1088 lines
40 KiB
PHP
1088 lines
40 KiB
PHP
; Implementation of periodic transaction scheduler for USB.
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; Bandwidth dedicated to periodic transactions is limited, so
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; different pipes should be scheduled as uniformly as possible.
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; USB1 scheduler.
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; Algorithm is simple:
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; when adding a pipe, optimize the following quantity:
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; * for every millisecond, take all bandwidth scheduled to periodic transfers,
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; * calculate maximum over all milliseconds,
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; * select a variant which minimizes that maximum;
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; when removing a pipe, do nothing (except for bookkeeping).
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; sanity check: structures in UHCI and OHCI should be the same
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if (sizeof.ohci_static_ep=sizeof.uhci_static_ep)&(ohci_static_ep.SoftwarePart=uhci_static_ep.SoftwarePart)&(ohci_static_ep.NextList=uhci_static_ep.NextList)
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; Select a list for a new pipe.
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; in: esi -> usb_controller, maxpacket, type, interval can be found in the stack
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; in: ecx = 2 * maximal interval = total number of periodic lists + 1
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; in: edx -> {u|o}hci_static_ep for the first list
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; in: eax -> byte past {u|o}hci_static_ep for the last list in the first group
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; out: edx -> usb_static_ep for the selected list or zero if failed
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proc usb1_select_interrupt_list
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; inherit some variables from usb_open_pipe
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virtual at ebp-12
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.speed db ?
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rb 3
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.bandwidth dd ?
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.target dd ?
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dd ?
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dd ?
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.config_pipe dd ?
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.endpoint dd ?
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.maxpacket dd ?
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.type dd ?
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.interval dd ?
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end virtual
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push ebx edi ; save used registers to be stdcall
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push eax ; save eax for checks in step 3
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; 1. Only intervals 2^k ms can be supported.
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; The core specification says that the real interval should not be greater
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; than the interval given by the endpoint descriptor, but can be less.
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; Determine the actual interval as 2^k ms.
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mov eax, ecx
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; 1a. Set [.interval] to 1 if it was zero; leave it as is otherwise
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cmp [.interval], 1
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adc [.interval], 0
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; 1b. Divide ecx by two while it is strictly greater than [.interval].
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@@:
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shr ecx, 1
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cmp [.interval], ecx
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jb @b
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; ecx = the actual interval
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;
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; For example, let ecx = 8, eax = 64.
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; The scheduler space is 32 milliseconds,
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; we need to schedule something every 8 ms;
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; there are 8 variants: schedule at times 0,8,16,24,
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; schedule at times 1,9,17,25,..., schedule at times 7,15,23,31.
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; Now concentrate: there are three nested loops,
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; * the innermost loop calculates the total periodic bandwidth scheduled
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; in the given millisecond,
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; * the intermediate loop calculates the maximum over all milliseconds
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; in the given variant, that is the quantity we're trying to minimize,
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; * the outermost loop checks all variants.
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; 2. Calculate offset between the first list and the first list for the
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; selected interval, in bytes; save in the stack for step 4.
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sub eax, ecx
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sub eax, ecx
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imul eax, sizeof.ohci_static_ep
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push eax
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imul ebx, ecx, sizeof.ohci_static_ep
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; 3. Select the best variant.
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; 3a. The outermost loop.
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; Prepare for the loop: set the current optimal bandwidth to maximum
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; possible value (so that any variant will pass the first comparison),
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; calculate delta for the intermediate loop.
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or [.bandwidth], -1
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.varloop:
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; 3b. The intermediate loop.
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; Prepare for the loop: set the maximum to be calculated to zero,
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; save counter of the outermost loop.
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xor edi, edi
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push edx
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virtual at esp
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.cur_variant dd ? ; step 3b
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.result_delta dd ? ; step 2
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.group1_limit dd ? ; function prolog
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end virtual
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.calc_max_bandwidth:
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; 3c. The innermost loop. Sum over all lists.
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xor eax, eax
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push edx
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.calc_bandwidth:
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add eax, [edx+ohci_static_ep.SoftwarePart+usb_static_ep.Bandwidth]
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mov edx, [edx+ohci_static_ep.NextList]
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test edx, edx
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jnz .calc_bandwidth
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pop edx
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; 3d. The intermediate loop continued: update maximum.
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cmp eax, edi
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jb @f
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mov edi, eax
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@@:
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; 3e. The intermediate loop continued: advance counter.
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add edx, ebx
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cmp edx, [.group1_limit]
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jb .calc_max_bandwidth
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; 3e. The intermediate loop done: restore counter of the outermost loop.
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pop edx
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; 3f. The outermost loop continued: if the current variant is
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; better (maybe not strictly) then the previous optimum, update
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; the optimal bandwidth and resulting list.
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cmp edi, [.bandwidth]
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ja @f
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mov [.bandwidth], edi
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mov [.target], edx
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@@:
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; 3g. The outermost loop continued: advance counter.
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add edx, sizeof.ohci_static_ep
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dec ecx
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jnz .varloop
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; 4. Calculate bandwidth for the new pipe.
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mov eax, [.maxpacket]
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mov cl, [.speed]
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mov ch, byte [.endpoint]
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and ch, 80h
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call calc_usb1_bandwidth
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; 5. Get the pointer to the best list.
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pop edx ; restore value from step 2
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pop ecx ; purge stack var from prolog
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add edx, [.target]
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; 6. Check that bandwidth for the new pipe plus old bandwidth
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; still fits to maximum allowed by the core specification, 90% of 12000 bits.
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mov ecx, eax
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add ecx, [.bandwidth]
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cmp ecx, 10800
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ja .no_bandwidth
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; 7. Convert {o|u}hci_static_ep to usb_static_ep, update bandwidth and return.
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add edx, ohci_static_ep.SoftwarePart
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add [edx+usb_static_ep.Bandwidth], eax
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pop edi ebx ; restore used registers to be stdcall
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ret
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.no_bandwidth:
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dbgstr 'Periodic bandwidth limit reached'
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xor edx, edx
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pop edi ebx
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ret
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endp
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; sanity check, part 2
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else
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.err select_interrupt_list must be different for UHCI and OHCI
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end if
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; Pipe is removing, update the corresponding lists.
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; We do not reorder anything, so just update book-keeping variable
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; in the list header.
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proc usb1_interrupt_list_unlink
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virtual at esp
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dd ? ; return address
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.maxpacket dd ?
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.lowspeed db ?
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.direction db ?
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rb 2
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end virtual
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; calculate bandwidth on the bus
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mov eax, [.maxpacket]
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mov ecx, dword [.lowspeed]
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call calc_usb1_bandwidth
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; find list header
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mov edx, ebx
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@@:
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mov edx, [edx+usb_pipe.NextVirt]
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cmp [edx+usb_pipe.Controller], esi
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jz @b
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; subtract pipe bandwidth
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sub [edx+usb_static_ep.Bandwidth], eax
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ret 8
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endp
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; Helper procedure for USB1 scheduler: calculate bandwidth on the bus.
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; in: low 11 bits of eax = payload size in bytes
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; in: cl = 0 - full-speed, nonzero - high-speed
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; in: ch = 0 - OUT, nonzero - IN
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; out: eax = maximal bandwidth in FS-bits
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proc calc_usb1_bandwidth
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and eax, (1 shl 11) - 1 ; get payload for one transaction
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add eax, 3 ; add 3 bytes for other fields in data packet, PID+CRC16
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test cl, cl
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jnz .low_speed
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; Multiply by 8 for bytes -> bits, by 7/6 to accomodate bit stuffing
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; and by 401/400 for IN transfers to accomodate timers difference
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; 9+107/300 for IN transfers, 9+1/3 for OUT transfers
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; For 0 <= eax < 09249355h, floor(eax * 107/300) = floor(eax * 5B4E81B5h / 2^32).
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; For 0 <= eax < 80000000h, floor(eax / 3) = floor(eax * 55555556h / 2^32).
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mov edx, 55555556h
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test ch, ch
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jz @f
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mov edx, 5B4E81B5h
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@@:
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lea ecx, [eax*9]
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mul edx
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; Add 93 extra bits: 39 bits for Token packet (8 for SYNC, 24 for token+address,
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; 4 extra bits for possible bit stuffing in token+address, 3 for EOP),
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; 18 bits for bus turn-around, 11 bits for SYNC+EOP in Data packet plus 1 bit
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; for possible timers difference, 2 bits for inter-packet delay, 20 bits for
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; Handshake packet, 2 bits for another inter-packet delay.
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lea eax, [ecx+edx+93]
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ret
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.low_speed:
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; Multiply by 8 for bytes -> bits, by 7/6 to accomodate bit stuffing,
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; by 8 for LS -> FS and by 406/50 for IN transfers to accomodate timers difference.
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; 75+59/75 for IN transfers, 74+2/3 for OUT transfers.
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mov edx, 0AAAAAABh
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test ch, ch
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mov ecx, 74
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jz @f
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mov edx, 0C962FC97h
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inc ecx
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@@:
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imul ecx, eax
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mul edx
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; Add 778 extra bits:
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; 16 bits for PRE packet, 4 bits for hub delay, 8*39 bits for Token packet
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; 8*18 bits for bus turn-around
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; (406/50)*11 bits for SYNC+EOP in Data packet,
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; 8*2 bits for inter-packet delay,
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; 16 bits for PRE packet, 4 bits for hub delay, 8*20 bits for Handshake packet,
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; 8*2 bits for another inter-packet delay.
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lea eax, [ecx+edx+778]
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ret
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endp
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; USB2 scheduler.
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; There are two parts: high-speed pipes and split-transaction pipes.
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;
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; High-speed scheduler uses the same algorithm as USB1 scheduler:
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; when adding a pipe, optimize the following quantity:
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; * for every microframe, take all bandwidth scheduled to periodic transfers,
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; * calculate maximum over all microframes,
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; * select a variant which minimizes that maximum;
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; * if there are several such variants,
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; prefer those that are closer to end of frame
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; to minimize collisions with split transactions;
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; when removing a pipe, do nothing (except for bookkeeping).
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; in: esi -> usb_controller
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; out: edx -> usb_static_ep, eax = S-Mask
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proc ehci_select_hs_interrupt_list
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; inherit some variables from usb_open_pipe
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virtual at ebp-12
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.targetsmask dd ?
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.bandwidth dd ?
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.target dd ?
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dd ?
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dd ?
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.config_pipe dd ?
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.endpoint dd ?
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.maxpacket dd ?
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.type dd ?
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.interval dd ?
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end virtual
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; prolog, initialize local vars
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or [.bandwidth], -1
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or [.target], -1
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or [.targetsmask], -1
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push ebx edi ; save used registers to be stdcall
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; 1. In EHCI, every list describes one millisecond = 8 microframes.
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; Thus, there are two significantly different branches:
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; for pipes with interval >= 8 microframes, advance to 2,
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; for pipes which should be planned in every frame (one or more microframes),
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; go to 9.
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; Note: the actual interval for high-speed devices is 2^([.interval]-1),
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; (the core specification forbids [.interval] == 0)
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mov ecx, [.interval]
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dec ecx
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cmp ecx, 3
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jb .every_frame
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; 2. Determine the actual interval in milliseconds.
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sub ecx, 3
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cmp ecx, 5 ; maximum 32ms
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jbe @f
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movi ecx, 5
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@@:
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; There are four nested loops,
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; * Loop #4 (the innermost one) calculates the total periodic bandwidth
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; scheduled in the given microframe of the given millisecond.
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; * Loop #3 calculates the maximum over all milliseconds
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; in the given variant, that is the quantity we're trying to minimize.
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; * Loops #1 and #2 check all variants;
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; loop #1 is responsible for the target millisecond,
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; loop #2 is responsible for the microframe within millisecond.
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; 3. Prepare for loops.
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; ebx = number of iterations of loop #1
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; [esp] = delta of counter for loop #3, in bytes
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; [esp+4] = delta between the first group and the target group, in bytes
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movi ebx, 1
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movi edx, sizeof.ehci_static_ep
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shl ebx, cl
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shl edx, cl
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mov eax, 64*sizeof.ehci_static_ep
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sub eax, edx
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sub eax, edx
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push eax
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push edx
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; 4. Select the best variant.
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; 4a. Loop #1: initialize counter = pointer to ehci_static_ep for
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; the target millisecond in the first group.
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lea edx, [esi+ehci_controller.IntEDs-sizeof.ehci_controller]
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.varloop0:
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; 4b. Loop #2: initialize counter = microframe within the target millisecond.
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xor ecx, ecx
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.varloop:
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; 4c. Loop #3: save counter of loop #1,
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; initialize counter with the value of loop #1 counter,
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; initialize maximal bandwidth = zero.
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xor edi, edi
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push edx
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virtual at esp
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.saved_counter1 dd ? ; step 4c
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.loop3_delta dd ? ; step 3
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.target_delta dd ? ; step 3
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end virtual
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.calc_max_bandwidth:
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; 4d. Loop #4: initialize counter with the value of loop #3 counter,
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; initialize total bandwidth = zero.
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xor eax, eax
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push edx
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.calc_bandwidth:
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; 4e. Loop #4: add the bandwidth from the current list
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; and advance to the next list, while there is one.
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add ax, [edx+ehci_static_ep.Bandwidths+ecx*2]
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mov edx, [edx+ehci_static_ep.NextList]
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test edx, edx
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jnz .calc_bandwidth
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; 4f. Loop #4 end: restore counter of loop #3.
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pop edx
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; 4g. Loop #3: update maximal bandwidth.
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cmp eax, edi
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jb @f
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mov edi, eax
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@@:
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; 4h. Loop #3: advance the counter and repeat while within the first group.
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lea eax, [esi+ehci_controller.IntEDs+32*sizeof.ehci_static_ep-sizeof.ehci_controller]
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add edx, [.loop3_delta]
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cmp edx, eax
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jb .calc_max_bandwidth
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; 4i. Loop #3 end: restore counter of loop #1.
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pop edx
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; 4j. Loop #2: if the current variant is better (maybe not strictly)
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; then the previous optimum, update the optimal bandwidth and the target.
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cmp edi, [.bandwidth]
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ja @f
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jb .update
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cmp ecx, [.targetsmask]
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jb @f
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.update:
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mov [.bandwidth], edi
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mov [.target], edx
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mov [.targetsmask], ecx
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@@:
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; 4k. Loop #2: continue 8 times for every microframe.
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inc ecx
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cmp ecx, 8
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jb .varloop
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; 4l. Loop #1: advance counter and repeat ebx times,
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; ebx was calculated in step 3.
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add edx, sizeof.ehci_static_ep
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dec ebx
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jnz .varloop0
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; 5. Calculate bandwidth for the new pipe.
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mov eax, [.maxpacket]
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call calc_hs_bandwidth
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mov ecx, [.maxpacket]
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shr ecx, 11
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inc ecx
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and ecx, 3
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imul eax, ecx
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; 6. Get the pointer to the best list.
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pop edx ; restore value from step 3
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pop edx ; get delta calculated in step 3
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add edx, [.target]
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; 7. Check that bandwidth for the new pipe plus old bandwidth
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; still fits to maximum allowed by the core specification
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; current [.bandwidth] + new bandwidth <= limit;
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; USB2 specification allows maximum 60000*80% bit times for periodic microframe
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mov ecx, [.bandwidth]
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add ecx, eax
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cmp ecx, 48000
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ja .no_bandwidth
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; 8. Convert {o|u}hci_static_ep to usb_static_ep, update bandwidth and return.
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mov ecx, [.targetsmask]
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add [edx+ehci_static_ep.Bandwidths+ecx*2], ax
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add edx, ehci_static_ep.SoftwarePart
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movi eax, 1
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shl eax, cl
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pop edi ebx ; restore used registers to be stdcall
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ret
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.no_bandwidth:
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dbgstr 'Periodic bandwidth limit reached'
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xor eax, eax
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xor edx, edx
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pop edi ebx
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ret
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.every_frame:
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; The pipe should be scheduled every frame in two or more microframes.
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; 9. Calculate maximal bandwidth for every microframe: three nested loops.
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; 9a. The outermost loop: ebx = microframe to calculate.
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xor ebx, ebx
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.calc_all_bandwidths:
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; 9b. The intermediate loop:
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; edx = pointer to ehci_static_ep in the first group, [esp] = counter,
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; edi = maximal bandwidth
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lea edx, [esi+ehci_controller.IntEDs-sizeof.ehci_controller]
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xor edi, edi
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push 32
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.calc_max_bandwidth2:
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; 9c. The innermost loop: calculate bandwidth for the given microframe
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; in the given frame.
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xor eax, eax
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push edx
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.calc_bandwidth2:
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add ax, [edx+ehci_static_ep.Bandwidths+ebx*2]
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mov edx, [edx+ehci_static_ep.NextList]
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test edx, edx
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jnz .calc_bandwidth2
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pop edx
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; 9d. The intermediate loop continued: update maximal bandwidth.
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cmp eax, edi
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jb @f
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mov edi, eax
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@@:
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add edx, sizeof.ehci_static_ep
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dec dword [esp]
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jnz .calc_max_bandwidth2
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pop eax
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; 9e. Push the calculated maximal bandwidth and continue the outermost loop.
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push edi
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inc ebx
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cmp ebx, 8
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jb .calc_all_bandwidths
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virtual at esp
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.bandwidth7 dd ?
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.bandwidth6 dd ?
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.bandwidth5 dd ?
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.bandwidth4 dd ?
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.bandwidth3 dd ?
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.bandwidth2 dd ?
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.bandwidth1 dd ?
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.bandwidth0 dd ?
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end virtual
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; 10. Select the best variant.
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; edx = S-Mask = bitmask of scheduled microframes
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movi edx, 0x11
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cmp ecx, 1
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ja @f
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mov dl, 0x55
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jz @f
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mov dl, 0xFF
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@@:
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; try all variants edx, edx shl 1, edx shl 2, ...
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; while they fit in the lower byte (8 microframes per frame)
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.select_best_mframe:
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xor edi, edi
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mov ecx, edx
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mov eax, esp
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.calc_mframe:
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add cl, cl
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jnc @f
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cmp edi, [eax]
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jae @f
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mov edi, [eax]
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@@:
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add eax, 4
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test cl, cl
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jnz .calc_mframe
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cmp [.bandwidth], edi
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jb @f
|
|
mov [.bandwidth], edi
|
|
mov [.targetsmask], edx
|
|
@@:
|
|
add dl, dl
|
|
jnc .select_best_mframe
|
|
; 11. Restore stack after step 9.
|
|
add esp, 8*4
|
|
; 12. Get the pointer to the target list (responsible for every microframe).
|
|
lea edx, [esi+ehci_controller.IntEDs.SoftwarePart+62*sizeof.ehci_static_ep-sizeof.ehci_controller]
|
|
; 13. Calculate bandwidth on the bus.
|
|
mov eax, [.maxpacket]
|
|
call calc_hs_bandwidth
|
|
mov ecx, [.maxpacket]
|
|
shr ecx, 11
|
|
inc ecx
|
|
and ecx, 3
|
|
imul eax, ecx
|
|
; 14. Check that current [.bandwidth] + new bandwidth <= limit;
|
|
; USB2 specification allows maximum 60000*80% bit times for periodic microframe.
|
|
mov ecx, [.bandwidth]
|
|
add ecx, eax
|
|
cmp ecx, 48000
|
|
ja .no_bandwidth
|
|
; 15. Update bandwidths including the new pipe.
|
|
mov ecx, [.targetsmask]
|
|
lea edi, [edx+ehci_static_ep.Bandwidths-ehci_static_ep.SoftwarePart]
|
|
.update_bandwidths:
|
|
shr ecx, 1
|
|
jnc @f
|
|
add [edi], ax
|
|
@@:
|
|
add edi, 2
|
|
test ecx, ecx
|
|
jnz .update_bandwidths
|
|
; 16. Return target list and target S-Mask.
|
|
mov eax, [.targetsmask]
|
|
pop edi ebx ; restore used registers to be stdcall
|
|
ret
|
|
endp
|
|
|
|
; Pipe is removing, update the corresponding lists.
|
|
; We do not reorder anything, so just update book-keeping variable
|
|
; in the list header.
|
|
proc ehci_hs_interrupt_list_unlink
|
|
movzx eax, word [ebx+ehci_pipe.Token-sizeof.ehci_pipe+2]
|
|
; calculate bandwidth
|
|
call calc_hs_bandwidth
|
|
mov ecx, [ebx+ehci_pipe.Flags-sizeof.ehci_pipe]
|
|
shr ecx, 30
|
|
imul eax, ecx
|
|
movzx ecx, byte [ebx+ehci_pipe.Flags-sizeof.ehci_pipe]
|
|
; get target list
|
|
mov edx, [ebx+ehci_pipe.BaseList-sizeof.ehci_pipe]
|
|
; update bandwidth
|
|
.dec_bandwidth:
|
|
shr ecx, 1
|
|
jnc @f
|
|
sub word [edx+ehci_static_ep.Bandwidths - ehci_static_ep.SoftwarePart], ax
|
|
@@:
|
|
add edx, 2
|
|
test ecx, ecx
|
|
jnz .dec_bandwidth
|
|
; return
|
|
ret
|
|
endp
|
|
|
|
; Helper procedure for USB2 scheduler: calculate bandwidth on the bus.
|
|
; in: low 11 bits of eax = payload size in bytes
|
|
; out: eax = maximal bandwidth in HS-bits
|
|
proc calc_hs_bandwidth
|
|
and eax, (1 shl 11) - 1 ; get payload for one transaction
|
|
add eax, 3 ; add 3 bytes for other fields in data packet, PID+CRC16
|
|
; Multiply by 8 for bytes -> bits and then by 7/6 to accomodate bit stuffing;
|
|
; total 28/3 = 9+1/3
|
|
mov edx, 55555556h
|
|
lea ecx, [eax*9]
|
|
mul edx
|
|
; Add 989 extra bits: 68 bits for Token packet (32 for SYNC, 24 for token+address,
|
|
; 4 extra bits for possible bit stuffing in token+address, 8 for EOP),
|
|
; 736 bits for bus turn-around, 40 bits for SYNC+EOP in Data packet,
|
|
; 8 bits for inter-packet delay, 49 bits for Handshake packet,
|
|
; 88 bits for another inter-packet delay.
|
|
lea eax, [ecx+edx+989]
|
|
ret
|
|
endp
|
|
|
|
; Split-transaction scheduler (aka TT scheduler, TT stands for Transaction
|
|
; Translator, section 11.14 of the core spec) needs to schedule three event
|
|
; types on two buses: Start-Split and Complete-Split on HS bus and normal
|
|
; transaction on FS/LS bus.
|
|
; Assume that FS/LS bus is more restricted and more important to be scheduled
|
|
; uniformly, so select the variant which minimizes maximal used bandwidth
|
|
; on FS/LS bus and does not overflow HS bus.
|
|
; If there are several such variants, prefer variants which is closest to
|
|
; start of frame, and within the same microframe consider HS bandwidth
|
|
; utilization as a last criteria.
|
|
|
|
; The procedure ehci_select_tt_interrupt_list has been splitted into several
|
|
; macro, each representing a logical step of the procedure,
|
|
; to simplify understanding what is going on. Consider all the following macro
|
|
; as logical parts of one procedure, they are meaningless outside the context.
|
|
|
|
; Given a frame, calculate bandwidth occupied by already opened pipes
|
|
; in every microframe.
|
|
; Look for both HS and FS/LS buses: there are 16 words of information,
|
|
; 8 for HS bus, 8 for FS/LS bus, for every microframe.
|
|
; Since we count already opened pipes, the total bandwidth in every microframe
|
|
; is less than 60000 bits (and even 60000*80% bits), otherwise the scheduler
|
|
; would not allow to open those pipes.
|
|
; edi -> first list for the frame
|
|
macro tt_calc_bandwidth_in_frame
|
|
{
|
|
local .lists, .pipes, .pipes_done, .carry
|
|
; 1. Zero everything.
|
|
xor eax, eax
|
|
mov edx, edi
|
|
repeat 4
|
|
mov dword [.budget+(%-1)*4], eax
|
|
end repeat
|
|
repeat 4
|
|
mov dword [.hs_bandwidth+(%-1)*4], eax
|
|
end repeat
|
|
mov [.total_budget], ax
|
|
; Loop over all lists for the given frame.
|
|
.lists:
|
|
; 2. Total HS bandwidth for all pipes in one list is kept inside list header,
|
|
; add it. Note that overflow is impossible, so we may add entire dwords.
|
|
mov ebx, [edx+ehci_static_ep.SoftwarePart+usb_static_ep.NextVirt]
|
|
repeat 4
|
|
mov eax, dword [edx+ehci_static_ep.Bandwidths+(%-1)*4]
|
|
add dword [.hs_bandwidth+(%-1)*4], eax
|
|
end repeat
|
|
; Loop over all pipes in the given list.
|
|
add edx, ehci_static_ep.SoftwarePart
|
|
.pipes:
|
|
cmp ebx, edx
|
|
jz .pipes_done
|
|
; 3. For every pipe in every list for the given frame:
|
|
; 3a. Check whether the pipe resides on the same FS/LS bus as the new pipe.
|
|
; If not, skip this pipe.
|
|
mov eax, [ebx+usb_pipe.DeviceData]
|
|
mov eax, [eax+usb_device_data.TTHub]
|
|
cmp eax, [.tthub]
|
|
jnz @f
|
|
; 3b. Calculate FS/LS budget for the opened pipe.
|
|
; Note that eax = TTHub after 3a.
|
|
call tt_calc_budget
|
|
; 3c. Update total budget: add the value from 3b
|
|
; to the budget of the first microframe scheduled for this pipe.
|
|
bsf ecx, [ebx+ehci_pipe.Flags-sizeof.ehci_pipe]
|
|
add [.budget+ecx*2], ax
|
|
@@:
|
|
mov ebx, [ebx+usb_pipe.NextVirt]
|
|
jmp .pipes
|
|
.pipes_done:
|
|
mov edx, [edx+ehci_static_ep.NextList-ehci_static_ep.SoftwarePart]
|
|
test edx, edx
|
|
jnz .lists
|
|
; 4. If the budget for some microframe is exceeded, carry it to the following
|
|
; microframe(s). The actual size of one microframe is 187.5 raw bytes;
|
|
; the core spec says that 188 bytes should be scheduled in every microframe.
|
|
xor eax, eax
|
|
xor ecx, ecx
|
|
.carry:
|
|
xor edx, edx
|
|
add ax, [.budget+ecx*2]
|
|
cmp ax, 188
|
|
jbe @f
|
|
mov dx, ax
|
|
mov ax, 188
|
|
sub dx, ax
|
|
@@:
|
|
mov [.budget+ecx*2], ax
|
|
add [.total_budget], ax
|
|
mov ax, dx
|
|
inc ecx
|
|
cmp ecx, 8
|
|
jb .carry
|
|
}
|
|
|
|
; Checks whether the new pipe fits in the existing FS budget
|
|
; starting from the given microframe. If not, mark the microframe
|
|
; as impossible for scheduling.
|
|
; in: ecx = microframe
|
|
macro tt_exclude_microframe_if_no_budget
|
|
{
|
|
local .loop, .good, .bad
|
|
; 1. If the new budget plus the current budget does not exceed 188 bytes,
|
|
; the variant is possible.
|
|
mov ax, [.budget+ecx*2]
|
|
mov edx, ecx
|
|
add ax, [.new_budget]
|
|
sub ax, 188
|
|
jbe .good
|
|
; 2. Otherwise,
|
|
; a) nothing should be scheduled in some following microframes,
|
|
; b) after adding the new budget everything should fit in first 6 microframes,
|
|
; this guarantees that even in the worst case 90% limit is satisfied.
|
|
.loop:
|
|
cmp edx, 5
|
|
jae .bad
|
|
cmp [.budget+(edx+1)*2], 0
|
|
jnz .bad
|
|
inc edx
|
|
sub ax, 188
|
|
ja .loop
|
|
.bad:
|
|
btr [.possible_microframes], ecx
|
|
.good:
|
|
}
|
|
|
|
; Calculate data corresponding to the particular scheduling variant for the new pipe.
|
|
; Data describe the current scheduling state collected over all frames touched
|
|
; by the given variant: maximal HS bandwidth, maximal FS/LS budget,
|
|
; which microframes fit in the current FS/LS budget for all frames.
|
|
macro tt_calc_statistics_for_one_variant
|
|
{
|
|
local .frames, .microframes
|
|
; 1. Initialize: zero maximal bandwidth,
|
|
; first 6 microframes are possible for scheduling.
|
|
xor eax, eax
|
|
repeat 4
|
|
mov dword [.max_hs_bandwidth+(%-1)*4], eax
|
|
end repeat
|
|
mov [.max_fs_bandwidth], ax
|
|
mov [.possible_microframes], 0x3F
|
|
; Loop over all frames starting with [.variant] advancing by [.variant_delta].
|
|
mov edi, [.variant]
|
|
.frames:
|
|
; 2. Calculate statistics for one frame.
|
|
tt_calc_bandwidth_in_frame
|
|
; 3. Update maximal FS budget.
|
|
mov ax, [.total_budget]
|
|
cmp ax, [.max_fs_bandwidth]
|
|
jb @f
|
|
mov [.max_fs_bandwidth], ax
|
|
@@:
|
|
; 4. For every microframe, update maximal HS bandwidth
|
|
; and check whether the microframe is allowed for scheduling.
|
|
xor ecx, ecx
|
|
.microframes:
|
|
mov ax, [.hs_bandwidth+ecx*2]
|
|
cmp ax, [.max_hs_bandwidth+ecx*2]
|
|
jb @f
|
|
mov [.max_hs_bandwidth+ecx*2], ax
|
|
@@:
|
|
tt_exclude_microframe_if_no_budget
|
|
inc ecx
|
|
cmp ecx, 8
|
|
jb .microframes
|
|
; Stop loop when outside of first descriptor group.
|
|
lea eax, [esi+ehci_controller.IntEDs+32*sizeof.ehci_static_ep-sizeof.ehci_controller]
|
|
add edi, [.variant_delta]
|
|
cmp edi, eax
|
|
jb .frames
|
|
}
|
|
|
|
struct usb_split_info
|
|
microframe_mask dd ? ; lower byte is S-mask, second byte is C-mask
|
|
ssplit_bandwidth dd ?
|
|
csplit_bandwidth dd ?
|
|
ends
|
|
|
|
; Check whether the current variant and the current microframe are allowed
|
|
; for scheduling. If so, check whether they are better than the previously
|
|
; selected variant+microframe, if any. If so, update the previously selected
|
|
; variant+microframe to current ones.
|
|
; ecx = microframe, [.variant] = variant
|
|
macro tt_check_variant_microframe
|
|
{
|
|
local .nothing, .update, .ssplit, .csplit, .csplit_done
|
|
; 1. If the current microframe does not fit in existing FS budget, do nothing.
|
|
bt [.possible_microframes], ecx
|
|
jnc .nothing
|
|
; 2. Calculate maximal HS bandwidth over all affected microframes.
|
|
; 2a. Start-split phase: one or more microframes starting with ecx,
|
|
; coded in lower byte of .info.microframe_mask.
|
|
xor ebx, ebx
|
|
xor edx, edx
|
|
.ssplit:
|
|
lea eax, [ecx+edx]
|
|
movzx eax, [.max_hs_bandwidth+eax*2]
|
|
add eax, [.info.ssplit_bandwidth]
|
|
cmp ebx, eax
|
|
ja @f
|
|
mov ebx, eax
|
|
@@:
|
|
inc edx
|
|
bt [.info.microframe_mask], edx
|
|
jc .ssplit
|
|
; 2b. Complete-split phase: zero or more microframes starting with
|
|
; ecx+(last start-split microframe)+2,
|
|
; coded in second byte of .info.microframe_mask.
|
|
add edx, 8
|
|
.csplit:
|
|
inc edx
|
|
bt [.info.microframe_mask], edx
|
|
jnc .csplit_done
|
|
lea eax, [ecx+edx]
|
|
cmp eax, 8
|
|
jae .csplit_done
|
|
movzx eax, [.max_hs_bandwidth+(eax-8)*2]
|
|
add eax, [.info.csplit_bandwidth]
|
|
cmp ebx, eax
|
|
ja .csplit
|
|
mov ebx, eax
|
|
jmp .csplit
|
|
.csplit_done:
|
|
; 3. Check that current HS bandwidth + new bandwidth <= limit;
|
|
; USB2 specification allows maximum 60000*80% bit times for periodic microframe.
|
|
cmp ebx, 48000
|
|
ja .nothing
|
|
; 4. This variant is possible for scheduling.
|
|
; Check whether it is better than the currently selected one.
|
|
; 4a. The primary criteria: FS/LS bandwidth.
|
|
mov ax, [.max_fs_bandwidth]
|
|
cmp ax, [.best_fs_bandwidth]
|
|
ja .nothing
|
|
jb .update
|
|
; 4b. The secondary criteria: prefer microframes which are closer to start of frame.
|
|
cmp ecx, [.targetsmask]
|
|
ja .nothing
|
|
jb .update
|
|
; 4c. The last criteria: HS bandwidth.
|
|
cmp ebx, [.bandwidth]
|
|
ja .nothing
|
|
.update:
|
|
; 5. This variant is better than the previously selected.
|
|
; Update the best variant with current data.
|
|
mov [.best_fs_bandwidth], ax
|
|
mov [.bandwidth], ebx
|
|
mov [.targetsmask], ecx
|
|
mov eax, [.variant]
|
|
mov [.target], eax
|
|
.nothing:
|
|
}
|
|
|
|
; TT scheduler: add new pipe.
|
|
; in: esi -> usb_controller, edi -> usb_pipe
|
|
; out: edx -> usb_static_ep, eax = S-Mask
|
|
proc ehci_select_tt_interrupt_list
|
|
virtual at ebp-12-.local_vars_size
|
|
.local_vars_start:
|
|
.info usb_split_info
|
|
.new_budget dw ?
|
|
.total_budget dw ?
|
|
.possible_microframes dd ?
|
|
.tthub dd ?
|
|
.budget rw 8
|
|
.hs_bandwidth rw 8
|
|
.max_hs_bandwidth rw 8
|
|
.max_fs_bandwidth dw ?
|
|
.best_fs_bandwidth dw ?
|
|
.variant dd ?
|
|
.variant_delta dd ?
|
|
.target_delta dd ?
|
|
.local_vars_size = $ - .local_vars_start
|
|
|
|
.targetsmask dd ?
|
|
.bandwidth dd ?
|
|
.target dd ?
|
|
dd ?
|
|
dd ?
|
|
.config_pipe dd ?
|
|
.endpoint dd ?
|
|
.maxpacket dd ?
|
|
.type dd ?
|
|
.interval dd ?
|
|
end virtual
|
|
mov eax, [edi+ehci_pipe.Token-sizeof.ehci_pipe]
|
|
shr eax, 16
|
|
and eax, (1 shl 11) - 1
|
|
push ebx edi
|
|
; 1. Compute the real interval. FS/LS devices encode the interval as
|
|
; number of milliseconds. Use the maximal power of two that is not greater than
|
|
; the given interval and EHCI scheduling area = 32 frames.
|
|
cmp [.interval], 1
|
|
adc [.interval], 0
|
|
mov ecx, 64
|
|
mov eax, 64 * sizeof.ehci_static_ep
|
|
@@:
|
|
shr ecx, 1
|
|
cmp [.interval], ecx
|
|
jb @b
|
|
mov [.interval], ecx
|
|
; 2. Compute variables for further calculations.
|
|
; 2a. [.variant_delta] is delta between two lists from the first group
|
|
; that correspond to the same variant.
|
|
imul ecx, sizeof.ehci_static_ep
|
|
mov [.variant_delta], ecx
|
|
; 2b. [.target_delta] is delta between the final answer from the group
|
|
; corresponding to [.interval] and the item from the first group.
|
|
sub eax, ecx
|
|
sub eax, ecx
|
|
mov [.target_delta], eax
|
|
; 2c. [.variant] is the first list from the first group that corresponds
|
|
; to the current variant.
|
|
lea eax, [esi+ehci_controller.IntEDs-sizeof.ehci_controller]
|
|
mov [.variant], eax
|
|
; 2d. [.tthub] identifies TT hub for new pipe, [.new_budget] is FS budget
|
|
; for new pipe.
|
|
mov eax, [edi+usb_pipe.DeviceData]
|
|
mov eax, [eax+usb_device_data.TTHub]
|
|
mov ebx, edi
|
|
mov [.tthub], eax
|
|
call tt_calc_budget
|
|
mov [.new_budget], ax
|
|
; 2e. [.usb_split_info] describes bandwidth used by new pipe on HS bus.
|
|
lea edi, [.info]
|
|
call tt_fill_split_info
|
|
test eax, eax
|
|
jz .no_bandwidth
|
|
; 2f. There is no best variant yet, put maximal possible values,
|
|
; so any variant would be better than the "current".
|
|
or [.best_fs_bandwidth], -1
|
|
or [.target], -1
|
|
or [.bandwidth], -1
|
|
or [.targetsmask], -1
|
|
; 3. Loop over all variants, for every variant decide whether it is acceptable,
|
|
; select the best variant from all acceptable variants.
|
|
.check_variants:
|
|
tt_calc_statistics_for_one_variant
|
|
xor ecx, ecx
|
|
.check_microframes:
|
|
tt_check_variant_microframe
|
|
inc ecx
|
|
cmp ecx, 6
|
|
jb .check_microframes
|
|
add [.variant], sizeof.ehci_static_ep
|
|
dec [.interval]
|
|
jnz .check_variants
|
|
; 4. If there is no acceptable variants, return error.
|
|
mov ecx, [.targetsmask]
|
|
mov edx, [.target]
|
|
cmp ecx, -1
|
|
jz .no_bandwidth
|
|
; 5. Calculate the answer: edx -> selected list, eax = S-Mask and C-Mask.
|
|
mov eax, [.info.microframe_mask]
|
|
add edx, [.target_delta]
|
|
shl eax, cl
|
|
and eax, 0xFFFF
|
|
; 6. Update HS bandwidths in the selected list.
|
|
xor ecx, ecx
|
|
mov ebx, [.info.ssplit_bandwidth]
|
|
.update_ssplit:
|
|
bt eax, ecx
|
|
jnc @f
|
|
add [edx+ehci_static_ep.Bandwidths+ecx*2], bx
|
|
@@:
|
|
inc ecx
|
|
cmp ecx, 8
|
|
jb .update_ssplit
|
|
mov ebx, [.info.csplit_bandwidth]
|
|
.update_csplit:
|
|
bt eax, ecx
|
|
jnc @f
|
|
add [edx+ehci_static_ep.Bandwidths+(ecx-8)*2], bx
|
|
@@:
|
|
inc ecx
|
|
cmp ecx, 16
|
|
jb .update_csplit
|
|
; 7. Return.
|
|
add edx, ehci_static_ep.SoftwarePart
|
|
pop edi ebx
|
|
ret
|
|
.no_bandwidth:
|
|
dbgstr 'Periodic bandwidth limit reached'
|
|
xor eax, eax
|
|
xor edx, edx
|
|
pop edi ebx
|
|
ret
|
|
endp
|
|
|
|
; Pipe is removing, update the corresponding lists.
|
|
; We do not reorder anything, so just update book-keeping variable
|
|
; in the list header.
|
|
proc ehci_fs_interrupt_list_unlink
|
|
; calculate bandwidth
|
|
push edi
|
|
sub esp, sizeof.usb_split_info
|
|
mov edi, esp
|
|
call tt_fill_split_info
|
|
; get target list
|
|
mov edx, [ebx+ehci_pipe.BaseList-sizeof.ehci_pipe]
|
|
; update bandwidth for Start-Split
|
|
mov eax, [edi+usb_split_info.ssplit_bandwidth]
|
|
xor ecx, ecx
|
|
.dec_bandwidth_1:
|
|
bt [ebx+ehci_pipe.Flags-sizeof.ehci_pipe], ecx
|
|
jnc @f
|
|
sub word [edx+ecx*2+ehci_static_ep.Bandwidths - ehci_static_ep.SoftwarePart], ax
|
|
@@:
|
|
inc ecx
|
|
cmp ecx, 8
|
|
jb .dec_bandwidth_1
|
|
; update bandwidth for Complete-Split
|
|
mov eax, [edi+usb_split_info.csplit_bandwidth]
|
|
.dec_bandwidth_2:
|
|
bt [ebx+ehci_pipe.Flags-sizeof.ehci_pipe], ecx
|
|
jnc @f
|
|
sub word [edx+(ecx-8)*2+ehci_static_ep.Bandwidths - ehci_static_ep.SoftwarePart], ax
|
|
@@:
|
|
inc ecx
|
|
cmp ecx, 16
|
|
jb .dec_bandwidth_2
|
|
add esp, sizeof.usb_split_info
|
|
pop edi
|
|
ret
|
|
endp
|
|
|
|
; Helper procedure for ehci_select_tt_interrupt_list.
|
|
; Calculates "best-case budget" according to the core spec,
|
|
; that is, number of bytes (not bits) corresponding to "optimistic" transaction
|
|
; time, including inter-packet delays/bus turn-around time,
|
|
; but without bit stuffing and timers drift.
|
|
; One extra TT-specific delay is added: TT think time from the hub descriptor.
|
|
; Similar to calc_usb1_bandwidth with corresponding changes.
|
|
; eax -> usb_hub with TT, ebx -> usb_pipe
|
|
proc tt_calc_budget
|
|
movzx ecx, [eax+usb_hub.HubCharacteristics]
|
|
shr ecx, 5
|
|
and ecx, 3 ; 1+ecx = TT think time in FS-bytes
|
|
mov eax, [ebx+ehci_pipe.Token-sizeof.ehci_pipe]
|
|
shr eax, 16
|
|
and eax, (1 shl 11) - 1 ; get data length
|
|
bt [ebx+ehci_pipe.Token-sizeof.ehci_pipe], 12
|
|
jc .low_speed
|
|
; Full-speed interrupt IN/OUT:
|
|
; 33 bits for Token packet (8 for SYNC, 24 for token+address, 3 for EOP),
|
|
; 18 bits for bus turn-around, 11 bits for SYNC+EOP in Data packet,
|
|
; 2 bits for inter-packet delay, 19 bits for Handshake packet,
|
|
; 2 bits for another inter-packet delay. 85 bits total, pad to 11 bytes.
|
|
lea eax, [eax+11+ecx+1]
|
|
; 1 byte is minimal TT think time in addition to ecx.
|
|
ret
|
|
.low_speed:
|
|
; Low-speed interrupt IN/OUT:
|
|
; multiply by 8 for LS -> FS,
|
|
; add 85 bytes as in full-speed interrupt and extra 5 bytes for two PRE packets
|
|
; and two hub delays.
|
|
; 1 byte is minimal TT think time in addition to ecx.
|
|
lea eax, [eax*8+90+ecx+1]
|
|
ret
|
|
endp
|
|
|
|
; Helper procedure for TT scheduler.
|
|
; Calculates Start-Split/Complete-Split masks and HS bandwidths.
|
|
; ebx -> usb_pipe, edi -> usb_split_info
|
|
proc tt_fill_split_info
|
|
; Interrupt endpoints.
|
|
; The core spec says in 5.7.3 "Interrupt Transfer Packet Size Constraints" that:
|
|
; The maximum allowable interrupt data payload size is 64 bytes or less for full-speed.
|
|
; Low-speed devices are limited to eight bytes or less maximum data payload size.
|
|
; This is important for scheduling, it guarantees that in any case transaction fits
|
|
; in two microframes (usually one, two if transaction has started too late in the first
|
|
; microframe), so check it.
|
|
mov eax, [ebx+ehci_pipe.Token-sizeof.ehci_pipe]
|
|
mov ecx, 8
|
|
bt eax, 12
|
|
jc @f
|
|
mov ecx, 64
|
|
@@:
|
|
shr eax, 16
|
|
and eax, (1 shl 11) - 1 ; get data length
|
|
cmp eax, ecx
|
|
ja .error
|
|
add eax, 3 ; add 3 bytes for other fields in data packet, PID+CRC16
|
|
; Multiply by 8 for bytes -> bits and then by 7/6 to accomodate bit stuffing;
|
|
; total 28/3 = 9+1/3
|
|
mov edx, 55555556h
|
|
lea ecx, [eax*9]
|
|
mul edx
|
|
; One start-split, three complete-splits (unless the last is too far,
|
|
; but this is handled by the caller).
|
|
mov eax, [ebx+usb_pipe.LastTD]
|
|
mov [edi+usb_split_info.microframe_mask], 0x1C01
|
|
; Structure and HS bandwidth of packets depends on the direction.
|
|
bt [eax+ehci_gtd.Token-sizeof.ehci_gtd], 8
|
|
jc .interrupt_in
|
|
.interrupt_out:
|
|
; Start-Split phase:
|
|
; 77 bits for SPLIT packet (32 for SYNC, 8 for EOP, 32 for data, 5 for bit stuffing),
|
|
; 88 bits for inter-packet delay, 68 bits for Token packet,
|
|
; 88 bits for inter-packet delay, 40 bits for SYNC+EOP in Data packet,
|
|
; 88 bits for last inter-packet delay, total 449 bits.
|
|
lea eax, [edx+ecx+449]
|
|
mov [edi+usb_split_info.ssplit_bandwidth], eax
|
|
; Complete-Split phase:
|
|
; 77 bits for SPLIT packet,
|
|
; 88 bits for inter-packet delay, 68 bits for Token packet,
|
|
; 736 bits for bus turn-around, 49 bits for Handshake packet,
|
|
; 8 bits for inter-packet delay, total 1026 bits.
|
|
mov [edi+usb_split_info.csplit_bandwidth], 1026
|
|
ret
|
|
.interrupt_in:
|
|
; Start-Split phase:
|
|
; 77 bits for SPLIT packet, 88 bits for inter-packet delay,
|
|
; 68 bits for Token packet, 88 bits for another inter-packet delay,
|
|
; total 321 bits.
|
|
mov [edi+usb_split_info.ssplit_bandwidth], 321
|
|
; Complete-Split phase:
|
|
; 77 bits for SPLIT packet, 88 bits for inter-packet delay,
|
|
; 68 bits for Token packet, 736 bits for bus turn-around,
|
|
; 40 bits for SYNC+EOP in Data packet, 8 bits for inter-packet delay,
|
|
; total 1017 bits.
|
|
lea eax, [edx+ecx+1017]
|
|
mov [edi+usb_split_info.csplit_bandwidth], eax
|
|
ret
|
|
.error:
|
|
xor eax, eax
|
|
ret
|
|
endp
|