[PATCH net-next] ionic: advertise 52-bit addressing limitation for MSI-X

David Christensen
2024-05-30T21:40:48Z

Current ionic devices only support 52 internal physical address
lines. This is sufficient for x86_64 systems which have similar
limitations but does not apply to all other architectures,
notably IBM POWER (ppc64). To ensure that MSI/MSI-X vectors are
not set outside the physical address limits of the NIC, set the
recently added no_64bit_msi value of the pci_dev structure
during device probe.

Signed-off-by: David Christensen <drc@linux.ibm.com>
---
drivers/net/ethernet/pensando/ionic/ionic_bus_pci.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_bus_pci.c b/drivers/net/ethernet/pensando/ionic/ionic_bus_pci.c
index 6ba8d4aca0a0..1e7f507f461f 100644
--- a/drivers/net/ethernet/pensando/ionic/ionic_bus_pci.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_bus_pci.c
@@ -326,6 +326,10 @@ static int ionic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
goto err_out;
}

+ /* Ensure MSI/MSI-X interrupts lie within addressable physical memory */
+ if (IONIC_ADDR_LEN < 64)
+ pdev->no_64bit_msi = 1;
+
err = ionic_setup_one(ionic);
if (err)
goto err_out;
--
2.43.0