Re: [PATCH 5/5] x86/amd_node: Output the AGESA version to the logs

[Yazen Ghannam <yazen.ghannam@amd.com>]

On Sun, Dec 14, 2025 at 12:53:09PM -0600, Mario Limonciello (AMD) wrote:
> On AMD Zen platforms that are running AGESA, there is sometimes
> DMI additional string for the AGESA version that can be helpful when
> debugging an issue.  If this string is found output to kernel logs.
> 
> Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
> ---
> This is not strictly AMD node related; it was a proxy for a good location
> for the message late enough on boot and only run on AMD Zen machines.
> I'm open to other suggestions.

Maybe do like print_s5_reset_status_mmio() with a late_initcall()?

We could have an amd_zen_late_initcall() function in
arch/x86/kernel/cpu/amd.c that collects appropriate functions.

We have two now:
 - print_s5_reset_status_mmio()
 - print_agesa_dmi_info()

Thanks,
Yazen

>  arch/x86/Kconfig           | 1 +
>  arch/x86/kernel/amd_node.c | 8 ++++++++
>  2 files changed, 9 insertions(+)
> 
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 80527299f859a..eae139a91fb84 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -3116,6 +3116,7 @@ config AMD_NB
>  config AMD_NODE
>  	def_bool y
>  	depends on CPU_SUP_AMD && PCI
> +	select DMI
>  
>  endmenu
>  
> diff --git a/arch/x86/kernel/amd_node.c b/arch/x86/kernel/amd_node.c
> index 3d0a4768d603c..575d727c5827e 100644
> --- a/arch/x86/kernel/amd_node.c
> +++ b/arch/x86/kernel/amd_node.c
> @@ -9,6 +9,7 @@
>   */
>  
>  #include <linux/debugfs.h>
> +#include <linux/dmi.h>
>  #include <asm/amd/node.h>
>  
>  /*
> @@ -247,6 +248,7 @@ __setup("amd_smn_debugfs_enable", amd_smn_enable_dfs);
>  static int __init amd_smn_init(void)
>  {
>  	u16 count, num_roots, roots_per_node, node, num_nodes;
> +	const struct dmi_device *dev = NULL;
>  	struct pci_dev *root;
>  
>  	if (!cpu_feature_enabled(X86_FEATURE_ZEN))
> @@ -310,6 +312,12 @@ static int __init amd_smn_init(void)
>  
>  	smn_exclusive = true;
>  
> +	while ((dev = dmi_find_device(DMI_DEV_TYPE_ADDITIONAL, NULL, dev)))
> +		if (!strncmp(dev->name, "AGESA", 5)) {
> +			pr_info("%s\n", dev->name);
> +			break;
> +		}
> +
>  	return 0;
>  }
>  
> -- 
> 2.43.0
>