Re: [PATCH rtw-next 2/2] wifi: rtw88: usb: Upload the firmware in bigger chunks

[Bitterblue Smith <rtl8821cerfe2@gmail.com>]

On 08/05/2025 06:29, Ping-Ke Shih wrote:
> : Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
>> RTL8811AU stops responding during the firmware download on some systems:
>>
>> [  809.256440] rtw_8821au 5-2.1:1.0: Firmware version 42.4.0, H2C version 0
>> [  812.759142] rtw_8821au 5-2.1:1.0 wlp48s0f4u2u1: renamed from wlan0
>> [  837.315388] rtw_8821au 1-4:1.0: write register 0x1ef4 failed with -110
>> [  867.524259] rtw_8821au 1-4:1.0: write register 0x1ef8 failed with -110
>> [  868.930976] rtw_8821au 5-2.1:1.0 wlp48s0f4u2u1: entered promiscuous mode
>> [  897.730952] rtw_8821au 1-4:1.0: write register 0x1efc failed with -110
>>
>> Maybe it takes too long when writing the firmware 4 bytes at a time.
>>
>> Write 196 bytes at a time for RTL8821AU, RTL8811AU, and RTL8812AU,
>> and 254 bytes at a time for RTL8723DU. These are the sizes used in
>> their official drivers. Tested with all these chips.
>>
>> Cc: stable@vger.kernel.org
>> Link: https://github.com/lwfinger/rtw88/issues/344
>> Signed-off-by: Bitterblue Smith <rtl8821cerfe2@gmail.com>
> 
> Acked-by: Ping-Ke Shih <pkshih@realtek.com>
> 
> [..]
> 
>> diff --git a/drivers/net/wireless/realtek/rtw88/usb.c b/drivers/net/wireless/realtek/rtw88/usb.c
>> index b16db579fdce..ad15ce12ab7f 100644
>> --- a/drivers/net/wireless/realtek/rtw88/usb.c
>> +++ b/drivers/net/wireless/realtek/rtw88/usb.c
>> @@ -165,6 +165,60 @@ static void rtw_usb_write32(struct rtw_dev *rtwdev, u32 addr, u32 val)
>>         rtw_usb_write(rtwdev, addr, val, 4);
>>  }
>>
>> +static void rtw_usb_write_firmware_page(struct rtw_dev *rtwdev, u32 page,
>> +                                       const u8 *data, u32 size)
>> +{
>> +       struct rtw_usb *rtwusb = rtw_get_usb_priv(rtwdev);
>> +       struct usb_device *udev = rtwusb->udev;
>> +       u32 addr = FW_8192C_START_ADDRESS;
> 
> FW_8192C_START_ADDRESS is existing already. But something like
> RTW_USB_FW_START_ADDRESS would be better. 
> 

I agree, because rtw88 doesn't handle RTL8192C. There is
FW_START_ADDR_LEGACY in fw.h. I must not have noticed it before.
Should I send v2 for this?

>> +       u8 *data_dup, *buf;
>> +       u32 n, block_size;
>> +       int ret;
>> +
>> +       switch (rtwdev->chip->id) {
>> +       case RTW_CHIP_TYPE_8723D:
>> +               block_size = 254;
>> +               break;
>> +       default:
>> +               block_size = 196;
>> +               break;
>> +       }
>> +
>> +       data_dup = kmemdup(data, size, GFP_KERNEL);
> 
> This is because type of argument `data` of usb_control_msg() is not const, right?
> Do you know if usb_control_msg() will actually modify the data?
> 

No, it's because usb_control_msg() rejects memory allocated by
vmalloc(). I don't remember what error it printed. Maybe because the
memory is not suitable for DMA.