From: Matt Roper Date: Tue, 1 Jul 2025 20:13:27 +0000 (-0700) Subject: drm/xe: Don't compare GT ID to GT count when determining valid GTs X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=457123d5a0351792280c7441107db49560bdd3c3;p=thirdparty%2Fkernel%2Flinux.git drm/xe: Don't compare GT ID to GT count when determining valid GTs On current platforms with multiple GTs, all of the GT IDs are consecutive; as a result we know that the GT IDs range from 0 to gt_count-1 and can determine if a GT ID is valid by comparing against the count. The consecutive nature of GT IDs may not hold true on future platforms if/when we have platforms that are both multi-tile and have multiple GTs within each tile. Once such platforms exist, it's quite possible that we could wind up with something like a GT list composed of IDs 0, 2, and 3 with no GT 1 (which would be a 2-tile platform with media only on the second tile). To future-proof the code we should stop comparing against the GT count to determine whether a GT ID is valid or not. Instead we should do an actual lookup of the ID to determine whether the GT exists. This also means that our GT loop macro should not end at the GT count, but should rather examine the entire space up to (# of tiles) * (max GT per tile) to ensure it doesn't stop prematurely. Reviewed-by: Jonathan Cavitt Link: https://lore.kernel.org/r/20250701201320.2514369-15-matthew.d.roper@intel.com Signed-off-by: Matt Roper --- diff --git a/drivers/gpu/drm/xe/xe_device.h b/drivers/gpu/drm/xe/xe_device.h index 4e719d398c882..f0eb8150f1853 100644 --- a/drivers/gpu/drm/xe/xe_device.h +++ b/drivers/gpu/drm/xe/xe_device.h @@ -127,12 +127,8 @@ static inline bool xe_device_uc_enabled(struct xe_device *xe) for ((id__) = 1; (id__) < (xe__)->info.tile_count; (id__)++) \ for_each_if((tile__) = &(xe__)->tiles[(id__)]) -/* - * FIXME: This only works for now since multi-tile and standalone media - * happen to be mutually exclusive. Future platforms may change this... - */ #define for_each_gt(gt__, xe__, id__) \ - for ((id__) = 0; (id__) < (xe__)->info.gt_count; (id__)++) \ + for ((id__) = 0; (id__) < (xe__)->info.tile_count * (xe__)->info.max_gt_per_tile; (id__)++) \ for_each_if((gt__) = xe_device_get_gt((xe__), (id__))) static inline struct xe_force_wake *gt_to_fw(struct xe_gt *gt) diff --git a/drivers/gpu/drm/xe/xe_eu_stall.c b/drivers/gpu/drm/xe/xe_eu_stall.c index 96732613b4b7d..af7916315ac66 100644 --- a/drivers/gpu/drm/xe/xe_eu_stall.c +++ b/drivers/gpu/drm/xe/xe_eu_stall.c @@ -258,11 +258,13 @@ static int set_prop_eu_stall_wait_num_reports(struct xe_device *xe, u64 value, static int set_prop_eu_stall_gt_id(struct xe_device *xe, u64 value, struct eu_stall_open_properties *props) { - if (value >= xe->info.gt_count) { + struct xe_gt *gt = xe_device_get_gt(xe, value); + + if (!gt) { drm_dbg(&xe->drm, "Invalid GT ID %llu for EU stall sampling\n", value); return -EINVAL; } - props->gt = xe_device_get_gt(xe, value); + props->gt = gt; return 0; } diff --git a/drivers/gpu/drm/xe/xe_exec_queue.c b/drivers/gpu/drm/xe/xe_exec_queue.c index fee22358cc09b..8991b4aed4407 100644 --- a/drivers/gpu/drm/xe/xe_exec_queue.c +++ b/drivers/gpu/drm/xe/xe_exec_queue.c @@ -610,7 +610,7 @@ int xe_exec_queue_create_ioctl(struct drm_device *dev, void *data, if (XE_IOCTL_DBG(xe, err)) return -EFAULT; - if (XE_IOCTL_DBG(xe, eci[0].gt_id >= xe->info.gt_count)) + if (XE_IOCTL_DBG(xe, !xe_device_get_gt(xe, eci[0].gt_id))) return -EINVAL; if (args->flags & DRM_XE_EXEC_QUEUE_LOW_LATENCY_HINT) diff --git a/drivers/gpu/drm/xe/xe_hw_engine.c b/drivers/gpu/drm/xe/xe_hw_engine.c index 3439c8522d013..796ba8c34a160 100644 --- a/drivers/gpu/drm/xe/xe_hw_engine.c +++ b/drivers/gpu/drm/xe/xe_hw_engine.c @@ -1059,12 +1059,13 @@ struct xe_hw_engine * xe_hw_engine_lookup(struct xe_device *xe, struct drm_xe_engine_class_instance eci) { + struct xe_gt *gt = xe_device_get_gt(xe, eci.gt_id); unsigned int idx; if (eci.engine_class >= ARRAY_SIZE(user_to_xe_engine_class)) return NULL; - if (eci.gt_id >= xe->info.gt_count) + if (!gt) return NULL; idx = array_index_nospec(eci.engine_class,