode::Pic : Mmio
 {
 	public:
@@ -51,6 +154,8 @@ class Genode::Pic : Mmio
 		struct Irq_disable_gpu_2  : Register<0x20, 32> { };
 		struct Irq_disable_basic  : Register<0x24, 32> { };
 
+		Usb_dwc_otg _usb;
+
 		/**
 		 * Return true if specified interrupt is pending
 		 */
@@ -89,6 +194,12 @@ class Genode::Pic : Mmio
 					continue;
 
 				irq = Board_base::GPU_IRQ_BASE + i;
+
+				/* handle SOF interrupts locally, filter from the user land */
+				if (irq == Board_base::DWC_IRQ)
+					if (_usb.handle_sof())
+						return false;
+
 				return true;
 			}
 

repos/base-hw/src/core/spec/rpi/platform_support.cc

@@ -51,6 +51,9 @@ Native_region * Platform::_core_only_mmio_regions(unsigned const i)
 
 		/* IRQ controller */
 		{ Board::IRQ_CONTROLLER_BASE, Board::IRQ_CONTROLLER_SIZE },
+
+		/* DWC OTG USB controller (used for in-kernel SOF IRQ handling) */
+		{ Board::USB_DWC_OTG_BASE, Board::USB_DWC_OTG_SIZE },
 	};
 	return i < sizeof(_regions)/sizeof(_regions[0]) ? &_regions[i] : 0;
 }

repos/base/include/platform/rpi/drivers/board_base.h

@@ -48,6 +48,9 @@ namespace Genode
 			IRQ_CONTROLLER_BASE = 0x2000b200,
 			IRQ_CONTROLLER_SIZE = 0x100,
 
+			USB_DWC_OTG_BASE = 0x20980000,
+			USB_DWC_OTG_SIZE = 0x20000,
+
 			/* timer */
 			TIMER_IRQ = 0,