Make PCI enumeration write more information

The PCI enumeration did, until now, only write a PCI device's address
into the device area. Now, it also writes the class and subclass.
This commit is contained in:
Eric-Paul Ickhorn 2024-07-21 10:26:32 +02:00
parent 6ce831bbeb
commit 4d9b1e390d
Signed by: epickh
GPG Key ID: 1358818BAA38B104
1 changed files with 114 additions and 18 deletions

View File

@ -58,9 +58,11 @@ pci_device_exists:
; Arguments:
; [FURTHEST FROM EBP]
; 3. U32 PCI Device Class & Subclass
; 3. U16 PCI Device Class & Subclass
; (Higher byte: Class, lower byte: Subclass)
; 2. U32 PCI Device Address
; 2. U16 PCI Device Address
; (Higher byte: Bus Address,
; lower byte: Device Address)
; 1. Ptr32 Pointer to PCI driver area of 65536 bytes
; [NEAREST TO EBP]
pci_append_device:
@ -81,19 +83,21 @@ pci_append_device:
.calculate_device_offset:
; Every device slot has 16 bytes, multiply index with 16
shl cx, 4
shl ecx, 4
; Point into driver device area (add device area start on top)
add ecx, ebx
add ecx, PCI_DEVICE_COUNT_OFFSET
mov ebx, ecx
mov ebx, [ebp - 4]
add ebx, PCI_DEVICE_AREA_OFFSET
add ebx, ecx
.set_device:
mov ecx, [ebp - 8]
mov [ebx], ecx
mov ecx, [ebp - 12]
mov [ebx + 4], ecx
mov cx, [ebp - 6]
mov [ebx], cx
mov cx, [ebp - 8]
mov [ebx + 2], cx
increment_device_count:
.increment_device_count:
mov ebx, [ebp - 4]
inc word [ebx + PCI_DEVICE_COUNT_OFFSET]
.epilog:
mov eax, [esi + (64 - 4)]
@ -107,6 +111,68 @@ increment_device_count:
; Arguments:
; [FURTHER FROM EBP]
; 2. U16 Device Number
; 1. U16 Bus Number
; [NEAREST TO EBP]
;
; Returns:
; ax PCI Device Class & Subclass
; (Higher byte: Class, lower byte: Subclass)
pci_get_device_class_at_address:
push dword esi
sub esp, 64
mov esi, esp
mov [esi + (64 - 8)], ebx
mov [esi + (64 - 12)], ecx
mov [esi + (64 - 16)], edx
mov [esi + (64 - 20)], edi
.create_address:
xor eax, eax
; Enable Bit
or al, 1
; Make space for 8 Reserved Bits and 8 Bytes of bus number.
shl eax, 15
; Bus Number
mov al, [ebp - 2]
; Device Number
shl eax, 5 ; Make space for device number
mov dl, [ebp - 4]
and dl, 0x1f
or al, dl
shl eax, 11
; Include the register offset of the configuration space
; register which contains the class and subclass
or eax, 8
.input_output:
mov dx, PCI_CONFIG_ADDRESS_PORT
out dx, eax
mov dx, PCI_CONFIG_DATA_PORT
in eax, dx
; Remove the parts of the register which aren't part of the
; PCI class- and subclass-code
shr eax, 16
.epilog:
mov ebx, [esi + (64 - 8)]
mov ecx, [esi + (64 - 12)]
mov edx, [esi + (64 - 16)]
mov edi, [esi + (64 - 20)]
add esp, 64
pop dword esi
ret
; Arguments:
; [FURTHER FROM EBP]
; 2. U32 Bus Number (0 .. 255)
@ -130,6 +196,8 @@ pci_enumerate_bus:
mov [esi + 4], dword 0
mov eax, [ebp - 8]
mov [esi + 8], eax
mov eax, [ebp - 4]
mov [esi + 12], eax
.initialize_device_loop:
.device_loop:
@ -137,10 +205,12 @@ pci_enumerate_bus:
jae .epilog
.test_whether_device_exists:
push ebp
mov ebp, esp
mov ah, [esi + 8] ; Bus Number
mov al, [esi] ; Device Number
mov [esi + 16], ax
push ebp
mov ebp, esp
call pci_device_exists
mov esp, ebp
pop ebp
@ -148,12 +218,32 @@ pci_enumerate_bus:
cmp ax, 0
je .no_device
.call_append_device:
.append_device:
mov al, [esi + 8]
mov ah, [esi]
; Device Number in DX
xor dx, dx
mov dl, ah
xor ah, ah
push ebp
mov ebp, esp
push dword [esi + 8]
push dword 0xcafebabe
push dword 0xdeadbeef
push ax
push dx
call pci_get_device_class_at_address
mov esp, ebp
pop ebp
mov cx, ax
mov ax, [esi + 16]
push ebp
mov ebp, esp
push dword [esi + 12]
push ax
push cx
call pci_append_device
mov esp, ebp
pop ebp
@ -172,6 +262,7 @@ pci_enumerate_bus:
mov ebx, [esi + (64 - 8)]
mov ecx, [esi + (64 - 12)]
mov edi, [esi + (64 - 20)]
mov eax, [esi + 4]
add esp, 64
@ -203,6 +294,11 @@ pci_enumerate:
mov edx, [ebp - 4]
mov [esi + 4], edx
; Set the device count to 0 explicitly, just for safety.
mov ebx, [ebp - 4]
add ebx, PCI_DEVICE_COUNT_OFFSET
mov [ebx], word 0
.bus_loop:
xor ecx, ecx
mov [esi], dword 0
@ -247,4 +343,4 @@ pci_enumerate:
add esp, 64
pop dword esi
ret
ret