>-----Original Message----- >From: Alexey Starikovskiy [mailto:astarikovskiy@xxxxxxx] >Sent: Thursday, July 02, 2009 2:21 PM >To: Li, Shaohua >Cc: lenb@xxxxxxxxxx; linux-acpi@xxxxxxxxxxxxxxx >Subject: Re: EC > >Li, Shaohua пишет: >> Hi, >> Preempt isn't disabled between ec_burst_enable()/ec_burst_disable(), so >it's very likely there is a preemption between them and make the timing >for burst mode not comply with ACPI spec (400ms for first access and 50ms >for subsequent access). >> >> We have a system with broken EC and the BIOS engineer identified it's >the timing issue. >> What's the judgment why Linux doesn't comply with ACPI spec? > >Please disable ec_burst_* and check again. Judgement is that ec_burst_* is >irrelevant to the protocol. What did you about 'irrelevant to the protocol'? This is what the spec defines. >What platform and what other symptoms do you have? How exactly this EC is >broken? The temperature is wrong when we get it from reading EC. The BIOS engineer measured A lot of EC timeout in EC firmware, and they measured the timing how Linux accesses EC. The data they captured in oscilloscope shows Linux has long delay to access Ec with burst mode enabled, this occurs more often when another application is running. Thanks, Shaohua ��.n��������+%������w��{.n�����{�����ܨ}���Ơz�j:+v�����w����ޙ��&�)ߡ�a����z�ޗ���ݢj��w�f
