[PATCH] drivers: ddr: altera: Check IOSSM mailbox compatibility

[Chee, Tien Fong]

> -----Original Message-----
> From: Ravulapalli, Naresh Kumar <naresh.kumar.ravulapalli at altera.com>
> Sent: Friday, August 8, 2025 5:37 PM
> To: u-boot at lists.denx.de
> Cc: Marek Vasut <marex at denx.de>; Simon Goldschmidt
> <simon.k.r.goldschmidt at gmail.com>; Chee, Tien Fong
> <tien.fong.chee at altera.com>; Tom Rini <trini at konsulko.com>; Ravulapalli,
> Naresh Kumar <naresh.kumar.ravulapalli at altera.com>
> Subject: [PATCH] drivers: ddr: altera: Check IOSSM mailbox compatibility
> 
> Compatibility check of IOSSM mailbox with U-Boot is performed by verifying
> the mailbox specification version. If check fails, appropriate error message is
> displayed.
> 
> Signed-off-by: Naresh Kumar Ravulapalli
> <nareshkumar.ravulapalli at altera.com>
> ---
>  drivers/ddr/altera/iossm_mailbox.c | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/drivers/ddr/altera/iossm_mailbox.c
> b/drivers/ddr/altera/iossm_mailbox.c
> index 21f94959a04..2a2f86a650e 100644
> --- a/drivers/ddr/altera/iossm_mailbox.c
> +++ b/drivers/ddr/altera/iossm_mailbox.c
> @@ -38,6 +38,8 @@
>  #define IOSSM_STATUS_CMD_RESPONSE_ERROR(n)
> 	FIELD_GET(IOSSM_STATUS_CMD_RESPONSE_ERROR_MASK, n)
>  #define IOSSM_STATUS_GENERAL_ERROR_MASK		GENMASK(4,
> 1)
>  #define IOSSM_STATUS_GENERAL_ERROR(n)
> 	FIELD_GET(IOSSM_STATUS_GENERAL_ERROR_MASK, n)
> +#define IOSSM_MAILBOX_SPEC_VERSION_MASK		GENMASK(2,
> 0)
> +#define IOSSM_MAILBOX_SPEC_VERSION(n)
> 	FIELD_GET(IOSSM_MAILBOX_SPEC_VERSION_MASK, n)
> 
>  /* Offset of Mailbox Read-only Registers  */
>  #define IOSSM_MAILBOX_HEADER_OFFSET			0x0
> @@ -383,6 +385,23 @@ err:
>  	return ret;
>  }
> 
> +static bool is_mailbox_spec_compatible(struct io96b_info *io96b_ctrl) {
> +	u32 mailbox_header;
> +	u8 mailbox_spec_ver;
> +
> +	mailbox_header = readl(io96b_ctrl->io96b[0].io96b_csr_addr +
> +				IOSSM_MAILBOX_HEADER_OFFSET);
> +	mailbox_spec_ver =
> IOSSM_MAILBOX_SPEC_VERSION(mailbox_header);
> +	printf("%s: IOSSM mailbox version: %d\n", __func__,
> mailbox_spec_ver);
> +
> +	/* for now there are two mailbox spec versions, 0 and 1; only version
> 1 is compatible */
> +	if (!mailbox_spec_ver)
> +		return false;
> +
> +	return true;
> +}
> +
>  /*
>   * Initial function to be called to set memory interface IP type and instance ID
>   * IP type and instance ID need to be determined before sending mailbox
> command @@ -392,6 +411,11 @@ void io96b_mb_init(struct io96b_info
> *io96b_ctrl)
>  	int i, j;
>  	u32 mem_intf_info_0, mem_intf_info_1;
> 
> +	if (!is_mailbox_spec_compatible(io96b_ctrl)) {
> +		printf("DDR: Failed to get compatible mailbox version\n");
> +		hang();
> +	}
> +
>  	debug("%s: num_instance %d\n", __func__, io96b_ctrl-
> >num_instance);
> 
>  	for (i = 0; i < io96b_ctrl->num_instance; i++) {
> --
> 2.35.3

Reviewed-by: Tien Fong Chee <tien.fong.chee at altera.com>

Best regards,
Tien Fong