Re: [RFC PATCH v1 2/2] scsi: ufs: ufs-exynos: implement exynos isr

[Bart Van Assche <bvanassche@acm.org>]

On 8/5/21 11:34 PM, Kiwoong Kim wrote:
> Based on some events in the real world

Which events? Please clarify.

> I implement
> this to block the host's working in some abnormal
> conditions using an vendor specific interrupt for
> cases that some contexts of a pending request in the
> host isn't the same with those of its corresponding UPIUs
> if they should have been the same exactly.

The entire patch description sounds very vague to me. Please make the 
description more clear.

> +enum exynos_ufs_vs_interrupt {
> +	/*
> +	 * This occurs when information of a pending request isn't
> +	 * the same with incoming UPIU for the request. For example,
> +	 * if UFS driver rings with task tag #1, subsequential UPIUs
> +	 * for this must have one as the value of task tag. But if
> +	 * it's corrutped until the host receives it or incoming UPIUs
> +	 * has an unexpected value for task tag, this raises.
> +	 */
> +	RX_UPIU_HIT_ERROR	= 1 << 19,
> +};

The above description needs to be improved. If a request is submitted 
with task tag one, only one UPIU can have that task tag instead of all 
subsequent UPIUs.

>   	hci_writel(ufs, UFS_SW_RST_MASK, HCI_SW_RST);
> -
>   	do {
>   		if (!(hci_readl(ufs, HCI_SW_RST) & UFS_SW_RST_MASK))
> -			goto out;
> +			return 0;
>   	} while (time_before(jiffies, timeout));

Since the above loop is a busy-waiting loop, please insert an msleep() 
or cpu_relax() call.

> +	 * some unexpected events could happen, such as tranferring
                                                         ^^^^^^^^^^^
Please fix the spelling of this word.

Thanks,

Bart.