openwrt/target/linux/generic/backport-5.10/821-v5.13-let-pci-host-bridges-declar-their-reliance-on-msi-domains.patch
Nick Hainke e8e2b88f5f mediatek: mt7623: import patch to fix msi warning
The 1st generation MediaTek PCIe host bridge cannot handle Message
Signaled Interrupts (MSIs). The core PCI code is not aware that MSI is
not available. This results in warnings of the form:

WARNING: CPU: 2 PID: 112 at include/linux/msi.h:219
  pci_msi_setup_msi_irqs.constprop.8+0x64/0x6c
Modules linked in: ahci(+) libahci libata sd_mod scsi_mod
  gpio_button_hotplug
CPU: 2 PID: 112 Comm: kmodloader Not tainted 5.10.52 #0
Hardware name: Mediatek Cortex-A7 (Device Tree)

Import patches that introduce the 'no_msi' attribute to signal missing
MSI support to the core PCI.

Refresh patches:
- 000-spi-fix-fifo.patch
- 330-mtk-bmt-support.patch
- 510-net-mediatek-add-flow-offload-for-mt7623.patch
- 601-PCI-mediatek-Use-regmap-to-get-shared-pcie-cfg-base.patch
- 610-pcie-mediatek-fix-clearing-interrupt-status.patch
- 700-net-ethernet-mtk_eth_soc-add-support-for-coherent-DM.patch
- 710-pci-pcie-mediatek-add-support-for-coherent-DMA.patch

Signed-off-by: Nick Hainke <vincent@systemli.org>
2021-07-29 15:08:17 +01:00

45 lines
1.7 KiB
Diff

From 94e89b145371b68fa0ea294855adebcd03e0522e Mon Sep 17 00:00:00 2001
From: Marc Zyngier <maz@kernel.org>
Date: Tue, 30 Mar 2021 16:11:41 +0100
Subject: PCI/MSI: Let PCI host bridges declare their reliance on MSI domains
There is a whole class of host bridges that cannot know whether
MSIs will be provided or not, as they rely on other blocks
to provide the MSI functionnality, using MSI domains. This is
the case for example on systems that use the ARM GIC architecture.
Introduce a new attribute ('msi_domain') indicating that implicit
dependency, and use this property to set the NO_MSI flag when
no MSI domain is found at probe time.
Link: https://lore.kernel.org/r/20210330151145.997953-11-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
---
drivers/pci/probe.c | 2 ++
include/linux/pci.h | 1 +
2 files changed, 3 insertions(+)
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -925,6 +925,8 @@ static int pci_register_host_bridge(stru
device_enable_async_suspend(bus->bridge);
pci_set_bus_of_node(bus);
pci_set_bus_msi_domain(bus);
+ if (bridge->msi_domain && !dev_get_msi_domain(&bus->dev))
+ bus->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
if (!parent)
set_dev_node(bus->bridge, pcibus_to_node(bus));
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -545,6 +545,7 @@ struct pci_host_bridge {
unsigned int native_dpc:1; /* OS may use PCIe DPC */
unsigned int preserve_config:1; /* Preserve FW resource setup */
unsigned int size_windows:1; /* Enable root bus sizing */
+ unsigned int msi_domain:1; /* Bridge wants MSI domain */
/* Resource alignment requirements */
resource_size_t (*align_resource)(struct pci_dev *dev,