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Bottomley" , "open list:ARM/QUALCOMM MAILING LIST" , open list References: <20250116091150.1167739-1-quic_ziqichen@quicinc.com> <20250116091150.1167739-5-quic_ziqichen@quicinc.com> <20250119073056.houuz5xjyeen7nw5@thinkpad> <20250120154135.xhrrmy37xdr6asmu@thinkpad> <12f4234b-91ca-48e2-8638-771acc15a7be@quicinc.com> <20250124053525.2sbefy4jitmzr6so@thinkpad> Content-Language: en-US From: Ziqi Chen In-Reply-To: <20250124053525.2sbefy4jitmzr6so@thinkpad> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nasanex01b.na.qualcomm.com (10.46.141.250) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: mNrugttpm7MkaH5o0-778hzefEIxI5ue X-Proofpoint-ORIG-GUID: mNrugttpm7MkaH5o0-778hzefEIxI5ue X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1057,Hydra:6.0.680,FMLib:17.12.68.34 definitions=2025-01-24_03,2025-01-23_01,2024-11-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 phishscore=0 spamscore=0 mlxlogscore=999 impostorscore=0 bulkscore=0 malwarescore=0 mlxscore=0 priorityscore=1501 adultscore=0 lowpriorityscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2411120000 definitions=main-2501240069 On 1/24/2025 1:35 PM, Manivannan Sadhasivam wrote: > On Tue, Jan 21, 2025 at 11:52:42AM +0800, Ziqi Chen wrote: >> >> >> On 1/20/2025 11:41 PM, Manivannan Sadhasivam wrote: >>> On Mon, Jan 20, 2025 at 08:07:07PM +0800, Ziqi Chen wrote: >>>> Hi Mani， >>>> >>>> Thanks for your comments~ >>>> >>>> On 1/19/2025 3:30 PM, Manivannan Sadhasivam wrote: >>>>> On Thu, Jan 16, 2025 at 05:11:45PM +0800, Ziqi Chen wrote: >>>>>> From: Can Guo >>>>>> >>>>>> Implement the freq_to_gear_speed() vops to map the unipro core clock >>>>>> frequency to the corresponding maximum supported gear speed. >>>>>> >>>>>> Co-developed-by: Ziqi Chen >>>>>> Signed-off-by: Ziqi Chen >>>>>> Signed-off-by: Can Guo >>>>>> --- >>>>>> drivers/ufs/host/ufs-qcom.c | 32 ++++++++++++++++++++++++++++++++ >>>>>> 1 file changed, 32 insertions(+) >>>>>> >>>>>> diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c >>>>>> index 1e8a23eb8c13..64263fa884f5 100644 >>>>>> --- a/drivers/ufs/host/ufs-qcom.c >>>>>> +++ b/drivers/ufs/host/ufs-qcom.c >>>>>> @@ -1803,6 +1803,37 @@ static int ufs_qcom_config_esi(struct ufs_hba *hba) >>>>>> return ret; >>>>>> } >>>>>> +static int ufs_qcom_freq_to_gear_speed(struct ufs_hba *hba, unsigned long freq, u32 *gear) >>>>>> +{ >>>>>> + int ret = 0 > >>>>> Please do not initialize ret with 0. Return the actual value directly. >>>>> >>>> >>>> If we don't initialize ret here, for the cases of freq matched in the table, >>>> it will return an unknown ret value. It is not make sense, right? >>>> >>>> Or you may want to say we don't need “ret” , just need to return gear value? >>>> But we need this "ret" to check whether the freq is invalid. >>>> >>> >>> I meant to say that you can just return 0 directly in success case and -EINVAL >>> in the case of error. >>> >> Hi Mani, >> >> If we don't print freq here , I think your suggestion is very good. If we >> print freq in this function , using "ret" to indicate success case and >> failure case and print freq an the end of this function is the way to avoid >> code bloat. >> >> How do you think about it? >> > > I don't understand how code bloat comes into picture here. I'm just asking for > this: > > static int ufs_qcom_freq_to_gear_speed(struct ufs_hba *hba, unsigned long freq, u32 *gear) > { > switch (freq) { > case 403000000: > *gear = UFS_HS_G5; > break; > ... > > default: > dev_err(hba->dev, "Unsupported clock freq: %ld\n", freq); > return -EINVAL; > } > > return 0; > } > >>>>>> + >>>>>> + switch (freq) { >>>>>> + case 403000000: >>>>>> + *gear = UFS_HS_G5; >>>>>> + break; >>>>>> + case 300000000: >>>>>> + *gear = UFS_HS_G4; >>>>>> + break; >>>>>> + case 201500000: >>>>>> + *gear = UFS_HS_G3; >>>>>> + break; >>>>>> + case 150000000: >>>>>> + case 100000000: >>>>>> + *gear = UFS_HS_G2; >>>>>> + break; >>>>>> + case 75000000: >>>>>> + case 37500000: >>>>>> + *gear = UFS_HS_G1; >>>>>> + break; >>>>>> + default: >>>>>> + ret = -EINVAL; >>>>>> + dev_err(hba->dev, "Unsupported clock freq\n"); >>>>> >>>>> Print the freq. >>>> >>>> Ok, thank for your suggestion, we can print freq with dev_dbg() in next >>>> version. >>>> >>> >>> No, use dev_err() with the freq. > >>> - Mani >>> >> I think use dev_err() here does not make sense: >> >> 1. This print is not an error message , just an information print. Using >> dev_err() reduces the readability of this code. > > Then why it was dev_err() in the first place? > >> 2. This prints will be print very frequent, I afraid it will increase the >> latency of clock scaling. >> > > First you need to decide whether this print should warn user or not. It is > telling users that the OPP table supplied a frequency that doesn't match the > gear speed. This can happen if there is a discrepancy between DT and the driver. > In that case, the users *should* be warned to fix the driver/DT. If you bury it > with dev_dbg(), no one will notice it. > > If your concern is with the frequency of logs, then use dev_err_ratelimited(). > > - Mani > I misunderstand your point Mani, I thought you want me to print freq for all cases... if you mean that print failure case, I already added it in patch V2. -Ziqi