* [PATCH 1/2] PCI: dwc-host: Add a warning to prevent invalid values
@ 2022-11-07 15:31 JunDong Song
2022-11-07 15:31 ` [PATCH 2/2] " JunDong Song
2022-11-10 21:32 ` [PATCH 1/2] " Bjorn Helgaas
0 siblings, 2 replies; 3+ messages in thread
From: JunDong Song @ 2022-11-07 15:31 UTC (permalink / raw)
To: jingoohan1, gustavo.pimentel, lpieralisi
Cc: robh, kw, bhelgaas, linux-pci, linux-kernel, JunDong Song
of_pci_get_max_link_speed() may return a negative value,
causing the controller to not set the speed correctly.
Add a warning in case the driver engineer misses it.
Signed-off-by: JunDong Song <jundongsong1@gmail.com>
---
When I use the pcie dwc driver, the controller speed is abnormal,
but it has not been detected because of the @max-link-speed error,
so I think I need to return an error or warning here.
Thanks.
drivers/pci/controller/dwc/pcie-designware-ep.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 83ddb1902..573342601 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -739,8 +739,11 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
return -ENOMEM;
ep->outbound_addr = addr;
- if (pci->link_gen < 1)
+ if (pci->link_gen < 1) {
pci->link_gen = of_pci_get_max_link_speed(np);
+ if (unlikely(pci->link_gen < 0))
+ dev_warn(dev, "Failed to get max link speed\n");
+ }
epc = devm_pci_epc_create(dev, &epc_ops);
if (IS_ERR(epc)) {
--
2.25.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH 2/2] PCI: dwc-host: Add a warning to prevent invalid values
2022-11-07 15:31 [PATCH 1/2] PCI: dwc-host: Add a warning to prevent invalid values JunDong Song
@ 2022-11-07 15:31 ` JunDong Song
2022-11-10 21:32 ` [PATCH 1/2] " Bjorn Helgaas
1 sibling, 0 replies; 3+ messages in thread
From: JunDong Song @ 2022-11-07 15:31 UTC (permalink / raw)
To: jingoohan1, gustavo.pimentel, lpieralisi
Cc: robh, kw, bhelgaas, linux-pci, linux-kernel, JunDong Song
of_pci_get_max_link_speed() may return a negative value,
causing the controller to not set the speed correctly.
Add a warning in case the driver engineer misses it.
Signed-off-by: JunDong Song <jundongsong1@gmail.com>
---
When I use the pcie dwc driver, the controller speed is abnormal,
but it has not been detected because of the @max-link-speed error,
so I think I need to return an error or warning here.
Thanks.
drivers/pci/controller/dwc/pcie-designware-host.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 39f3b37d4..0103b9a63 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -429,8 +429,11 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp)
pp->io_base = pci_pio_to_address(win->res->start);
}
- if (pci->link_gen < 1)
+ if (pci->link_gen < 1) {
pci->link_gen = of_pci_get_max_link_speed(np);
+ if (unlikely(pci->link_gen < 0))
+ dev_warn(dev, "Failed to get max link speed\n");
+ }
/* Set default bus ops */
bridge->ops = &dw_pcie_ops;
--
2.25.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH 1/2] PCI: dwc-host: Add a warning to prevent invalid values
2022-11-07 15:31 [PATCH 1/2] PCI: dwc-host: Add a warning to prevent invalid values JunDong Song
2022-11-07 15:31 ` [PATCH 2/2] " JunDong Song
@ 2022-11-10 21:32 ` Bjorn Helgaas
1 sibling, 0 replies; 3+ messages in thread
From: Bjorn Helgaas @ 2022-11-10 21:32 UTC (permalink / raw)
To: JunDong Song
Cc: jingoohan1, gustavo.pimentel, lpieralisi, robh, kw, bhelgaas,
linux-pci, linux-kernel
The subject lines are not quite accurate. The warning does nothing to
*prevent* invalid values; it only warns about them.
And it should say what *kind* of values we're talking about.
Maybe:
PCI: dwc: Warn about invalid 'max-link-speed' from DT
On Mon, Nov 07, 2022 at 11:31:07PM +0800, JunDong Song wrote:
> of_pci_get_max_link_speed() may return a negative value,
> causing the controller to not set the speed correctly.
> Add a warning in case the driver engineer misses it.
Rewrap this to fill 75 columns.
I would probably squash these into a single patch since they're
doing exactly the same thing to the host and endpoint cases.
> Signed-off-by: JunDong Song <jundongsong1@gmail.com>
> ---
>
> When I use the pcie dwc driver, the controller speed is abnormal,
> but it has not been detected because of the @max-link-speed error,
> so I think I need to return an error or warning here.
>
> Thanks.
>
> drivers/pci/controller/dwc/pcie-designware-ep.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> index 83ddb1902..573342601 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> @@ -739,8 +739,11 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> return -ENOMEM;
> ep->outbound_addr = addr;
>
> - if (pci->link_gen < 1)
> + if (pci->link_gen < 1) {
> pci->link_gen = of_pci_get_max_link_speed(np);
> + if (unlikely(pci->link_gen < 0))
Using "unlikely" here is unnecessary since this is not a performance
path, and it's a distraction.
> + dev_warn(dev, "Failed to get max link speed\n");
> + }
>
> epc = devm_pci_epc_create(dev, &epc_ops);
> if (IS_ERR(epc)) {
> --
> 2.25.1
>
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2022-11-10 21:32 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-11-07 15:31 [PATCH 1/2] PCI: dwc-host: Add a warning to prevent invalid values JunDong Song
2022-11-07 15:31 ` [PATCH 2/2] " JunDong Song
2022-11-10 21:32 ` [PATCH 1/2] " Bjorn Helgaas
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).