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Date:   Tue, 24 Sep 2019 17:32:25 +0800
From:   Wen Gong <wgong@codeaurora.org>
To:     Kalle Valo <kvalo@codeaurora.org>
Cc:     ath10k@lists.infradead.org, linux-wireless@vger.kernel.org
Subject: Re: [PATCH v5 3/8] ath10k: change max RX bundle size from 8 to 32 for
 sdio
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On 2019-09-23 17:05, Kalle Valo wrote:

>> 
>> +#define ATH10K_HTC_FLAG_BUNDLE_MASK 0xF0
>> +#define ATH10K_HTC_BUNDLE_EXTRA_MASK GENMASK(3, 2)
>> +
>> +#define ATH10K_HTC_GET_BUNDLE_COUNT(flags) \
>> +	    (FIELD_GET(ATH10K_HTC_FLAG_BUNDLE_MASK, (flags)) +  \
>> +	    (FIELD_GET(ATH10K_HTC_BUNDLE_EXTRA_MASK, (flags)) << 4))
> 
> When using FIELD_GET() there should be no need to use '<<', the main id
> of FIELD_GET() and BITMASK() is that there's no need do any manual
> shifting. So I suspect something is wrong here, but didn't have time to
> investigate.
the value is like this:
the u8 flags:
b7 b6 b5 b4 b3 b2 b1 b0
the count= 0Bb7b6b5b4 + 0Bb3b2 << 4
FIELD_GET is to >>, not <<
so it need to manual shift for the "0Bb3b2 << 4"