intel_extreme: add MSI support

src/add-ons/kernel/drivers/graphics/intel_extreme/driver.cpp

@@ -103,6 +103,7 @@ int32 api_version = B_CUR_DRIVER_API_VERSION;
 char* gDeviceNames[MAX_CARDS + 1];
 intel_info* gDeviceInfo[MAX_CARDS];
 pci_module_info* gPCI;
+pci_x86_module_info* gPCIx86Module = NULL;
 agp_gart_module_info* gGART;
 mutex gLock;
 
@@ -185,6 +186,14 @@ init_driver(void)
 
 	mutex_init(&gLock, "intel extreme ksync");
 
+	// Try to get the PCI x86 module as well so we can enable possible MSIs.
+	if (get_module(B_PCI_X86_MODULE_NAME,
+			(module_info **)&gPCIx86Module) != B_OK) {
+		ERROR("failed to get pci x86 module\n");
+		gPCIx86Module = NULL;
+	}
+
+
 	// find devices
 
 	int32 found = 0;
@@ -240,6 +249,10 @@ init_driver(void)
 		mutex_destroy(&gLock);
 		put_module(B_AGP_GART_MODULE_NAME);
 		put_module(B_PCI_MODULE_NAME);
+		if (gPCIx86Module != NULL) {
+			gPCIx86Module = NULL;
+			put_module(B_PCI_X86_MODULE_NAME);
+		}
 		return ENODEV;
 	}
 
@@ -263,6 +276,10 @@ uninit_driver(void)
 
 	put_module(B_AGP_GART_MODULE_NAME);
 	put_module(B_PCI_MODULE_NAME);
+	if (gPCIx86Module != NULL) {
+		gPCIx86Module = NULL;
+		put_module(B_PCI_X86_MODULE_NAME);
+	}
 }
 
 

src/add-ons/kernel/drivers/graphics/intel_extreme/driver.h

@@ -20,6 +20,7 @@
 extern char* gDeviceNames[];
 extern intel_info* gDeviceInfo[];
 extern pci_module_info* gPCI;
+extern pci_x86_module_info* gPCIx86Module;
 extern agp_gart_module_info* gGART;
 extern mutex gLock;
 

src/add-ons/kernel/drivers/graphics/intel_extreme/intel_extreme.cpp

@@ -131,13 +131,30 @@ init_interrupt_handler(intel_info &info)
 		status = B_ERROR;
 	}
 
-	if (status == B_OK && info.pci->u.h0.interrupt_pin != 0x00
-		&& info.pci->u.h0.interrupt_line != 0xff) {
+	// Find the right interrupt vector, using MSIs if available.
+	info.irq = 0xff;
+	info.use_msi = false;	
+	if (info.pci->u.h0.interrupt_pin != 0x00)	
+		info.irq = info.pci->u.h0.interrupt_line;
+	if (gPCIx86Module != NULL && gPCIx86Module->get_msi_count(info.pci->bus,
+			info.pci->device, info.pci->function) >= 1) {
+		uint8 msiVector = 0;
+		if (gPCIx86Module->configure_msi(info.pci->bus, info.pci->device,
+				info.pci->function, 1, &msiVector) == B_OK
+			&& gPCIx86Module->enable_msi(info.pci->bus, info.pci->device,
+				info.pci->function) == B_OK) {
+			ERROR("using message signaled interrupts\n");
+			info.irq = msiVector;
+			info.use_msi = true;
+		}
+	}
+
+	if (status == B_OK && info.irq != 0xff) {
 		// we've gotten an interrupt line for us to use
 
 		info.fake_interrupts = false;
 
-		status = install_io_interrupt_handler(info.pci->u.h0.interrupt_line,
+		status = install_io_interrupt_handler(info.irq,
 			&intel_interrupt_handler, (void*)&info, 0);
 		if (status == B_OK) {
 			write32(info, INTEL_DISPLAY_A_PIPE_STATUS,
@@ -384,8 +401,14 @@ intel_extreme_uninit(intel_info &info)
 		write16(info, find_reg(info, INTEL_INTERRUPT_ENABLED), 0);
 		write16(info, find_reg(info, INTEL_INTERRUPT_MASK), ~0);
 
-		remove_io_interrupt_handler(info.pci->u.h0.interrupt_line,
-			intel_interrupt_handler, &info);
+		remove_io_interrupt_handler(info.irq, intel_interrupt_handler, &info);
+
+		if (info.use_msi && gPCIx86Module != NULL) {
+			gPCIx86Module->disable_msi(info.pci->bus,
+				info.pci->device, info.pci->function);
+			gPCIx86Module->unconfigure_msi(info.pci->bus,
+				info.pci->device, info.pci->function);
+		}
 	}
 
 	gGART->unmap_aperture(info.aperture);

src/add-ons/kernel/drivers/graphics/intel_extreme/intel_extreme_private.h

@@ -12,6 +12,7 @@
 #include <AGP.h>
 #include <KernelExport.h>
 #include <PCI.h>
+#include <PCI_x86.h>
 
 #include "intel_extreme.h"
 #include "lock.h"
@@ -34,6 +35,8 @@ struct intel_info {
 	struct overlay_registers* overlay_registers;
 
 	bool			fake_interrupts;
+	uint8			irq;
+	bool			use_msi;
 
 	const char*		device_identifier;
 	DeviceType		device_type;