pci: msi stuff

src/arch/x86_64/include/arch/pci.h

@@ -3,6 +3,7 @@
 
 #include <stdint.h>
 #include <stddef.h>
+#include <stdbool.h>
 
 #define PCI_DEV_HEADER 0
 #define PCI_BRIDGE_HEADER 1
@@ -85,6 +86,11 @@ static inline void* getbarmemaddr(pci_deviceheader* e, int bar){
 #define PCI_COMMAND_MEMORY 2
 #define PCI_COMMAND_MASTER 4
 
+bool pci_msisupport(pci_enumeration* e);
+void pci_msienable(pci_enumeration* e, bool enable);
+void pci_msimask(pci_enumeration* e, int which, int val);
+void pci_msimaskall(pci_enumeration* e, int val);
+
 void pci_setcommand(pci_enumeration* e, int which, int val);
 pci_enumeration* pci_getdevicecs(int class, int subclass, int n);
 pci_enumeration* pci_getdevicecsp(int class, int subclass, int progif, int n);

src/arch/x86_64/pci.c

@@ -10,6 +10,7 @@ pci_enumeration* enumerations;
 #define CONFIG_DATA 0xCFC
 
 #define COMMAND_REG 1
+#define CAP_MSI 5
 
 pci_enumeration* pci_getdevicecs(int class, int subclass, int n){
 	
@@ -178,6 +179,79 @@ static size_t legacy_getcapabilityoffset(size_t id, pci_enumeration* enumeration
 
 }
 
+bool pci_msisupport(pci_enumeration* e){
+	if(!legacy_getcapabilityoffset(CAP_MSI, e))
+		return false;
+
+	return true;
+}
+
+void pci_msienable(pci_enumeration* e, bool enable){
+	
+	int offset = legacy_getcapabilityoffset(CAP_MSI, e);
+
+	if(!offset)
+		return;
+
+	uint32_t currval = legacy_readdata(e->bus, e->device, e->function, offset);
+
+	if((currval & 1 << 23) == 0)
+		_panic("32 bit MSI not supported!");
+
+	if(enable){
+		currval |= 1 << 16;
+	}
+	else{
+		currval &= ~(1 << 16);
+	}
+
+	legacy_writedata(e->bus, e->device, e->function, offset, currval);
+
+}
+
+void pci_msimask(pci_enumeration* e, int which, int val){
+	int offset = legacy_getcapabilityoffset(CAP_MSI, e);
+
+        if(!offset)
+                return;
+
+	offset += 2;
+
+        uint32_t currval = legacy_readdata(e->bus, e->device, e->function, offset);
+	
+	if(val){
+		currval |= 1 << which;
+	}
+	else{
+		currval &= ~(1 << which);
+	}
+
+	legacy_writedata(e->bus, e->device, e->function, offset, currval);
+
+}
+
+void pci_msimaskall(pci_enumeration* e, int val){
+	
+	int offset = legacy_getcapabilityoffset(CAP_MSI, e);
+
+        if(!offset)
+                return;
+
+        offset += 2;
+
+        uint32_t currval = legacy_readdata(e->bus, e->device, e->function, offset);
+        
+        if(val){
+                currval = 0xFFFFFFFF;
+        }
+        else{
+                currval = 0;
+        }
+
+        legacy_writedata(e->bus, e->device, e->function, offset, currval);
+
+}
+
 static void legacy_enumeratedevice(int bus, int device){
 	
 	// if the device is multifunction, scan and enumerate all 8. else, only one