Re: [PATCH] PCI: qcom: Implement shutdown() callback
From: Krishna Chaitanya Chundru
Date: Wed Apr 02 2025 - 23:56:32 EST
On 4/2/2025 6:14 PM, Niklas Cassel wrote:
Hello Krishna,
On Tue, Apr 01, 2025 at 04:51:37PM +0530, Krishna Chaitanya Chundru wrote:
From: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
PCIe host controller drivers are supposed to properly remove the
endpoint drivers and release the resources during host shutdown/reboot
to avoid issues like smmu errors, NOC errors, etc.
So, stop and remove the root bus and its associated devices and release
its resources during system shutdown to ensure a clean shutdown/reboot.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@xxxxxxxxxxxxxxxx>
---
drivers/pci/controller/dwc/pcie-qcom.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index e4d3366ead1f9198693e6f9da4ae1dc40a3a0519..926811a0e63eb3663c1f41dc598659993546d832 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -1754,6 +1754,16 @@ static int qcom_pcie_probe(struct platform_device *pdev)
return ret;
}
+static void qcom_pcie_shutdown(struct platform_device *pdev)
+{
+ struct qcom_pcie *pcie = platform_get_drvdata(pdev);
+
+ dw_pcie_host_deinit(&pcie->pci->pp);
+ phy_exit(pcie->phy);
+ pm_runtime_put(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+}
+
static int qcom_pcie_suspend_noirq(struct device *dev)
{
struct qcom_pcie *pcie = dev_get_drvdata(dev);
@@ -1890,5 +1900,6 @@ static struct platform_driver qcom_pcie_driver = {
.pm = &qcom_pcie_pm_ops,
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
+ .shutdown = qcom_pcie_shutdown,
};
builtin_platform_driver(qcom_pcie_driver);
---
Out of curiosity, I tried something similar to on pcie-dw-rockchip.c
Simply having a ->shutdown() callback that only calls dw_pcie_host_deinit()
was enough for me to produce:
[ 40.209887] r8169 0004:41:00.0 eth0: Link is Down
[ 40.216572] ------------[ cut here ]------------
[ 40.216986] called from state HALTED
[ 40.217317] WARNING: CPU: 7 PID: 265 at drivers/net/phy/phy.c:1630 phy_stop+0x134/0x1a0
[ 40.218024] Modules linked in: rk805_pwrkey hantro_vpu v4l2_jpeg v4l2_vp9 v4l2_h264 v4l2_mem2mem videobuf2_v4l2 videobuf2_dma_contig videobuf2_memops videobuf2_common vidf
[ 40.220267] CPU: 7 UID: 0 PID: 265 Comm: init Not tainted 6.14.0+ #134 PREEMPT
[ 40.220908] Hardware name: Radxa ROCK 5B (DT)
[ 40.221289] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 40.221899] pc : phy_stop+0x134/0x1a0
[ 40.222222] lr : phy_stop+0x134/0x1a0
[ 40.222546] sp : ffff800082213820
[ 40.222836] x29: ffff800082213820 x28: ffff45ec84b30000 x27: 0000000000000000
[ 40.223463] x26: 0000000000000000 x25: 0000000000000000 x24: ffffbe8df7fde030
[ 40.224088] x23: ffff800082213990 x22: 0000000000000001 x21: ffff45ec80e10000
[ 40.224714] x20: ffff45ec82cb40c8 x19: ffff45ec82ccc000 x18: 0000000000000006
[ 40.225340] x17: 000000040044ffff x16: 005000f2b5503510 x15: 0720072007200720
[ 40.225966] x14: 0720072007200720 x13: 0720072007200720 x12: 0720072007200720
[ 40.226592] x11: 0000000000000058 x10: 0000000000000018 x9 : ffffbe8df556469c
[ 40.227217] x8 : 0000000000000268 x7 : ffffbe8df7a48648 x6 : ffffbe8df7a48648
[ 40.227842] x5 : 0000000000017fe8 x4 : 0000000000000000 x3 : 0000000000000000
[ 40.228468] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff45ec84b30000
[ 40.229093] Call trace:
[ 40.229308] phy_stop+0x134/0x1a0 (P)
[ 40.229634] rtl8169_down+0x34/0x280
[ 40.229952] rtl8169_close+0x64/0x100
[ 40.230275] __dev_close_many+0xbc/0x1f0
[ 40.230621] dev_close_many+0x94/0x160
[ 40.230951] unregister_netdevice_many_notify+0x14c/0x9c0
[ 40.231426] unregister_netdevice_queue+0xe4/0x100
[ 40.231848] unregister_netdev+0x2c/0x60
[ 40.232193] rtl_remove_one+0xa0/0xe0
[ 40.232517] pci_device_remove+0x4c/0xf8
[ 40.232864] device_remove+0x54/0x90
[ 40.233182] device_release_driver_internal+0x1d4/0x238
[ 40.233643] device_release_driver+0x20/0x38
[ 40.234019] pci_stop_bus_device+0x84/0xe0
[ 40.234381] pci_stop_bus_device+0x40/0xe0
[ 40.234741] pci_stop_root_bus+0x48/0x80
[ 40.235087] dw_pcie_host_deinit+0x34/0xe0
[ 40.235452] rockchip_pcie_shutdown+0x24/0x48
[ 40.235839] platform_shutdown+0x2c/0x48
[ 40.236187] device_shutdown+0x150/0x278
[ 40.236533] kernel_restart+0x4c/0xb8
[ 40.236859] __do_sys_reboot+0x178/0x280
[ 40.237206] __arm64_sys_reboot+0x2c/0x40
[ 40.237561] invoke_syscall+0x50/0x120
[ 40.237891] el0_svc_common.constprop.0+0x48/0xf0
[ 40.238305] do_el0_svc+0x24/0x38
[ 40.238597] el0_svc+0x30/0xd0
[ 40.238868] el0t_64_sync_handler+0x10c/0x138
[ 40.239251] el0t_64_sync+0x198/0x1a0
[ 40.239575] ---[ end trace 0000000000000000 ]---
Hi Niklas,
The issue which you are seeing with specific to the RealTek ethernet
driver and should be fixed by RealTek driver nothing to do with the host
controller.
Did you try your change with a simple network card connected to the PCI slot?
(And not just another qcom board running in EP mode.)
we don't have ethernet card's to try we tried with qcom PCIe switch
which usb hub connected as a endpoint.
- Krishna Chaitanya.
I don't see why you wouldn't see the same thing as me.
Kind regards,
Niklas