openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

Revert "powerpc/powernv: Exclude root bus in pnv_pci_reset_secondary_bus()" 

This reverts commit c8ceacc22b.

Gavin says: I missed the fact that it affects the PCI passthrou path as
reported by Alexey: When passing GPU (0003:01:00.0) which seats behind
the root port, the reset request is routed to skiboot in original code.
In skiboot, the link bouncing events are masked during the reset. So we
don't see EEH (freeze all) error even link bouncing happens. With the
changes included, the reset is done by kernel and the link bouncing
events aren't masked by altering content of PHB3 (or P7IOC) specific
hardware registers which are invisible to kernel (skiboot hides the
hardware specific). It means the link bouncing is seen by the root port
and it causes a EEH (freeze all) error. The PCI passthrough on GPU
device cannot work.

Requested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Requested-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Michael Ellerman 2016-05-12 19:43:37 +10:00
parent b5cb9ab1a0
commit 848912e547
1 changed files with 10 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
arch/powerpc/platforms/powernv/eeh-powernv.c
View File

@ -868,8 +868,16 @@ static int pnv_eeh_bridge_reset(struct pci_dev *dev, int option)
void pnv_pci_reset_secondary_bus(struct pci_dev *dev)
{
pnv_eeh_bridge_reset(dev, EEH_RESET_HOT);
pnv_eeh_bridge_reset(dev, EEH_RESET_DEACTIVATE);
struct pci_controller *hose;
if (pci_is_root_bus(dev->bus)) {
hose = pci_bus_to_host(dev->bus);
pnv_eeh_root_reset(hose, EEH_RESET_HOT);
pnv_eeh_root_reset(hose, EEH_RESET_DEACTIVATE);
} else {
pnv_eeh_bridge_reset(dev, EEH_RESET_HOT);
pnv_eeh_bridge_reset(dev, EEH_RESET_DEACTIVATE);
}
}
static void pnv_eeh_wait_for_pending(struct pci_dn *pdn, const char *type,