[PATCH 6.19 421/781] PCI: Add ACS quirk for Pericom PI7C9X2G404 switches [12d8:b404]

Greg Kroah-Hartman
2026-02-25T01:34:44Z

From: Nicolas Cavallari <nicolas.cavallari@green-communications.fr>

[ Upstream commit 5907a90551e9f7968781f3a6ab8684458959beb3 ]

12d8:b404 is apparently another PCI ID for Pericom PI7C9X2G404 (as
identified by the chip silkscreen and lspci).

It is also affected by the PI7C9X2G errata (e.g. a network card attached
to it fails under load when P2P Redirect Request is enabled), so apply
the same quirk to this PCI ID too.

PCI bridge [0604]: Pericom Semiconductor PI7C9X2G404 EV/SV PCIe2 4-Port/4-Lane Packet Switch [12d8:b404] (rev 01)

Fixes: acd61ffb2f16 ("PCI: Add ACS quirk for Pericom PI7C9X2G switches")
Closes: https://lore.kernel.org/all/a1d926f0-4cb5-4877-a4df-617902648d80@green-communications.fr/
Signed-off-by: Nicolas Cavallari <nicolas.cavallari@green-communications.fr>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20260119160915.26456-1-nicolas.cavallari@green-communications.fr
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/pci/quirks.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 211b7f72d103e..6df78efd7f6dc 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -6189,6 +6189,10 @@ DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_PERICOM, 0x2303,
pci_fixup_pericom_acs_store_forward);
DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_PERICOM, 0x2303,
pci_fixup_pericom_acs_store_forward);
+DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_PERICOM, 0xb404,
+ pci_fixup_pericom_acs_store_forward);
+DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_PERICOM, 0xb404,
+ pci_fixup_pericom_acs_store_forward);

static void nvidia_ion_ahci_fixup(struct pci_dev *pdev)
{
--
2.51.0