74,6 → 74,14 |
cmp al,10 |
jz pci_write_reg ;dword |
|
cmp al,11 ; <<< user-level MMIO functions <<< NEW! |
jz pci_mmio_init |
cmp al,12 |
jz pci_mmio_map |
cmp al,13 |
jz pci_mmio_unmap |
|
|
no_pci_access_for_applications: |
|
mov eax,-1 |
366,6 → 374,139 |
dec eax |
ret |
|
;*************************************************************************** |
; Function |
; pci_mmio_init ; NEW! |
; |
; Description |
; IN: bx = device's PCI bus address (bbbbbbbbdddddfff) |
; returns ax = user heap space available (bytes) |
; Error codes |
; eax = -1 : PCI user access blocked, |
; eax = -2 : device not registered for uMMIO service |
; eax = -3 : user heap initialization failure |
;*************************************************************************** |
align 4 |
pci_mmio_init: |
cmp bx, word [mmio_pci_addr] ; must be set in kernel/data32.inc |
jz @f |
mov eax,-2 |
ret |
@@: |
call init_heap ; (if not initialized yet) |
or eax,eax |
jz @f |
ret |
@@: |
mov eax,-3 |
ret |
|
|
;*************************************************************************** |
; Function |
; pci_mmio_map ; NEW! |
; |
; Description |
; maps a block of PCI memory to user-accessible linear address |
; |
; WARNING! This VERY EXPERIMENTAL service is for one chosen PCI device only! |
; The target device address should be set in kernel var mmio_pci_addr |
; |
; IN: ah = BAR#; |
; IN: ebx = block size (bytes); |
; IN: ecx = offset in MMIO block (in 4K-pages, to avoid misaligned pages); |
; |
; Returns eax = MMIO block's linear address in the userspace (if no error) |
; |
; |
; Error codes |
; eax = -1 : user access to PCI blocked, |
; eax = -2 : an invalid BAR register referred |
; eax = -3 : no i/o space on that BAR |
; eax = -4 : a port i/o BAR register referred |
; eax = -5 : dynamic userspace allocation problem |
;*************************************************************************** |
|
align 4 |
pci_mmio_map: |
and edx,0x0ffff |
cmp ah,6 |
jc @f |
mov eax,-2 |
ret |
@@: |
push ecx |
add ebx, 4095 |
and ebx,-4096 |
push ebx |
mov bl, ah ; bl = BAR# (0..5) |
shl bl, 1 |
shl bl, 1 |
add bl, 0x10 ; bl = BARs offset in PCI config. space |
mov ax,word [mmio_pci_addr] |
mov bh, al ; bh = dddddfff |
mov al, 2 ; al : DW to read |
call pci_read_reg |
or eax, eax |
jnz @f |
mov eax,-3 ; empty I/O space |
jmp mmio_ret_fail |
@@: |
test eax, 1 |
jz @f |
mov eax,-4 ; damned ports (not MMIO space) |
jmp mmio_ret_fail |
@@: |
pop ecx ; ecx = block size, bytes (expanded to whole page) |
mov ebx, ecx ; user_alloc destroys eax, ecx, edx, but saves ebx |
push eax ; store MMIO physical address + keep 2DWords in the stack |
stdcall user_alloc, ecx |
or eax, eax |
jnz mmio_map_over |
mov eax,-5 ; problem with page allocation |
|
mmio_ret_fail: |
pop ecx |
pop edx |
ret |
|
mmio_map_over: |
mov ecx, ebx ; ecx = size (bytes, expanded to whole page) |
shr ecx, 12 ; ecx = number of pages |
mov ebx, eax ; ebx = linear address |
pop eax ; eax = MMIO start |
pop edx ; edx = MMIO shift (pages) |
shl edx, 12 ; edx = MMIO shift (bytes) |
add eax, edx ; eax = uMMIO physical address |
or eax, PG_SHARED |
or eax, PG_UW |
or eax, PG_NOCACHE |
mov edi, ebx |
call commit_pages |
mov eax, edi |
ret |
|
;*************************************************************************** |
; Function |
; pci_mmio_unmap_page ; NEW! |
; |
; Description |
; unmaps the linear space previously tied to a PCI memory block |
; |
; IN: ebx = linear address of space previously allocated by pci_mmio_map |
; returns eax = 1 if successfully unmapped |
; |
; Error codes |
; eax = -1 if no user PCI access allowed, |
; eax = 0 if unmapping failed |
;*************************************************************************** |
|
align 4 |
pci_mmio_unmap: |
stdcall user_free, ebx |
ret |
|
|
;-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= |
|
; VendID (2), DevID (2), Revision = 0 (1), Class Code (3), FNum (1), Bus (1) |