[PATCH 2/2] arm64: a37xx: pci: Assert PERST# signal when unloading driver

[Andre Heider]

On 19/08/2020 15:57, Pali Rohár wrote:
> This change ensures that PCIe card is put into reset state when U-Boot
> stops using it.
> 
> DM_FLAG_OS_PREPARE ensures that U-Boot executes driver's remove callback
> prior booting Linux kernel.
> 
> Linux kernel pci-aardvark driver needs to reset PCIe card via PERST# signal
> prior initializing it. If it does not issue reset then some PCIe cards
> (specially Compex WiFi cards) are not detected at all.
> 
> Putting PCIe card into reset state prior booting Linux kernel would ensure
> that card would be properly reset at time when Linux kernel starts
> initializing pci-aardvark driver.
> 
> Signed-off-by: Pali Rohár <pali at kernel.org>

Tested-by: Andre Heider <a.heider at gmail.com>