[Intel-gfx] [PATCH 20/27] drm/i915/pxp: Create the arbitrary session after boot

[Joonas Lahtinen]

Quoting Huang, Sean Z (2020-11-15 23:08:08)
> Create the arbitrary session, with the fixed session id 0xf, after
> system boot, for the case that application allocates the protected
> buffer without establishing any protection session. Because the
> hardware requires at least one alive session for protected buffer
> creation.  This arbitrary session needs to be re-created after
> teardown or power event because hardware encryption key won't be
> valid after such cases.
> 
> Signed-off-by: Huang, Sean Z <sean.z.huang at intel.com>

<SNIP>

> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.h
> @@ -16,4 +16,10 @@ int pxp_tee_ioctl_io_message(struct drm_i915_private *i915,
>                              void __user *msg_out_user_ptr, u32 *msg_out_size_ptr,
>                              u32 msg_out_buf_size);
>  
> +int intel_pxp_tee_cmd_create_arb_session(struct drm_i915_private *i915);
> +
> +/* TEE command to create the arbitrary session */
> +#define PXP_TEE_ARB_CMD_BIN  {0x00040000, 0x0000001e, 0x00000000, 0x00000008, 0x00000002, 0x0000000f}
> +#define PXP_TEE_ARB_CMD_DW_LEN (6)

This is a BLOB so it doesn't belong to kernel source code. It could be
considered in linux-firmware. As it's only an init sequence I'm not sure
how that will be perceived.

Probably best to ask.

Regards, Joonas