[PATCH v1 3/5] ddr: altera: gen5: Add DRAM size checking

[Chee, Tien Fong]

On 16/12/2025 4:46 pm, alif.zakuan.yuslaimi at altera.com wrote:
> From: Alif Zakuan Yuslaimi <alif.zakuan.yuslaimi at altera.com>
>
> Add DRAM size checking compare between size from device tree and actual
> hardware.
>
> Trigger hang if DRAM size from device tree is greater than actual hardware.
> Display warning message if DRAM size mismatch between device tree and
> actual hardware.
>
> get_ram_size() uses size from device tree. So, it has consistency with
> other device families.
>
> Signed-off-by: Alif Zakuan Yuslaimi <alif.zakuan.yuslaimi at altera.com>
> ---
>   drivers/ddr/altera/sdram_gen5.c | 20 +++++++++++++++++++-
>   1 file changed, 19 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/ddr/altera/sdram_gen5.c b/drivers/ddr/altera/sdram_gen5.c
> index 7a0a043557b..d5892850da7 100644
> --- a/drivers/ddr/altera/sdram_gen5.c
> +++ b/drivers/ddr/altera/sdram_gen5.c
> @@ -6,6 +6,7 @@
>   #include <dm.h>
>   #include <errno.h>
>   #include <div64.h>
> +#include <hang.h>
>   #include <init.h>
>   #include <log.h>
>   #include <ram.h>
> @@ -615,6 +616,22 @@ static int altera_gen5_sdram_probe(struct udevice *dev)
>   	sdram_size = sdram_calculate_size(sdr_ctrl);
>   	debug("SDRAM: %ld MiB\n", sdram_size >> 20);
>   
> +	/* setup the dram info within bd */
> +	dram_init_banksize();
> +
> +	if (sdram_size != gd->bd->bi_dram[0].size) {
> +		printf("DDR: Warning: DRAM size from device tree (%d MiB)\n",
> +		       (u32)(gd->bd->bi_dram[0].size >> 20));
> +		printf(" mismatch with hardware (%d MiB).\n",
> +		       (u32)(sdram_size >> 20));
> +	}
> +
> +	if (gd->bd->bi_dram[0].size > sdram_size) {
> +		printf("DDR: Error: DRAM size from device tree is greater\n");
> +		printf(" than hardware size.\n");
> +		hang();
> +	}
> +
>   	if (sdram_is_ecc_enabled(sdr_ctrl)) {
>   		/* Must set USEECCASDATA to 0 if ECC is enabled */
>   		clrbits_le32(&sdr_ctrl->static_cfg,
> @@ -623,7 +640,8 @@ static int altera_gen5_sdram_probe(struct udevice *dev)
>   	}
>   
>   	/* Sanity check ensure correct SDRAM size specified */
> -	if (get_ram_size(0, sdram_size) != sdram_size) {
> +	if (get_ram_size(0, gd->bd->bi_dram[0].size) !=
> +			 gd->bd->bi_dram[0].size) {
>   		puts("SDRAM size check failed!\n");
>   		goto failed;
>   	}


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

Best regards,
Tien Fong