Re: [PATCH v5 1/5] PCI: designware: ensure ATU is enabled before IO/conf space accesses

From: Pratyush Anand
Date: Fri Dec 18 2015 - 09:41:20 EST


On Fri, Dec 18, 2015 at 6:08 PM, Stanimir Varbanov
<stanimir.varbanov@xxxxxxxxxx> wrote:
> There is no guarantees that enabling ATU will hit the hardware
> immediately, and subsequent accesses to configuration / IO spaces
> are reliable. So fixing this by read back PCIE_ATU_CR2 register
> just after writing.
>
> Without such a fix the PCI device enumeration during kernel boot
> is not reliable, and reading configuration space for particular
> PCI device on the bus returns zero aka no device.
>
> Signed-off-by: Stanimir Varbanov <stanimir.varbanov@xxxxxxxxxx>

Acked-by: Pratyush Anand <pratyush.anand@xxxxxxxxx>
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