// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 1999 - 2018 Intel Corporation. */

#include <linux/debugfs.h>
#include <linux/module.h>

#include "ixgbe.h"
#include "ixgbe_phy.h"

static struct dentry *ixgbe_dbg_root;

static char ixgbe_dbg_reg_ops_buf[256] = "";

static ssize_t ixgbe_dbg_common_ops_read(struct file *filp, char __user *buffer,
					 size_t count, loff_t *ppos,
					 char *dbg_buf)
{
	struct ixgbe_adapter *adapter = filp->private_data;
	char *buf;
	int len;

	/* don't allow partial reads */
	if (*ppos != 0)
		return 0;

	buf = kasprintf(GFP_KERNEL, "%s: %s\n",
			adapter->netdev->name, dbg_buf);
	if (!buf)
		return -ENOMEM;

	if (count < strlen(buf)) {
		kfree(buf);
		return -ENOSPC;
	}

	len = simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf));

	kfree(buf);
	return len;
}

/**
 * ixgbe_dbg_reg_ops_read - read for reg_ops datum
 * @filp: the opened file
 * @buffer: where to write the data for the user to read
 * @count: the size of the user's buffer
 * @ppos: file position offset
 **/
static ssize_t ixgbe_dbg_reg_ops_read(struct file *filp, char __user *buffer,
				      size_t count, loff_t *ppos)
{
	return ixgbe_dbg_common_ops_read(filp, buffer, count, ppos,
					 ixgbe_dbg_reg_ops_buf);
}

/**
 * ixgbe_dbg_reg_ops_write - write into reg_ops datum
 * @filp: the opened file
 * @buffer: where to find the user's data
 * @count: the length of the user's data
 * @ppos: file position offset
 **/
static ssize_t ixgbe_dbg_reg_ops_write(struct file *filp,
				     const char __user *buffer,
				     size_t count, loff_t *ppos)
{
	struct ixgbe_adapter *adapter = filp->private_data;
	int len;

	/* don't allow partial writes */
	if (*ppos != 0)
		return 0;
	if (count >= sizeof(ixgbe_dbg_reg_ops_buf))
		return -ENOSPC;

	len = simple_write_to_buffer(ixgbe_dbg_reg_ops_buf,
				     sizeof(ixgbe_dbg_reg_ops_buf)-1,
				     ppos,
				     buffer,
				     count);
	if (len < 0)
		return len;

	ixgbe_dbg_reg_ops_buf[len] = '\0';

	if (strncmp(ixgbe_dbg_reg_ops_buf, "write", 5) == 0) {
		u32 reg, value;
		int cnt;
		cnt = sscanf(&ixgbe_dbg_reg_ops_buf[5], "%x %x", &reg, &value);
		if (cnt == 2) {
			IXGBE_WRITE_REG(&adapter->hw, reg, value);
			value = IXGBE_READ_REG(&adapter->hw, reg);
			e_dev_info("write: 0x%08x = 0x%08x\n", reg, value);
		} else {
			e_dev_info("write <reg> <value>\n");
		}
	} else if (strncmp(ixgbe_dbg_reg_ops_buf, "read", 4) == 0) {
		u32 reg, value;
		int cnt;
		cnt = sscanf(&ixgbe_dbg_reg_ops_buf[4], "%x", &reg);
		if (cnt == 1) {
			value = IXGBE_READ_REG(&adapter->hw, reg);
			snprintf(ixgbe_dbg_reg_ops_buf,
				 sizeof(ixgbe_dbg_reg_ops_buf),
				 "0x%08x = 0x%08x", reg, value);
		} else {
			e_dev_info("read <reg>\n");
		}
	} else {
		e_dev_info("Unknown command %s\n", ixgbe_dbg_reg_ops_buf);
		e_dev_info("Available commands:\n");
		e_dev_info("   read <reg>\n");
		e_dev_info("   write <reg> <value>\n");
	}
	return count;
}

static const struct file_operations ixgbe_dbg_reg_ops_fops = {
	.owner = THIS_MODULE,
	.open = simple_open,
	.read =  ixgbe_dbg_reg_ops_read,
	.write = ixgbe_dbg_reg_ops_write,
};

static char ixgbe_dbg_netdev_ops_buf[256] = "";

/**
 * ixgbe_dbg_netdev_ops_read - read for netdev_ops datum
 * @filp: the opened file
 * @buffer: where to write the data for the user to read
 * @count: the size of the user's buffer
 * @ppos: file position offset
 **/
static ssize_t ixgbe_dbg_netdev_ops_read(struct file *filp, char __user *buffer,
					 size_t count, loff_t *ppos)
{
	return ixgbe_dbg_common_ops_read(filp, buffer, count, ppos,
					 ixgbe_dbg_netdev_ops_buf);
}

/**
 * ixgbe_dbg_netdev_ops_write - write into netdev_ops datum
 * @filp: the opened file
 * @buffer: where to find the user's data
 * @count: the length of the user's data
 * @ppos: file position offset
 **/
static ssize_t ixgbe_dbg_netdev_ops_write(struct file *filp,
					  const char __user *buffer,
					  size_t count, loff_t *ppos)
{
	struct ixgbe_adapter *adapter = filp->private_data;
	int len;

	/* don't allow partial writes */
	if (*ppos != 0)
		return 0;
	if (count >= sizeof(ixgbe_dbg_netdev_ops_buf))
		return -ENOSPC;

	len = simple_write_to_buffer(ixgbe_dbg_netdev_ops_buf,
				     sizeof(ixgbe_dbg_netdev_ops_buf)-1,
				     ppos,
				     buffer,
				     count);
	if (len < 0)
		return len;

	ixgbe_dbg_netdev_ops_buf[len] = '\0';

	if (strncmp(ixgbe_dbg_netdev_ops_buf, "tx_timeout", 10) == 0) {
		/* TX Queue number below is wrong, but ixgbe does not use it */
		adapter->netdev->netdev_ops->ndo_tx_timeout(adapter->netdev,
							    UINT_MAX);
		e_dev_info("tx_timeout called\n");
	} else {
		e_dev_info("Unknown command: %s\n", ixgbe_dbg_netdev_ops_buf);
		e_dev_info("Available commands:\n");
		e_dev_info("    tx_timeout\n");
	}
	return count;
}

static const struct file_operations ixgbe_dbg_netdev_ops_fops = {
	.owner = THIS_MODULE,
	.open = simple_open,
	.read = ixgbe_dbg_netdev_ops_read,
	.write = ixgbe_dbg_netdev_ops_write,
};

#define IXGBE_SFF_I2C_MAX 32

struct ixgbe_sff_i2c_ctx {
	struct ixgbe_adapter *adapter;
	int resp_len;
	char resp[IXGBE_SFF_I2C_MAX * 3 + 16];
};

static int ixgbe_dbg_sff_i2c_open(struct inode *inode, struct file *filp)
{
	struct ixgbe_sff_i2c_ctx *ctx;

	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
	if (!ctx)
		return -ENOMEM;
	ctx->adapter = inode->i_private;
	filp->private_data = ctx;
	return 0;
}

static int ixgbe_dbg_sff_i2c_release(struct inode *inode, struct file *filp)
{
	kfree(filp->private_data);
	return 0;
}

static ssize_t ixgbe_dbg_sff_i2c_write(struct file *filp,
				       const char __user *ubuf,
				       size_t count, loff_t *ppos)
{
	struct ixgbe_sff_i2c_ctx *ctx = filp->private_data;
	struct ixgbe_hw *hw = &ctx->adapter->hw;
	u8 data[IXGBE_SFF_I2C_MAX];
	u8 wdata[IXGBE_SFF_I2C_MAX];
	char cmd[160];
	unsigned int addr, raddr, delay, n, wn, v;
	int status, off, consumed, i;
	char op;

	if (*ppos != 0 || count >= sizeof(cmd))
		return -EINVAL;
	if (copy_from_user(cmd, ubuf, count))
		return -EFAULT;
	cmd[count] = '\0';

	if (sscanf(cmd, " %c %x %n", &op, &addr, &off) < 2)
		return -EINVAL;

	if (op == 'r') {
		if (sscanf(cmd + off, "%x", &n) != 1 || n < 1 ||
		    n > IXGBE_SFF_I2C_MAX)
			return -EINVAL;
		status = ixgbe_i2c_raw_read(hw, addr, data, n);
	} else if (op == 'w') {
		n = 0;
		while (n < IXGBE_SFF_I2C_MAX &&
		       sscanf(cmd + off, "%x%n", &v, &consumed) == 1) {
			data[n++] = v;
			off += consumed;
		}
		status = ixgbe_i2c_raw_write(hw, addr, data, n);
	} else if (op == 'x') {
		if (sscanf(cmd + off, "%x %u %x %n", &raddr, &delay, &n,
			   &consumed) < 3)
			return -EINVAL;
		off += consumed;
		if (n > IXGBE_SFF_I2C_MAX || delay > 50000)
			return -EINVAL;
		wn = 0;
		while (wn < IXGBE_SFF_I2C_MAX &&
		       sscanf(cmd + off, "%x%n", &v, &consumed) == 1) {
			wdata[wn++] = v;
			off += consumed;
		}
		status = ixgbe_i2c_raw_xfer(hw, addr, wdata, wn, delay,
					    raddr, data, n);
	} else {
		return -EINVAL;
	}

	if (status) {
		ctx->resp_len = scnprintf(ctx->resp, sizeof(ctx->resp),
					  "err %d\n", status);
	} else if (op == 'r' || (op == 'x' && n)) {
		off = scnprintf(ctx->resp, sizeof(ctx->resp), "ok");
		for (i = 0; i < n; i++)
			off += scnprintf(ctx->resp + off,
					 sizeof(ctx->resp) - off,
					 " %02x", data[i]);
		off += scnprintf(ctx->resp + off, sizeof(ctx->resp) - off,
				 "\n");
		ctx->resp_len = off;
	} else {
		ctx->resp_len = scnprintf(ctx->resp, sizeof(ctx->resp), "ok\n");
	}

	*ppos = 0;
	return count;
}

static ssize_t ixgbe_dbg_sff_i2c_read(struct file *filp, char __user *ubuf,
				      size_t count, loff_t *ppos)
{
	struct ixgbe_sff_i2c_ctx *ctx = filp->private_data;

	return simple_read_from_buffer(ubuf, count, ppos, ctx->resp,
				       ctx->resp_len);
}

static const struct file_operations ixgbe_dbg_sff_i2c_fops = {
	.owner = THIS_MODULE,
	.open = ixgbe_dbg_sff_i2c_open,
	.release = ixgbe_dbg_sff_i2c_release,
	.read = ixgbe_dbg_sff_i2c_read,
	.write = ixgbe_dbg_sff_i2c_write,
};

/* In-kernel timestamp-latch experiments. The BAR is unmappable from userspace
 * under IO_STRICT_DEVMEM, and the latch re-arms on RXSTMPH read, so the tight
 * poll+drain loop lives here; userspace supplies the traffic concurrently.
 */
struct ixgbe_ts_bench_ctx {
	struct ixgbe_adapter *adapter;
	char resp[512];
	int resp_len;
};

static int ixgbe_dbg_ts_bench_open(struct inode *inode, struct file *filp)
{
	struct ixgbe_ts_bench_ctx *ctx;

	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
	if (!ctx)
		return -ENOMEM;
	ctx->adapter = inode->i_private;
	filp->private_data = ctx;
	return 0;
}

static int ixgbe_dbg_ts_bench_release(struct inode *inode, struct file *filp)
{
	kfree(filp->private_data);
	return 0;
}

/* Wait up to ms for TSYNCRXCTL.VALID; return 1 if it armed. */
static int ixgbe_ts_wait_valid(struct ixgbe_hw *hw, unsigned int ms)
{
	unsigned long end = jiffies + msecs_to_jiffies(ms);

	do {
		if (IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL) &
		    IXGBE_TSYNCRXCTL_VALID)
			return 1;
		cpu_relax();
		cond_resched();
	} while (time_before(jiffies, end));
	return 0;
}

static ssize_t ixgbe_dbg_ts_bench_write(struct file *filp,
					const char __user *ubuf,
					size_t count, loff_t *ppos)
{
	struct ixgbe_ts_bench_ctx *ctx = filp->private_data;
	struct ixgbe_hw *hw = &ctx->adapter->hw;
	char cmd[64];
	unsigned int arg;
	u32 save_ctl, save_etqf3;
	int off;
	char op[16];

	if (*ppos != 0 || count >= sizeof(cmd))
		return -EINVAL;
	if (copy_from_user(cmd, ubuf, count))
		return -EFAULT;
	cmd[count] = '\0';

	if (sscanf(cmd, "%15s %n", op, &off) < 1)
		return -EINVAL;

	save_ctl = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
	save_etqf3 = IXGBE_READ_REG(hw, IXGBE_ETQF(IXGBE_ETQF_FILTER_1588));
	IXGBE_READ_REG(hw, IXGBE_RXSTMPH); /* drain any stale latch */

	if (strcmp(op, "arm") == 0) {
		/* arm <ctl>: write raw ctl, poll for a raw-frame latch. */
		if (sscanf(cmd + off, "%x", &arg) != 1)
			return -EINVAL;
		IXGBE_WRITE_REG(hw, IXGBE_TSYNCRXCTL, arg);
		{
			u32 rb = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
			int valid = ixgbe_ts_wait_valid(hw, 600);

			ctx->resp_len = scnprintf(ctx->resp, sizeof(ctx->resp),
				"ctl_wrote=%08x ctl_readback=%08x valid=%d STMPL=%08x STMPH=%08x SATRL=%08x SATRH=%08x\n",
				arg, rb, valid,
				IXGBE_READ_REG(hw, IXGBE_RXSTMPL),
				IXGBE_READ_REG(hw, IXGBE_RXSTMPH),
				IXGBE_READ_REG(hw, IXGBE_RXSATRL),
				IXGBE_READ_REG(hw, IXGBE_RXSATRH));
		}
	} else if (strcmp(op, "control") == 0) {
		/* Positive control: L2 PTPv2 event latch via ETQF slot 3. */
		IXGBE_WRITE_REG(hw, IXGBE_ETQF(IXGBE_ETQF_FILTER_1588),
				IXGBE_ETQF_1588 | IXGBE_ETQF_FILTER_EN |
				ETH_P_1588);
		IXGBE_WRITE_REG(hw, IXGBE_TSYNCRXCTL, IXGBE_TSYNCRXCTL_ENABLED |
				IXGBE_TSYNCRXCTL_TYPE_L2_V2);
		{
			int valid = ixgbe_ts_wait_valid(hw, 600);
			u32 satrh = IXGBE_READ_REG(hw, IXGBE_RXSATRH);

			ctx->resp_len = scnprintf(ctx->resp, sizeof(ctx->resp),
				"valid=%d STMPL=%08x STMPH=%08x SATRL=%08x SATRH=%08x satr_seq=%04x SYSTIML=%08x SYSTIMH=%08x\n",
				valid,
				IXGBE_READ_REG(hw, IXGBE_RXSTMPL),
				IXGBE_READ_REG(hw, IXGBE_RXSTMPH),
				IXGBE_READ_REG(hw, IXGBE_RXSATRL),
				satrh, swab16(satrh >> 16),
				IXGBE_READ_REG(hw, IXGBE_SYSTIML),
				IXGBE_READ_REG(hw, IXGBE_SYSTIMH));
		}
	} else if (strcmp(op, "latchrate") == 0) {
		/* latchrate <ms>: count serviced latches over the window while
		 * userspace floods L2 PTP frames. Re-arm by reading RXSTMPH.
		 */
		unsigned long end;
		u32 captured = 0, distinct = 0;
		unsigned long *seen;

		if (sscanf(cmd + off, "%u", &arg) != 1 || arg == 0 || arg > 10000)
			return -EINVAL;
		seen = kcalloc(BITS_TO_LONGS(65536), sizeof(long), GFP_KERNEL);
		if (!seen)
			return -ENOMEM;
		IXGBE_WRITE_REG(hw, IXGBE_ETQF(IXGBE_ETQF_FILTER_1588),
				IXGBE_ETQF_1588 | IXGBE_ETQF_FILTER_EN |
				ETH_P_1588);
		IXGBE_WRITE_REG(hw, IXGBE_TSYNCRXCTL, IXGBE_TSYNCRXCTL_ENABLED |
				IXGBE_TSYNCRXCTL_TYPE_L2_V2);
		end = jiffies + msecs_to_jiffies(arg);
		do {
			if (IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL) &
			    IXGBE_TSYNCRXCTL_VALID) {
				u32 seq = IXGBE_READ_REG(hw, IXGBE_RXSATRH) >>
					  16;
				IXGBE_READ_REG(hw, IXGBE_RXSTMPL);
				IXGBE_READ_REG(hw, IXGBE_RXSTMPH); /* re-arm */
				captured++;
				if (!__test_and_set_bit(seq, seen))
					distinct++;
			}
			cpu_relax();
			cond_resched();
		} while (time_before(jiffies, end));
		ctx->resp_len = scnprintf(ctx->resp, sizeof(ctx->resp),
			"window_ms=%u captured=%u distinct_seq=%u rate=%u/s\n",
			arg, captured, distinct, captured * 1000 / arg);
		kfree(seen);
	} else {
		return -EINVAL;
	}

	IXGBE_WRITE_REG(hw, IXGBE_TSYNCRXCTL, save_ctl);
	IXGBE_WRITE_REG(hw, IXGBE_ETQF(IXGBE_ETQF_FILTER_1588), save_etqf3);
	*ppos = 0;
	return count;
}

static ssize_t ixgbe_dbg_ts_bench_read(struct file *filp, char __user *ubuf,
				       size_t count, loff_t *ppos)
{
	struct ixgbe_ts_bench_ctx *ctx = filp->private_data;

	return simple_read_from_buffer(ubuf, count, ppos, ctx->resp,
				       ctx->resp_len);
}

static const struct file_operations ixgbe_dbg_ts_bench_fops = {
	.owner = THIS_MODULE,
	.open = ixgbe_dbg_ts_bench_open,
	.release = ixgbe_dbg_ts_bench_release,
	.read = ixgbe_dbg_ts_bench_read,
	.write = ixgbe_dbg_ts_bench_write,
};

/**
 * ixgbe_dbg_adapter_init - setup the debugfs directory for the adapter
 * @adapter: the adapter that is starting up
 **/
void ixgbe_dbg_adapter_init(struct ixgbe_adapter *adapter)
{
	const char *name = pci_name(adapter->pdev);

	adapter->ixgbe_dbg_adapter = debugfs_create_dir(name, ixgbe_dbg_root);
	debugfs_create_file("reg_ops", 0600, adapter->ixgbe_dbg_adapter,
			    adapter, &ixgbe_dbg_reg_ops_fops);
	debugfs_create_file("netdev_ops", 0600, adapter->ixgbe_dbg_adapter,
			    adapter, &ixgbe_dbg_netdev_ops_fops);
	debugfs_create_file("sff_i2c", 0600, adapter->ixgbe_dbg_adapter,
			    adapter, &ixgbe_dbg_sff_i2c_fops);
	debugfs_create_file("ts_bench", 0600, adapter->ixgbe_dbg_adapter,
			    adapter, &ixgbe_dbg_ts_bench_fops);
}

/**
 * ixgbe_dbg_adapter_exit - clear out the adapter's debugfs entries
 * @adapter: the adapter that is exiting
 **/
void ixgbe_dbg_adapter_exit(struct ixgbe_adapter *adapter)
{
	debugfs_remove_recursive(adapter->ixgbe_dbg_adapter);
	adapter->ixgbe_dbg_adapter = NULL;
}

/**
 * ixgbe_dbg_init - start up debugfs for the driver
 **/
void ixgbe_dbg_init(void)
{
	ixgbe_dbg_root = debugfs_create_dir(ixgbe_driver_name, NULL);
}

/**
 * ixgbe_dbg_exit - clean out the driver's debugfs entries
 **/
void ixgbe_dbg_exit(void)
{
	debugfs_remove_recursive(ixgbe_dbg_root);
}