RE: [t13] SATA Async loss vs HRESET... settings of the drive

[Mark Overby]

Title: Message

It is not a catastrophic condition to lose signal. A poor cable, noise, and even software initiated PHY events can cause loss of signal and heads right into COMRESET.   -----Original Message----- From: Gary Laatsch [mailto:[EMAIL PROTECTED] Sent: Saturday, September 20, 2003 3:07 PM To: Wolford, Jeff; ATA T13 Reflector Subject: Re: [t13] SATA Async loss vs HRESET... settings of the drive   For background and clarification purposes, since some of us are a little out of the loop these days.  What condition(s) could lead to Async loss of signal?  Is this a catastrophic condition (i.e. unlikely but possible) or just an occasional emotional issue (hiccup) on the interface? This could aid in the suggestion of possible solutions.   Gary Laatsch [EMAIL PROTECTED] ----- Original Message ----- From: Wolford, Jeff To: ATA T13 Reflector Sent: Saturday, September 20, 2003 10:26 AM Subject: [t13] SATA Async loss vs HRESET... settings of the drive   And now for a tough one to solve...   SUMMARY:     What happens to the soft settings of a drive during a Async loss of signal ?      (such as UDMA mode, IDP values, Multi settings or any other setfeat soft setting)   SUGGESTION: Drives need to know the difference between a Async loss of signal and a commanded COMRESET. If it is a Async loss of signal, they need to maintain the "soft settings", if its a commanded COMRESET, they need to reset all the settings and expect the OS to reprogram them   BACKGROUND: On SATA Comreset is equated to HRESET on PATA.  Also Async loss of signal on SATA is equated to COMRESET.... HOWEVER, there is a problem (ok only one -:) with this assumption.   On PATA HRESET happens VERY view times (at boot, commanded reboot and coming out of S3 and S4).  Each of these times the OS / BIOS is VERY aware that this is happening.   HOWEVER, on SATA Async loss of signal is NOT commanded and the OS is NOT very aware and has NO was of knowing if it is not VERY SATA aware (aka the OS would have to poll the SATA SERROR / SSTATUS non-standard location registers).   Thus the OS does not know to comedown and reprogram the drive with the right UDMA mode, multi setting for read multiple, IDP values, etc).   CURRENT SITUATION:   Several SATA drives on the market today will totally lock up and a SRST will NOT get them out of this condition.   Example 1:  On a Async loss of signal, Several drives will reset the PATA portion (thus loose the soft setting of DMA mode and revert back to multiword DMA), the SATA to PATA conversion portion is fixed in UDMA mode...  BINGO... LOCK up   Example 2: BIOS / OS setup a multi setting of 16 for a read / write multiple.  Then a ASYNC loss of signal, multi reverts back to 1 or something other than 16 on the drive.  OS does a write multi... BINGO Lock up   .... And the list goes on.   All soft settings need to be addressed.   Jeff   Jeff Wolford                       Email: [EMAIL PROTECTED] Senior Architect Storage Interface and Tools -  Business PC Products  Group     Voice: (281) 514-9465,     Pager: (800) 973-5739 Hewlett-Packard Corporation