[PATCH v1 02/10] ufs: host: mediatek: Add DDR_EN setting

Bart Van Assche bvanassche at acm.org
Wed Jul 16 08:22:34 PDT 2025


On 7/15/25 11:25 PM, peter.wang at mediatek.com wrote:
> On MT6989 and later platforms, control of DDR_EN has been switched from
> SPM to EMI. To prevent abnormal access to DRAM, it is necessary to wait
> for 'ddren_ack' or assert 'ddren_urgent' after sending 'ddren_req'.
> 
> This patch introduces the DDR_EN configuration in the UFS initialization
> flow, utilizing the assertion of 'ddren_urgent' to maintain performance.

What is SPM? What is EMI? What is DDR_EN? Please expand these acronyms.

> +/* UFS MTK ip version value */
> +enum {
> +	/* UFS 3.1 */
> +	IP_VER_MT6878    = 0x10420200,
> +
> +	/* UFS 4.0 */
> +	IP_VER_MT6897    = 0x10440000,
> +	IP_VER_MT6989    = 0x10450000,
> +
> +	IP_VER_NONE      = 0xFFFFFFFF
> +};

How can MediaTek IP versions be related to the UFS standard? Should
"UFS" perhaps be changed into "UFSHCI" in the above comments?

Thanks,

Bart.



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