RE: Regression since 6.1.46 (commit 8ee39ec): rtsx_pci from drivers/misc/cardreader breaks NVME power state, preventing system boot

[Ricky WU <ricky_wu@realtek.com>]

Hi Paul,

We have notice this issue....
https://lore.kernel.org/lkml/fa82d9dcbe83403abc644c20922b47f9@realtek.com/t/#m90373a16017f07ca32f43d6b4327164fb31bf9bb
main reason is:
"it is a system power saving issue....
In the past if the BIOS(config space) not set L1-substate our driver will keep drive low CLKREQ# when HOST want to enter power saving state that make whole system not enter the power saving state.
But this patch we release the CLKREQ# to HOST, make whole system can enter power saving state success when the HOST want to enter the power saving state, but I don't  know why this system can not wake out success from power saving state"

This is a PCIE CLKREQ# design problem on those platform, the pcie spec allow device release the CLKREQ# to HOST, this patch only do this....

We are thinking about how to compatible with these potentially problematic platforms

Ricky
> -----Original Message-----
> From: Paul Grandperrin <paul.grandperrin@gmail.com>
> Sent: Tuesday, September 12, 2023 8:29 PM
> To: stable@vger.kernel.org
> Cc: regressions@lists.linux.dev; Wei_wang <wei_wang@realsil.com.cn>; Roger
> Tseng <rogerable@realtek.com>; Ricky WU <ricky_wu@realtek.com>
> Subject: Regression since 6.1.46 (commit 8ee39ec): rtsx_pci from
> drivers/misc/cardreader breaks NVME power state, preventing system boot
> 
> 
> External mail.
> 
> 
> 
> Hi kernel maintainers!
> 
> My computer doesn't boot with kernels newer than 6.1.45.
> 
> Here's what happens:
> - system boots in initramfs
> - detects my encrypted ZFS pool and asks for password
> - mount system, pivots to it, starts real init
> - before any daemon had time to start, the system hangs and the kernel
> writes on the console
> "nvme 0000:04:00.0: Unable to change power state from D3cold to D0,
> device inaccessible"
> - if I reboot directly without powering off (using magic sysrq or
> panic=10), even the UEFI complains about not finding any storage to
> boot from.
> - after a real power off, I can boot using a kernel <= 6.1.45.
> 
> The bug has been discussed here:
> https://bugzilla.kernel.org/show_bug.cgi?id=217705
> 
> My laptop is a Dell XPS 15 9560 (Intel 7700hq).
> 
> I bisected between 6.1.45 and 6.1.46 and found this commit
> 
> commit 8ee39ec479147e29af704639f8e55fce246ed2d9
> Author: Ricky WU <ricky_wu@realtek.com>
> Date:   Tue Jul 25 09:10:54 2023 +0000
> 
>     misc: rtsx: judge ASPM Mode to set PETXCFG Reg
> 
>     commit 101bd907b4244a726980ee67f95ed9cafab6ff7a upstream.
> 
>     ASPM Mode is ASPM_MODE_CFG need to judge the value of clkreq_0
>     to set HIGH or LOW, if the ASPM Mode is ASPM_MODE_REG
>     always set to HIGH during the initialization.
> 
>     Cc: stable@vger.kernel.org
>     Signed-off-by: Ricky Wu <ricky_wu@realtek.com>
>     Link:
> https://lore.kernel.org/r/52906c6836374c8cb068225954c5543a@realtek.com
>     Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> 
>  drivers/misc/cardreader/rts5227.c  |  2 +-
>  drivers/misc/cardreader/rts5228.c  | 18 ------------------
>  drivers/misc/cardreader/rts5249.c  |  3 +--
>  drivers/misc/cardreader/rts5260.c  | 18 ------------------
>  drivers/misc/cardreader/rts5261.c  | 18 ------------------
>  drivers/misc/cardreader/rtsx_pcr.c |  5 ++++-
>  6 files changed, 6 insertions(+), 58 deletions(-)
> 
> If I build 6.1.51 with this commit reverted, my laptop works again,
> confirming that this commit is to blame.
> 
> Also, blacklisting `rtsx_pci_sdmmc` and `rtsx_pci`, while preventing to
> use the sd card reading, allows to boot the system.
> 
> I can't try 6.4 or 6.5 because my system is dependent on ZFS..
> 
> Have a nice day,
> Paul Grandperrin
>