Re: [PATCH rtw-next] wifi: rtw88: sdio: use indirect IO for device registers before power-on

[Andrey Skvortsov <andrej.skvortzov@gmail.com>]

Hi,

This patch was recently backported to stable kernels (v6.12.58) and it broke
wlan on PinePhone, that uses 8723cs SDIO chip. The same problem
appears of course on latest 6.18-rc6. Reverting this change resolves
the problem.

```
$ sudo dmesg | grep -i rtw88
[   24.940551] rtw88_8723cs mmc1:0001:1: WOW Firmware version 11.0.0, H2C version 0
[   24.953085] rtw88_8723cs mmc1:0001:1: Firmware version 11.0.0, H2C version 0
[   24.955892] rtw88_8723cs mmc1:0001:1: sdio read32 failed (0xf0): -110
[   24.973135] rtw88_8723cs mmc1:0001:1: sdio write8 failed (0x1c): -110
[   24.980673] rtw88_8723cs mmc1:0001:1: sdio read32 failed (0xf0): -110
...
[   25.446691] rtw88_8723cs mmc1:0001:1: sdio read8 failed (0x100): -110
[   25.453569] rtw88_8723cs mmc1:0001:1: mac power on failed
[   25.459077] rtw88_8723cs mmc1:0001:1: failed to power on mac
[   25.464841] rtw88_8723cs mmc1:0001:1: failed to setup chip efuse info
[   25.464856] rtw88_8723cs mmc1:0001:1: failed to setup chip information
[   25.478341] rtw88_8723cs mmc1:0001:1: probe with driver rtw88_8723cs failed with error -114
```

On 25-07-24 08:48, Ping-Ke Shih wrote:
> The register REG_SYS_CFG1 is used to determine chip basic information
> as arguments of following flows, such as download firmware and load PHY
> parameters, so driver read the value early (before power-on).
> 
> However, the direct IO is disallowed before power-on, or it causes wrong
> values, which driver recognizes a chip as a wrong type RF_1T1R, but
> actually RF_2T2R, causing driver warns:
> 
>   rtw88_8822cs mmc1:0001:1: unsupported rf path (1)
> 
> Fix it by using indirect IO before power-on.
> 
> Reported-by: Piotr Oniszczuk <piotr.oniszczuk@gmail.com>
> Closes: https://lore.kernel.org/linux-wireless/699C22B4-A3E3-4206-97D0-22AB3348EBF6@gmail.com/T/#t
> Suggested-by: Bitterblue Smith <rtl8821cerfe2@gmail.com>
> Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
> ---
>  drivers/net/wireless/realtek/rtw88/sdio.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/net/wireless/realtek/rtw88/sdio.c b/drivers/net/wireless/realtek/rtw88/sdio.c
> index cc2d4fef3587..99d7c629eac6 100644
> --- a/drivers/net/wireless/realtek/rtw88/sdio.c
> +++ b/drivers/net/wireless/realtek/rtw88/sdio.c
> @@ -144,6 +144,10 @@ static u32 rtw_sdio_to_io_address(struct rtw_dev *rtwdev, u32 addr,
>  
>  static bool rtw_sdio_use_direct_io(struct rtw_dev *rtwdev, u32 addr)
>  {
> +	if (!test_bit(RTW_FLAG_POWERON, rtwdev->flags) &&
> +	    !rtw_sdio_is_bus_addr(addr))
> +		return false;
> +
>  	return !rtw_sdio_is_sdio30_supported(rtwdev) ||
>  		rtw_sdio_is_bus_addr(addr);
>  }
> -- 
> 2.25.1
> 

-- 
Best regards,
Andrey Skvortsov