drm/xe/device: Introduce xe_device_probe_early

SR-IOV VF doesn't have access to MMIO registers used to determine
graphics/media ID. It can however communicate with GuC.
Introduce xe_device_probe_early, which initializes enough HW to use
MMIO GuC communication.
This will allow both VF and PF/native driver to have unified probe
ordering.
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/xe/xe_device.c

@@ -375,6 +375,24 @@ static int xe_set_dma_info(struct xe_device *xe)
 	return err;
 }
 
+/*
+ * Initialize MMIO resources that don't require any knowledge about tile count.
+ */
+int xe_device_probe_early(struct xe_device *xe)
+{
+	int err;
+
+	err = xe_mmio_init(xe);
+	if (err)
+		return err;
+
+	err = xe_mmio_root_tile_init(xe);
+	if (err)
+		return err;
+
+	return 0;
+}
+
 int xe_device_probe(struct xe_device *xe)
 {
 	struct xe_tile *tile;
@@ -393,10 +411,6 @@ int xe_device_probe(struct xe_device *xe)
 	if (err)
 		return err;
 
-	err = xe_mmio_init(xe);
-	if (err)
-		return err;
-
 	xe_mmio_probe_tiles(xe);
 
 	err = drmm_add_action_or_reset(&xe->drm, xe_driver_flr_fini, xe);

drivers/gpu/drm/xe/xe_device.h

@@ -37,6 +37,7 @@ static inline struct xe_device *ttm_to_xe_device(struct ttm_device *ttm)
 
 struct xe_device *xe_device_create(struct pci_dev *pdev,
 				   const struct pci_device_id *ent);
+int xe_device_probe_early(struct xe_device *xe);
 int xe_device_probe(struct xe_device *xe);
 void xe_device_remove(struct xe_device *xe);
 void xe_device_shutdown(struct xe_device *xe);
@@ -123,6 +124,10 @@ static inline bool xe_device_uc_enabled(struct xe_device *xe)
 	for ((id__) = 0; (id__) < (xe__)->info.tile_count; (id__)++) \
 		for_each_if((tile__) = &(xe__)->tiles[(id__)])
 
+#define for_each_remote_tile(tile__, xe__, id__) \
+	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...

drivers/gpu/drm/xe/xe_mmio.c

@@ -15,10 +15,12 @@
 #include "regs/xe_regs.h"
 #include "xe_bo.h"
 #include "xe_device.h"
+#include "xe_ggtt.h"
 #include "xe_gt.h"
 #include "xe_gt_mcr.h"
 #include "xe_macros.h"
 #include "xe_module.h"
+#include "xe_tile.h"
 
 #define XEHP_MTCFG_ADDR		XE_REG(0x101800)
 #define TILE_COUNT		REG_GENMASK(15, 8)
@@ -376,10 +378,8 @@ static int xe_verify_lmem_ready(struct xe_device *xe)
 
 int xe_mmio_init(struct xe_device *xe)
 {
-	struct xe_tile *root_tile = xe_device_get_root_tile(xe);
 	struct pci_dev *pdev = to_pci_dev(xe->drm.dev);
 	const int mmio_bar = 0;
-	int err;
 
 	/*
 	 * Map the entire BAR.
@@ -393,12 +393,16 @@ int xe_mmio_init(struct xe_device *xe)
 		return -EIO;
 	}
 
-	err = drmm_add_action_or_reset(&xe->drm, mmio_fini, xe);
-	if (err)
-		return err;
+	return drmm_add_action_or_reset(&xe->drm, mmio_fini, xe);
+}
+
+int xe_mmio_root_tile_init(struct xe_device *xe)
+{
+	struct xe_tile *root_tile = xe_device_get_root_tile(xe);
+	int err;
 
 	/* Setup first tile; other tiles (if present) will be setup later. */
-	root_tile->mmio.size = xe->mmio.size;
+	root_tile->mmio.size = SZ_16M;
 	root_tile->mmio.regs = xe->mmio.regs;
 
 	err = xe_verify_lmem_ready(xe);

drivers/gpu/drm/xe/xe_mmio.h

@@ -21,6 +21,7 @@ struct xe_device;
 #define LMEM_BAR		2
 
 int xe_mmio_init(struct xe_device *xe);
+int xe_mmio_root_tile_init(struct xe_device *xe);
 void xe_mmio_probe_tiles(struct xe_device *xe);
 
 static inline u8 xe_mmio_read8(struct xe_gt *gt, struct xe_reg reg)

drivers/gpu/drm/xe/xe_pci.c

@@ -536,10 +536,12 @@ static void handle_gmdid(struct xe_device *xe,
  * Initialize device info content that only depends on static driver_data
  * passed to the driver at probe time from PCI ID table.
  */
-static void xe_info_init_early(struct xe_device *xe,
+static int xe_info_init_early(struct xe_device *xe,
 			      const struct xe_device_desc *desc,
 			      const struct xe_subplatform_desc *subplatform_desc)
 {
+	int err;
+
 	xe->info.platform = desc->platform;
 	xe->info.subplatform = subplatform_desc ?
 		subplatform_desc->subplatform : XE_SUBPLATFORM_NONE;
@@ -556,6 +558,12 @@ static void xe_info_init_early(struct xe_device *xe,
 	xe->info.enable_display = IS_ENABLED(CONFIG_DRM_XE_DISPLAY) &&
 				  xe_modparam.enable_display &&
 				  desc->has_display;
+
+	err = xe_tile_init_early(xe_device_get_root_tile(xe), xe, 0);
+	if (err)
+		return err;
+
+	return 0;
 }
 
 /*
@@ -623,13 +631,15 @@ static int xe_info_init(struct xe_device *xe,
 	 */
 	xe->info.tile_count = 1 + graphics_desc->max_remote_tiles;
 
-	for_each_tile(tile, xe, id) {
+	for_each_remote_tile(tile, xe, id) {
 		int err;
 
 		err = xe_tile_init_early(tile, xe, id);
 		if (err)
 			return err;
+	}
 
+	for_each_tile(tile, xe, id) {
 		gt = tile->primary_gt;
 		gt->info.id = xe->info.gt_count++;
 		gt->info.type = XE_GT_TYPE_MAIN;
@@ -723,10 +733,16 @@ static int xe_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	pci_set_master(pdev);
 
-	xe_info_init_early(xe, desc, subplatform_desc);
+	err = xe_info_init_early(xe, desc, subplatform_desc);
+	if (err)
+		return err;
 
 	xe_sriov_probe_early(xe, desc->has_sriov);
 
+	err = xe_device_probe_early(xe);
+	if (err)
+		return err;
+
 	err = xe_info_init(xe, desc->graphics, desc->media);
 	if (err)
 		return err;