[PATCH] powerpc/powernv/pci: Do setup dev PE in pnv_pci_enable_device_hook

[Luming Yu]

after hot remove a pcie deivce with pci_dn having pnp_php driver attached,
pci rescan with echo 1 > /sys/bus/pci/rescan could fail with error
message like:
pci 0020:0e:00.0: BAR 0: assigned [mem 0x3fe801820000-0x3fe80182ffff
64bit]
nvme nvme1: pci function 0020:0e:00.0
nvme 0020:0e:00.0 pci_enable_device() blocked, no PE assigned.

It appears that the pci_dn object is reused with only pe_number
clobbered in the case. And a simple call to pnv_ioda_setup_dev_PE should
get PE number back and solve the problem.

Signed-off-by: Luming Yu <luming.yu at shingroup.cn>
---
 arch/powerpc/platforms/powernv/pci-ioda.c     |  11 +-
 drivers/gpu/drm/nouveau/nvkm/subdev/i2c/aux.c | 215 ------------------
 drivers/gpu/drm/nouveau/nvkm/subdev/i2c/aux.h |  46 ----
 include/soc/arc/aux.h                         |  59 -----
 4 files changed, 9 insertions(+), 322 deletions(-)
 delete mode 100644 drivers/gpu/drm/nouveau/nvkm/subdev/i2c/aux.c
 delete mode 100644 drivers/gpu/drm/nouveau/nvkm/subdev/i2c/aux.h
 delete mode 100644 include/soc/arc/aux.h

diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 28fac4770073..9d7add79ee3d 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -2325,11 +2325,18 @@ static resource_size_t pnv_pci_default_alignment(void)
 static bool pnv_pci_enable_device_hook(struct pci_dev *dev)
 {
 	struct pci_dn *pdn;
+	struct pnv_ioda_pe *pe;
 
 	pdn = pci_get_pdn(dev);
-	if (!pdn || pdn->pe_number == IODA_INVALID_PE) {
-		pci_err(dev, "pci_enable_device() blocked, no PE assigned.\n");
+	if (!pdn)
 		return false;
+
+	if (pdn->pe_number == IODA_INVALID_PE) {
+		pe = pnv_ioda_setup_dev_PE(dev);
+		if (!pe) {
+			pci_err(dev, "pci_enable_device() blocked, no PE assigned.\n");
+			return false;
+		}
 	}
 
 	return true;