Date: Fri, 05 Jun 1998 13:46:27 -0700 From: Julian Elischer <julian@whistle.com> To: Shiaw Yi Hsieh <syhsieh@ali.com.tw>, johnson@ali.com.tw Cc: Hackers@FreeBSD.ORG Subject: Re: FreeBSD 2.2.x can't find SIO on ALi M5135 Message-ID: <35785923.2C67412E@whistle.com> References: <3577D9F3.80754AD7@ali.com.tw>
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Dear sir, I have forwarded your email to the people responsible for the Serial driver. However I had some trouble understanding your email. Your english is much better than my Chinese so please do not take this as a critisism, but as an attempt to clear some points that are unclear in the email. We are thrilled that our problems with the iWill motherboard have been taken seriously and will attempt to assist you in any way possible. I ask some questions below. Shiaw Yi Hsieh wrote: > > Dear sir, > Several month ago, one of our customers name Iwill feedback one > question: > FreeBSD 2.2.5 can not found UART port at Iwill motherboard (use Acer > labs. M5135). This parts is use Intel new technology name--serial IRQ. > and did not found any problem in the other parts such as M5113,M5123 AND > M1543. > And our R&D people made much effort to study how FreeBSD can not found > UART and Tape out a new version to fixed this issue(for 2.2.5). > But after we get the new chip we still have got the following issue: > > 1. FreeBSD boot from CD-ROM PASS > 2. FreeBSD boot from HDD PASS > 3 FreeBSD boot from FDD FAIL > > After we studied the different between boot from CD-ROM,HDD AND FDD > we found the different is in the command and command recovery time when > FreeBSD polling UART's IRQ(read IIR register 2fa,3fa,2ea,3ea). The > recovery time of CD-ROM,HDD is around several us but FDD command > recovery time only 2us. would it possible last the FDD commend recovery > time to over 10us? Your request is for FreeBSD to allow a longer time for IO recovery period after reading FDD registers? If so, then yes we can however, I have a difficulty understanding how the speed of accessing FDD registers affects access to the Serial ports? > Maybe Serial IRQ will take more time when set IIR register and read 8259 > to get the status, so we recommend OS polling or read those IIR register > it is better to last the recovery time to get the 8259 IRQ status. You are saying: we should wait longer to find the interrupt, and maybe poll the IIR register to see if the interrupt has been made? > Another issue is read 8259 IRQ status method, in the parallel IRQ you > can read from edge or level but NEW serial IRQ our chip M5135 only have > got a pulse and not the level. Maybe this is why FreeBSD can not found > UART. possibly. You say that the parallel-Port IRQ and the serial-port IRQ on the same chip behave differently? Surely the serial IRQ must act the same a National Semiconductor NS16450 for compatibility? > Our new chip had been option to change the IRQ from pulse to level, but > in FDD boot still have this issue. Do you have any comments? It is surprising that the FDD boot behaves differently. there is no code difference in FreeBSD if booted from FDD. Maybe the BIOS adjusts the ISA-BUS IO-recover time during FDD operations? After FreeBSD starts, BIOS is disabled so any settings by the BIOS are frozen at that time. > And FreeBSD > test have been put in our chip verify item, so if you release new > version, please mail to us for testting. Thankyou for your assistance! > > If you have any comments please contact me: johnson@ali.com.tw > > Thanks > > JOHNSON CHEN / MANAGER Acer Labs. Inc > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-questions" in the body of the message To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
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