From: Krishna chaitanya chundru <quic_krichai@quicinc.com>
To: "Jingoo Han" <jingoohan1@gmail.com>,
"Gustavo Pimentel" <gustavo.pimentel@synopsys.com>,
"Manivannan Sadhasivam" <manivannan.sadhasivam@linaro.org>,
"Lorenzo Pieralisi" <lpieralisi@kernel.org>,
"Krzysztof Wilczyński" <kw@linux.com>,
"Rob Herring" <robh@kernel.org>,
"Bjorn Helgaas" <bhelgaas@google.com>
Cc: <linux-pci@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
<quic_vbadigan@quicinc.com>, <quic_ramkri@quicinc.com>,
<quic_nitegupt@quicinc.com>, <quic_skananth@quicinc.com>,
<quic_parass@quicinc.com>,
Krishna chaitanya chundru <quic_krichai@quicinc.com>
Subject: [PATCH v2] PCI: dwc: Enable runtime pm of the host bridge
Date: Tue, 5 Mar 2024 15:19:01 +0530 [thread overview]
Message-ID: <20240305-runtime_pm_enable-v2-1-a849b74091d1@quicinc.com> (raw)
The Controller driver is the parent device of the PCIe host bridge,
PCI-PCI bridge and PCIe endpoint as shown below.
PCIe controller(Top level parent & parent of host bridge)
|
v
PCIe Host bridge(Parent of PCI-PCI bridge)
|
v
PCI-PCI bridge(Parent of endpoint driver)
|
v
PCIe endpoint driver
Since runtime PM is disabled for host bridge, the state of the child
devices under the host bridge is not taken into account by PM framework
for the top level parent, PCIe controller. So PM framework, allows
the controller driver to enter runtime PM irrespective of the state
of the devices under the host bridge. And this causes the topology
breakage and also possible PM issues.
So enable pm runtime for the host bridge, so that controller driver
goes to suspend only when all child devices goes to runtime suspend.
Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
---
Changes in v2:
- Updated commit message as suggested by mani.
- Link to v1: https://lore.kernel.org/r/20240219-runtime_pm_enable-v1-1-d39660310504@quicinc.com
---
drivers/pci/controller/dwc/pcie-designware-host.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index d5fc31f8345f..57756a73df30 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -16,6 +16,7 @@
#include <linux/of_pci.h>
#include <linux/pci_regs.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include "../../pci.h"
#include "pcie-designware.h"
@@ -505,6 +506,9 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp)
if (pp->ops->post_init)
pp->ops->post_init(pp);
+ pm_runtime_set_active(&bridge->dev);
+ pm_runtime_enable(&bridge->dev);
+
return 0;
err_stop_link:
---
base-commit: 6613476e225e090cc9aad49be7fa504e290dd33d
change-id: 20240219-runtime_pm_enable-bdc17914bd50
Best regards,
--
Krishna chaitanya chundru <quic_krichai@quicinc.com>
next reply other threads:[~2024-03-05 9:49 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-05 9:49 Krishna chaitanya chundru [this message]
2024-03-05 19:57 ` [PATCH v2] PCI: dwc: Enable runtime pm of the host bridge Bjorn Helgaas
2024-03-07 1:58 ` Krishna Chaitanya Chundru
2024-03-07 21:55 ` Bjorn Helgaas
2024-03-08 3:08 ` Krishna Chaitanya Chundru
2024-03-08 17:12 ` Bjorn Helgaas
2024-03-19 11:11 ` Manivannan Sadhasivam
2024-03-20 15:27 ` Krishna Chaitanya Chundru
2024-03-22 22:04 ` Bjorn Helgaas
2024-03-25 11:09 ` Manivannan Sadhasivam
2024-04-12 10:32 ` Krishna Chaitanya Chundru
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20240305-runtime_pm_enable-v2-1-a849b74091d1@quicinc.com \
--to=quic_krichai@quicinc.com \
--cc=bhelgaas@google.com \
--cc=gustavo.pimentel@synopsys.com \
--cc=jingoohan1@gmail.com \
--cc=kw@linux.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=lpieralisi@kernel.org \
--cc=manivannan.sadhasivam@linaro.org \
--cc=quic_nitegupt@quicinc.com \
--cc=quic_parass@quicinc.com \
--cc=quic_ramkri@quicinc.com \
--cc=quic_skananth@quicinc.com \
--cc=quic_vbadigan@quicinc.com \
--cc=robh@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.