Messages in this thread | | | Subject | Re: [PATCH v2 1/5] bus: mhi: core: Handle syserr during power_up | From | Jeffrey Hugo <> | Date | Wed, 22 Apr 2020 14:16:02 -0600 |
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On 4/21/2020 12:08 AM, Manivannan Sadhasivam wrote: > On Mon, Apr 13, 2020 at 08:01:36AM -0600, Jeffrey Hugo wrote: >> On 4/13/2020 7:34 AM, Manivannan Sadhasivam wrote: >>> On Fri, Apr 10, 2020 at 03:39:57PM -0600, Jeffrey Hugo wrote: >>>> On 4/10/2020 2:37 PM, Bhaumik Vasav Bhatt wrote: >>>>> Hi Jeff, >>>>> >>>>> We will always have the mhi_intvec_handler registered and trigger your >>>>> wake_up state event when you write MHI RESET. BHI INTVEC IRQ using >>>>> mhi_cntrl->irq[0] is _not_ unregistered once you enter AMSS EE. >>>> >>>> I understand it is not unregistered. However mhi_cntrl->irq[0] may be >>>> reserved for BHI, and thus only exercised by PBL EE. Where as, >>>> mhi_cntrl->irq[1..N] may be only exercised by AMSS EE. mhi_intvec_handler is >>>> not called in response to mhi_cntrl->irq[1..N]. >>>> >>>> Additionally, I re-reviewed the MHI spec, and I don't see where the spec >>>> requires the device to issue an interrupt upon completion of the RESET >>>> request. >>>> >>>> Under section 3.5, step 11 states - >>>> >>>> "The host must poll for the value of the RESET bit to detect the completion >>>> of the reset procedure by the device (RESET is set to 0)." >>>> >>> >>> If this is the scenario then we need to change all of the wait_event_timeout() >>> implementation for MHI RESET in current stack to polling. >>> >>> Or the interrupt generation is not defined in spec (sheet) but part of the >>> existing implementation? >> >> It probably could be considered part of the existing implementation, but I'd >> like to hear from Hemant/Bhaumik. Wherever we end up, I'd like to have the >> spec match. > > Hemant/Bhaumik, can you please share your thoughts?
Sorry. Hemant, Bhaumik, and I have had a few calls discussing this. We are trying to come to a consensus on the expectation of the device behavior, so that we can propose the best solution. Probably a few more days yet while we await for a bit of clarification.
-- Jeffrey Hugo Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
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