Merge branch 'pci_enum' into 'master'

Pci enum

Just writes all the PCI devices to serial

See merge request !16

src/asm.h

@@ -2,7 +2,8 @@
   asm.h contains x86 specific functions for executing low level code
 */
 
-#pragma once
+#ifndef _ASM_INC
+#define _ASM_INC
 #include <stdint.h>
 
 // Wrapper for outb
@@ -20,6 +21,20 @@ inline uint8_t inb(uint16_t port)
     return ret;
 }
 
+// Wrapper for outl
+inline void outl(uint16_t port, uint32_t val)
+{
+    asm volatile("outl %0, %1" : : "a"(val), "Nd"(port));
+}
+
+// Wrapper for inl
+inline uint32_t inl(uint16_t port)
+{
+    uint32_t ret;
+    asm volatile ("inl %1, %0" : "=a"(ret) : "Nd"(port));
+    return ret;
+}
+
 inline void disable_int()
 {
     asm volatile ("cli");
@@ -29,3 +44,5 @@ inline void enable_int()
 {
     asm volatile ("sti");
 }
+
+#endif

src/kern.c

@@ -14,6 +14,7 @@
 #include "gdt.h"
 #include "idt.h"
 #include "test.h"
+#include "pci.h"
 #include "multiboot.h"
 #include "pic.h"
 #include "pit.h"
@@ -61,7 +62,12 @@ void kernel_main(multiboot_info* mbt, uint32_t magic)
     int o=0;
     int j=5/o;
     serial_hexword(j);
-    test_mem();
+    //test_mem();
+    serial_writechar('\n');
+
+    // PCI
+    checkAllBuses();
+
     test_idt();
     while(true)
     {

src/makefile

@@ -9,3 +9,8 @@ all:
 
 clean:
 	rm *.o *.bin
+run:
+	qemu-system-i386 -kernel myos.bin -serial file:serial.log -hda /dev/null \
+	-drive file=/dev/null,if=none,id=drive-sata0-0-0 \
+	-device ich9-ahci,id=ahci \
+	-device ide-drive,drive=drive-sata0-0-0,bus=ahci.0 \

src/pci.c

+// pci.c
+//
+// Contains implementations of the functions for dealing with PCI
+// defined in pci.h
+
+#include "pci.h"
+#include "serial.h"
+
+void pciSerialInfo(uint8_t bus, uint8_t device, uint8_t function, uint8_t offset)
+{
+    uint32_t address;
+    uint32_t lbus  = (uint32_t)bus;
+    uint32_t lslot = (uint32_t)device;
+    uint32_t lfunc = (uint32_t)function;
+    address = (uint32_t)((lbus << 16) |
+                         (lslot << 11) |
+                         (lfunc << 8) |
+                         (offset & 0xfc) |
+                         ((uint32_t)0x80000000));
+    outl(PCI_CONFIG_ACCESS, address);
+
+    uint32_t data = inl(PCI_CONFIG_DATA);
+
+    serial_writestring("address 0x");
+    serial_hexword(address);
+    serial_writestring(" returned 0x");
+    serial_hexword(data);
+    serial_writestring(" on bus ");
+    serial_hexbyte(bus);
+    serial_writestring(" device ");
+    serial_hexbyte(device);
+    serial_writestring(" function ");
+    serial_hexbyte(function);
+    serial_writestring(" with offset ");
+    serial_hexbyte(offset);
+    serial_writechar('\n');
+}
+
+// reads a word from the io port using the pci addressing scheme
+uint32_t pciConfigReadWord(uint8_t bus, uint8_t device, uint8_t func, uint8_t offset)
+{
+    uint32_t address;
+    uint32_t lbus  = (uint32_t)bus;
+    uint32_t ldev = (uint32_t)device;
+    uint32_t lfunc = (uint32_t)func;
+
+    address = (uint32_t)((lbus << 16) |
+                         (ldev << 11) |
+                         (lfunc << 8) |
+                         (offset & 0xfc) |
+                         ((uint32_t)0x80000000));
+    outl(PCI_CONFIG_ACCESS, address);
+
+    // return the contents of the address clipped
+    uint32_t data = inl(PCI_CONFIG_DATA);
+    return data;
+}
+
+void checkAllBuses(void)
+{
+    serial_writestring("Enumerating PCI busses\n");
+    uint8_t bus;
+    uint8_t device;
+    uint8_t function;
+
+    for (bus = 0; bus < 255; bus++)
+    {
+        for (device = 0; device < 32; device++)
+        {
+            for (function = 0; function < 8; function++)
+            {
+                if (pciConfigReadWord(bus, device, function, 0) != 0xffffffff)
+                {
+                    pciSerialInfo(bus, device, function, 0);
+                    serial_writestring("- - - - - - - - - - - - - - - - - - - -\n");
+                    pciSerialInfo(bus, device, function, 8);
+                    serial_writestring("=======================================\n");
+                }
+            }
+        }
+    }
+}

src/pci.h

+// pci.h
+//
+// Contains headers for functions related to dealivg with PCI
+
+#ifndef _PCI_INC
+#define _PCI_INC
+
+#include <stdint.h>
+
+#include "asm.h"
+
+#define PCI_CONFIG_ACCESS 0xCF8
+#define PCI_CONFIG_DATA 0xCFC
+
+uint32_t pciConfigReadWord(uint8_t bus, uint8_t slot, uint8_t func, uint8_t offset);
+
+void checkAllBuses();
+
+
+#endif

src/serial.c

@@ -39,6 +39,22 @@ void serial_writestring(char* s)
 }
 
 const char* hexchars = "0123456789abcdef";
+void serial_hexbyte(uint8_t x)
+{
+    for (int i = 1; i >= 0; i--)
+    {
+        serial_writechar(hexchars[x>>i*4&0xf]);
+    }
+}
+
+void serial_hexhword(uint16_t x)
+{
+    for (int i = 3; i >= 0; i--)
+    {
+        serial_writechar(hexchars[x>>i*4&0xf]);
+    }
+}
+
 void serial_hexword(uint32_t x)
 {
     for (int i = 7; i >= 0; i--)

src/serial.h

@@ -21,8 +21,12 @@ void serial_writechar(char a);
 void serial_writestring(char* s);
 
 // Function to write a 4 byte word toserial in hex
+void serial_hexbyte(uint8_t x);
+void serial_hexhword(uint16_t x);
 void serial_hexword(uint32_t x);
 void serial_hexqword(uint64_t x);
+
+// Writes an arbitrary amount memory to serial
 void serial_hexstring(void* s, uint32_t n);
 
 #endif