Re: [PATCH V2] net: ethernet: ti: cpsw_new: enable mac_managed_pm to fix mdio

[Paolo Abeni <pabeni@redhat.com>]

On Mon, 2024-01-22 at 15:03 +0530, Sinthu Raja wrote:
> From: Sinthu Raja <sinthu.raja@ti.com>

Please respect the 24h grace period before posting a new version:

https://elixir.bootlin.com/linux/latest/source/Documentation/process/maintainer-netdev.rst#L399

Also please keep a consistent revision numbering scheme. This v2
apparently come after v3 ?!?

> The below commit  introduced a WARN when phy state is not in the states:
> PHY_HALTED, PHY_READY and PHY_UP.
> commit 744d23c71af3 ("net: phy: Warn about incorrect mdio_bus_phy_resume() state")
> 
> When cpsw_new resumes, there have port in PHY_NOLINK state, so the below
> warning comes out. Set mac_managed_pm be true to tell mdio that the phy
> resume/suspend is managed by the mac, to fix the following warning:
> 
> WARNING: CPU: 0 PID: 965 at drivers/net/phy/phy_device.c:326 mdio_bus_phy_resume+0x140/0x144
> CPU: 0 PID: 965 Comm: sh Tainted: G           O       6.1.46-g247b2535b2 #1
> Hardware name: Generic AM33XX (Flattened Device Tree)
>  unwind_backtrace from show_stack+0x18/0x1c
>  show_stack from dump_stack_lvl+0x24/0x2c
>  dump_stack_lvl from __warn+0x84/0x15c
>  __warn from warn_slowpath_fmt+0x1a8/0x1c8
>  warn_slowpath_fmt from mdio_bus_phy_resume+0x140/0x144
>  mdio_bus_phy_resume from dpm_run_callback+0x3c/0x140
>  dpm_run_callback from device_resume+0xb8/0x2b8
>  device_resume from dpm_resume+0x144/0x314
>  dpm_resume from dpm_resume_end+0x14/0x20
>  dpm_resume_end from suspend_devices_and_enter+0xd0/0x924
>  suspend_devices_and_enter from pm_suspend+0x2e0/0x33c
>  pm_suspend from state_store+0x74/0xd0
>  state_store from kernfs_fop_write_iter+0x104/0x1ec
>  kernfs_fop_write_iter from vfs_write+0x1b8/0x358
>  vfs_write from ksys_write+0x78/0xf8
>  ksys_write from ret_fast_syscall+0x0/0x54
> Exception stack(0xe094dfa8 to 0xe094dff0)
> dfa0:                   00000004 005c3fb8 00000001 005c3fb8 00000004 00000001
> dfc0: 00000004 005c3fb8 b6f6bba0 00000004 00000004 0059edb8 00000000 00000000
> dfe0: 00000004 bed918f0 b6f09bd3 b6e89a66
> 
> Fixes: 744d23c71af3 ("net: phy: Warn about incorrect mdio_bus_phy_resume() state")

I think the real issue was introduced somewhere else in the TI driver.
The above commit just report the inconsistent state.

Note that you probably will a small series of 2 separate patches to
address the issue bot in cpsw_new.c and cpsw.c, as mentioned by Roger.

Cheers,

Paolo