pds_core: add debugfs support for host backed memory

Add debugfs entry to dump host backed memory allocations for debug
purposes.

Signed-off-by: Vamsi Atluri <Vamsi.Atluri@amd.com>
Signed-off-by: Nikhil P. Rao <nikhil.rao@amd.com>
Link: https://patch.msgid.link/20260730-upstream_v8-v12-6-136cd174ee85@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

3 files changed, 48 insertions, 0 deletions

diff --git a/drivers/net/ethernet/amd/pds_core/core.c b/drivers/net/ethernet/amd/pds_core/core.c
index 26ddcbbfc14c..922e3ec8af1b 100644
--- a/drivers/net/ethernet/amd/pds_core/core.c
+++ b/drivers/net/ethernet/amd/pds_core/core.c
@@ -506,6 +506,7 @@ void pdsc_teardown(struct pdsc *pdsc, bool removing)
 		pdsc->viftype_status = NULL;
 	}
 
+	pdsc_debugfs_del_host_mem(pdsc);
 	pdsc_host_mem_free(pdsc);
 	pdsc_dev_uninit(pdsc);
 
@@ -517,6 +518,7 @@ int pdsc_start(struct pdsc *pdsc)
 	pds_core_intr_mask(&pdsc->intr_ctrl[pdsc->adminqcq.intx],
 			   PDS_CORE_INTR_MASK_CLEAR);
 	pdsc_host_mem_add(pdsc);
+	pdsc_debugfs_add_host_mem(pdsc);
 
 	return 0;
 }
diff --git a/drivers/net/ethernet/amd/pds_core/core.h b/drivers/net/ethernet/amd/pds_core/core.h
index 085f2e988aa0..791756a50870 100644
--- a/drivers/net/ethernet/amd/pds_core/core.h
+++ b/drivers/net/ethernet/amd/pds_core/core.h
@@ -306,6 +306,7 @@ void pdsc_debugfs_add_irqs(struct pdsc *pdsc);
 void pdsc_debugfs_add_qcq(struct pdsc *pdsc, struct pdsc_qcq *qcq);
 void pdsc_debugfs_del_qcq(struct pdsc_qcq *qcq);
 void pdsc_debugfs_add_host_mem(struct pdsc *pdsc);
+void pdsc_debugfs_del_host_mem(struct pdsc *pdsc);
 
 int pdsc_err_to_errno(enum pds_core_status_code code);
 bool pdsc_is_fw_running(struct pdsc *pdsc);
diff --git a/drivers/net/ethernet/amd/pds_core/debugfs.c b/drivers/net/ethernet/amd/pds_core/debugfs.c
index 810a0cd9bcac..ef0a1b7d159b 100644
--- a/drivers/net/ethernet/amd/pds_core/debugfs.c
+++ b/drivers/net/ethernet/amd/pds_core/debugfs.c
@@ -178,3 +178,48 @@ void pdsc_debugfs_del_qcq(struct pdsc_qcq *qcq)
 	debugfs_remove_recursive(qcq->dentry);
 	qcq->dentry = NULL;
 }
+
+static int host_mem_show(struct seq_file *seq, void *v)
+{
+	struct pdsc *pdsc = seq->private;
+	struct pdsc_host_mem *hm;
+	int i;
+
+	if (!pdsc->host_mem_reqs || pdsc->num_host_mem_reqs == 0) {
+		seq_puts(seq, "No host memory allocated\n");
+		return 0;
+	}
+
+	seq_printf(seq, "Host memory requests: %u\n\n",
+		   pdsc->num_host_mem_reqs);
+	seq_puts(seq, "Tag    Size         Order  PA\n");
+	seq_puts(seq, "---    ----         -----  --\n");
+
+	for (i = 0; i < pdsc->num_host_mem_reqs; i++) {
+		hm = &pdsc->host_mem_reqs[i];
+
+		if (!hm->pg)
+			continue;
+
+		seq_printf(seq, "%-6u %-12u %-6u %pad\n",
+			   hm->tag, hm->size, hm->order, &hm->pa);
+	}
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(host_mem);
+
+void pdsc_debugfs_add_host_mem(struct pdsc *pdsc)
+{
+	if (!(pdsc->dev_ident.capabilities &
+	     cpu_to_le64(PDS_CORE_DEV_CAP_HOST_MEM)))
+		return;
+
+	debugfs_create_file("host_mem", 0400, pdsc->dentry,
+			    pdsc, &host_mem_fops);
+}
+
+void pdsc_debugfs_del_host_mem(struct pdsc *pdsc)
+{
+	debugfs_lookup_and_remove("host_mem", pdsc->dentry);
+}