linux-kernel - Re: [PATCH] soc: qcom: Rework BCM_TCS

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Message-ID: <a4c44b88-d106-4365-b405-ced561b9e526@linaro.org>
Date: Fri, 25 Oct 2024 15:06:34 +0300
From: Eugen Hristev <eugen.hristev@...aro.org>
To: Konrad Dybcio <konrad.dybcio@....qualcomm.com>
Cc: andersson@...nel.org, konradybcio@...nel.org,
 linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org
Subject: Re: [PATCH] soc: qcom: Rework BCM_TCS_CMD macro



On 10/25/24 12:03, Konrad Dybcio wrote:
> On 25.10.2024 10:48 AM, Eugen Hristev wrote:
>> Reworked BCM_TCS_CMD macro in order to fix warnings from sparse:
>>
>> drivers/clk/qcom/clk-rpmh.c:270:28: warning: restricted __le32 degrades to integer
>> drivers/clk/qcom/clk-rpmh.c:270:28: warning: restricted __le32 degrades to integer
>>
>> While at it, used u32_encode_bits which made the code easier to
>> follow and removed unnecessary shift definitions.
>>
>> Signed-off-by: Eugen Hristev <eugen.hristev@...aro.org>
>> ---
>>   include/soc/qcom/tcs.h | 19 ++++++++-----------
>>   1 file changed, 8 insertions(+), 11 deletions(-)
>>
>> diff --git a/include/soc/qcom/tcs.h b/include/soc/qcom/tcs.h
>> index 3acca067c72b..130ed2582f37 100644
>> --- a/include/soc/qcom/tcs.h
>> +++ b/include/soc/qcom/tcs.h
>> @@ -60,22 +60,19 @@ struct tcs_request {
>>   	struct tcs_cmd *cmds;
>>   };
>>   
>> -#define BCM_TCS_CMD_COMMIT_SHFT		30
>>   #define BCM_TCS_CMD_COMMIT_MASK		0x40000000
>> -#define BCM_TCS_CMD_VALID_SHFT		29
>>   #define BCM_TCS_CMD_VALID_MASK		0x20000000
>> -#define BCM_TCS_CMD_VOTE_X_SHFT		14
>>   #define BCM_TCS_CMD_VOTE_MASK		0x3fff
>> -#define BCM_TCS_CMD_VOTE_Y_SHFT		0
>> -#define BCM_TCS_CMD_VOTE_Y_MASK		0xfffc000
>> +#define BCM_TCS_CMD_VOTE_Y_MASK		0x3fff
>> +#define BCM_TCS_CMD_VOTE_X_MASK		0xfffc000
>>   
>>   /* Construct a Bus Clock Manager (BCM) specific TCS command */
>>   #define BCM_TCS_CMD(commit, valid, vote_x, vote_y)		\
>> -	(((commit) << BCM_TCS_CMD_COMMIT_SHFT) |		\
>> -	((valid) << BCM_TCS_CMD_VALID_SHFT) |			\
>> -	((cpu_to_le32(vote_x) &					\
>> -	BCM_TCS_CMD_VOTE_MASK) << BCM_TCS_CMD_VOTE_X_SHFT) |	\
>> -	((cpu_to_le32(vote_y) &					\
>> -	BCM_TCS_CMD_VOTE_MASK) << BCM_TCS_CMD_VOTE_Y_SHFT))
>> +	(u32_encode_bits(commit, BCM_TCS_CMD_COMMIT_MASK) |	\
>> +	u32_encode_bits(valid, BCM_TCS_CMD_VALID_MASK) |	\
>> +	u32_encode_bits((__force u32)cpu_to_le32(vote_x),	\
>> +			BCM_TCS_CMD_VOTE_X_MASK) |		\
>> +	u32_encode_bits((__force u32)cpu_to_le32(vote_y),	\
>> +			BCM_TCS_CMD_VOTE_Y_MASK))
> 
> FIELD_PREP/GET?
> 
> Konrad

What would be the difference/advantage in using FIELD_PREP/GET instead 
of u32_encode_bits ?