[PATCH] drm: Ensure Proper Unload/Reload Order of MEI Modules for i915/Xe Driver

[Upadhyay, Tejas]

> -----Original Message-----
> From: Intel-xe <intel-xe-bounces at lists.freedesktop.org> On Behalf Of Bommu
> Krishnaiah
> Sent: Monday, September 2, 2024 7:41 PM
> To: intel-xe at lists.freedesktop.org
> Cc: Bommu, Krishnaiah <krishnaiah.bommu at intel.com>; Kamil Konieczny
> <kamil.konieczny at linux.intel.com>; Ceraolo Spurio, Daniele
> <daniele.ceraolospurio at intel.com>; De Marchi, Lucas
> <lucas.demarchi at intel.com>
> Subject: [PATCH] drm: Ensure Proper Unload/Reload Order of MEI Modules
> for i915/Xe Driver
> 
> This update addresses the unload/reload sequence of MEI modules in
> relation to the i915/Xe graphics driver. On platforms where the MEI hardware
> is integrated with the graphics device (e.g., DG2/BMG), the MEI modules
> depend on the i915/Xe driver. Conversely, on newer platforms like CLS, where
> the MEI hardware is separate, this dependency does not exist.
> 
> The changes introduced ensure that MEI modules are unloaded and reloaded
> in the correct order based on platform-specific dependencies. This is
> achieved by adding a MODULE_SOFTDEP directive to the i915 and Xe module
> code.
> 
> These changes enhance the robustness of MEI module handling across
> different hardware platforms, ensuring that the i915/Xe driver can be cleanly
> unloaded and reloaded without issues.
> 
> Signed-off-by: Bommu Krishnaiah <krishnaiah.bommu at intel.com>
> Cc: Kamil Konieczny <kamil.konieczny at linux.intel.com>
> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
> Cc: Lucas De Marchi <lucas.demarchi at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_module.c | 2 ++
>  drivers/gpu/drm/xe/xe_module.c     | 2 ++
>  2 files changed, 4 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_module.c
> b/drivers/gpu/drm/i915/i915_module.c
> index 65acd7bf75d0..2ad079ad35db 100644
> --- a/drivers/gpu/drm/i915/i915_module.c
> +++ b/drivers/gpu/drm/i915/i915_module.c
> @@ -75,6 +75,8 @@ static const struct {
>  };
>  static int init_progress;
> 
> +MODULE_SOFTDEP("pre: mei_gsc_proxy mei_gsc");
> +
>  static int __init i915_init(void)
>  {
>  	int err, i;
> diff --git a/drivers/gpu/drm/xe/xe_module.c
> b/drivers/gpu/drm/xe/xe_module.c index bfc3deebdaa2..5633ea1841b7
> 100644
> --- a/drivers/gpu/drm/xe/xe_module.c
> +++ b/drivers/gpu/drm/xe/xe_module.c
> @@ -127,6 +127,8 @@ static void xe_call_exit_func(unsigned int i)
>  	init_funcs[i].exit();
>  }
> 
> +MODULE_SOFTDEP("pre: mei_gsc_proxy mei_gsc");

Ok, I read it again, its " MEI modules depend on the i915/Xe driver ", should it be reverse? I got confused.

> +
>  static int __init xe_init(void)
>  {
>  	int err, i;
> --
> 2.25.1