hw: implement MSI support for x86

Fix genodelabs/genode#4633

repos/base-hw/src/core/irq_session_component.cc

@@ -58,6 +58,7 @@ Irq_session_component::~Irq_session_component()
 	using namespace Kernel;
 
 	_irq_alloc.free((void *)(addr_t)_irq_number);
+	if (_is_msi) Platform::free_msi_vector(_address, _value);
 }
 
 
@@ -72,10 +73,10 @@ Irq_session_component::Irq_session_component(Range_allocator &irq_alloc,
 		Arg_string::find_arg(args, "device_config_phys").long_value(0);
 
 	if (mmconf) {
-		_is_msi =
-			Platform::get_msi_params(mmconf, _address, _value, _irq_number);
+		_is_msi = Platform::alloc_msi_vector(_address, _value);
 		if (!_is_msi)
 			throw Service_denied();
+		_irq_number = (unsigned) _value;
 	}
 
 	/* allocate interrupt */

repos/base-hw/src/core/platform.cc

@@ -161,6 +161,7 @@ void Platform::_init_platform_info()
 		xml.node("kernel", [&] () {
 			xml.attribute("name", "hw");
 			xml.attribute("acpi", true);
+			xml.attribute("msi",  true);
 		});
 		_init_additional_platform_info(xml);
 		xml.node("affinity-space", [&] () {

repos/base-hw/src/core/platform.h

@@ -97,18 +97,22 @@ class Genode::Platform : public Genode::Platform_generic
 		static long irq(long const user_irq);
 
 		/**
-		 * Get MSI-related parameters from device PCI config space
+		 * Allocate MSI exception vector entry
 		 *
-		 * \param mmconf      PCI config space address of device
-		 * \param address     MSI address register value to use
-		 * \param data        MSI data register value to use
-		 * \param irq_number  IRQ to use
+		 * \param address  MSI address register value to use
+		 * \param data     MSI data register value to use
 		 *
-		 * \return  true if the device is MSI-capable, false if not
+		 * \return  true if the platform is MSI-capable, false if not
 		 */
-		static bool get_msi_params(const addr_t mmconf,
-		                           addr_t &address, addr_t &data,
-		                           unsigned &irq_number);
+		static bool alloc_msi_vector(addr_t &address, addr_t &data);
+
+		/**
+		 * Allocate MSI exception vector entry
+		 *
+		 * \param address  MSI address register value to free
+		 * \param data     MSI data register value to free
+		 */
+		static void free_msi_vector(addr_t address, addr_t data);
 
 		static addr_t core_phys_addr(addr_t virt);
 

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

@@ -26,8 +26,7 @@ void Platform::_init_additional_platform_info(Genode::Xml_generator&) { }
 long Platform::irq(long const user_irq) { return user_irq; }
 
 
-bool Platform::get_msi_params(const addr_t /* mmconf */, addr_t & /* address */,
-                              addr_t & /* data */, unsigned & /* irq_number */)
-{
-	return false;
-}
+bool Platform::alloc_msi_vector(addr_t &, addr_t &) { return false; }
+
+
+void Platform::free_msi_vector(addr_t, addr_t) { }

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

@@ -28,6 +28,7 @@ void Platform::_init_additional_platform_info(Genode::Xml_generator&) { }
 long Platform::irq(long const user_irq ) { return user_irq; }
 
 
-bool Platform::get_msi_params(addr_t /* mmconf */, addr_t & /* address */,
-                              addr_t & /* data */, unsigned & /* irq_number */) {
-	return false; }
+bool Platform::alloc_msi_vector(addr_t &, addr_t &) { return false; }
+
+
+void Platform::free_msi_vector(addr_t, addr_t) { }

repos/base-hw/src/core/spec/x86_64/platform_support.cc

@@ -15,6 +15,7 @@
 #include <platform.h>
 #include <kernel/cpu.h>
 #include <map_local.h>
+#include <hw/spec/x86_64/x86_64.h>
 
 using namespace Genode;
 
@@ -60,8 +61,28 @@ void Platform::_init_additional_platform_info(Xml_generator &xml)
 }
 
 
-bool Platform::get_msi_params(addr_t, addr_t &, addr_t &, unsigned &) {
-	return false; }
+Genode::Bit_allocator<64> & msi_allocator()
+{
+	static Genode::Bit_allocator<64> msi_allocator;
+	return msi_allocator;
+}
+
+
+bool Platform::alloc_msi_vector(addr_t & address, addr_t & value)
+{
+	try {
+		address = Hw::Cpu_memory_map::lapic_phys_base();
+		value   = Board::Pic::IPI - 1 - msi_allocator().alloc();
+	return true;
+	} catch(...) {}
+	return false;
+}
+
+
+void Platform::free_msi_vector(addr_t, addr_t value)
+{
+	msi_allocator().free(Board::Pic::IPI - 1 - value);
+}
 
 
 Board::Serial::Serial(addr_t, size_t, unsigned baudrate)