On 2/28/2017 6:03 AM, Patel, Mayurkumar wrote: >> - /* Save default state */ >> - link->aspm_default = link->aspm_enabled; > But, I am finding a problem with this change, if Policy is set to default, > BIOS enables ASPM L1, but pcie_config_aspm_link() disables ASPM L1 > due to link->aspm_enabled is different than link->aspm_default while > called from pcie_aspm_init_link_state() during hotplug insertion. >
Thanks for testing. I think it means the enable count logic I put below is not working. I was trying to figure out when to use saved values vs. the values in registers by looking at the enable_cnt. enable_cnt is 0 during boot on my system. The enable_cnt should have been non-zero following an insertion following remove and default and enabled values should have been identical. Can you print out the values of pdev->aspm_default, link->aspm_default, and link->aspm_enabled in this function along with atomic_read(&pdev->enable_cnt)? > >> + /* >> + * Save default state from FW when enabling ASPM for the first time >> + * during boot by looking at the calculated link->aspm_enabled bits >> + * above and enable_cnt will be zero. >> + * >> + * If this path is getting called for the second/third time >> + * (enable_cnt will be non-zero). Assume that the current state of the >> + * ASPM registers may not necessarily match what FW asked us to do as >> + * in the case of hotplug insertion/removal. >> + */ >> + if (!atomic_read(&pdev->enable_cnt)) >> + pdev->aspm_default = link->aspm_default = link->aspm_enabled; >> + else >> + link->aspm_default = pdev->aspm_default; -- Sinan Kaya Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
