[PATCH v1 03/10] ufs: host: mediatek: Add memory barrier for ref-clk control

[Bart Van Assche]

On 7/15/25 11:25 PM, peter.wang at mediatek.com wrote:
> +	/*
> +	 * Make sure that ref-clk on/off control register
> +	 * is writed done before read it.
> +	 */
> +	mb();

A memory barrier doesn't guarantee that an MMIO write has been
completed. A memory barrier enforces ordering of MMIO writes but does
not guarantee completion of MMIO writes. What you need is an MMIO read.
See e.g. commit 4bf3855497b6 ("scsi: ufs: core: Perform read back after 
disabling UIC_COMMAND_COMPL").

Bart.