Re: [PATCH v5 1/5] PCI: designware: ensure ATU is enabled before IO/conf space accesses
From: Pratyush Anand <pratyush.anand@gmail.com>
Date: 2015-12-18 14:41:16
Also in:
linux-arm-kernel, linux-arm-msm, linux-pci, lkml
On Fri, Dec 18, 2015 at 6:08 PM, Stanimir Varbanov [off-list ref] 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 <redacted>
Acked-by: Pratyush Anand <pratyush.anand@gmail.com>