From 168f9ebb621e73ac1ccedd4270a1e55d705101a7 Mon Sep 17 00:00:00 2001
From: Greg Bowne <gbowne144@gmail.com>
Date: Wed, 18 Oct 2023 19:15:44 -0700
Subject: [PATCH] Moar fixes to pci.c and pci.h

---
 CMakeLists.txt        | 11 +++++++++--
 src/boot/boot.asm     |  4 +++-
 src/drivers/bus/pci.c | 32 ++++++++++++++++++++++++++++----
 src/drivers/bus/pci.h |  3 +--
 4 files changed, 41 insertions(+), 9 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7bce36f..ba263ac 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,15 +1,21 @@
 cmake_minimum_required(VERSION 3.13.4)
-project(ClassicOS VERSION 0.0.1 LANGUAGES C)
+project(ClassicOS
+		VERSION 0.0.1
+		DESCRIPTION "An x86 Operating System for your pleasure and enjoyment"
+        HOMEPAGE_URL "https://github.com/gbowne1/ClassicOS"
+		LANGUAGES C ASM_NASM)
 
 # Source files
 set(BOOT_SOURCE_FILES
     src/boot/boot.asm
     src/boot/linker.ld
 )
+
 set(GRUB_SOURCE_FILES
     src/boot/grub/grub.cfg
     src/boot/grub/menu.lst
 )
+
 set(DRIVERS_SOURCE_FILES
     src/drivers/audio/audio.c
     src/drivers/audio/audio.h
@@ -53,7 +59,7 @@ set(KERNEL_SOURCE_FILES
 
 add_executable(ClassicOS
     ${BOOT_SOURCE_FILES}
-    ${GRUB_SOURCE_FILES}
+	${GRUB_SOURCE_FILES}
     ${DRIVERS_SOURCE_FILES}
     ${KERNEL_SOURCE_FILES}
 )
@@ -78,6 +84,7 @@ set(CMAKE_CXX_FLAGS_DEBUG "-g -O0")
 set(CMAKE_CXX_COMPILER g++)
 set(CMAKE_ASM_COMPILER nasm)
 set(CMAKE_ASM_FLAGS "${CMAKE_ASM_FLAGS} --32")
+set(CMAKE_ASM_NASM_OBJECT_FORMAT bin)
 set(CMAKE_SYSTEM_PROCESSOR i386)
 set(CMAKE_SYSTEM_NAME None)
 set(CMAKE_ASM_NASM_COMPILER nasm)
diff --git a/src/boot/boot.asm b/src/boot/boot.asm
index f652fef..51a73e5 100644
--- a/src/boot/boot.asm
+++ b/src/boot/boot.asm
@@ -1,3 +1,5 @@
+[BITS 16]
+
 ; Set up the segment registers
 xor ax, ax
 mov ds, ax
@@ -89,7 +91,7 @@ main:
    ; Wait for a key press to exit the loop
    mov ah, 0x00
    int 0x16
-   
+
    ; Call the detect_disk function
    call detect_disk
 
diff --git a/src/drivers/bus/pci.c b/src/drivers/bus/pci.c
index 3ae3492..073237e 100644
--- a/src/drivers/bus/pci.c
+++ b/src/drivers/bus/pci.c
@@ -16,18 +16,42 @@
 // Initialize the PCI bus
 void pci_init()
 {
-    // Add any necessary initialization code here
+    // Enable PCI bus master
+    pci_write(PCI_COMMAND_PORT, 0x04);
 }
 
 // Detect and configure PCI devices
 void pci_detect_devices()
 {
-    // Add any necessary device detection and configuration code here
+    // Scan all PCI buses and devices
+    for (int bus = 0; bus < 256; bus++) {
+        for (int device = 0; device < 32; device++) {
+            for (int function = 0; function < 8; function++) {
+                uint16_t vendor_id = pci_read(bus, device, function, 0x00);
+                if (vendor_id != 0xFFFF) {
+                    uint16_t device_id = pci_read(bus, device, function, 0x02);
+                    uint8_t class_code = pci_read(bus, device, function, 0x0B);
+                    uint8_t subclass_code = pci_read(bus, device, function, 0x0A);
+                    uint8_t prog_if = pci_read(bus, device, function, 0x09);
+                    uint8_t header_type = pci_read(bus, device, function, 0x0E);
+                    uint8_t irq_line = pci_read(bus, device, function, 0x3C);
+                    uint32_t bar0 = pci_read(bus, device, function, 0x10);
+                    uint32_t bar1 = pci_read(bus, device, function, 0x14);
+                    uint32_t bar2 = pci_read(bus, device, function, 0x18);
+                    uint32_t bar3 = pci_read(bus, device, function, 0x1C);
+                    uint32_t bar4 = pci_read(bus, device, function, 0x20);
+                    uint32_t bar5 = pci_read(bus, device, function, 0x24);
+                    // Add any necessary device detection and configuration code here
+                }
+            }
+        }
+    }
 }
 
 // Read from a PCI device
-uint8_t pci_read(uint16_t port)
+uint8_t pci_read(uint8_t bus, uint8_t device, uint8_t function, uint8_t offset)
 {
+    uint16_t port = PCI_BASE_ADDRESS | ((uint16_t)bus << 8) | ((uint16_t)device << 3) | ((uint16_t)function << 0x0B) | ((uint16_t)offset & 0xFC);
     uint8_t value;
 
     // Read from the specified port
@@ -41,4 +65,4 @@ void pci_write(uint16_t port, uint8_t value)
 {
     // Write the specified value to the specified port
     __asm__ volatile("outb %0, %1" : : "a"(value), "dN"(port));
-}
\ No newline at end of file
+}
diff --git a/src/drivers/bus/pci.h b/src/drivers/bus/pci.h
index 7ecc598..c891231 100644
--- a/src/drivers/bus/pci.h
+++ b/src/drivers/bus/pci.h
@@ -11,8 +11,7 @@ void pci_init();
 // Detect and configure PCI devices
 void pci_detect_devices();
 
-// Read from a PCI device
-uint8_t pci_read(uint16_t port);
+uint8_t pci_read(uint8_t bus, uint8_t device, uint8_t function, uint8_t offset);
 
 // Write to a PCI device
 void pci_write(uint16_t port, uint8_t value);