sel4: add MSI support for x86

Fixes genodelabs#5423
alex-ab · Jan 16, 2025 · 7024dbd · 7024dbd
1 parent 266dd0b
commit 7024dbd
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Showing 6 changed files with 52 additions and 27 deletions.
diff --git a/repos/base-sel4/src/core/include/irq_object.h b/repos/base-sel4/src/core/include/irq_object.h
@@ -23,6 +23,7 @@
 
 /* core includes */
 #include <types.h>
+#include <irq_args.h>
 
 namespace Core { class Irq_object; }
 
@@ -41,19 +42,22 @@ class Core::Irq_object : public Thread {
 
 		void entry() override;
 
-		long _associate(Irq_session::Trigger const &irq_trigger,
-		                Irq_session::Polarity const &irq_polarity);
+		long _associate(Irq_args const &);
 
 	public:
 
+		enum { MSI_OFFSET = 64 };
+
 		Irq_object(unsigned irq);
 
 		void sigh(Signal_context_capability cap) { _sig_cap = cap; }
 		void notify() { Signal_transmitter(_sig_cap).submit(1); }
 		void ack_irq();
 
 		Start_result start() override;
-		bool associate(Irq_session::Trigger const, Irq_session::Polarity const);
+		bool associate(Irq_args const &);
+
+		bool msi() const { return _irq >= MSI_OFFSET; }
 };
 
 #endif /* _CORE__INCLUDE__IRQ_OBJECT_H_ */
diff --git a/repos/base-sel4/src/core/irq_session_component.cc b/repos/base-sel4/src/core/irq_session_component.cc
@@ -22,12 +22,11 @@
 using namespace Core;
 
 
-bool Irq_object::associate(Irq_session::Trigger const irq_trigger,
-                           Irq_session::Polarity const irq_polarity)
+bool Irq_object::associate(Irq_args const &args)
 {
 	/* allocate notification object within core's CNode */
-	Platform &platform = platform_specific();
-	Range_allocator &phys_alloc = platform.ram_alloc();
+	auto &platform   = platform_specific();
+	auto &phys_alloc = platform.ram_alloc();
 
 	{
 		addr_t       const phys_addr = Untyped_memory::alloc_page(phys_alloc);
@@ -38,7 +37,7 @@ bool Irq_object::associate(Irq_session::Trigger const irq_trigger,
 	}
 
 	/* setup IRQ platform specific */
-	long res = _associate(irq_trigger, irq_polarity);
+	long res = _associate(args);
 	if (res != seL4_NoError)
 		return false;
 
@@ -100,22 +99,19 @@ Irq_object::Irq_object(unsigned irq)
 Irq_session_component::Irq_session_component(Range_allocator &irq_alloc,
                                              const char      *args)
 :
-	_irq_number((unsigned)Arg_string::find_arg(args, "irq_number").long_value(-1)),
+	_irq_number(Irq_args(args).irq_number() +
+	            Irq_args(args).type() != TYPE_LEGACY ? Irq_object::MSI_OFFSET : 0),
 	_irq_alloc(irq_alloc),
 	_irq_object(_irq_number)
 {
 	Irq_args const irq_args(args);
-	bool msi { irq_args.type() != Irq_session::TYPE_LEGACY };
-	if (msi)
-		throw Service_denied();
 
 	if (irq_alloc.alloc_addr(1, _irq_number).failed()) {
 		error("unavailable IRQ ", _irq_number, " requested");
 		throw Service_denied();
 	}
 
-
-	if (!_irq_object.associate(irq_args.trigger(), irq_args.polarity())) {
+	if (!_irq_object.associate(irq_args)) {
 		error("could not associate with IRQ ", irq_args.irq_number());
 		throw Service_denied();
 	}
@@ -144,6 +140,13 @@ void Irq_session_component::sigh(Signal_context_capability cap)
 
 Irq_session::Info Irq_session_component::info()
 {
-	/* no MSI support */
-	return { .type = Info::Type::INVALID, .address = 0, .value = 0 };
+	if (!_irq_object.msi())
+		return { .type = Info::Type::INVALID, .address = 0, .value = 0 };
+
+	// see include/plat/pc99/plat/machine.h
+	enum { PIC_IRQ_LINES = 16, IRQ_INT_OFFSET = 0x20 };
+
+	return { .type    = Info::Type::MSI,
+	         .address = 0xfee00000ul,
+	         .value   = IRQ_INT_OFFSET + PIC_IRQ_LINES + _irq_number };
 }
diff --git a/repos/base-sel4/src/core/platform.cc b/repos/base-sel4/src/core/platform.cc
@@ -380,6 +380,7 @@ void Core::Platform::_init_rom_modules()
 				xml.node("kernel", [&] {
 					xml.attribute("name", "sel4");
 					xml.attribute("acpi", true);
+					xml.attribute("msi" , true);
 				});
 				xml.node("hardware", [&] {
 					xml.node("features", [&] {

diff --git a/repos/base-sel4/src/core/spec/arm/irq.cc b/repos/base-sel4/src/core/spec/arm/irq.cc
@@ -11,8 +11,7 @@
 using namespace Core;
 
 
-long Irq_object::_associate(Irq_session::Trigger const &,
-                            Irq_session::Polarity const &)
+long Irq_object::_associate(Irq_args const &)
 {
 	seL4_CNode const root  = seL4_CapInitThreadCNode;
 	seL4_Word  const index = _kernel_irq_sel.value();

diff --git a/repos/base-sel4/src/core/spec/x86/irq.cc b/repos/base-sel4/src/core/spec/x86/irq.cc
@@ -12,27 +12,38 @@
 using namespace Core;
 
 
-long Irq_object::_associate(Irq_session::Trigger  const &irq_trigger,
-                            Irq_session::Polarity const &irq_polarity)
+long Irq_object::_associate(Irq_args const & args)
 {
 	enum { IRQ_EDGE = 0, IRQ_LEVEL = 1 };
 	enum { IRQ_HIGH = 0, IRQ_LOW = 1 };
 
 	seL4_Word level    = (_irq < 16) ? IRQ_EDGE : IRQ_LEVEL;
 	seL4_Word polarity = (_irq < 16) ? IRQ_HIGH : IRQ_LOW;
 
-	if (irq_trigger != Irq_session::TRIGGER_UNCHANGED)
-		level = (irq_trigger == Irq_session::TRIGGER_LEVEL) ? IRQ_LEVEL : IRQ_EDGE;
+	if (args.trigger() != Irq_session::TRIGGER_UNCHANGED)
+		level = (args.trigger() == Irq_session::TRIGGER_LEVEL) ? IRQ_LEVEL : IRQ_EDGE;
 
-	if (irq_polarity != Irq_session::POLARITY_UNCHANGED)
-		polarity = (irq_polarity == Irq_session::POLARITY_HIGH) ? IRQ_HIGH : IRQ_LOW;
+	if (args.polarity() != Irq_session::POLARITY_UNCHANGED)
+		polarity = (args.polarity() == Irq_session::POLARITY_HIGH) ? IRQ_HIGH : IRQ_LOW;
 
 	seL4_CNode const root   = seL4_CapInitThreadCNode;
 	seL4_Word  const index  = _kernel_irq_sel.value();
 	seL4_Uint8 const depth  = 32;
 	seL4_Word  const ioapic = 0;
 	seL4_Word  const pin    = _irq ? _irq : 2;
 	seL4_Word  const vector = _irq;
-	return seL4_IRQControl_GetIOAPIC(seL4_CapIRQControl, root, index, depth,
-	                                 ioapic, pin, level, polarity, vector);
+	seL4_Word  const handle = 0;
+
+	switch (args.type()) {
+	case Irq_session::TYPE_LEGACY:
+		return seL4_IRQControl_GetIOAPIC(seL4_CapIRQControl, root, index, depth,
+		                                 ioapic, pin, level, polarity, vector);
+	case Irq_session::TYPE_MSI:
+	case Irq_session::TYPE_MSIX:
+		return seL4_IRQControl_GetMSI(seL4_CapIRQControl, root, index, depth,
+		                              args.pci_bus(), args.pci_dev(),
+		                              args.pci_func(), handle, vector);
+	default:
+		return seL4_InvalidArgument;
+	}
 }
diff --git a/repos/base/src/core/include/irq_args.h b/repos/base/src/core/include/irq_args.h
@@ -33,11 +33,14 @@ class Core::Irq_args
 
 		long const _irq_number;
 
+		long const _bdf;
+
 	public:
 
 		Irq_args(const char * args)
 		:
-			_irq_number(Arg_string::find_arg(args, "irq_number").long_value(-1))
+			_irq_number(Arg_string::find_arg(args, "irq_number").long_value(-1)),
+			_bdf(Arg_string::find_arg(args, "bdf").long_value(-1))
 		{
 			long irq_trg  = Arg_string::find_arg(args, "irq_trigger").long_value(-1);
 			long irq_pol  = Arg_string::find_arg(args, "irq_polarity").long_value(-1);
@@ -99,6 +102,10 @@ class Core::Irq_args
 		Irq_session::Trigger  trigger()    const { return _irq_trigger; }
 		Irq_session::Polarity polarity()   const { return _irq_polarity; }
 		Irq_session::Type     type()       const { return _irq_type; }
+
+		unsigned pci_bus()  const { return 0xffu & (_bdf >> 8); }
+		unsigned pci_dev()  const { return 0x1fu & (_bdf >> 3); }
+		unsigned pci_func() const { return 0x07u & _bdf; }
 };
 
 #endif /* _CORE__INCLUDE__IRQ_ARGS_H_ */