drm/xe/xe_late_bind_fw: Introduce debug fs node to disable late binding

Introduce a debug filesystem node to disable late binding fw reload
during the system or runtime resume. This is intended for situations
where the late binding fw needs to be loaded from user mode,
perticularly for validation purpose.
Note that xe kmd doesn't participate in late binding flow from user
space. Binary loaded from the userspace will be lost upon entering to
D3 cold hence user space app need to handle this situation.

v2:
  - s/(uval == 1) ? true : false/!!uval/ (Daniele)
v3:
  - Refine the commit message (Daniele)

Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Badal Nilawar <badal.nilawar@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://lore.kernel.org/r/20250905154953.3974335-9-badal.nilawar@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>

diff --git a/drivers/gpu/drm/xe/xe_debugfs.c b/drivers/gpu/drm/xe/xe_debugfs.c
index d67e32ebbe291c19d25224f7e54e804b755b2667..cd977dbd1ef63e624692589c7aecb70e18206cdf 100644 (file)
--- a/drivers/gpu/drm/xe/xe_debugfs.c
+++ b/drivers/gpu/drm/xe/xe_debugfs.c
@@ -331,6 +331,44 @@ static const struct file_operations atomic_svm_timeslice_ms_fops = {
        .write = atomic_svm_timeslice_ms_set,
 };
 
+static ssize_t disable_late_binding_show(struct file *f, char __user *ubuf,
+                                        size_t size, loff_t *pos)
+{
+       struct xe_device *xe = file_inode(f)->i_private;
+       struct xe_late_bind *late_bind = &xe->late_bind;
+       char buf[32];
+       int len;
+
+       len = scnprintf(buf, sizeof(buf), "%d\n", late_bind->disable);
+
+       return simple_read_from_buffer(ubuf, size, pos, buf, len);
+}
+
+static ssize_t disable_late_binding_set(struct file *f, const char __user *ubuf,
+                                       size_t size, loff_t *pos)
+{
+       struct xe_device *xe = file_inode(f)->i_private;
+       struct xe_late_bind *late_bind = &xe->late_bind;
+       u32 uval;
+       ssize_t ret;
+
+       ret = kstrtouint_from_user(ubuf, size, sizeof(uval), &uval);
+       if (ret)
+               return ret;
+
+       if (uval > 1)
+               return -EINVAL;
+
+       late_bind->disable = !!uval;
+       return size;
+}
+
+static const struct file_operations disable_late_binding_fops = {
+       .owner = THIS_MODULE,
+       .read = disable_late_binding_show,
+       .write = disable_late_binding_set,
+};
+
 void xe_debugfs_register(struct xe_device *xe)
 {
        struct ttm_device *bdev = &xe->ttm;
@@ -364,6 +402,9 @@ void xe_debugfs_register(struct xe_device *xe)
        debugfs_create_file("atomic_svm_timeslice_ms", 0600, root, xe,
                            &atomic_svm_timeslice_ms_fops);
 
+       debugfs_create_file("disable_late_binding", 0600, root, xe,
+                           &disable_late_binding_fops);
+
        for (mem_type = XE_PL_VRAM0; mem_type <= XE_PL_VRAM1; ++mem_type) {
                man = ttm_manager_type(bdev, mem_type);
 

diff --git a/drivers/gpu/drm/xe/xe_late_bind_fw.c b/drivers/gpu/drm/xe/xe_late_bind_fw.c
index d4d64677bf48b14111eb3e5b2bfb2578c1c439ee..0f062008ca836606556286dc167dbb427fdb34b1 100644 (file)
--- a/drivers/gpu/drm/xe/xe_late_bind_fw.c
+++ b/drivers/gpu/drm/xe/xe_late_bind_fw.c
@@ -167,6 +167,9 @@ int xe_late_bind_fw_load(struct xe_late_bind *late_bind)
        if (!late_bind->component_added)
                return -ENODEV;
 
+       if (late_bind->disable)
+               return 0;
+
        for (fw_id = 0; fw_id < XE_LB_FW_MAX_ID; fw_id++) {
                lbfw = &late_bind->late_bind_fw[fw_id];
                if (lbfw->payload) {

diff --git a/drivers/gpu/drm/xe/xe_late_bind_fw_types.h b/drivers/gpu/drm/xe/xe_late_bind_fw_types.h
index 5c0574aff7b95fdd370b9e82851e1bb4327d5a36..158dc1abe0724f9cbaf39b1578a16b604222cd21 100644 (file)
--- a/drivers/gpu/drm/xe/xe_late_bind_fw_types.h
+++ b/drivers/gpu/drm/xe/xe_late_bind_fw_types.h
@@ -65,6 +65,8 @@ struct xe_late_bind {
        struct workqueue_struct *wq;
        /** @component_added: whether the component has been added */
        bool component_added;
+       /** @disable: to block late binding reload during pm resume flow*/
+       bool disable;
 };
 
 #endif