[PATCH v3 25/25] drm/xe: Add modparam to enable / disable ULLS on migrate queue

Matthew Brost
2026-02-28T01:35:33Z

Having modparam to enable / disable ULLS on migrate queue will help with
quick experiments.

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
---
drivers/gpu/drm/xe/xe_debugfs.c | 1 +
drivers/gpu/drm/xe/xe_defaults.h | 1 +
drivers/gpu/drm/xe/xe_device.c | 12 +++++++++---
drivers/gpu/drm/xe/xe_device_types.h | 5 +++++
drivers/gpu/drm/xe/xe_migrate.c | 2 +-
drivers/gpu/drm/xe/xe_module.c | 4 ++++
drivers/gpu/drm/xe/xe_module.h | 1 +
7 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_debugfs.c b/drivers/gpu/drm/xe/xe_debugfs.c
index 844cfafe1ec7..049389205b3f 100644
--- a/drivers/gpu/drm/xe/xe_debugfs.c
+++ b/drivers/gpu/drm/xe/xe_debugfs.c
@@ -85,6 +85,7 @@ static int info(struct seq_file *m, void *data)
drm_printf(&p, "tile_count %d\n", xe->info.tile_count);
drm_printf(&p, "vm_max_level %d\n", xe->info.vm_max_level);
drm_printf(&p, "force_execlist %s\n", str_yes_no(xe->info.force_execlist));
+ drm_printf(&p, "ulls_enable %s\n", str_yes_no(xe->info.ulls_enable));
drm_printf(&p, "has_flat_ccs %s\n", str_yes_no(xe->info.has_flat_ccs));
drm_printf(&p, "has_usm %s\n", str_yes_no(xe->info.has_usm));
drm_printf(&p, "skip_guc_pc %s\n", str_yes_no(xe->info.skip_guc_pc));
diff --git a/drivers/gpu/drm/xe/xe_defaults.h b/drivers/gpu/drm/xe/xe_defaults.h
index c8ae1d5f3d60..299360546283 100644
--- a/drivers/gpu/drm/xe/xe_defaults.h
+++ b/drivers/gpu/drm/xe/xe_defaults.h
@@ -14,6 +14,7 @@
#endif

#define XE_DEFAULT_PROBE_DISPLAY IS_ENABLED(CONFIG_DRM_XE_DISPLAY)
+#define XE_DEFAULT_ULLS_ENABLE true
#define XE_DEFAULT_VRAM_BAR_SIZE 0
#define XE_DEFAULT_FORCE_PROBE CONFIG_DRM_XE_FORCE_PROBE
#define XE_DEFAULT_MAX_VFS ~0
diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
index b7ad7f97e68c..18af003c95c5 100644
--- a/drivers/gpu/drm/xe/xe_device.c
+++ b/drivers/gpu/drm/xe/xe_device.c
@@ -437,6 +437,14 @@ static void xe_device_destroy(struct drm_device *dev, void *dummy)
ttm_device_fini(&xe->ttm);
}

+static void xe_device_parse_modparam(struct xe_device *xe)
+{
+ xe->info.force_execlist = xe_modparam.force_execlist;
+ xe->info.ulls_enable = xe_modparam.ulls_enable;
+ xe->atomic_svm_timeslice_ms = 5;
+ xe->min_run_period_lr_ms = 5;
+}
+
struct xe_device *xe_device_create(struct pci_dev *pdev,
const struct pci_device_id *ent)
{
@@ -470,9 +478,7 @@ struct xe_device *xe_device_create(struct pci_dev *pdev,

xe->info.devid = pdev->device;
xe->info.revid = pdev->revision;
- xe->info.force_execlist = xe_modparam.force_execlist;
- xe->atomic_svm_timeslice_ms = 5;
- xe->min_run_period_lr_ms = 5;
+ xe_device_parse_modparam(xe);

err = xe_irq_init(xe);
if (err)
diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.h
index b3737dfcc45c..a20ff1707227 100644
--- a/drivers/gpu/drm/xe/xe_device_types.h
+++ b/drivers/gpu/drm/xe/xe_device_types.h
@@ -231,6 +231,11 @@ struct xe_device {
u8 skip_pcode:1;
/** @info.needs_shared_vf_gt_wq: needs shared GT WQ on VF */
u8 needs_shared_vf_gt_wq:1;
+ /**
+ * @info.ulls_enable: Enable ULLS on migration queue in LR VM
+ * open
+ */
+ u8 ulls_enable:1;
} info;

/** @wa_active: keep track of active workarounds */
diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
index 62f27868f56b..9f02e238e7c6 100644
--- a/drivers/gpu/drm/xe/xe_migrate.c
+++ b/drivers/gpu/drm/xe/xe_migrate.c
@@ -447,7 +447,7 @@ void xe_migrate_ulls_enter(struct xe_migrate *m)

xe_assert(xe, xe->info.has_usm);

- if (!IS_DGFX(xe) || IS_SRIOV_VF(xe))
+ if (!IS_DGFX(xe) || IS_SRIOV_VF(xe) || !xe->info.ulls_enable)
return;

job_alloc:
diff --git a/drivers/gpu/drm/xe/xe_module.c b/drivers/gpu/drm/xe/xe_module.c
index 4cb578182912..bb4fb967aec9 100644
--- a/drivers/gpu/drm/xe/xe_module.c
+++ b/drivers/gpu/drm/xe/xe_module.c
@@ -22,6 +22,7 @@

struct xe_modparam xe_modparam = {
.probe_display = XE_DEFAULT_PROBE_DISPLAY,
+ .ulls_enable = XE_DEFAULT_ULLS_ENABLE,
.guc_log_level = XE_DEFAULT_GUC_LOG_LEVEL,
.force_probe = XE_DEFAULT_FORCE_PROBE,
#ifdef CONFIG_PCI_IOV
@@ -45,6 +46,9 @@ MODULE_PARM_DESC(probe_display, "Probe display HW, otherwise it's left untouched
"[default=" __stringify(XE_DEFAULT_PROBE_DISPLAY) "])");
#endif

+module_param_named(ulls_enable, xe_modparam.ulls_enable, bool, 0444);
+MODULE_PARM_DESC(ulls_enable, "Enable ULLS on migration queue if LR VM open (default: true)");
+
module_param_named(vram_bar_size, xe_modparam.force_vram_bar_size, int, 0600);
MODULE_PARM_DESC(vram_bar_size, "Set the vram bar size in MiB (<0=disable-resize, 0=max-needed-size, >0=force-size "
"[default=" __stringify(XE_DEFAULT_VRAM_BAR_SIZE) "])");
diff --git a/drivers/gpu/drm/xe/xe_module.h b/drivers/gpu/drm/xe/xe_module.h
index 79cb9639c0f3..f0220b694c40 100644
--- a/drivers/gpu/drm/xe/xe_module.h
+++ b/drivers/gpu/drm/xe/xe_module.h
@@ -12,6 +12,7 @@
struct xe_modparam {
bool force_execlist;
bool probe_display;
+ bool ulls_enable;
int force_vram_bar_size;
int guc_log_level;
char *guc_firmware_path;
--
2.34.1