drm/xe/pf: Allow to encode subset of VF configuration KLVs

We want to reuse format of the GuC KLVs while saving and restoring
VF configuration by the PF driver, but some of those KLVs (like
doorbell begin index or GGTT starting offset) are not strictly
needed to correctly restore VF configuration. Modify functions to
omit encoding of some of the KLVs with GuC only details.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240919171528.1451-4-michal.wajdeczko@intel.com

1 files changed, 19 insertions, 13 deletions

diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
index 27a593b1d52a..28e2b26c2d88 100644
--- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
+++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
@@ -229,14 +229,16 @@ static struct xe_gt_sriov_config *pf_pick_vf_config(struct xe_gt *gt, unsigned i
 }
 
 /* Return: number of configuration dwords written */
-static u32 encode_config_ggtt(u32 *cfg, const struct xe_gt_sriov_config *config)
+static u32 encode_config_ggtt(u32 *cfg, const struct xe_gt_sriov_config *config, bool details)
 {
 	u32 n = 0;
 
 	if (xe_ggtt_node_allocated(config->ggtt_region)) {
-		cfg[n++] = PREP_GUC_KLV_TAG(VF_CFG_GGTT_START);
-		cfg[n++] = lower_32_bits(config->ggtt_region->base.start);
-		cfg[n++] = upper_32_bits(config->ggtt_region->base.start);
+		if (details) {
+			cfg[n++] = PREP_GUC_KLV_TAG(VF_CFG_GGTT_START);
+			cfg[n++] = lower_32_bits(config->ggtt_region->base.start);
+			cfg[n++] = upper_32_bits(config->ggtt_region->base.start);
+		}
 
 		cfg[n++] = PREP_GUC_KLV_TAG(VF_CFG_GGTT_SIZE);
 		cfg[n++] = lower_32_bits(config->ggtt_region->base.size);
@@ -247,20 +249,24 @@ static u32 encode_config_ggtt(u32 *cfg, const struct xe_gt_sriov_config *config)
 }
 
 /* Return: number of configuration dwords written */
-static u32 encode_config(u32 *cfg, const struct xe_gt_sriov_config *config)
+static u32 encode_config(u32 *cfg, const struct xe_gt_sriov_config *config, bool details)
 {
 	u32 n = 0;
 
-	n += encode_config_ggtt(cfg, config);
+	n += encode_config_ggtt(cfg, config, details);
 
-	cfg[n++] = PREP_GUC_KLV_TAG(VF_CFG_BEGIN_CONTEXT_ID);
-	cfg[n++] = config->begin_ctx;
+	if (details) {
+		cfg[n++] = PREP_GUC_KLV_TAG(VF_CFG_BEGIN_CONTEXT_ID);
+		cfg[n++] = config->begin_ctx;
+	}
 
 	cfg[n++] = PREP_GUC_KLV_TAG(VF_CFG_NUM_CONTEXTS);
 	cfg[n++] = config->num_ctxs;
 
-	cfg[n++] = PREP_GUC_KLV_TAG(VF_CFG_BEGIN_DOORBELL_ID);
-	cfg[n++] = config->begin_db;
+	if (details) {
+		cfg[n++] = PREP_GUC_KLV_TAG(VF_CFG_BEGIN_DOORBELL_ID);
+		cfg[n++] = config->begin_db;
+	}
 
 	cfg[n++] = PREP_GUC_KLV_TAG(VF_CFG_NUM_DOORBELLS);
 	cfg[n++] = config->num_dbs;
@@ -301,7 +307,7 @@ static int pf_push_full_vf_config(struct xe_gt *gt, unsigned int vfid)
 	if (!cfg)
 		return -ENOMEM;
 
-	num_dwords = encode_config(cfg, config);
+	num_dwords = encode_config(cfg, config, true);
 	xe_gt_assert(gt, num_dwords <= max_cfg_dwords);
 
 	if (xe_gt_is_media_type(gt)) {
@@ -309,10 +315,10 @@ static int pf_push_full_vf_config(struct xe_gt *gt, unsigned int vfid)
 		struct xe_gt_sriov_config *other = pf_pick_vf_config(primary, vfid);
 
 		/* media-GT will never include a GGTT config */
-		xe_gt_assert(gt, !encode_config_ggtt(cfg + num_dwords, config));
+		xe_gt_assert(gt, !encode_config_ggtt(cfg + num_dwords, config, true));
 
 		/* the GGTT config must be taken from the primary-GT instead */
-		num_dwords += encode_config_ggtt(cfg + num_dwords, other);
+		num_dwords += encode_config_ggtt(cfg + num_dwords, other, true);
 	}
 	xe_gt_assert(gt, num_dwords <= max_cfg_dwords);