Message-ID: <9ff005f0-0cef-65d6-6f69-8394f1ba3e3c@quicinc.com>
Date:   Mon, 30 Jan 2023 12:03:45 +0800
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Subject: Re: [PATCH] scsi: ufs: qcom: fix platform_msi_domain_free_irqs()
 reference
To:     Manivannan Sadhasivam <mani@kernel.org>,
        Arnd Bergmann <arnd@kernel.org>
CC:     "James E.J. Bottomley" <jejb@linux.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Arnd Bergmann <arnd@arndb.de>, Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        Bart Van Assche <bvanassche@acm.org>,
        Avri Altman <avri.altman@wdc.com>,
        Bean Huo <beanhuo@micron.com>, Jason Gunthorpe <jgg@ziepe.ca>,
        Thomas Gleixner <tglx@linutronix.de>,
        <linux-scsi@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-arm-msm@vger.kernel.org>
References: <20230126211831.2274211-1-arnd@kernel.org>
 <20230127060221.GB7809@thinkpad>
Content-Language: en-US
From:   Can Guo <quic_cang@quicinc.com>
In-Reply-To: <20230127060221.GB7809@thinkpad>
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Hi Mani and Arnd,

On 1/27/2023 2:02 PM, Manivannan Sadhasivam wrote:
> On Thu, Jan 26, 2023 at 10:17:31PM +0100, Arnd Bergmann wrote:
>> From: Arnd Bergmann <arnd@arndb.de>
>>
>> The newly added MSI support is mostly hidden inside of an #ifdef,
>> except for one line that now causes a build failure when MSI
>> is disabled:
>>
>> drivers/ufs/host/ufs-qcom.c: In function 'ufs_qcom_remove':
>> drivers/ufs/host/ufs-qcom.c:1698:9: error: implicit declaration of function 'platform_msi_domain_free_irqs' [-Werror=i]
>>   1698 |         platform_msi_domain_free_irqs(hba->dev);
>>        |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>
>> Above that, the symbol that guards the other call was recently
>> removed, so that is all dead code at the moment.
>>
>> Remove the incorrect #ifdef and instead of a Kconfig dependency
>> to only allow building the driver when CONFIG_GENERIC_MSI_IRQ
>> is enabled. This symbol is always present when PCI_MSI
>> or ARM_GIC_V3_ITS are enabled, both of which should be present
>> on kernels that can run on Qualcomm SoCs.
>>
>> The 'select RESET_CONTROLLER' in combination with this dependency
>> unfortunately causes a dependency loop and this is a user-visible
>> symbol, so it's better to change both to 'depends on'.
>>
>> Fixes: 519b6274a777 ("scsi: ufs: qcom: Add MCQ ESI config vendor specific ops")
>> Fixes: 13e7accb81d6 ("genirq: Get rid of GENERIC_MSI_IRQ_DOMAIN")
>> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
>
>> ---
>> Not sure if this is the best solution, both the GENERIC_MSI_IRQ
>> dependencies and the RESET_CONTROLLER dependencies are a bit
>> inconsistent already. Feel free to pick another approach that
>> addresses both of the bugs I found.
> I think your proposed solution works best at the moment.
>
> Thanks,
> Mani
>
>> ---
>>   drivers/ufs/host/Kconfig    | 3 ++-
>>   drivers/ufs/host/ufs-qcom.c | 8 --------
>>   2 files changed, 2 insertions(+), 9 deletions(-)
>>
>> diff --git a/drivers/ufs/host/Kconfig b/drivers/ufs/host/Kconfig
>> index 139064e70a34..663881437921 100644
>> --- a/drivers/ufs/host/Kconfig
>> +++ b/drivers/ufs/host/Kconfig
>> @@ -57,8 +57,9 @@ config SCSI_UFS_DWC_TC_PLATFORM
>>   config SCSI_UFS_QCOM
>>   	tristate "QCOM specific hooks to UFS controller platform driver"
>>   	depends on SCSI_UFSHCD_PLATFORM && ARCH_QCOM
>> +	depends on GENERIC_MSI_IRQ
>> +	depends on RESET_CONTROLLER
>>   	select QCOM_SCM if SCSI_UFS_CRYPTO
>> -	select RESET_CONTROLLER
>>   	help
>>   	  This selects the QCOM specific additions to UFSHCD platform driver.
>>   	  UFS host on QCOM needs some vendor specific configuration before
>> diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
>> index 681da3ea7154..eb66b5f6cf19 100644
>> --- a/drivers/ufs/host/ufs-qcom.c
>> +++ b/drivers/ufs/host/ufs-qcom.c
>> @@ -1538,7 +1538,6 @@ static int ufs_qcom_get_outstanding_cqs(struct ufs_hba *hba,
>>   	return 0;
>>   }
>>   
>> -#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
>>   static void ufs_qcom_write_msi_msg(struct msi_desc *desc, struct msi_msg *msg)
>>   {
>>   	struct device *dev = msi_desc_to_dev(desc);
>> @@ -1626,13 +1625,6 @@ static int ufs_qcom_config_esi(struct ufs_hba *hba)
>>   	return ret;
>>   }
>>   
>> -#else
>> -static int ufs_qcom_config_esi(struct ufs_hba *hba)
>> -{
>> -	return -EOPNOTSUPP;
>> -}
>> -#endif
>> -
>>   /*
>>    * struct ufs_hba_qcom_vops - UFS QCOM specific variant operations
>>    *
>> -- 
>> 2.39.0
>>

Thank you for pointing to 13e7accb81d6 ("genirq: Get rid of 
GENERIC_MSI_IRQ_DOMAIN"),

which I was not aware of. I am thinking about fixing it just like how

13e7accb81d6 ("genirq: Get rid of GENERIC_MSI_IRQ_DOMAIN") is fixing 
drivers/dma/qcom/hidma.c -

In ufs-qcom.c, use CONFIG_GENERIC_MSI_IRQ instead of 
CONFIG_GENERIC_MSI_IRQ_DOMAIN,

and meanwhile add #ifdef check before calling 
platform_msi_domain_free_irqs().

Please let me know your idea.


Thanks.
Regards,
Can Guo