cxgb4: Add support for cim_la entry in debugfs

The CIM LA captures the embedded processor’s internal state. Optionally, it can
also trace the flow of data in and out of the embedded processor. Therefore, the
CIM LA output contains detailed information of what code the embedded processor
executed prior to the CIM LA capture.

Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 127 insertions, 2 deletions

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
index 1d3d1c590808..0f7b23f15810 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c
@@ -43,8 +43,132 @@
 #include "cxgb4_debugfs.h"
 #include "l2t.h"
 
-/* Firmware Device Log dump.
- */
+/* generic seq_file support for showing a table of size rows x width. */
+static void *seq_tab_get_idx(struct seq_tab *tb, loff_t pos)
+{
+	pos -= tb->skip_first;
+	return pos >= tb->rows ? NULL : &tb->data[pos * tb->width];
+}
+
+static void *seq_tab_start(struct seq_file *seq, loff_t *pos)
+{
+	struct seq_tab *tb = seq->private;
+
+	if (tb->skip_first && *pos == 0)
+		return SEQ_START_TOKEN;
+
+	return seq_tab_get_idx(tb, *pos);
+}
+
+static void *seq_tab_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	v = seq_tab_get_idx(seq->private, *pos + 1);
+	if (v)
+		++*pos;
+	return v;
+}
+
+static void seq_tab_stop(struct seq_file *seq, void *v)
+{
+}
+
+static int seq_tab_show(struct seq_file *seq, void *v)
+{
+	const struct seq_tab *tb = seq->private;
+
+	return tb->show(seq, v, ((char *)v - tb->data) / tb->width);
+}
+
+static const struct seq_operations seq_tab_ops = {
+	.start = seq_tab_start,
+	.next  = seq_tab_next,
+	.stop  = seq_tab_stop,
+	.show  = seq_tab_show
+};
+
+struct seq_tab *seq_open_tab(struct file *f, unsigned int rows,
+			     unsigned int width, unsigned int have_header,
+			     int (*show)(struct seq_file *seq, void *v, int i))
+{
+	struct seq_tab *p;
+
+	p = __seq_open_private(f, &seq_tab_ops, sizeof(*p) + rows * width);
+	if (p) {
+		p->show = show;
+		p->rows = rows;
+		p->width = width;
+		p->skip_first = have_header != 0;
+	}
+	return p;
+}
+
+static int cim_la_show(struct seq_file *seq, void *v, int idx)
+{
+	if (v == SEQ_START_TOKEN)
+		seq_puts(seq, "Status   Data      PC     LS0Stat  LS0Addr "
+			 "            LS0Data\n");
+	else {
+		const u32 *p = v;
+
+		seq_printf(seq,
+			   "  %02x  %x%07x %x%07x %08x %08x %08x%08x%08x%08x\n",
+			   (p[0] >> 4) & 0xff, p[0] & 0xf, p[1] >> 4,
+			   p[1] & 0xf, p[2] >> 4, p[2] & 0xf, p[3], p[4], p[5],
+			   p[6], p[7]);
+	}
+	return 0;
+}
+
+static int cim_la_show_3in1(struct seq_file *seq, void *v, int idx)
+{
+	if (v == SEQ_START_TOKEN) {
+		seq_puts(seq, "Status   Data      PC\n");
+	} else {
+		const u32 *p = v;
+
+		seq_printf(seq, "  %02x   %08x %08x\n", p[5] & 0xff, p[6],
+			   p[7]);
+		seq_printf(seq, "  %02x   %02x%06x %02x%06x\n",
+			   (p[3] >> 8) & 0xff, p[3] & 0xff, p[4] >> 8,
+			   p[4] & 0xff, p[5] >> 8);
+		seq_printf(seq, "  %02x   %x%07x %x%07x\n", (p[0] >> 4) & 0xff,
+			   p[0] & 0xf, p[1] >> 4, p[1] & 0xf, p[2] >> 4);
+	}
+	return 0;
+}
+
+static int cim_la_open(struct inode *inode, struct file *file)
+{
+	int ret;
+	unsigned int cfg;
+	struct seq_tab *p;
+	struct adapter *adap = inode->i_private;
+
+	ret = t4_cim_read(adap, UP_UP_DBG_LA_CFG_A, 1, &cfg);
+	if (ret)
+		return ret;
+
+	p = seq_open_tab(file, adap->params.cim_la_size / 8, 8 * sizeof(u32), 1,
+			 cfg & UPDBGLACAPTPCONLY_F ?
+			 cim_la_show_3in1 : cim_la_show);
+	if (!p)
+		return -ENOMEM;
+
+	ret = t4_cim_read_la(adap, (u32 *)p->data, NULL);
+	if (ret)
+		seq_release_private(inode, file);
+	return ret;
+}
+
+static const struct file_operations cim_la_fops = {
+	.owner   = THIS_MODULE,
+	.open    = cim_la_open,
+	.read    = seq_read,
+	.llseek  = seq_lseek,
+	.release = seq_release_private
+};
+
+/* Firmware Device Log dump. */
 static const char * const devlog_level_strings[] = {
 	[FW_DEVLOG_LEVEL_EMERG]		= "EMERG",
 	[FW_DEVLOG_LEVEL_CRIT]		= "CRIT",
@@ -318,6 +442,7 @@ int t4_setup_debugfs(struct adapter *adap)
 	u32 size;
 
 	static struct t4_debugfs_entry t4_debugfs_files[] = {
+		{ "cim_la", &cim_la_fops, S_IRUSR, 0 },
 		{ "devlog", &devlog_fops, S_IRUSR, 0 },
 		{ "l2t", &t4_l2t_fops, S_IRUSR, 0},
 	};