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by astezheng - C/C++ - 2009-04-08 13:39:28 ÔĶÁ£¨1743£© »Ø¸´£¨10£©

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by drewasdrew - LinuxÂÛ̳ - 2004-07-07 21:58:42 ÔĶÁ£¨333£© »Ø¸´£¨0£©

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by yongwenli2008 - ´æ´¢ÎĵµÖÐÐÄ - 2008-10-21 23:25:55 ÔĶÁ£¨1090£© »Ø¸´£¨0£©

ʲôÊÇdma£¿ µ±ÎÒÃÇÏò¼ÆËã»úÖмÓÈëÁËÒ»¿éеÄÉù¿¨»òÆäËüÊÊÅ俨ʱ£¬°²×°³ÌÐò¿ÉÄÜ»áÌáÐÑÎÒÃÇÓ¦¸ÃÑ¡ÔñÒ»¸ödmaͨµÀ¡£ÄÇdmaÊÇÊ²Ã´ÄØ? dma£¨Direct Memory Access£©£¬¼´Ö±½Ó´æ´¢Æ÷´æÈ¡£¬ÊÇÒ»ÖÖ¿ìËÙ´«ËÍÊý¾ÝµÄ»úÖÆ¡£Êý¾Ý´«µÝ¿ÉÒÔ´ÓÊÊÅ俨µ½Äڴ棬´ÓÄÚ´æµ½ÊÊÅ俨»ò´ÓÒ»¶ÎÄÚ´æµ½ÁíÒ»¶ÎÄÚ´æ¡£dma¼¼ÊõµÄÖØÒª ÐÔÔÚÓÚ£¬ÀûÓÃËü½øÐÐÊý¾Ý´«ËÍʱ²»ÐèÒªCPUµÄ²ÎÓ롣ÿ̨µçÄÔÖ÷»ú°åÉ϶¼ÓÐdma¿ØÖÆÆ÷£¬Í¨³£¼ÆËã»ú¶ÔÆä±à³Ì£¬²¢ÓÃÒ»¸öÊÊÅäÆ÷ÉϵÄROM(ÈçÈíÅÌ...

by zhangyanwei37 - ´æ´¢ÎĵµÖÐÐÄ - 2008-07-30 15:00:57 ÔĶÁ£¨658£© »Ø¸´£¨0£©

×òÍí¿ªÊ¼»ú·¿bsd62Á¬²»Í¨,ÖÐÎç½øÈ¥Ò»¿´,ÂúÆÁµÄ¹ØÓÚ/dev/ad3 read_dmaµÄÐÅÏ¢. ÖØÆôfsck -yºóÕý³£Æô¶¯,ÏÂÃæÊǹØÓÚsmartctlµÄÐÅÏ¢,ÊDz»ÊÇÓ²ÅÌÓÐÎÊÌâÄØ? **** bsd62# smartctl -H /dev/ad3 smartctl version 5.36 [i386-portbld-freebsd6.2] Copyright (C) 2002-6 Bruce Allen Home page is http://smartmontools.sourceforge.net/ === START OF READ SMART DATA SECTION === SMART overall-health self-assessment test result: P...

by ´ò°Ð¹éÀ´ - BSD - 2007-06-04 15:48:31 ÔĶÁ£¨1647£© »Ø¸´£¨2£©

µÚ9Õ ¡¡dma 9.1 dma£ºÊ²Ã´ÊÇdma£¬ËüÈçºÎ¹¤×÷ Copyright © 1995,1997 Frank Durda IV , All Rights Reserved. 10 December 1996. Last Update 8 October 1997. ·­Òë gvim Ô­ÎÄÁ¬½Ó http://www.freebsd.org/doc/en_US.ISO8859-1/books/developers-handbook/dma.html Ö±½ÓÄÚ´æ·ÃÎÊ(dma)ÊÇÒ»ÖÖ´«ÊäÊý¾ÝµÄ·½Ê½£¬ËüÔÊÐíÁ½¸öµØÖ·ÉϵÄÊý¾ÝÖ±½Ó½øÐд«Êä¶øÎÞÐèCPUµÄ½éÈë¡£ dma¹¦ÄÜÔÚ²»Í¬¼ÆËã»úÌåϵϵÄʵÏÖ·½Ê½ÓÐËù²»Í¬£¬Òò´Ë...

by gvim - BSDÎĵµÖÐÐÄ - 2007-03-12 08:42:43 ÔĶÁ£¨1377£© »Ø¸´£¨0£©

ÏÂÃæµÄÕâ¶Î»°Õª×Ô»¥ÁªÍøÉÏ,ÎҸ㲻¶®"ʵ¼ÊµÄ´«ÊäÒ²²»½èÖúÂýËÙµÄISA dmaCÀ´½øÐÐ,¶øÊÇÓÉÄÚǶÔÚPCI¿¨ÖеÄdmaµç·£¨±È´«Í³µÄISA dmaCÒª¿ì£©À´Íê³É"Õâ¾ä»°µÄÒâ˼,ÄѵÀÊÇ˵ÿ¸öPCI¿¨É϶¼ÓÐÒ»¸ödmaC? dmaÊÇÍâÉèÓëÖ÷´æÖ®¼äµÄÒ»ÖÖÊý¾Ý´«Êä»úÖÆ¡£Ò»°ãÀ´Ëµ£¬ÍâÉèÓëÖ÷´æÖ®¼ä´æÔÚÁ½ÖÖÊý¾Ý´«Êä·½·¨£º£¨1£©Pragrammed I/O£¨PIO£©·½·¨£¬Ò²¼´ÓÉCPUͨ¹ýÄÚ´æ¶ÁдָÁî»òI/OÖ¸ÁîÀ´³ÖÐøµØ¶ÁдÍâÉèµÄÄÚ´æµ¥Ôª£¨8λ¡¢16λ»ò32룩£¬Ö±µ½Õû¸öÊý¾Ý´«Êä¹ý³ÌÍê³É...

by qtdszws - ÄÚºË/ǶÈë¼¼Êõ - 2006-04-11 08:52:30 ÔĶÁ£¨1650£© »Ø¸´£¨5£©

ÔÚÇý¶¯Àï×öÒ»´ÎÓ²ÅÌdma²Ù×÷,ûÓÐÖжϲúÉú, ×ÜÊdz¬Ê±. ÄÄλ¸øµã½¨Òé, ¿´¿´ÎÒÒÅ©ÁËʲô²½Öè? ÎҵĹý³Ì´ó¸ÅÈçÏÂ. ¶ÁÃüÁî: ×¼±¸s/g table, °Ñs/g table µØÖ·Ð´Èës/gÖ¸Õë¼Ä´æÆ÷ дLBA & command register Çå³ýÖжÏ/´íÎó¼Ä´æÆ÷ È·¶¨¶Áд·½Ïò, ²¢Æô¶¯dma ÒÔÉϼ¸¸ö²½Öè, ÎÒ·´¸´È·ÈϹý, ¿´²»³öÓдíÎó. ´úÂëÓе㳤(>1000lines), Ë¡²»Ìù³öÀ´ÁË. ÔÚ³¬Ê±´¦Àíº¯ÊýÀï, ¶Á״̬¼Ä´æÆ÷, ·¢ÏÖdma²Ù×÷²¢Ã»ÓÐÍê³É. ¸÷λ¸øµã½¨Òé,ÏÈл¹ýÁË

by yidou - ÄÚºË/ǶÈë¼¼Êõ - 2006-04-07 09:32:31 ÔĶÁ£¨614£© »Ø¸´£¨2£©

os redhat 7.3 ³öÏÖÁËÏÂÁдíÎó£¬ÇëÎÊ¿ÉÄÜÊÇʲôԭÒòÔì³ÉµÄ£¬Ð»Ð»´ó¼Ò dma_timer_expiry: dma status == 0x20

by ·É»ðÁ÷ÐÇ - LinuxÂÛ̳ - 2005-01-25 17:21:19 ÔĶÁ£¨317£© »Ø¸´£¨0£©

dmaµÄÒâ˼ÊÇÖ±½ÓÄÚ´æ·ÃÎÊ.Õâ¸ö¹¦ÄÜËõ¶Ì³ÌÐò¶Ô´¦Àí»úµÄÕ¼ÓÃʱ¼ä. :?:

by Myheart - BSD - 2004-09-30 11:11:24 ÔĶÁ£¨1217£© »Ø¸´£¨3£©

ÊäÈë# hdparm -d1 /dev/hdaºóÏÔʾ /dev/hda: setting using_dma to 1 (on) HDIO_SET_dma failed: Operation not permitted using_dma = 0 (off) ÇëÎÊÔõô°ì?

by M×Ð - LinuxÂÛ̳ - 2003-03-31 10:08:46 ÔĶÁ£¨408£© »Ø¸´£¨3£©