usbdrv/usbdrvasm.S@9e9b2c78bd31
usbdrv/usbdrvasm.S
Thu, 16 Feb 2017 14:40:23 +0100
- author
- Malte Di Donato <mdd@neo-soft.org>
- date
- Thu, 16 Feb 2017 14:40:23 +0100
- changeset 0
- 9e9b2c78bd31
- permissions
- -rw-r--r--
added V-USB stack
/* Name: usbdrvasm.S * Project: V-USB, virtual USB port for Atmel's(r) AVR(r) microcontrollers * Author: Christian Starkjohann * Creation Date: 2007-06-13 * Tabsize: 4 * Copyright: (c) 2007 by OBJECTIVE DEVELOPMENT Software GmbH * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt) */ /* General Description: This module is the assembler part of the USB driver. This file contains general code (preprocessor acrobatics and CRC computation) and then includes the file appropriate for the given clock rate. */ #define __SFR_OFFSET 0 /* used by avr-libc's register definitions */ #include "usbportability.h" #include "usbdrv.h" /* for common defs */ /* register names */ #define x1 r16 #define x2 r17 #define shift r18 #define cnt r19 #define x3 r20 #define x4 r21 #define x5 r22 #define bitcnt x5 #define phase x4 #define leap x4 /* Some assembler dependent definitions and declarations: */ #ifdef __IAR_SYSTEMS_ASM__ extern usbRxBuf, usbDeviceAddr, usbNewDeviceAddr, usbInputBufOffset extern usbCurrentTok, usbRxLen, usbRxToken, usbTxLen extern usbTxBuf, usbTxStatus1, usbTxStatus3 # if USB_COUNT_SOF extern usbSofCount # endif public usbCrc16 public usbCrc16Append COMMON INTVEC # ifndef USB_INTR_VECTOR ORG INT0_vect # else /* USB_INTR_VECTOR */ ORG USB_INTR_VECTOR # undef USB_INTR_VECTOR # endif /* USB_INTR_VECTOR */ # define USB_INTR_VECTOR usbInterruptHandler rjmp USB_INTR_VECTOR RSEG CODE #else /* __IAR_SYSTEMS_ASM__ */ # ifndef USB_INTR_VECTOR /* default to hardware interrupt INT0 */ # ifdef INT0_vect # define USB_INTR_VECTOR INT0_vect // this is the "new" define for the vector # else # define USB_INTR_VECTOR SIG_INTERRUPT0 // this is the "old" vector # endif # endif .text .global USB_INTR_VECTOR .type USB_INTR_VECTOR, @function .global usbCrc16 .global usbCrc16Append #endif /* __IAR_SYSTEMS_ASM__ */ #if USB_INTR_PENDING < 0x40 /* This is an I/O address, use in and out */ # define USB_LOAD_PENDING(reg) in reg, USB_INTR_PENDING # define USB_STORE_PENDING(reg) out USB_INTR_PENDING, reg #else /* It's a memory address, use lds and sts */ # define USB_LOAD_PENDING(reg) lds reg, USB_INTR_PENDING # define USB_STORE_PENDING(reg) sts USB_INTR_PENDING, reg #endif #define usbTxLen1 usbTxStatus1 #define usbTxBuf1 (usbTxStatus1 + 1) #define usbTxLen3 usbTxStatus3 #define usbTxBuf3 (usbTxStatus3 + 1) ;---------------------------------------------------------------------------- ; Utility functions ;---------------------------------------------------------------------------- #ifdef __IAR_SYSTEMS_ASM__ /* Register assignments for usbCrc16 on IAR cc */ /* Calling conventions on IAR: * First parameter passed in r16/r17, second in r18/r19 and so on. * Callee must preserve r4-r15, r24-r29 (r28/r29 is frame pointer) * Result is passed in r16/r17 * In case of the "tiny" memory model, pointers are only 8 bit with no * padding. We therefore pass argument 1 as "16 bit unsigned". */ RTMODEL "__rt_version", "3" /* The line above will generate an error if cc calling conventions change. * The value "3" above is valid for IAR 4.10B/W32 */ # define argLen r18 /* argument 2 */ # define argPtrL r16 /* argument 1 */ # define argPtrH r17 /* argument 1 */ # define resCrcL r16 /* result */ # define resCrcH r17 /* result */ # define ptrL ZL # define ptrH ZH # define ptr Z # define byte r22 # define bitCnt r19 # define polyL r20 # define polyH r21 # define scratch r23 #else /* __IAR_SYSTEMS_ASM__ */ /* Register assignments for usbCrc16 on gcc */ /* Calling conventions on gcc: * First parameter passed in r24/r25, second in r22/23 and so on. * Callee must preserve r1-r17, r28/r29 * Result is passed in r24/r25 */ # define argLen r22 /* argument 2 */ # define argPtrL r24 /* argument 1 */ # define argPtrH r25 /* argument 1 */ # define resCrcL r24 /* result */ # define resCrcH r25 /* result */ # define ptrL XL # define ptrH XH # define ptr x # define byte r18 # define bitCnt r19 # define polyL r20 # define polyH r21 # define scratch r23 #endif #if USB_USE_FAST_CRC ; This implementation is faster, but has bigger code size ; Thanks to Slawomir Fras (BoskiDialer) for this code! ; It implements the following C pseudo-code: ; unsigned table(unsigned char x) ; { ; unsigned value; ; ; value = (unsigned)x << 6; ; value ^= (unsigned)x << 7; ; if(parity(x)) ; value ^= 0xc001; ; return value; ; } ; unsigned usbCrc16(unsigned char *argPtr, unsigned char argLen) ; { ; unsigned crc = 0xffff; ; ; while(argLen--) ; crc = table(lo8(crc) ^ *argPtr++) ^ hi8(crc); ; return ~crc; ; } ; extern unsigned usbCrc16(unsigned char *argPtr, unsigned char argLen); ; argPtr r24+25 / r16+r17 ; argLen r22 / r18 ; temp variables: ; byte r18 / r22 ; scratch r23 ; resCrc r24+r25 / r16+r17 ; ptr X / Z usbCrc16: mov ptrL, argPtrL mov ptrH, argPtrH ldi resCrcL, 0xFF ldi resCrcH, 0xFF rjmp usbCrc16LoopTest usbCrc16ByteLoop: ld byte, ptr+ eor resCrcL, byte ; resCrcL is now 'x' in table() mov byte, resCrcL ; compute parity of 'x' swap byte eor byte, resCrcL mov scratch, byte lsr byte lsr byte eor byte, scratch inc byte lsr byte andi byte, 1 ; byte is now parity(x) mov scratch, resCrcL mov resCrcL, resCrcH eor resCrcL, byte ; low byte of if(parity(x)) value ^= 0xc001; neg byte andi byte, 0xc0 mov resCrcH, byte ; high byte of if(parity(x)) value ^= 0xc001; clr byte lsr scratch ror byte eor resCrcH, scratch eor resCrcL, byte lsr scratch ror byte eor resCrcH, scratch eor resCrcL, byte usbCrc16LoopTest: subi argLen, 1 brsh usbCrc16ByteLoop com resCrcL com resCrcH ret #else /* USB_USE_FAST_CRC */ ; This implementation is slower, but has less code size ; ; extern unsigned usbCrc16(unsigned char *argPtr, unsigned char argLen); ; argPtr r24+25 / r16+r17 ; argLen r22 / r18 ; temp variables: ; byte r18 / r22 ; bitCnt r19 ; poly r20+r21 ; scratch r23 ; resCrc r24+r25 / r16+r17 ; ptr X / Z usbCrc16: mov ptrL, argPtrL mov ptrH, argPtrH ldi resCrcL, 0 ldi resCrcH, 0 ldi polyL, lo8(0xa001) ldi polyH, hi8(0xa001) com argLen ; argLen = -argLen - 1: modified loop to ensure that carry is set ldi bitCnt, 0 ; loop counter with starnd condition = end condition rjmp usbCrcLoopEntry usbCrcByteLoop: ld byte, ptr+ eor resCrcL, byte usbCrcBitLoop: ror resCrcH ; carry is always set here (see brcs jumps to here) ror resCrcL brcs usbCrcNoXor eor resCrcL, polyL eor resCrcH, polyH usbCrcNoXor: subi bitCnt, 224 ; (8 * 224) % 256 = 0; this loop iterates 8 times brcs usbCrcBitLoop usbCrcLoopEntry: subi argLen, -1 brcs usbCrcByteLoop usbCrcReady: ret ; Thanks to Reimar Doeffinger for optimizing this CRC routine! #endif /* USB_USE_FAST_CRC */ ; extern unsigned usbCrc16Append(unsigned char *data, unsigned char len); usbCrc16Append: rcall usbCrc16 st ptr+, resCrcL st ptr+, resCrcH ret #undef argLen #undef argPtrL #undef argPtrH #undef resCrcL #undef resCrcH #undef ptrL #undef ptrH #undef ptr #undef byte #undef bitCnt #undef polyL #undef polyH #undef scratch #if USB_CFG_HAVE_MEASURE_FRAME_LENGTH #ifdef __IAR_SYSTEMS_ASM__ /* Register assignments for usbMeasureFrameLength on IAR cc */ /* Calling conventions on IAR: * First parameter passed in r16/r17, second in r18/r19 and so on. * Callee must preserve r4-r15, r24-r29 (r28/r29 is frame pointer) * Result is passed in r16/r17 * In case of the "tiny" memory model, pointers are only 8 bit with no * padding. We therefore pass argument 1 as "16 bit unsigned". */ # define resL r16 # define resH r17 # define cnt16L r30 # define cnt16H r31 # define cntH r18 #else /* __IAR_SYSTEMS_ASM__ */ /* Register assignments for usbMeasureFrameLength on gcc */ /* Calling conventions on gcc: * First parameter passed in r24/r25, second in r22/23 and so on. * Callee must preserve r1-r17, r28/r29 * Result is passed in r24/r25 */ # define resL r24 # define resH r25 # define cnt16L r24 # define cnt16H r25 # define cntH r26 #endif # define cnt16 cnt16L ; extern unsigned usbMeasurePacketLength(void); ; returns time between two idle strobes in multiples of 7 CPU clocks .global usbMeasureFrameLength usbMeasureFrameLength: ldi cntH, 6 ; wait ~ 10 ms for D- == 0 clr cnt16L clr cnt16H usbMFTime16: dec cntH breq usbMFTimeout usbMFWaitStrobe: ; first wait for D- == 0 (idle strobe) sbiw cnt16, 1 ;[0] [6] breq usbMFTime16 ;[2] sbic USBIN, USBMINUS ;[3] rjmp usbMFWaitStrobe ;[4] usbMFWaitIdle: ; then wait until idle again sbis USBIN, USBMINUS ;1 wait for D- == 1 rjmp usbMFWaitIdle ;2 ldi cnt16L, 1 ;1 represents cycles so far clr cnt16H ;1 usbMFWaitLoop: in cntH, USBIN ;[0] [7] adiw cnt16, 1 ;[1] breq usbMFTimeout ;[3] andi cntH, USBMASK ;[4] brne usbMFWaitLoop ;[5] usbMFTimeout: #if resL != cnt16L mov resL, cnt16L mov resH, cnt16H #endif ret #undef resL #undef resH #undef cnt16 #undef cnt16L #undef cnt16H #undef cntH #endif /* USB_CFG_HAVE_MEASURE_FRAME_LENGTH */ ;---------------------------------------------------------------------------- ; Now include the clock rate specific code ;---------------------------------------------------------------------------- #ifndef USB_CFG_CLOCK_KHZ # ifdef F_CPU # define USB_CFG_CLOCK_KHZ (F_CPU/1000) # else # error "USB_CFG_CLOCK_KHZ not defined in usbconfig.h and no F_CPU set!" # endif #endif #if USB_CFG_CHECK_CRC /* separate dispatcher for CRC type modules */ # if USB_CFG_CLOCK_KHZ == 18000 # include "usbdrvasm18-crc.inc" # else # error "USB_CFG_CLOCK_KHZ is not one of the supported crc-rates!" # endif #else /* USB_CFG_CHECK_CRC */ # if USB_CFG_CLOCK_KHZ == 12000 # include "usbdrvasm12.inc" # elif USB_CFG_CLOCK_KHZ == 12800 # include "usbdrvasm128.inc" # elif USB_CFG_CLOCK_KHZ == 15000 # include "usbdrvasm15.inc" # elif USB_CFG_CLOCK_KHZ == 16000 # include "usbdrvasm16.inc" # elif USB_CFG_CLOCK_KHZ == 16500 # include "usbdrvasm165.inc" # elif USB_CFG_CLOCK_KHZ == 20000 # include "usbdrvasm20.inc" # else # error "USB_CFG_CLOCK_KHZ is not one of the supported non-crc-rates!" # endif #endif /* USB_CFG_CHECK_CRC */
