[PATCH] powerpc/powernv: Escalate reset when IODA reset fails

[Alexey Kardashevskiy]

On 01/02/2019 11:42, Oliver O'Halloran wrote:
> The IODA reset is used to flush out any OS controlled state from the PHB.
> This reset can fail if a PHB fatal error has occurred in early boot,
> probably due to a because of a bad device. We already do a fundemental
> reset of the device in some cases, so this patch just adds a test to force
> a full reset if firmware reports an error when performing the IODA reset.
> 
> Signed-off-by: Oliver O'Halloran <oohall at gmail.com>

I am pretty sure I already saw this :-/

ah, anyway

Reviewed-by: Alexey Kardashevskiy <aik at ozlabs.ru>




> ---
>  arch/powerpc/platforms/powernv/pci-ioda.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
> index 1d6406a..53982f8 100644
> --- a/arch/powerpc/platforms/powernv/pci-ioda.c
> +++ b/arch/powerpc/platforms/powernv/pci-ioda.c
> @@ -3943,9 +3943,12 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np,
>  	 * shutdown PCI devices correctly. We already got IODA table
>  	 * cleaned out. So we have to issue PHB reset to stop all PCI
>  	 * transactions from previous kernel. The ppc_pci_reset_phbs
> -	 * kernel parameter will force this reset too.
> +	 * kernel parameter will force this reset too. Additionally,
> +	 * if the IODA reset above failed then use a bigger hammer.
> +	 * This can happen if we get a PHB fatal error in very early
> +	 * boot.
>  	 */
> -	if (is_kdump_kernel() || pci_reset_phbs) {
> +	if (is_kdump_kernel() || pci_reset_phbs || rc) {
>  		pr_info("  Issue PHB reset ...\n");
>  		pnv_eeh_phb_reset(hose, EEH_RESET_FUNDAMENTAL);
>  		pnv_eeh_phb_reset(hose, EEH_RESET_DEACTIVATE);
> 

-- 
Alexey