[PATCH net-next v2 6/6] pds_core: add debugfs support for host backed memory

[Nikhil P. Rao]

From: Vamsi Atluri <Vamsi.Atluri@xxxxxxx>

Add debugfs file to display host memory allocations including tag,
size, order, and physical address for each memory request.

Signed-off-by: Vamsi Atluri <Vamsi.Atluri@xxxxxxx>
---
 drivers/net/ethernet/amd/pds_core/debugfs.c | 50 +++++++++++++++++++++++++++++
 drivers/net/ethernet/amd/pds_core/main.c    |  2 ++
 2 files changed, 52 insertions(+)

diff --git a/drivers/net/ethernet/amd/pds_core/debugfs.c b/drivers/net/ethernet/amd/pds_core/debugfs.c
index 04c5e3abd8d7..058071f6f17e 100644
--- a/drivers/net/ethernet/amd/pds_core/debugfs.c
+++ b/drivers/net/ethernet/amd/pds_core/debugfs.c
@@ -173,3 +173,53 @@ 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: %d\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, "%-6d %-12u %-6d 0x%llx\n",
+			   hm->tag, hm->size, hm->order,
+			   (unsigned long long)hm->pa);
+	}
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(host_mem);
+
+void pdsc_debugfs_add_host_mem(struct pdsc *pdsc)
+{
+	struct dentry *dentry;
+
+	if (!(pdsc->dev_ident.capabilities &
+	     cpu_to_le64(PDS_CORE_DEV_CAP_HOST_MEM)))
+		return;
+
+	/* Check if file already exists (e.g., during reset recovery) */
+	dentry = debugfs_lookup("host_mem", pdsc->dentry);
+	if (!IS_ERR_OR_NULL(dentry)) {
+		dput(dentry);
+		return;
+	}
+
+	debugfs_create_file("host_mem", 0400, pdsc->dentry,
+			    pdsc, &host_mem_fops);
+}
diff --git a/drivers/net/ethernet/amd/pds_core/main.c b/drivers/net/ethernet/amd/pds_core/main.c
index 58b4d77f6eca..aa7b5ce6f623 100644
--- a/drivers/net/ethernet/amd/pds_core/main.c
+++ b/drivers/net/ethernet/amd/pds_core/main.c
@@ -266,6 +266,8 @@ static int pdsc_init_pf(struct pdsc *pdsc)
 
 	mutex_unlock(&pdsc->config_lock);
 
+	pdsc_debugfs_add_host_mem(pdsc);
+
 	err = pdsc_auxbus_dev_add(pdsc, pdsc, PDS_DEV_TYPE_FWCTL, &pdsc->padev);
 	if (err)
 		goto err_out_stop;

-- 
2.43.0