lkml.org 
[lkml]   [2020]   [Nov]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: Aw: Re: Re: [PATCH] pci: mediatek: fix warning in msi.h
On 2020-11-04 23:14, Thomas Gleixner wrote:

[...]

> TBH, that's butt ugly. So after staring long enough into the PCI code I
> came up with a way to transport that information to the probe code.
>
> That allows a particular device to say 'I can't do MSI' and at the same
> time keeps the warning machinery intact which tells us that a
> particular
> host controller driver is broken.
>
> Uncompiled and untested as usual :)
>
> Thanks,
>
> tglx
> ---
> drivers/pci/controller/pcie-mediatek.c | 4 ++++
> drivers/pci/probe.c | 3 +++
> include/linux/pci.h | 1 +
> 3 files changed, 8 insertions(+)
>
> --- a/drivers/pci/controller/pcie-mediatek.c
> +++ b/drivers/pci/controller/pcie-mediatek.c
> @@ -143,6 +143,7 @@ struct mtk_pcie_port;
> * struct mtk_pcie_soc - differentiate between host generations
> * @need_fix_class_id: whether this host's class ID needed to be fixed
> or not
> * @need_fix_device_id: whether this host's device ID needed to be
> fixed or not
> + * @no_msi: Bridge has no MSI support
> * @device_id: device ID which this host need to be fixed
> * @ops: pointer to configuration access functions
> * @startup: pointer to controller setting functions
> @@ -151,6 +152,7 @@ struct mtk_pcie_port;
> struct mtk_pcie_soc {
> bool need_fix_class_id;
> bool need_fix_device_id;
> + bool no_msi;
> unsigned int device_id;
> struct pci_ops *ops;
> int (*startup)(struct mtk_pcie_port *port);
> @@ -1084,6 +1086,7 @@ static int mtk_pcie_probe(struct platfor
>
> host->ops = pcie->soc->ops;
> host->sysdata = pcie;
> + host->no_msi = pcie->soc->no_msi;
>
> err = pci_host_probe(host);
> if (err)
> @@ -1173,6 +1176,7 @@ static const struct dev_pm_ops mtk_pcie_
> };
>
> static const struct mtk_pcie_soc mtk_pcie_soc_v1 = {
> + .no_msi = true,
> .ops = &mtk_pcie_ops,
> .startup = mtk_pcie_startup_port,
> };
> --- a/drivers/pci/probe.c
> +++ b/drivers/pci/probe.c
> @@ -889,6 +889,9 @@ static int pci_register_host_bridge(stru
> if (!bus)
> return -ENOMEM;
>
> + if (bridge->no_msi)
> + bus->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
> +
> bridge->bus = bus;
>
> /* Temporarily move resources off the list */
> --- 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 no_msi:1; /* Bridge has no MSI support */
>
> /* Resource alignment requirements */
> resource_size_t (*align_resource)(struct pci_dev *dev,

If that's the direction of travel, we also need something like this
for configuration where the host bridge relies on an external MSI block
that uses MSI domains (boot-tested in a GICv3 guest).

M.

diff --git a/drivers/pci/controller/pci-host-common.c
b/drivers/pci/controller/pci-host-common.c
index 6ce34a1deecb..603f6fbbe68a 100644
--- a/drivers/pci/controller/pci-host-common.c
+++ b/drivers/pci/controller/pci-host-common.c
@@ -77,6 +77,7 @@ int pci_host_common_probe(struct platform_device
*pdev)

bridge->sysdata = cfg;
bridge->ops = (struct pci_ops *)&ops->pci_ops;
+ bridge->msi_domain = true;

platform_set_drvdata(pdev, bridge);

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 16fb150fbb8d..f421b2869bca 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -889,9 +889,6 @@ static int pci_register_host_bridge(struct
pci_host_bridge *bridge)
if (!bus)
return -ENOMEM;

- if (bridge->no_msi)
- bus->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
-
bridge->bus = bus;

/* Temporarily move resources off the list */
@@ -928,6 +925,9 @@ static int pci_register_host_bridge(struct
pci_host_bridge *bridge)
device_enable_async_suspend(bus->bridge);
pci_set_bus_of_node(bus);
pci_set_bus_msi_domain(bus);
+ if (bridge->no_msi ||
+ (bridge->msi_domain && !bus->dev.msi_domain))
+ bus->bus_flags |= PCI_BUS_FLAGS_NO_MSI;

if (!parent)
set_dev_node(bus->bridge, pcibus_to_node(bus));
diff --git a/include/linux/pci.h b/include/linux/pci.h
index c2a0c1d471d6..81f72fd46e06 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -546,6 +546,7 @@ struct pci_host_bridge {
unsigned int preserve_config:1; /* Preserve FW resource setup */
unsigned int size_windows:1; /* Enable root bus sizing */
unsigned int no_msi:1; /* Bridge has no MSI support */
+ unsigned int msi_domain:1; /* Bridge wants MSI domain */

/* Resource alignment requirements */
resource_size_t (*align_resource)(struct pci_dev *dev,
--
Jazz is not dead. It just smells funny...

\
 
 \ /
  Last update: 2020-11-05 10:20    [W:0.071 / U:0.284 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site