Re: [PATCH] misc: open-dice: add ACPI device discovery support

[Greg Kroah-Hartman]

On Wed, Jul 15, 2026 at 08:18:20AM +0000, Song Guo wrote:
> OpenDICE can also used on x86 platforms for attestation, one of the
> usecase is Android's protected VM.
> 
> The OpenDICE device driver only supports device tree, adding ACPI
> support so it can also be used on x86 environments easily.
> 
> The patch is verified using crosvm, with the following ACPI table passed
> using --acpi-table, with --file-backed-mapping for the corresponding
> memory region.
> 
> DefinitionBlock (
>     "opendice.aml", "SSDT", 2, "GOOGLE", "OpenDICE", 0x00000001
> )
> {
>     Scope (\_SB)
>     {
>         Device (DICE)
>         {
>             Name (_HID, "PRP0001")
> 
>             Name (_DSD, Package () {
>                 ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
>                 Package () {
>                     Package () {
>                         "compatible",
>                         Package () { "google,open-dice" }
>                     }
>                 }
>             })
> 
>             Name (_CRS, ResourceTemplate () {
>                 Memory32Fixed (ReadOnly, 0x9D1C3000, 0x00001000)
>             })
>         }
>     }
> }
> 
> Signed-off-by: Song Guo <songguo@xxxxxxxxxx>
> ---
>  drivers/misc/open-dice.c | 51 +++++++++++++++++++++++++++++-----------
>  1 file changed, 37 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/misc/open-dice.c b/drivers/misc/open-dice.c
> index 45060fb4ea27..303b35b03cb4 100644
> --- a/drivers/misc/open-dice.c
> +++ b/drivers/misc/open-dice.c
> @@ -2,6 +2,7 @@
>  /*
>   * Copyright (C) 2021 - Google LLC
>   * Author: David Brazdil <dbrazdil@xxxxxxxxxx>
> + * Author: Song Guo <songguo@xxxxxxxxxx>
>   *
>   * Driver for Open Profile for DICE.
>   *
> @@ -19,6 +20,7 @@
>   *     close(fd);
>   */
>  
> +#include <linux/acpi.h>
>  #include <linux/io.h>
>  #include <linux/miscdevice.h>
>  #include <linux/mm.h>
> @@ -31,7 +33,8 @@
>  struct open_dice_drvdata {
>  	struct mutex lock;
>  	char name[16];
> -	struct reserved_mem *rmem;
> +	phys_addr_t mem_base;
> +	resource_size_t mem_size;

Shouldn't this be a 2 patch series, the first converting to use these
two variables instead of reserved_mem, and the second adding ACPI
support?  Otherwise you are mixing the two different things here and
it's a bit hard to follow.

thanks,

greg k-h