[PATCH v2] drm: Ensure Proper Unload/Reload Order of MEI Modules for i915/Xe Driver

[Bommu Krishnaiah]

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 i915/xe driver is depend on the MEI
modules. Conversely, on newer platforms like MTL and LNL, 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.

v2: updated commit message

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>
Cc: Tejas Upadhyay <tejas.upadhyay 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");
+
 static int __init xe_init(void)
 {
 	int err, i;
-- 
2.25.1