[12/15] habanalabs/gaudi: add debugfs entries for the NIC

diff --git a/Documentation/ABI/testing/debugfs-driver-habanalabs b/Documentation/ABI/testing/debugfs-driver-habanalabs
index 2e9ae311e02d..8fca02b92a80 100644
--- a/Documentation/ABI/testing/debugfs-driver-habanalabs
+++ b/Documentation/ABI/testing/debugfs-driver-habanalabs
@@ -176,3 +176,72 @@  KernelVersion:  5.6
 Contact:        oded.gabbay@gmail.com
 Description:    Sets the stop-on_error option for the device engines. Value of
                 "0" is for disable, otherwise enable.
+
+What:           /sys/kernel/debug/habanalabs/hl<n>/nic_mac_loopback
+Date:           Nov 2020
+KernelVersion:  5.10
+Contact:        oshpigelman@habana.ai
+Description:    Allows the root user to disable/enable MAC loopback for Gaudi
+                NIC ports. The ports will function as if a physical loopback
+                transceiver was connected. A bitmask should be provided where
+                each bit represents a port, up to 20 bits.
+                Known issues for this mode:
+                1. Odd ports PHY is not stopped so the peer's odd ports will get
+                PCS link.
+                2. Might cause an interrupt storm due to high B/W.
+
+What:           /sys/kernel/debug/habanalabs/hl<n>/nic_ports_status
+Date:           Nov 2020
+KernelVersion:  5.10
+Contact:        oshpigelman@habana.ai
+Description:    Displays a summary the PC link state of all Gaudi NIC ports.
+
+What:           /sys/kernel/debug/habanalabs/hl<n>/nic_pcs_fail_time_frame
+Date:           Nov 2020
+KernelVersion:  5.10
+Contact:        oshpigelman@habana.ai
+Description:    Allows the root user to set the used time frame in seconds for
+                detecting a loose PCS link of a Gaudi NIC port. We count how
+                many PCS link failures occurred in a time frame up to a
+                threshold which will cause PHY reconfiguration for getting a new
+                PCS link.
+
+What:           /sys/kernel/debug/habanalabs/hl<n>/nic_pcs_fail_threshold
+Date:           Nov 2020
+KernelVersion:  5.10
+Contact:        oshpigelman@habana.ai
+Description:    Allows the root user to set the used threshold for detecting a
+                loose PCS link of a Gaudi NIC port. We count how many PCS link
+                failures occurred in a time frame up to the threshold which will
+                cause PHY reconfiguration for getting a new PCS link.
+
+What:           /sys/kernel/debug/habanalabs/hl<n>/nic_pam4_tx_taps
+Date:           Nov 2020
+KernelVersion:  5.10
+Contact:        oshpigelman@habana.ai
+Description:    Allows the root user to set the PAM4 Tx taps for Gaudi NIC port
+                lanes. The lanes indices are 0-39.
+                Acceptable input string form:
+                <lane> <tx_pre2> <tx_pre1> <tx_main> <tx_post1> <tx_post2>.
+
+What:           /sys/kernel/debug/habanalabs/hl<n>/nic_polarity
+Date:           Nov 2020
+KernelVersion:  5.10
+Contact:        oshpigelman@habana.ai
+Description:    Allows the root user to set the polarity for Gaudi NIC port
+                lanes. The lanes indices are 0-39.
+                Acceptable input string form: <lane> <pol_tx> <pol_rx>.
+
+What:           /sys/kernel/debug/habanalabs/hl<n>/nic_check_link
+Date:           Nov 2020
+KernelVersion:  5.10
+Contact:        oshpigelman@habana.ai
+Description:    Sets the PCS link periodic check for all Gaudi NIC ports. Value
+                of "0" is for disable, otherwise enable.
+
+What:           /sys/kernel/debug/habanalabs/hl<n>/nic_phy_auto_neg_lpbk
+Date:           Nov 2020
+KernelVersion:  5.10
+Contact:        oshpigelman@habana.ai
+Description:    Sets the PHY Autoneg loopback support for all Gaudi NIC ports.
+                Value of "0" is for disable, otherwise enable.
diff --git a/drivers/misc/habanalabs/gaudi/Makefile b/drivers/misc/habanalabs/gaudi/Makefile
index c5143cf6f025..437b21e54c95 100644
--- a/drivers/misc/habanalabs/gaudi/Makefile
+++ b/drivers/misc/habanalabs/gaudi/Makefile
@@ -2,4 +2,5 @@ 
 HL_GAUDI_FILES := gaudi/gaudi.o gaudi/gaudi_hwmgr.o gaudi/gaudi_security.o \
 	gaudi/gaudi_coresight.o
 
-HL_GAUDI_FILES += gaudi/gaudi_nic.o gaudi/gaudi_phy.o
+HL_GAUDI_FILES += gaudi/gaudi_nic.o gaudi/gaudi_phy.o \
+	gaudi/gaudi_nic_debugfs.o
diff --git a/drivers/misc/habanalabs/gaudi/gaudi_nic.c b/drivers/misc/habanalabs/gaudi/gaudi_nic.c
index 41789f7ed32e..a73635a4c44b 100644
--- a/drivers/misc/habanalabs/gaudi/gaudi_nic.c
+++ b/drivers/misc/habanalabs/gaudi/gaudi_nic.c
@@ -3025,6 +3025,8 @@  int gaudi_nic_ports_init(struct hl_device *hdev)
 			}
 		}
 
+	gaudi_nic_debugfs_init(hdev);
+
 	gaudi->hw_cap_initialized |= HW_CAP_NIC_DRV;
 
 	return 0;
diff --git a/drivers/misc/habanalabs/gaudi/gaudi_nic_debugfs.c b/drivers/misc/habanalabs/gaudi/gaudi_nic_debugfs.c
new file mode 100644
index 000000000000..2e99d2683512
--- /dev/null
+++ b/drivers/misc/habanalabs/gaudi/gaudi_nic_debugfs.c
@@ -0,0 +1,402 @@ 
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Copyright 2018-2020 HabanaLabs, Ltd.
+ * All Rights Reserved.
+ */
+
+#include "gaudi_nic.h"
+#include <linux/debugfs.h>
+#include <linux/nospec.h>
+
+#ifdef CONFIG_DEBUG_FS
+
+#define POLARITY_KBUF_SIZE	8
+#define TX_TAPS_KBUF_SIZE	25
+
+static ssize_t debugfs_pam4_tx_taps_write(struct file *f,
+						const char __user *buf,
+						size_t count, loff_t *ppos)
+{
+	struct hl_device *hdev = file_inode(f)->i_private;
+	struct gaudi_device *gaudi = hdev->asic_specific;
+	char kbuf[TX_TAPS_KBUF_SIZE];
+	char *c1, *c2;
+	ssize_t rc;
+	u32 lane;
+	s32 tx_pre2, tx_pre1, tx_main, tx_post1, tx_post2;
+	s32 *taps;
+
+	if (count > sizeof(kbuf) - 1)
+		goto err;
+	if (copy_from_user(kbuf, buf, count))
+		goto err;
+	kbuf[count] = '\0';
+
+	c1 = kbuf;
+	c2 = strchr(c1, ' ');
+	if (!c2)
+		goto err;
+	*c2 = '\0';
+
+	rc = kstrtou32(c1, 10, &lane);
+	if (rc)
+		goto err;
+
+	if (lane >= NIC_MAX_NUM_OF_LANES) {
+		dev_err(hdev->dev, "lane max value is %d\n",
+			NIC_MAX_NUM_OF_LANES - 1);
+		return -EINVAL;
+	}
+
+	/* Turn off speculation due to Spectre vulnerability */
+	lane = array_index_nospec(lane, NIC_MAX_NUM_OF_LANES);
+
+	c1 = c2 + 1;
+
+	c2 = strchr(c1, ' ');
+	if (!c2)
+		goto err;
+	*c2 = '\0';
+
+	rc = kstrtos32(c1, 10, &tx_pre2);
+	if (rc)
+		goto err;
+
+	c1 = c2 + 1;
+
+	c2 = strchr(c1, ' ');
+	if (!c2)
+		goto err;
+	*c2 = '\0';
+
+	rc = kstrtos32(c1, 10, &tx_pre1);
+	if (rc)
+		goto err;
+
+	c1 = c2 + 1;
+
+	c2 = strchr(c1, ' ');
+	if (!c2)
+		goto err;
+	*c2 = '\0';
+
+	rc = kstrtos32(c1, 10, &tx_main);
+	if (rc)
+		goto err;
+
+	c1 = c2 + 1;
+
+	c2 = strchr(c1, ' ');
+	if (!c2)
+		goto err;
+	*c2 = '\0';
+
+	rc = kstrtos32(c1, 10, &tx_post1);
+	if (rc)
+		goto err;
+
+	c1 = c2 + 1;
+
+	rc = kstrtos32(c1, 10, &tx_post2);
+	if (rc)
+		goto err;
+
+	taps = gaudi->nic_pam4_tx_taps[lane].taps;
+	taps[0] = tx_pre2;
+	taps[1] = tx_pre1;
+	taps[2] = tx_main;
+	taps[3] = tx_post1;
+	taps[4] = tx_post2;
+
+	return count;
+err:
+	dev_err(hdev->dev,
+		"usage: echo <lane> <tx_pre2> <tx_pre1> <tx_main> <tx_post1> <tx_post2> > nic_pam4_tx_taps\n");
+
+	return -EINVAL;
+}
+
+static const struct file_operations debugfs_pam4_tx_taps_fops = {
+	.owner = THIS_MODULE,
+	.write = debugfs_pam4_tx_taps_write,
+};
+
+static ssize_t debugfs_polarity_write(struct file *f, const char __user *buf,
+					size_t count, loff_t *ppos)
+{
+	struct hl_device *hdev = file_inode(f)->i_private;
+	struct gaudi_device *gaudi = hdev->asic_specific;
+	struct cpucp_nic_info *nic_info = &hdev->asic_prop.cpucp_nic_info;
+	char kbuf[POLARITY_KBUF_SIZE];
+	char *c1, *c2;
+	ssize_t rc;
+	u64 val;
+	u32 lane;
+	u8 pol_tx, pol_rx;
+
+	if (count > sizeof(kbuf) - 1)
+		goto err;
+	if (copy_from_user(kbuf, buf, count))
+		goto err;
+	kbuf[count] = '\0';
+
+	c1 = kbuf;
+	c2 = strchr(c1, ' ');
+	if (!c2)
+		goto err;
+	*c2 = '\0';
+
+	rc = kstrtou32(c1, 10, &lane);
+	if (rc)
+		goto err;
+
+	if (lane >= NIC_MAX_NUM_OF_LANES) {
+		dev_err(hdev->dev, "lane max value is %d\n",
+			NIC_MAX_NUM_OF_LANES - 1);
+		return -EINVAL;
+	}
+
+	c1 = c2 + 1;
+
+	c2 = strchr(c1, ' ');
+	if (!c2)
+		goto err;
+	*c2 = '\0';
+
+	rc = kstrtou8(c1, 10, &pol_tx);
+	if (rc)
+		goto err;
+
+	c1 = c2 + 1;
+
+	rc = kstrtou8(c1, 10, &pol_rx);
+	if (rc)
+		goto err;
+
+	if ((pol_tx & ~1) || (pol_rx & ~1)) {
+		dev_err(hdev->dev, "pol_tx and pol_rx should be 0 or 1\n");
+		goto err;
+	}
+
+	val = le64_to_cpu(nic_info->pol_tx_mask[0]);
+	val &= ~BIT_ULL(lane);
+	val |= ((u64) pol_tx) << lane;
+	nic_info->pol_tx_mask[0] = cpu_to_le64(val);
+
+	val = le64_to_cpu(nic_info->pol_rx_mask[0]);
+	val &= ~BIT_ULL(lane);
+	val |= ((u64) pol_rx) << lane;
+	nic_info->pol_rx_mask[0] = cpu_to_le64(val);
+
+	gaudi->nic_use_fw_polarity = true;
+
+	return count;
+err:
+	dev_err(hdev->dev,
+		"usage: echo <lane> <pol_tx> <pol_rx> > nic_polarity\n");
+
+	return -EINVAL;
+}
+
+static const struct file_operations debugfs_polarity_fops = {
+	.owner = THIS_MODULE,
+	.write = debugfs_polarity_write,
+};
+
+static ssize_t debugfs_ports_status_read(struct file *f, char __user *buf,
+					size_t count, loff_t *ppos)
+{
+	struct hl_device *hdev = file_inode(f)->i_private;
+	struct gaudi_device *gaudi = hdev->asic_specific;
+	char tmp_buf[512] = {0};
+	ssize_t rc;
+	int i, up_cnt = 0, down_cnt = 0;
+
+	if (*ppos)
+		return 0;
+
+	for (i = 0 ; i < NIC_NUMBER_OF_PORTS ; i++)
+		if ((hdev->nic_ports_mask & BIT(i))) {
+			if (gaudi->nic_devices[i].active)
+				up_cnt++;
+			else
+				down_cnt++;
+		}
+
+	if (up_cnt) {
+		sprintf(tmp_buf, "%d ports up (", up_cnt);
+
+		for (i = 0 ; i < NIC_NUMBER_OF_PORTS ; i++)
+			if ((hdev->nic_ports_mask & BIT(i)) &&
+				gaudi->nic_devices[i].active)
+				sprintf(tmp_buf + strlen(tmp_buf), "%d, ", i);
+
+		sprintf(tmp_buf + strlen(tmp_buf) - 2, ")");
+	}
+
+	if (down_cnt) {
+		if (up_cnt)
+			sprintf(tmp_buf + strlen(tmp_buf), "\n");
+
+		sprintf(tmp_buf + strlen(tmp_buf), "%d ports down (", down_cnt);
+
+		for (i = 0 ; i < NIC_NUMBER_OF_PORTS ; i++)
+			if ((hdev->nic_ports_mask & BIT(i)) &&
+				!gaudi->nic_devices[i].active)
+				sprintf(tmp_buf + strlen(tmp_buf), "%d, ", i);
+
+		sprintf(tmp_buf + strlen(tmp_buf) - 2, ")");
+	}
+
+	sprintf(tmp_buf + strlen(tmp_buf), "\n");
+
+	rc = simple_read_from_buffer(buf, strlen(tmp_buf) + 1, ppos, tmp_buf,
+					strlen(tmp_buf) + 1);
+
+	return rc;
+}
+
+static const struct file_operations debugfs_ports_status_fops = {
+	.owner = THIS_MODULE,
+	.read = debugfs_ports_status_read,
+};
+
+#define NIC_DEBUGFS(X, fmt, do_reset) \
+static ssize_t debugfs_##X##_read(struct file *f, \
+					char __user *buf, \
+					size_t count, \
+					loff_t *ppos) \
+{ \
+	struct hl_device *hdev = file_inode(f)->i_private; \
+	struct gaudi_device *gaudi = hdev->asic_specific; \
+	char tmp_buf[32]; \
+	ssize_t rc; \
+\
+	if (*ppos) \
+		return 0; \
+\
+	sprintf(tmp_buf, fmt "\n", gaudi->nic_##X); \
+	rc = simple_read_from_buffer(buf, strlen(tmp_buf) + 1, ppos, tmp_buf, \
+			strlen(tmp_buf) + 1); \
+\
+	return rc; \
+} \
+\
+static ssize_t debugfs_##X##_write(struct file *f, \
+					const char __user *buf, \
+					size_t count, \
+					loff_t *ppos) \
+{ \
+	struct hl_device *hdev = file_inode(f)->i_private; \
+	struct gaudi_device *gaudi = hdev->asic_specific; \
+	u64 val, base; \
+	ssize_t rc; \
+\
+	if (!strcmp(fmt, "%d")) \
+		base = 10; \
+	else \
+		base = 16; \
+\
+	rc = kstrtoull_from_user(buf, count, base, &val); \
+	if (rc) \
+		return rc; \
+\
+	if (val == gaudi->nic_##X) \
+		return count; \
+\
+	if (do_reset && gaudi->nic_debugfs_reset) { \
+		gaudi->nic_##X = val; \
+		hl_device_reset(hdev, true, false); \
+		ssleep(HL_PENDING_RESET_PER_SEC); \
+		return count; \
+	} \
+\
+	dev_info(hdev->dev, "NIC reset for %s started\n", __stringify(X)); \
+\
+	rc = gaudi_nic_hard_reset_prepare(hdev); \
+	if (rc) \
+		return rc; \
+\
+	gaudi_nic_stop(hdev); \
+\
+	/* must do this so the ports will be reopened */ \
+	gaudi->hw_cap_initialized &= ~HW_CAP_NIC_DRV; \
+\
+	gaudi->nic_##X = val; \
+\
+	gaudi_nic_ports_reopen(hdev); \
+\
+	dev_info(hdev->dev, "NIC reset for %s finished\n", __stringify(X)); \
+\
+	return count; \
+} \
+\
+static const struct file_operations debugfs_##X##_fops = { \
+	.owner = THIS_MODULE, \
+	.read = debugfs_##X##_read, \
+	.write = debugfs_##X##_write, \
+}
+
+NIC_DEBUGFS(mac_loopback, "0x%llx", true);
+NIC_DEBUGFS(pcs_fail_time_frame, "%d", false);
+NIC_DEBUGFS(pcs_fail_threshold, "%d", false);
+
+void gaudi_nic_debugfs_init(struct hl_device *hdev)
+{
+	struct gaudi_device *gaudi = hdev->asic_specific;
+
+	debugfs_create_file("nic_mac_loopback",
+				0644,
+				hdev->hl_debugfs.root,
+				hdev,
+				&debugfs_mac_loopback_fops);
+
+	debugfs_create_file("nic_ports_status",
+				0444,
+				hdev->hl_debugfs.root,
+				hdev,
+				&debugfs_ports_status_fops);
+
+	debugfs_create_file("nic_pcs_fail_time_frame",
+				0644,
+				hdev->hl_debugfs.root,
+				hdev,
+				&debugfs_pcs_fail_time_frame_fops);
+
+	debugfs_create_file("nic_pcs_fail_threshold",
+				0644,
+				hdev->hl_debugfs.root,
+				hdev,
+				&debugfs_pcs_fail_threshold_fops);
+
+	debugfs_create_file("nic_pam4_tx_taps",
+				0444,
+				hdev->hl_debugfs.root,
+				hdev,
+				&debugfs_pam4_tx_taps_fops);
+
+	debugfs_create_file("nic_polarity",
+				0444,
+				hdev->hl_debugfs.root,
+				hdev,
+				&debugfs_polarity_fops);
+
+	debugfs_create_u8("nic_check_link",
+				0644,
+				hdev->hl_debugfs.root,
+				&gaudi->nic_check_link);
+
+	debugfs_create_u8("nic_phy_auto_neg_lpbk",
+				0644,
+				hdev->hl_debugfs.root,
+				&gaudi->nic_phy_auto_neg_lpbk);
+}
+
+#else
+
+void gaudi_nic_debugfs_init(struct hl_device *hdev)
+{
+}
+
+#endif /* CONFIG_DEBUG_FS */