powerpc/eeh: Block PCI config access during reset

Function pcibios_set_pcie_reset_state() can be used to do PCI
reset. PCI config access during the reset usually causes EEH
errors unexpectedly. In order to avoid the EEH error, the patch
blocks PCI config access during reset with the help of flag
EEH_PE_RESET, which is similar to what we did in EEH PE reset
path.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kernel/eeh.c

@@ -668,14 +668,18 @@ int pcibios_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state stat
 	switch (state) {
 	case pcie_deassert_reset:
 		eeh_ops->reset(pe, EEH_RESET_DEACTIVATE);
+		eeh_pe_state_clear(pe, EEH_PE_RESET);
 		break;
 	case pcie_hot_reset:
+		eeh_pe_state_mark(pe, EEH_PE_RESET);
 		eeh_ops->reset(pe, EEH_RESET_HOT);
 		break;
 	case pcie_warm_reset:
+		eeh_pe_state_mark(pe, EEH_PE_RESET);
 		eeh_ops->reset(pe, EEH_RESET_FUNDAMENTAL);
 		break;
 	default:
+		eeh_pe_state_clear(pe, EEH_PE_RESET);
 		return -EINVAL;
 	};