Re: A question about state machine function state_next()

[Joerg Roedel]

On Mon, Jun 01, 2015 at 07:18:02PM +0800, Baoquan He wrote:
> Checked the code again, it may be a code bug if this is done in
> device_dma_ops_init(). Since this is called in
> amd_iommu_init_dma_ops()<-amd_iommu_init_dma(). And amd_iommu_init_dma()
> is only called in case IOMMU_INTERRUPTS_EN code block. According to the
> code flow if I understand correctly, it can't be here at boot stage.
> state_next() will change the state according to the calling times. And
> in amd iommu only four times to call iommu_go_to_state, it can't go to
> IOMMU_PCI_INIT and the after cases.
> 
> I am not sure if my understanding is correct, or I missed something.

You probably missed the loop in iommu_go_to_state() which will call
state_next() until it reaches either the requested state or an error
state.


	Joerg

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