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Diffstat (limited to 'vusb/usbdrv/usbdrvasm.S')
| -rw-r--r-- | vusb/usbdrv/usbdrvasm.S | 393 |
1 files changed, 393 insertions, 0 deletions
diff --git a/vusb/usbdrv/usbdrvasm.S b/vusb/usbdrv/usbdrvasm.S new file mode 100644 index 0000000000..45fcf18315 --- /dev/null +++ b/vusb/usbdrv/usbdrvasm.S @@ -0,0 +1,393 @@ +/* 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) + * Revision: $Id: usbdrvasm.S 785 2010-05-30 17:57:07Z cs $ + */ + +/* +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 */ |