Hi Sergio,
On 12/3/20 7:00 pm, Sergio Paracuellos wrote:
Some time ago Greg Ungerer reported some random hangs using
the staging mt7621-pci driver:
See:
* http://driverdev.linuxdriverproject.org/pipermail/driverdev-devel/2019-June/134947.html
Try to fix that is the main motivation of this patch series.
Also in openwrt there is a driver for mt7621-pci which seems was rewritten
from scratch (for kernel 4.14) by Ryder Lee and Weijie Gao from mediatek.
There the approach for reset assert-deassert process is to set as 'gpio'
the function for all the 'pcie' group for the pinctrl driver and use those
gpio's as a reset for the end points. The driver I am talking about is still
using legacy pci and legacy gpio kernel interfaces. IMHO, the correct thing
to do is make this staging driver properly clean and functional and put it
in its correct place in the mainline.
See:
* https://gist.github.com/dengqf6/7a9e9b4032d99f1a91dd9256c8a65c36
Because of all of this this patch series tries to avoid random hangs of boot
trying to use the 'reset-gpios' approach.
Changes are being tested by openwrt people and seems to work.
Thanks for the updated patch.
I applied the patches to the staging git tree for testing.
I have seen a couple of different problems on boot up:
...
rt2880-pinmux pinctrl: pcie is already enabled
mt7621-pci 1e140000.pcie: Error applying setting, reverse things back
mt7621-pci 1e140000.pcie: Failed to get GPIO for PCIe1
mt7621-pci 1e140000.pcie: Failed to get GPIO for PCIe2
gpiod_set_value: invalid GPIO (errorpointer)
gpiod_set_value: invalid GPIO (errorpointer)
mt7621-pci-phy 1e149000.pcie-phy: Xtal is 40MHz
mt7621-pci-phy 1e149000.pcie-phy: Xtal is 40MHz
mt7621-pci-phy 1e14a000.pcie-phy: Xtal is 40MHz
gpiod_set_value: invalid GPIO (errorpointer)
gpiod_set_value: invalid GPIO (errorpointer)
mt7621-pci 1e140000.pcie: pcie1 no card, disable it (RST & CLK)
mt7621-pci 1e140000.pcie: pcie2 no card, disable it (RST & CLK)
mt7621-pci 1e140000.pcie: PCIE0 enabled
mt7621-pci 1e140000.pcie: PCI coherence region base: 0x60000000, mask/settings: 0xf0000002
mt7621-pci 1e140000.pcie: PCI host bridge to bus 0000:00
pci_bus 0000:00: root bus resource [io 0xffffffff]
pci_bus 0000:00: root bus resource [mem 0x60000000-0x6fffffff]
pci_bus 0000:00: root bus resource [bus 00-ff]
pci 0000:00:00.0: [0e8d:0801] type 01 class 0x060400
pci 0000:00:00.0: reg 0x10: [mem 0x00000000-0x7fffffff]
pci 0000:00:00.0: reg 0x14: [mem 0x00000000-0x0000ffff]
pci 0000:00:00.0: supports D1
pci 0000:00:00.0: PME# supported from D0 D1 D3hot
pci 0000:00:00.0: bridge configuration invalid ([bus 00-00]), reconfiguring
pci 0000:01:00.0: [168c:003c] type 00 class 0x028000
pci 0000:01:00.0: reg 0x10: [mem 0x00000000-0x001fffff 64bit]
pci 0000:01:00.0: reg 0x30: [mem 0x00000000-0x0000ffff pref]
pci 0000:01:00.0: supports D1 D2
pci 0000:00:00.0: PCI bridge to [bus 01-ff]
pci 0000:00:00.0: bridge window [io 0x0000-0x0fff]
pci 0000:00:00.0: bridge window [mem 0x00000000-0x000fffff]
pci 0000:00:00.0: bridge window [mem 0x00000000-0x000fffff pref]
pci_bus 0000:01: busn_res: [bus 01-ff] end is updated to 01
pci 0000:00:00.0: BAR 0: no space for [mem size 0x80000000]
pci 0000:00:00.0: BAR 0: failed to assign [mem size 0x80000000]
pci 0000:00:00.0: BAR 8: assigned [mem 0x60000000-0x601fffff]
pci 0000:00:00.0: BAR 9: assigned [mem 0x60200000-0x602fffff pref]
pci 0000:00:00.0: BAR 1: assigned [mem 0x60300000-0x6030ffff]
pci 0000:00:00.0: BAR 7: no space for [io size 0x1000]
pci 0000:00:00.0: BAR 7: failed to assign [io size 0x1000]
pci 0000:01:00.0: BAR 0: assigned [mem 0x60000000-0x601fffff 64bit]
pci 0000:01:00.0: BAR 6: assigned [mem 0x60200000-0x6020ffff pref]
pci 0000:00:00.0: PCI bridge to [bus 01]
pci 0000:00:00.0: bridge window [mem 0x60000000-0x601fffff]
pci 0000:00:00.0: bridge window [mem 0x60200000-0x602fffff pref]
pcieport 0000:00:00.0: of_irq_parse_pci: failed with rc=-22
pcieport 0000:00:00.0: enabling device (0004 -> 0006)
CPU 2 Unable to handle kernel paging request at virtual address fffffff0, epc == 8039c7b0, ra == 804fe128
Oops[#1]:
CPU: 2 PID: 107 Comm: kworker/2:1 Not tainted 5.6.0-rc3-00180-gc15e7f072288-dirty #2
Workqueue: events deferred_probe_work_func
$ 0 : 00000000 00000001 820d6984 00000001
$ 4 : fffffff0 00000001 00000000 803a0000
$ 8 : 00000024 ffffffff 00000001 302e3030
$12 : 00000000 8e26fbd8 ffffffff 00000020
$16 : 820d6980 820e0250 00000000 8e26fcd0
$20 : 820e01e0 809a0000 820e0228 8fd47e10
$24 : 00000000 00000020
$28 : 8e26e000 8e26fc70 8e26fcf8 804fe128
Hi : 00000125
Lo : 122f2000
epc : 8039c7b0 gpiod_free+0x14/0x6c
ra : 804fe128 mt7621_pci_probe+0x700/0xcd8
Status: 1100fc03 KERNEL EXL IE
Cause : 00800008 (ExcCode 02)
BadVA : fffffff0
PrId : 0001992f (MIPS 1004Kc)
Modules linked in:
Process kworker/2:1 (pid: 107, threadinfo=(ptrval), task=(ptrval), tls=00000000)
Stack : 820e0250 809e2aa0 820d6380 820e0250 820d6980 804fe128 1e160000 00000001
60000000 00000000 f0000002 00000000 00000000 809a0000 8fd47e10 808d63d4
80930000 808d6260 808d0000 808d61fc 808c0000 8fd47e10 808d6208 808d0000
8e26fcd0 8e26fcd0 809e2aa0 809db510 809db510 00000006 00000001 00000000
00000000 00000000 01000000 1e1440ff 00000000 00000000 1e160000 00000000
...
Call Trace:
[<8039c7b0>] gpiod_free+0x14/0x6c
[<804fe128>] mt7621_pci_probe+0x700/0xcd8
[<80402ab8>] platform_drv_probe+0x40/0x94
[<80400a74>] really_probe+0x104/0x364
[<803feb74>] bus_for_each_drv+0x84/0xdc
[<80400924>] __device_attach+0xdc/0x120
[<803ffb5c>] bus_probe_device+0xa0/0xbc
[<80400124>] deferred_probe_work_func+0x7c/0xbc
[<800420e8>] process_one_work+0x230/0x450
[<80042638>] worker_thread+0x330/0x5fc
[<80048eb0>] kthread+0x12c/0x134
[<80007438>] ret_from_kernel_thread+0x14/0x1c
Code: 27bdffe8 afb00010 afbf0014 <8c830000> 10600005 00808025 0c0e6efb 00000000 14400007
---[ end trace d9831fec9efd296d ]---
And on another boot:
...
rt2880-pinmux pinctrl: pcie is already enabled
mt7621-pci 1e140000.pcie: Error applying setting, reverse things back
mt7621-pci 1e140000.pcie: Failed to get GPIO for PCIe1
mt7621-pci 1e140000.pcie: Failed to get GPIO for PCIe2
gpiod_set_value: invalid GPIO (errorpointer)
gpiod_set_value: invalid GPIO (errorpointer)
mt7621-pci-phy 1e149000.pcie-phy: Xtal is 40MHz
mt7621-pci-phy 1e149000.pcie-phy: Xtal is 40MHz
mt7621-pci-phy 1e14a000.pcie-phy: Xtal is 40MHz
gpiod_set_value: invalid GPIO (errorpointer)
gpiod_set_value: invalid GPIO (errorpointer)
mt7621-pci 1e140000.pcie: pcie0 no card, disable it (RST & CLK)
mt7621-pci 1e140000.pcie: pcie1 no card, disable it (RST & CLK)
mt7621-pci 1e140000.pcie: pcie2 no card, disable it (RST & CLK)
mt7621-pci 1e140000.pcie: Nothing is connected in virtual bridges. Exiting...
CPU 1 Unable to handle kernel paging request at virtual address fffffff0, epc == 8039c7b0, ra == 804fe128
Oops[#1]:
CPU: 1 PID: 103 Comm: kworker/1:1 Not tainted 5.6.0-rc3-00180-gc15e7f072288-dirty #2
Workqueue: events deferred_probe_work_func
$ 0 : 00000000 00000001 82051e84 00000001
$ 4 : fffffff0 00000001 00000000 803a0000
$ 8 : 2e000000 80940000 00000018 000000d6
$12 : 6976206e 00000000 00000000 61757472
$16 : 82051e80 820d4250 00000000 8fd6dcd0
$20 : 820d41e0 820d424c 00000000 809a0000
$24 : 00000008 803ef8f4
$28 : 8fd6c000 8fd6dc70 808d6280 804fe128
Hi : 00000125
Lo : 122f2000
epc : 8039c7b0 gpiod_free+0x14/0x6c
ra : 804fe128 mt7621_pci_probe+0x700/0xcd8
Status: 1100fc03 KERNEL EXL IE
Cause : 00800008 (ExcCode 02)
BadVA : fffffff0
PrId : 0001992f (MIPS 1004Kc)
Modules linked in:
Process kworker/1:1 (pid: 103, threadinfo=(ptrval), task=(ptrval), tls=00000000)
Stack : 8fd6dc90 808d62a8 82051880 820d4250 82051e80 804fe128 809d0000 00000001
00000001 00000001 00000000 00000001 00000000 8fd47e10 8fd47e10 808d63d4
80930000 808d6260 808d0000 808d61fc 808c0000 8fd47e10 808d6208 808d0000
8fd6dcd0 8fd6dcd0 1e140000 1e1400ff 809e2af8 00000200 00000000 00000000
00000000 00000000 1e144000 1e1440ff 809e2af8 00000200 00000000 00000000
...
Call Trace:
[<8039c7b0>] gpiod_free+0x14/0x6c
[<804fe128>] mt7621_pci_probe+0x700/0xcd8
[<80402ab8>] platform_drv_probe+0x40/0x94
[<80400a74>] really_probe+0x104/0x364
[<803feb74>] bus_for_each_drv+0x84/0xdc
[<80400924>] __device_attach+0xdc/0x120
[<803ffb5c>] bus_probe_device+0xa0/0xbc
[<80400124>] deferred_probe_work_func+0x7c/0xbc
[<800420e8>] process_one_work+0x230/0x450
[<80042638>] worker_thread+0x330/0x5fc
[<80048eb0>] kthread+0x12c/0x134
[<80007438>] ret_from_kernel_thread+0x14/0x1c
Code: 27bdffe8 afb00010 afbf0014 <8c830000> 10600005 00808025 0c0e6efb 00000000 14400007
---[ end trace 5affc5903364c81f ]---
Regards
Greg
Hope this helps.
Changes in v3:
* Avoid to fail if gpio descriptor fails on get.
* re-do PATCH 1 commit message.
* Take into account gpio low polarity on request and assert and deassert.
* Review error path of driver to properly release gpio's resources.
Changes in v2:
* restore configuration for pers mode to GPIO.
* Avoid to read FTS_NUM register in reset state.
* Release gpio's patch added
Best regards,
Sergio Paracuellos
Sergio Paracuellos (5):
staging: mt7621-pci: use gpios for properly reset
staging: mt7621-pci: change value for 'PERST_DELAY_US'
staging: mt7621-dts: make use of 'reset-gpios' property for pci
staging: mt7621-pci: bindings: update doc accordly to last changes
staging: mt7621-pci: release gpios after pci initialization
drivers/staging/mt7621-dts/mt7621.dtsi | 11 +-
.../mt7621-pci/mediatek,mt7621-pci.txt | 7 +-
drivers/staging/mt7621-pci/pci-mt7621.c | 107 +++++++++++-------
3 files changed, 80 insertions(+), 45 deletions(-)
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