[net-next PATCH v2 2/3] octeontx2-af: cn10k: debugfs for dumping LMTST map table

[Rakesh Babu]

From: Harman Kalra <hkalra@xxxxxxxxxxx>

CN10k SoCs use atomic stores of up to 128 bytes to submit
packets/instructions into co-processor cores. The enqueueing is performed
using Large Memory Transaction Store (LMTST) operations. They allow for
lockless enqueue operations - i.e., two different CPU cores can submit
instructions to the same queue without needing to lock the queue or
synchronize their accesses.

This patch implements a new debugfs entry for dumping LMTST map
table present on CN10K, as this might be very useful to debug any issue
in case of shared LMTST region among multiple pci functions.

Signed-off-by: Harman Kalra <hkalra@xxxxxxxxxxx>
Signed-off-by: Bhaskara Budiredla <bbudiredla@xxxxxxxxxxx>
Signed-off-by: Rakesh Babu <rsaladi2@xxxxxxxxxxx>
Signed-off-by: Sunil Kovvuri Goutham <sgoutham@xxxxxxxxxxx>
---
 .../marvell/octeontx2/af/rvu_debugfs.c        | 94 +++++++++++++++++++
 1 file changed, 94 insertions(+)

diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c b/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
index 1679d83cf779..205e5d203189 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
@@ -226,6 +226,96 @@ static const struct file_operations rvu_dbg_##name##_fops = { \

 static void print_nix_qsize(struct seq_file *filp, struct rvu_pfvf *pfvf);

+#define LMT_MAPTBL_ENTRY_SIZE 16
+/* Dump LMTST map table */
+static ssize_t rvu_dbg_lmtst_map_table_display(struct file *filp,
+					       char __user *buffer,
+					       size_t count, loff_t *ppos)
+{
+	struct rvu *rvu = filp->private_data;
+	u64 lmt_addr, val, tbl_base;
+	int pf, vf, num_vfs, hw_vfs;
+	void __iomem *lmt_map_base;
+	int index = 0, off = 0;
+	int bytes_not_copied;
+	int buf_size = 10240;
+	char *buf;
+
+	/* don't allow partial reads */
+	if (*ppos != 0)
+		return 0;
+
+	buf = kzalloc(buf_size, GFP_KERNEL);
+	if (!buf)
+		return -ENOSPC;
+
+	tbl_base = rvu_read64(rvu, BLKADDR_APR, APR_AF_LMT_MAP_BASE);
+
+	lmt_map_base = ioremap_wc(tbl_base, 128 * 1024);
+	if (!lmt_map_base) {
+		dev_err(rvu->dev, "Failed to setup lmt map table mapping!!\n");
+		kfree(buf);
+		return false;
+	}
+
+	off +=	scnprintf(&buf[off], buf_size - 1 - off,
+			  "\n\t\t\t\t\tLmtst Map Table Entries");
+	off +=	scnprintf(&buf[off], buf_size - 1 - off,
+			  "\n\t\t\t\t\t=======================");
+	off +=	scnprintf(&buf[off], buf_size - 1 - off, "\nPcifunc\t\t\t");
+	off +=	scnprintf(&buf[off], buf_size - 1 - off, "Table Index\t\t");
+	off +=	scnprintf(&buf[off], buf_size - 1 - off,
+			  "Lmtline Base (word 0)\t\t");
+	off +=	scnprintf(&buf[off], buf_size - 1 - off,
+			  "Lmt Map Entry (word 1)");
+	off += scnprintf(&buf[off], buf_size - 1 - off, "\n");
+	for (pf = 0; pf < rvu->hw->total_pfs; pf++) {
+		off += scnprintf(&buf[off], buf_size - 1 - off, "PF%d  \t\t\t",
+				    pf);
+
+		index = pf * rvu->hw->total_vfs * LMT_MAPTBL_ENTRY_SIZE;
+		off += scnprintf(&buf[off], buf_size - 1 - off, " 0x%llx\t\t",
+				 (tbl_base + index));
+		lmt_addr = readq(lmt_map_base + index);
+		off += scnprintf(&buf[off], buf_size - 1 - off,
+				 " 0x%016llx\t\t", lmt_addr);
+		index += 8;
+		val = readq(lmt_map_base + index);
+		off += scnprintf(&buf[off], buf_size - 1 - off, " 0x%016llx\n",
+				 val);
+		/* Reading num of VFs per PF */
+		rvu_get_pf_numvfs(rvu, pf, &num_vfs, &hw_vfs);
+		for (vf = 0; vf < num_vfs; vf++) {
+			index = (pf * rvu->hw->total_vfs * 16) +
+				((vf + 1)  * LMT_MAPTBL_ENTRY_SIZE);
+			off += scnprintf(&buf[off], buf_size - 1 - off,
+					    "PF%d:VF%d  \t\t", pf, vf);
+			off += scnprintf(&buf[off], buf_size - 1 - off,
+					 " 0x%llx\t\t", (tbl_base + index));
+			lmt_addr = readq(lmt_map_base + index);
+			off += scnprintf(&buf[off], buf_size - 1 - off,
+					 " 0x%016llx\t\t", lmt_addr);
+			index += 8;
+			val = readq(lmt_map_base + index);
+			off += scnprintf(&buf[off], buf_size - 1 - off,
+					 " 0x%016llx\n", val);
+		}
+	}
+	off +=	scnprintf(&buf[off], buf_size - 1 - off, "\n");
+
+	bytes_not_copied = copy_to_user(buffer, buf, off);
+	kfree(buf);
+
+	iounmap(lmt_map_base);
+	if (bytes_not_copied)
+		return -EFAULT;
+
+	*ppos = off;
+	return off;
+}
+
+RVU_DEBUG_FOPS(lmtst_map_table, lmtst_map_table_display, NULL);
+
 /* Dumps current provisioning status of all RVU block LFs */
 static ssize_t rvu_dbg_rsrc_attach_status(struct file *filp,
 					  char __user *buffer,
@@ -2672,6 +2762,10 @@ void rvu_dbg_init(struct rvu *rvu)
 	debugfs_create_file("rsrc_alloc", 0444, rvu->rvu_dbg.root, rvu,
 			    &rvu_dbg_rsrc_status_fops);

+	if (!is_rvu_otx2(rvu))
+		debugfs_create_file("lmtst_map_table", 0444, rvu->rvu_dbg.root,
+				    rvu, &rvu_dbg_lmtst_map_table_fops);
+
 	if (!cgx_get_cgxcnt_max())
 		goto create;

--
2.17.1