[PATCH] ram: stm32mp1: Conditionally enable ASR

[Patrice CHOTARD]

Hi Marek

On 4/13/22 04:49, Marek Vasut wrote:
> Enable DRAM ASR, auto self-refresh, conditionally, based on DT property
> "st,mem-enable-asr" . While ASR does save considerable amount of power
> at runtime automatically, it also causes LTDC underruns on large panels.
> Let user select whether or not ASR is required or not, generally ASR
> should be enabled on portable and battery operated devices.
> 
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Patrick Delaunay <patrick.delaunay at foss.st.com>
> Cc: Patrice Chotard <patrice.chotard at foss.st.com>
> ---
>  drivers/ram/stm32mp1/stm32mp1_ddr.c | 3 ++-
>  drivers/ram/stm32mp1/stm32mp1_ddr.h | 1 +
>  drivers/ram/stm32mp1/stm32mp1_ram.c | 1 +
>  3 files changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/ram/stm32mp1/stm32mp1_ddr.c b/drivers/ram/stm32mp1/stm32mp1_ddr.c
> index 528a171b454..fd11e02aff4 100644
> --- a/drivers/ram/stm32mp1/stm32mp1_ddr.c
> +++ b/drivers/ram/stm32mp1/stm32mp1_ddr.c
> @@ -845,7 +845,8 @@ start:
>  				 config->c_reg.pwrctl);
>  
>  /* Enable auto-self-refresh, which saves a bit of power at runtime. */
> -	stm32mp1_asr_enable(priv);
> +	if (config->info.enable_asr)
> +		stm32mp1_asr_enable(priv);
>  
>  	/* enable uMCTL2 AXI port 0 and 1 */
>  	setbits_le32(&priv->ctl->pctrl_0, DDRCTRL_PCTRL_N_PORT_EN);
> diff --git a/drivers/ram/stm32mp1/stm32mp1_ddr.h b/drivers/ram/stm32mp1/stm32mp1_ddr.h
> index 861efff92be..c74a9cea2cc 100644
> --- a/drivers/ram/stm32mp1/stm32mp1_ddr.h
> +++ b/drivers/ram/stm32mp1/stm32mp1_ddr.h
> @@ -144,6 +144,7 @@ struct stm32mp1_ddr_info {
>  	const char *name;
>  	u32 speed; /* in kHZ */
>  	u32 size;  /* memory size in byte = col * row * width */
> +	bool enable_asr;
>  };
>  
>  struct stm32mp1_ddr_config {
> diff --git a/drivers/ram/stm32mp1/stm32mp1_ram.c b/drivers/ram/stm32mp1/stm32mp1_ram.c
> index 49b1262461b..f39cfad4764 100644
> --- a/drivers/ram/stm32mp1/stm32mp1_ram.c
> +++ b/drivers/ram/stm32mp1/stm32mp1_ram.c
> @@ -122,6 +122,7 @@ static int stm32mp1_ddr_setup(struct udevice *dev)
>  	config.info.speed = ofnode_read_u32_default(node, "st,mem-speed", 0);
>  	config.info.size = ofnode_read_u32_default(node, "st,mem-size", 0);
>  	config.info.name = ofnode_read_string(node, "st,mem-name");
> +	config.info.enable_asr = ofnode_read_bool(node, "st,mem-enable-asr");
>  	if (!config.info.name) {
>  		dev_dbg(dev, "no st,mem-name\n");
>  		return -EINVAL;

Reviewed-by: Patrice Chotard <patrice.chotard at foss.st.com>

Thanks
Patrice