; USB Host Controller support code: hardware-independent part,
; common for all controller types.
; =============================================================================
; ================================= Constants =================================
; =============================================================================
; USB device must have at least 100ms of stable power before initializing can
; proceed; one timer tick is 10ms, so enforce delay in 10 ticks
USB_CONNECT_DELAY = 10
; USB requires at least 10 ms for reset signalling. Normally, this is one timer
; tick. However, it is possible that we start reset signalling in the end of
; interval between timer ticks and then we test time in the start of the next
; interval; in this case, the delta between [timer_ticks] is 1, but the real
; time passed is significantly less than 10 ms. To avoid this, we add an extra
; tick; this guarantees that at least 10 ms have passed.
USB_RESET_TIME = 2
; USB requires at least 10 ms of reset recovery, a delay between reset
; signalling and any commands to device. Add an extra tick for the same reasons
; as with the previous constant.
USB_RESET_RECOVERY_TIME = 2
; =============================================================================
; ================================ Structures =================================
; =============================================================================
; Controller descriptor.
; This structure represents the common (controller-independent) part
; of a controller for the USB code. The corresponding controller-dependent
; part *hci_controller is located immediately before usb_controller.
struct usb_controller
; Two following fields organize all controllers in the global linked list.
Next dd ?
Prev dd ?
HardwareFunc dd ?
; Pointer to usb_hardware_func structure with controller-specific functions.
NumPorts dd ?
; Number of ports in the root hub.
SetAddressBuffer rb 8
; Buffer for USB control command SET_ADDRESS.
ExistingAddresses rd 128/32
; Bitmask for 128 bits; bit i is cleared <=> address i is free for allocating
; for new devices. Bit 0 is always set.
;
; The hardware is allowed to cache some data from hardware structures.
; Regular operations are designed considering this,
; but sometimes it is required to wait for synchronization of hardware cache
; with modified structures in memory.
; The code keeps two queues of pipes waiting for synchronization,
; one for asynchronous (bulk/control) pipes, one for periodic pipes, hardware
; cache is invalidated under different conditions for those types.
; Both queues are organized in the same way, as single-linked lists.
; There are three special positions: the head of list (new pipes are added
; here), the first pipe to be synchronized at the current iteration,
; the tail of list (all pipes starting from here are synchronized).
WaitPipeListAsync dd ?
WaitPipeListPeriodic dd ?
; List heads.
WaitPipeRequestAsync dd ?
WaitPipeRequestPeriodic dd ?
; Pending request to hardware to refresh cache for items from WaitPipeList*.
; (Pointers to some items in WaitPipeList* or NULLs).
ReadyPipeHeadAsync dd ?
ReadyPipeHeadPeriodic dd ?
; Items of RemovingList* which were released by hardware and are ready
; for further processing.
; (Pointers to some items in WaitPipeList* or NULLs).
NewConnected dd ?
; bit mask of recently connected ports of the root hub,
; bit set = a device was recently connected to the corresponding port;
; after USB_CONNECT_DELAY ticks of stable status these ports are moved to
; PendingPorts
NewDisconnected dd ?
; bit mask of disconnected ports of the root hub,
; bit set = a device in the corresponding port was disconnected,
; disconnect processing is required.
PendingPorts dd ?
; bit mask of ports which are ready to be initialized
ControlLock MUTEX ?
; mutex which guards all operations with control queue
BulkLock MUTEX ?
; mutex which guards all operations with bulk queue
PeriodicLock MUTEX ?
; mutex which guards all operations with periodic queues
WaitSpinlock:
; spinlock guarding WaitPipeRequest/ReadyPipeHead (but not WaitPipeList)
StartWaitFrame dd ?
; USB frame number when WaitPipeRequest* was registered.
ResettingHub dd ?
; Pointer to usb_hub responsible for the currently resetting port, if any.
; NULL for the root hub.
ResettingPort db ?
; Port that is currently resetting, 0-based.
ResettingSpeed db ?
; Speed of currently resetting device.
ResettingStatus db ?
; Status of port reset. 0 = no port is resetting, -1 = reset failed,
; 1 = reset in progress, 2 = reset recovery in progress.
rb 1 ; alignment
ResetTime dd ?
; Time when reset signalling or reset recovery has been started.
ConnectedTime rd 16
; Time, in timer ticks, when the port i has signalled the connect event.
; Valid only if bit i in NewConnected is set.
DevicesByPort rd 16
; Pointer to usb_pipe for zero endpoint (which serves as device handle)
; for each port.
ends
; Interface-specific data. Several interfaces of one device can operate
; independently, each is controlled by some driver and is identified by
; some driver-specific data passed as is to the driver.
struct usb_interface_data
DriverData dd ?
; Passed as is to the driver.
DriverFunc dd ?
; Pointer to USBSRV structure for the driver.
ends
; Device-specific data.
struct usb_device_data
PipeListLock MUTEX
; Lock guarding OpenedPipeList. Must be the first item of the structure,
; the code passes pointer to usb_device_data as is to mutex_lock/unlock.
OpenedPipeList rd 2
; List of all opened pipes for the device.
; Used when the device is disconnected, so all pipes should be closed.
ClosedPipeList rd 2
; List of all closed, but still valid pipes for the device.
; A pipe closed with USBClosePipe is just deallocated,
; but a pipe closed due to disconnect must remain valid until driver-provided
; disconnect handler returns; this list links all such pipes to deallocate them
; after disconnect processing.
NumPipes dd ?
; Number of not-yet-closed pipes.
Hub dd ?
; NULL if connected to the root hub, pointer to usb_hub otherwise.
Port db ?
; Port on the hub, zero-based.
DeviceDescrSize db ?
; Size of device descriptor.
NumInterfaces db ?
; Number of interfaces.
Speed db ?
; Device speed, one of USB_SPEED_*.
ConfigDataSize dd ?
; Total size of data associated with the configuration descriptor
; (including the configuration descriptor itself);
Interfaces dd ?
; Offset from the beginning of this structure to Interfaces field.
; Variable-length fields:
; DeviceDescriptor:
; device descriptor starts here
; ConfigDescriptor = DeviceDescriptor + DeviceDescrSize
; configuration descriptor with all associated data
; Interfaces = ALIGN_UP(ConfigDescriptor + ConfigDataSize, 4)
; array of NumInterfaces elements of type usb_interface_data
ends
usb_device_data.DeviceDescriptor = sizeof.usb_device_data
; Description of controller-specific data and functions.
struct usb_hardware_func
ID dd ? ; '*HCI'
DataSize dd ? ; sizeof(*hci_controller)
Init dd ?
; Initialize controller-specific part of controller data.
; in: eax -> *hci_controller to initialize, [ebp-4] = (bus shl 8) + devfn
; out: eax = 0 <=> failed, otherwise eax -> usb_controller
ProcessDeferred dd ?
; Called regularly from the main loop of USB thread
; (either due to timeout from a previous call, or due to explicit wakeup).
; in: esi -> usb_controller
; out: eax = maximum timeout for next call (-1 = infinity)
SetDeviceAddress dd ?
; in: esi -> usb_controller, ebx -> usb_pipe, cl = address
GetDeviceAddress dd ?
; in: esi -> usb_controller, ebx -> usb_pipe
; out: eax = address
PortDisable dd ?
; Disable the given port in the root hub.
; in: esi -> usb_controller, ecx = port (zero-based)
InitiateReset dd ?
; Start reset signalling on the given port.
; in: esi -> usb_controller, ecx = port (zero-based)
SetEndpointPacketSize dd ?
; in: esi -> usb_controller, ebx -> usb_pipe, ecx = packet size
AllocPipe dd ?
; out: eax = pointer to allocated usb_pipe
FreePipe dd ?
; void stdcall with one argument = pointer to previously allocated usb_pipe
InitPipe dd ?
; in: edi -> usb_pipe for target, ecx -> usb_pipe for config pipe,
; esi -> usb_controller, eax -> usb_gtd for the first TD,
; [ebp+12] = endpoint, [ebp+16] = maxpacket, [ebp+20] = type
UnlinkPipe dd ?
; esi -> usb_controller, ebx -> usb_pipe
AllocTD dd ?
; out: eax = pointer to allocated usb_gtd
FreeTD dd ?
; void stdcall with one argument = pointer to previously allocated usb_gtd
AllocTransfer dd ?
; Allocate and initialize one stage of a transfer.
; ebx -> usb_pipe, other parameters are passed through the stack:
; buffer,size = data to transfer
; flags = same as in usb_open_pipe:
; bit 0 = allow short transfer, other bits reserved
; td = pointer to the current end-of-queue descriptor
; direction =
; 0000b for normal transfers,
; 1000b for control SETUP transfer,
; 1101b for control OUT transfer,
; 1110b for control IN transfer
; returns eax = pointer to the new end-of-queue descriptor
; (not included in the queue itself) or 0 on error
InsertTransfer dd ?
; Activate previously initialized transfer (maybe with multiple stages).
; esi -> usb_controller, ebx -> usb_pipe,
; [esp+4] -> first usb_gtd for the transfer,
; ecx -> last descriptor for the transfer
NewDevice dd ?
; Initiate configuration of a new device (create pseudo-pipe describing that
; device and call usb_new_device).
; esi -> usb_controller, eax = speed (one of USB_SPEED_* constants).
ends
; =============================================================================
; =================================== Code ====================================
; =============================================================================
; Initializes one controller, called by usb_init for every controller.
; edi -> usb_hardware_func, eax -> PCIDEV structure for the device.
proc usb_init_controller
push ebp
mov ebp, esp
; 1. Store in the stack PCI coordinates and save pointer to PCIDEV:
; make [ebp-4] = (bus shl 8) + devfn, used by controller-specific Init funcs.
push dword [eax+PCIDEV.devfn]
push eax
; 2. Allocate *hci_controller + usb_controller.
mov ebx, [edi+usb_hardware_func.DataSize]
add ebx, sizeof.usb_controller
stdcall kernel_alloc, ebx
test eax, eax
jz .nothing
; 3. Zero-initialize both structures.
push edi eax
mov ecx, ebx
shr ecx, 2
xchg edi, eax
xor eax, eax
rep stosd
; 4. Initialize usb_controller structure,
; except data known only to controller-specific code (like NumPorts)
; and link fields
; (this structure will be inserted to the overall list at step 6).
dec eax
mov [edi+usb_controller.ExistingAddresses+4-sizeof.usb_controller], eax
mov [edi+usb_controller.ExistingAddresses+8-sizeof.usb_controller], eax
mov [edi+usb_controller.ExistingAddresses+12-sizeof.usb_controller], eax
mov [edi+usb_controller.ResettingPort-sizeof.usb_controller], al ; no resetting port
dec eax ; don't allocate zero address
mov [edi+usb_controller.ExistingAddresses-sizeof.usb_controller], eax
lea ecx, [edi+usb_controller.PeriodicLock-sizeof.usb_controller]
call mutex_init
add ecx, usb_controller.ControlLock - usb_controller.PeriodicLock
call mutex_init
add ecx, usb_controller.BulkLock - usb_controller.ControlLock
call mutex_init
pop eax edi
mov [eax+ebx-sizeof.usb_controller+usb_controller.HardwareFunc], edi
push eax
; 5. Call controller-specific initialization.
; If failed, free memory allocated in step 2 and return.
call [edi+usb_hardware_func.Init]
test eax, eax
jz .fail
pop ecx
; 6. Insert the controller to the global list.
xchg eax, ebx
mov ecx, usb_controllers_list_mutex
call mutex_lock
mov edx, usb_controllers_list
mov eax, [edx+usb_controller.Prev]
mov [ebx+usb_controller.Next], edx
mov [ebx+usb_controller.Prev], eax
mov [edx+usb_controller.Prev], ebx
mov [eax+usb_controller.Next], ebx
call mutex_unlock
; 7. Wakeup USB thread to call ProcessDeferred.
call usb_wakeup
.nothing:
; 8. Restore pointer to PCIDEV saved in step 1 and return.
pop eax
leave
ret
.fail:
call kernel_free
jmp .nothing
endp
; Helper function, calculates physical address including offset in page.
proc get_phys_addr
push ecx
mov ecx, eax
and ecx, 0xFFF
call get_pg_addr
add eax, ecx
pop ecx
ret
endp
; Put the given control pipe in the wait list;
; called when the pipe structure is changed and a possible hardware cache
; needs to be synchronized. When it will be known that the cache is updated,
; usb_subscription_done procedure will be called.
proc usb_subscribe_control
cmp [ebx+usb_pipe.NextWait], -1
jnz @f
mov eax, [esi+usb_controller.WaitPipeListAsync]
mov [ebx+usb_pipe.NextWait], eax
mov [esi+usb_controller.WaitPipeListAsync], ebx
@@:
ret
endp
; Called after synchronization of hardware cache with software changes.
; Continues process of device enumeration based on when it was delayed
; due to call to usb_subscribe_control.
proc usb_subscription_done
mov eax, [ebx+usb_pipe.DeviceData]
cmp [eax+usb_device_data.DeviceDescrSize], 0
jz usb_after_set_address
jmp usb_after_set_endpoint_size
endp
; This function is called when a new device has either passed
; or failed first stages of configuration, so the next device
; can enter configuration process.
proc usb_test_pending_port
mov [esi+usb_controller.ResettingPort], -1
cmp [esi+usb_controller.PendingPorts], 0
jz .nothing
bsf ecx, [esi+usb_controller.PendingPorts]
btr [esi+usb_controller.PendingPorts], ecx
mov eax, [esi+usb_controller.HardwareFunc]
jmp [eax+usb_hardware_func.InitiateReset]
.nothing:
ret
endp
; This procedure is regularly called from controller-specific ProcessDeferred,
; it checks whether there are disconnected events and if so, process them.
proc usb_disconnect_stage2
bsf ecx, [esi+usb_controller.NewDisconnected]
jz .nothing
lock btr [esi+usb_controller.NewDisconnected], ecx
btr [esi+usb_controller.PendingPorts], ecx
xor ebx, ebx
xchg ebx, [esi+usb_controller.DevicesByPort+ecx*4]
test ebx, ebx
jz usb_disconnect_stage2
call usb_device_disconnected
jmp usb_disconnect_stage2
.nothing:
ret
endp
; Initial stage of disconnect processing: called when device is disconnected.
proc usb_device_disconnected
; Loop over all pipes, close everything, wait until hardware reacts.
; The final handling is done in usb_pipe_closed.
push ebx
mov ecx, [ebx+usb_pipe.DeviceData]
call mutex_lock
lea eax, [ecx+usb_device_data.OpenedPipeList-usb_pipe.NextSibling]
push eax
mov ebx, [eax+usb_pipe.NextSibling]
.pipe_loop:
call usb_close_pipe_nolock
mov ebx, [ebx+usb_pipe.NextSibling]
cmp ebx, [esp]
jnz .pipe_loop
pop eax
pop ebx
mov ecx, [ebx+usb_pipe.DeviceData]
call mutex_unlock
ret
endp
; Called from controller-specific ProcessDeferred,
; processes wait-pipe-done notifications,
; returns whether there are more items in wait queues.
; in: esi -> usb_controller
; out: eax = bitmask of pipe types with non-empty wait queue
proc usb_process_wait_lists
xor edx, edx
push edx
call usb_process_one_wait_list
jnc @f
or byte [esp], 1 shl CONTROL_PIPE
@@:
push 4
pop edx
call usb_process_one_wait_list
jnc @f
or byte [esp], 1 shl INTERRUPT_PIPE
@@:
xor edx, edx
call usb_process_one_wait_list
jnc @f
or byte [esp], 1 shl CONTROL_PIPE
@@:
pop eax
ret
endp
; Helper procedure for usb_process_wait_lists;
; does the same for one wait queue.
; in: esi -> usb_controller,
; edx=0 for *Async, edx=4 for *Periodic list
; out: CF = issue new request
proc usb_process_one_wait_list
; 1. Check whether there is a pending request. If so, do nothing.
mov ebx, [esi+usb_controller.WaitPipeRequestAsync+edx]
cmp ebx, [esi+usb_controller.ReadyPipeHeadAsync+edx]
clc
jnz .nothing
; 2. Check whether there are new data. If so, issue a new request.
cmp ebx, [esi+usb_controller.WaitPipeListAsync+edx]
stc
jnz .nothing
test ebx, ebx
jz .nothing
; 3. Clear all lists.
xor ecx, ecx
mov [esi+usb_controller.WaitPipeListAsync+edx], ecx
mov [esi+usb_controller.WaitPipeRequestAsync+edx], ecx
mov [esi+usb_controller.ReadyPipeHeadAsync+edx], ecx
; 4. Loop over all pipes from the wait list.
.pipe_loop:
; For every pipe:
; 5. Save edx and next pipe in the list.
push edx
push [ebx+usb_pipe.NextWait]
; 6. If USB_FLAG_EXTRA_WAIT is set, reinsert the pipe to the list and continue.
test [ebx+usb_pipe.Flags], USB_FLAG_EXTRA_WAIT
jz .process
mov eax, [esi+usb_controller.WaitPipeListAsync+edx]
mov [ebx+usb_pipe.NextWait], eax
mov [esi+usb_controller.WaitPipeListAsync+edx], ebx
jmp .continue
.process:
; 7. Call the handler depending on USB_FLAG_CLOSED.
or [ebx+usb_pipe.NextWait], -1
test [ebx+usb_pipe.Flags], USB_FLAG_CLOSED
jz .nodisconnect
call usb_pipe_closed
jmp .continue
.nodisconnect:
call usb_subscription_done
.continue:
; 8. Restore edx and next pipe saved in step 5 and continue the loop.
pop ebx
pop edx
test ebx, ebx
jnz .pipe_loop
.check_new_work:
; 9. Set CF depending on whether WaitPipeList* is nonzero.
cmp [esi+usb_controller.WaitPipeListAsync+edx], 1
cmc
.nothing:
ret
endp