diff --git a/kernel/src/arch/x86_64/pci/mod.rs b/kernel/src/arch/x86_64/pci/mod.rs
index b02c183..872e3a8 100644
--- a/kernel/src/arch/x86_64/pci/mod.rs
+++ b/kernel/src/arch/x86_64/pci/mod.rs
@@ -47,6 +47,7 @@ pub fn init(device_tree: &mut DeviceTree) {
                 pci_info.set_attribute("id", id);
                 pci_info.set_attribute("device", device_info.device);
                 pci_info.set_attribute("vendor", vendor);
+                pci_info.set_attribute("bus", bus);
                 pci_info.set_attribute("class", device_info.full_class.to_string());
                 dev.set_child(pci_info);
                 devices.push((dev_type, dev));
@@ -68,7 +69,8 @@ pub fn check_device(bus: u8, device: u8) -> Option<PciDeviceInfo> {
         return None;
     }
 
-    let reg2 = unsafe { pci_config_read(bus, device, 0, 0x8) };
+    let (reg2, addr) = unsafe { pci_config_read_2(bus, device, 0, 0x8) };
+    log::info!("pci device-({}) addr {} is {}", device, addr, reg2);
     let class = ((reg2 >> 16) & 0x0000_FFFF) as u16;
     let pci_class = PciFullClass::from_u16(class);
     let header_type = get_header_type(bus, device, 0);
@@ -459,9 +461,7 @@ unsafe fn pci_config_read(bus: u8, device: u8, func: u8, offset: u8) -> u32 {
     let func = func as u32;
     let offset = offset as u32;
     // construct address param
-    let address =
-        ((bus << 16) | (device << 11) | (func << 8) | (offset & 0xFC) | 0x8000_0000) as u32;
-
+    let address = (bus << 16) | (device << 11) | (func << 8) | (offset & 0xFC) | 0x8000_0000;
     // write address
     Port::new(0xCF8).write(address);
 
@@ -469,6 +469,20 @@ unsafe fn pci_config_read(bus: u8, device: u8, func: u8, offset: u8) -> u32 {
     Port::new(0xCFC).read()
 }
 
+unsafe fn pci_config_read_2(bus: u8, device: u8, func: u8, offset: u8) -> (u32, u32) {
+    let bus = bus as u32;
+    let device = device as u32;
+    let func = func as u32;
+    let offset = offset as u32;
+    // construct address param
+    let address = (bus << 16) | (device << 11) | (func << 8) | (offset & 0xFC) | 0x8000_0000;
+    // write address
+    Port::new(0xCF8).write(address);
+
+    // read data
+    (Port::new(0xCFC).read(), address)
+}
+
 unsafe fn pci_config_write(bus: u8, device: u8, func: u8, offset: u8, value: u32) {
     let bus = bus as u32;
     let device = device as u32;
diff --git a/sysdata/libraries/pci/src/lib.hb b/sysdata/libraries/pci/src/lib.hb
index 1445fae..431f082 100644
--- a/sysdata/libraries/pci/src/lib.hb
+++ b/sysdata/libraries/pci/src/lib.hb
@@ -1,3 +1,6 @@
+stn := @use("rel:../../stn/src/lib.hb");
+.{string, memory, buffer} := stn
+
 PCIAddress := struct {
 	bus: u8,
 	device: u8,
@@ -13,16 +16,17 @@ scan_bus := fn(): void {
 
 config_read32 := fn(bus: u32, device: u32, func: u32, offset: u32): u32 {
 	// construct address param
-	address := bus << 16 | device << 11 | func << 8
-	address |= offset
-	address &= 0xFC
+	offset_and := offset & 0xFC
+
+	address := bus << 16
+	address |= device << 11
+	address |= func << 8
+	address |= offset_and
 	address |= 0x80000000
 
 	// write address
-	//Port::new(0xCF8).write(address);
+	memory.outl(0xCF8, address)
 
 	// read data
-	//Port::new(0xCFC).read()
-
-	return
+	return memory.inl(0xCFC)
 }
\ No newline at end of file
diff --git a/sysdata/libraries/stn/src/string.hb b/sysdata/libraries/stn/src/string.hb
index e4ba668..97bfb91 100644
--- a/sysdata/libraries/stn/src/string.hb
+++ b/sysdata/libraries/stn/src/string.hb
@@ -3,36 +3,45 @@ length := fn(ptr: ^u8): int {
 	loop if *(ptr + len) == 0 break else len += 1
 	return len
 }
-
 display_int := fn(num: int, p: ^u8): ^u8 {
 	i := 0
 	if num == 0 {
-		*p = 48
+		*p = 48;
+		*(p + 1) = 0
 		return p
 	}
+
+	neg := false
+	if num < 0 {
+		neg = true
+		num = -num
+	}
+
 	loop if num == 0 break else {
 		*(p + i) = num % 10 + 48
 		num /= 10
 		i += 1
 	}
-	@inline(reverse, p);
-	*(p + i) = 0
+
+	if neg {
+		*(p + i) = 45
+		i += 1
+	}
+
+	reverse(p, i)
+
 	return p
 }
 
-reverse := fn(s: ^u8): void {
-	//reverse a string, don't remove digits
-	len := 0
-	loop if *(s + len) == 0 break else len += 1
-	i := 0
-	j := len - 1
-	temp := 0
-	loop if i >= j break else {
-		temp = *(s + i);
-		*(s + i) = *(s + j);
-		*(s + j) = temp
-		i += 1
-		j -= 1
+reverse := fn(p: ^u8, len: int): void {
+	start := 0
+	end := len - 1
+	loop if start >= end break else {
+		temp := *(p + start);
+		*(p + start) = *(p + end);
+		*(p + end) = temp
+		start += 1
+		end -= 1
 	}
 	return
 }
\ No newline at end of file
diff --git a/sysdata/programs/svga_driver/src/main.hb b/sysdata/programs/svga_driver/src/main.hb
index dfd1dd2..f09ed85 100644
--- a/sysdata/programs/svga_driver/src/main.hb
+++ b/sysdata/programs/svga_driver/src/main.hb
@@ -27,6 +27,12 @@ SVGA_disable := fn(): void {
 }
 
 main := fn(): int {
+	a := pci.config_read32(0, 2, 0, 0x8)
+	b := "\0\0\0\0\0\0\0"
+
+	string.display_int(a, b)
+	stn.log.info(b)
+
 	init()
 
 	return 0