xref: /openbmc/linux/drivers/net/wireless/ath/ath6kl/debug.c (revision 91d57de5)

/*
 * Copyright (c) 2004-2011 Atheros Communications Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "core.h"

#include <linux/circ_buf.h>
#include <linux/fs.h>

#include "debug.h"
#include "target.h"

struct ath6kl_fwlog_slot {
	__le32 timestamp;
	__le32 length;

	/* max ATH6KL_FWLOG_PAYLOAD_SIZE bytes */
	u8 payload[0];
};

#define ATH6KL_FWLOG_SIZE 32768
#define ATH6KL_FWLOG_SLOT_SIZE (sizeof(struct ath6kl_fwlog_slot) + \
				ATH6KL_FWLOG_PAYLOAD_SIZE)
#define ATH6KL_FWLOG_VALID_MASK 0x1ffff

int ath6kl_printk(const char *level, const char *fmt, ...)
{
	struct va_format vaf;
	va_list args;
	int rtn;

	va_start(args, fmt);

	vaf.fmt = fmt;
	vaf.va = &args;

	rtn = printk("%sath6kl: %pV", level, &vaf);

	va_end(args);

	return rtn;
}

#ifdef CONFIG_ATH6KL_DEBUG

#define REG_OUTPUT_LEN_PER_LINE	25
#define REGTYPE_STR_LEN		100

struct ath6kl_diag_reg_info {
	u32 reg_start;
	u32 reg_end;
	const char *reg_info;
};

static const struct ath6kl_diag_reg_info diag_reg[] = {
	{ 0x20000, 0x200fc, "General DMA and Rx registers" },
	{ 0x28000, 0x28900, "MAC PCU register & keycache" },
	{ 0x20800, 0x20a40, "QCU" },
	{ 0x21000, 0x212f0, "DCU" },
	{ 0x4000,  0x42e4, "RTC" },
	{ 0x540000, 0x540000 + (256 * 1024), "RAM" },
	{ 0x29800, 0x2B210, "Base Band" },
	{ 0x1C000, 0x1C748, "Analog" },
};

void ath6kl_dump_registers(struct ath6kl_device *dev,
			   struct ath6kl_irq_proc_registers *irq_proc_reg,
			   struct ath6kl_irq_enable_reg *irq_enable_reg)
{

	ath6kl_dbg(ATH6KL_DBG_ANY, ("<------- Register Table -------->\n"));

	if (irq_proc_reg != NULL) {
		ath6kl_dbg(ATH6KL_DBG_ANY,
			"Host Int status:           0x%x\n",
			irq_proc_reg->host_int_status);
		ath6kl_dbg(ATH6KL_DBG_ANY,
			   "CPU Int status:            0x%x\n",
			irq_proc_reg->cpu_int_status);
		ath6kl_dbg(ATH6KL_DBG_ANY,
			   "Error Int status:          0x%x\n",
			irq_proc_reg->error_int_status);
		ath6kl_dbg(ATH6KL_DBG_ANY,
			   "Counter Int status:        0x%x\n",
			irq_proc_reg->counter_int_status);
		ath6kl_dbg(ATH6KL_DBG_ANY,
			   "Mbox Frame:                0x%x\n",
			irq_proc_reg->mbox_frame);
		ath6kl_dbg(ATH6KL_DBG_ANY,
			   "Rx Lookahead Valid:        0x%x\n",
			irq_proc_reg->rx_lkahd_valid);
		ath6kl_dbg(ATH6KL_DBG_ANY,
			   "Rx Lookahead 0:            0x%x\n",
			irq_proc_reg->rx_lkahd[0]);
		ath6kl_dbg(ATH6KL_DBG_ANY,
			   "Rx Lookahead 1:            0x%x\n",
			irq_proc_reg->rx_lkahd[1]);

		if (dev->ar->mbox_info.gmbox_addr != 0) {
			/*
			 * If the target supports GMBOX hardware, dump some
			 * additional state.
			 */
			ath6kl_dbg(ATH6KL_DBG_ANY,
				"GMBOX Host Int status 2:   0x%x\n",
				irq_proc_reg->host_int_status2);
			ath6kl_dbg(ATH6KL_DBG_ANY,
				"GMBOX RX Avail:            0x%x\n",
				irq_proc_reg->gmbox_rx_avail);
			ath6kl_dbg(ATH6KL_DBG_ANY,
				"GMBOX lookahead alias 0:   0x%x\n",
				irq_proc_reg->rx_gmbox_lkahd_alias[0]);
			ath6kl_dbg(ATH6KL_DBG_ANY,
				"GMBOX lookahead alias 1:   0x%x\n",
				irq_proc_reg->rx_gmbox_lkahd_alias[1]);
		}

	}

	if (irq_enable_reg != NULL) {
		ath6kl_dbg(ATH6KL_DBG_ANY,
			"Int status Enable:         0x%x\n",
			irq_enable_reg->int_status_en);
		ath6kl_dbg(ATH6KL_DBG_ANY, "Counter Int status Enable: 0x%x\n",
			irq_enable_reg->cntr_int_status_en);
	}
	ath6kl_dbg(ATH6KL_DBG_ANY, "<------------------------------->\n");
}

static void dump_cred_dist(struct htc_endpoint_credit_dist *ep_dist)
{
	ath6kl_dbg(ATH6KL_DBG_ANY,
		   "--- endpoint: %d  svc_id: 0x%X ---\n",
		   ep_dist->endpoint, ep_dist->svc_id);
	ath6kl_dbg(ATH6KL_DBG_ANY, " dist_flags     : 0x%X\n",
		   ep_dist->dist_flags);
	ath6kl_dbg(ATH6KL_DBG_ANY, " cred_norm      : %d\n",
		   ep_dist->cred_norm);
	ath6kl_dbg(ATH6KL_DBG_ANY, " cred_min       : %d\n",
		   ep_dist->cred_min);
	ath6kl_dbg(ATH6KL_DBG_ANY, " credits        : %d\n",
		   ep_dist->credits);
	ath6kl_dbg(ATH6KL_DBG_ANY, " cred_assngd    : %d\n",
		   ep_dist->cred_assngd);
	ath6kl_dbg(ATH6KL_DBG_ANY, " seek_cred      : %d\n",
		   ep_dist->seek_cred);
	ath6kl_dbg(ATH6KL_DBG_ANY, " cred_sz        : %d\n",
		   ep_dist->cred_sz);
	ath6kl_dbg(ATH6KL_DBG_ANY, " cred_per_msg   : %d\n",
		   ep_dist->cred_per_msg);
	ath6kl_dbg(ATH6KL_DBG_ANY, " cred_to_dist   : %d\n",
		   ep_dist->cred_to_dist);
	ath6kl_dbg(ATH6KL_DBG_ANY, " txq_depth      : %d\n",
		   get_queue_depth(&((struct htc_endpoint *)
				     ep_dist->htc_rsvd)->txq));
	ath6kl_dbg(ATH6KL_DBG_ANY,
		   "----------------------------------\n");
}

void dump_cred_dist_stats(struct htc_target *target)
{
	struct htc_endpoint_credit_dist *ep_list;

	if (!AR_DBG_LVL_CHECK(ATH6KL_DBG_TRC))
		return;

	list_for_each_entry(ep_list, &target->cred_dist_list, list)
		dump_cred_dist(ep_list);

	ath6kl_dbg(ATH6KL_DBG_HTC_SEND, "ctxt:%p dist:%p\n",
		   target->cred_dist_cntxt, NULL);
	ath6kl_dbg(ATH6KL_DBG_TRC, "credit distribution, total : %d, free : %d\n",
		   target->cred_dist_cntxt->total_avail_credits,
		   target->cred_dist_cntxt->cur_free_credits);
}

static int ath6kl_debugfs_open(struct inode *inode, struct file *file)
{
	file->private_data = inode->i_private;
	return 0;
}

static void ath6kl_debug_fwlog_add(struct ath6kl *ar, const void *buf,
				   size_t buf_len)
{
	struct circ_buf *fwlog = &ar->debug.fwlog_buf;
	size_t space;
	int i;

	/* entries must all be equal size */
	if (WARN_ON(buf_len != ATH6KL_FWLOG_SLOT_SIZE))
		return;

	space = CIRC_SPACE(fwlog->head, fwlog->tail, ATH6KL_FWLOG_SIZE);
	if (space < buf_len)
		/* discard oldest slot */
		fwlog->tail = (fwlog->tail + ATH6KL_FWLOG_SLOT_SIZE) &
			(ATH6KL_FWLOG_SIZE - 1);

	for (i = 0; i < buf_len; i += space) {
		space = CIRC_SPACE_TO_END(fwlog->head, fwlog->tail,
					  ATH6KL_FWLOG_SIZE);

		if ((size_t) space > buf_len - i)
			space = buf_len - i;

		memcpy(&fwlog->buf[fwlog->head], buf, space);
		fwlog->head = (fwlog->head + space) & (ATH6KL_FWLOG_SIZE - 1);
	}

}

void ath6kl_debug_fwlog_event(struct ath6kl *ar, const void *buf, size_t len)
{
	struct ath6kl_fwlog_slot *slot = ar->debug.fwlog_tmp;
	size_t slot_len;

	if (WARN_ON(len > ATH6KL_FWLOG_PAYLOAD_SIZE))
		return;

	spin_lock_bh(&ar->debug.fwlog_lock);

	slot->timestamp = cpu_to_le32(jiffies);
	slot->length = cpu_to_le32(len);
	memcpy(slot->payload, buf, len);

	slot_len = sizeof(*slot) + len;

	if (slot_len < ATH6KL_FWLOG_SLOT_SIZE)
		memset(slot->payload + len, 0,
		       ATH6KL_FWLOG_SLOT_SIZE - slot_len);

	ath6kl_debug_fwlog_add(ar, slot, ATH6KL_FWLOG_SLOT_SIZE);

	spin_unlock_bh(&ar->debug.fwlog_lock);
}

static bool ath6kl_debug_fwlog_empty(struct ath6kl *ar)
{
	return CIRC_CNT(ar->debug.fwlog_buf.head,
			ar->debug.fwlog_buf.tail,
			ATH6KL_FWLOG_SLOT_SIZE) == 0;
}

static ssize_t ath6kl_fwlog_read(struct file *file, char __user *user_buf,
				 size_t count, loff_t *ppos)
{
	struct ath6kl *ar = file->private_data;
	struct circ_buf *fwlog = &ar->debug.fwlog_buf;
	size_t len = 0, buf_len = count;
	ssize_t ret_cnt;
	char *buf;
	int ccnt;

	buf = vmalloc(buf_len);
	if (!buf)
		return -ENOMEM;

	/* read undelivered logs from firmware */
	ath6kl_read_fwlogs(ar);

	spin_lock_bh(&ar->debug.fwlog_lock);

	while (len < buf_len && !ath6kl_debug_fwlog_empty(ar)) {
		ccnt = CIRC_CNT_TO_END(fwlog->head, fwlog->tail,
				       ATH6KL_FWLOG_SIZE);

		if ((size_t) ccnt > buf_len - len)
			ccnt = buf_len - len;

		memcpy(buf + len, &fwlog->buf[fwlog->tail], ccnt);
		len += ccnt;

		fwlog->tail = (fwlog->tail + ccnt) &
			(ATH6KL_FWLOG_SIZE - 1);
	}

	spin_unlock_bh(&ar->debug.fwlog_lock);

	if (WARN_ON(len > buf_len))
		len = buf_len;

	ret_cnt = simple_read_from_buffer(user_buf, count, ppos, buf, len);

	vfree(buf);

	return ret_cnt;
}

static const struct file_operations fops_fwlog = {
	.open = ath6kl_debugfs_open,
	.read = ath6kl_fwlog_read,
	.owner = THIS_MODULE,
	.llseek = default_llseek,
};

static ssize_t ath6kl_fwlog_mask_read(struct file *file, char __user *user_buf,
				      size_t count, loff_t *ppos)
{
	struct ath6kl *ar = file->private_data;
	char buf[16];
	int len;

	len = snprintf(buf, sizeof(buf), "0x%x\n", ar->debug.fwlog_mask);

	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
}

static ssize_t ath6kl_fwlog_mask_write(struct file *file,
				       const char __user *user_buf,
				       size_t count, loff_t *ppos)
{
	struct ath6kl *ar = file->private_data;
	int ret;

	ret = kstrtou32_from_user(user_buf, count, 0, &ar->debug.fwlog_mask);
	if (ret)
		return ret;

	ret = ath6kl_wmi_config_debug_module_cmd(ar->wmi,
						 ATH6KL_FWLOG_VALID_MASK,
						 ar->debug.fwlog_mask);
	if (ret)
		return ret;

	return count;
}

static const struct file_operations fops_fwlog_mask = {
	.open = ath6kl_debugfs_open,
	.read = ath6kl_fwlog_mask_read,
	.write = ath6kl_fwlog_mask_write,
	.owner = THIS_MODULE,
	.llseek = default_llseek,
};

static ssize_t read_file_tgt_stats(struct file *file, char __user *user_buf,
				   size_t count, loff_t *ppos)
{
	struct ath6kl *ar = file->private_data;
	struct target_stats *tgt_stats = &ar->target_stats;
	char *buf;
	unsigned int len = 0, buf_len = 1500;
	int i;
	long left;
	ssize_t ret_cnt;

	buf = kzalloc(buf_len, GFP_KERNEL);
	if (!buf)
		return -ENOMEM;

	if (down_interruptible(&ar->sem)) {
		kfree(buf);
		return -EBUSY;
	}

	set_bit(STATS_UPDATE_PEND, &ar->flag);

	if (ath6kl_wmi_get_stats_cmd(ar->wmi)) {
		up(&ar->sem);
		kfree(buf);
		return -EIO;
	}

	left = wait_event_interruptible_timeout(ar->event_wq,
						!test_bit(STATS_UPDATE_PEND,
						&ar->flag), WMI_TIMEOUT);

	up(&ar->sem);

	if (left <= 0) {
		kfree(buf);
		return -ETIMEDOUT;
	}

	len += scnprintf(buf + len, buf_len - len, "\n");
	len += scnprintf(buf + len, buf_len - len, "%25s\n",
			 "Target Tx stats");
	len += scnprintf(buf + len, buf_len - len, "%25s\n\n",
			 "=================");
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Ucast packets", tgt_stats->tx_ucast_pkt);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Bcast packets", tgt_stats->tx_bcast_pkt);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Ucast byte", tgt_stats->tx_ucast_byte);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Bcast byte", tgt_stats->tx_bcast_byte);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Rts success cnt", tgt_stats->tx_rts_success_cnt);
	for (i = 0; i < 4; i++)
		len += scnprintf(buf + len, buf_len - len,
				 "%18s %d %10llu\n", "PER on ac",
				 i, tgt_stats->tx_pkt_per_ac[i]);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Error", tgt_stats->tx_err);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Fail count", tgt_stats->tx_fail_cnt);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Retry count", tgt_stats->tx_retry_cnt);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Multi retry cnt", tgt_stats->tx_mult_retry_cnt);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Rts fail cnt", tgt_stats->tx_rts_fail_cnt);
	len += scnprintf(buf + len, buf_len - len, "%25s %10llu\n\n",
			 "TKIP counter measure used",
			 tgt_stats->tkip_cnter_measures_invoked);

	len += scnprintf(buf + len, buf_len - len, "%25s\n",
			 "Target Rx stats");
	len += scnprintf(buf + len, buf_len - len, "%25s\n",
			 "=================");

	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Ucast packets", tgt_stats->rx_ucast_pkt);
	len += scnprintf(buf + len, buf_len - len, "%20s %10d\n",
			 "Ucast Rate", tgt_stats->rx_ucast_rate);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Bcast packets", tgt_stats->rx_bcast_pkt);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Ucast byte", tgt_stats->rx_ucast_byte);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Bcast byte", tgt_stats->rx_bcast_byte);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Fragmented pkt", tgt_stats->rx_frgment_pkt);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Error", tgt_stats->rx_err);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "CRC Err", tgt_stats->rx_crc_err);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Key chache miss", tgt_stats->rx_key_cache_miss);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Decrypt Err", tgt_stats->rx_decrypt_err);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Duplicate frame", tgt_stats->rx_dupl_frame);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Tkip Mic failure", tgt_stats->tkip_local_mic_fail);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "TKIP format err", tgt_stats->tkip_fmt_err);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "CCMP format Err", tgt_stats->ccmp_fmt_err);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n\n",
			 "CCMP Replay Err", tgt_stats->ccmp_replays);

	len += scnprintf(buf + len, buf_len - len, "%25s\n",
			 "Misc Target stats");
	len += scnprintf(buf + len, buf_len - len, "%25s\n",
			 "=================");
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Beacon Miss count", tgt_stats->cs_bmiss_cnt);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Num Connects", tgt_stats->cs_connect_cnt);
	len += scnprintf(buf + len, buf_len - len, "%20s %10llu\n",
			 "Num disconnects", tgt_stats->cs_discon_cnt);
	len += scnprintf(buf + len, buf_len - len, "%20s %10d\n",
			 "Beacon avg rssi", tgt_stats->cs_ave_beacon_rssi);

	if (len > buf_len)
		len = buf_len;

	ret_cnt = simple_read_from_buffer(user_buf, count, ppos, buf, len);

	kfree(buf);
	return ret_cnt;
}

static const struct file_operations fops_tgt_stats = {
	.read = read_file_tgt_stats,
	.open = ath6kl_debugfs_open,
	.owner = THIS_MODULE,
	.llseek = default_llseek,
};

#define print_credit_info(fmt_str, ep_list_field)		\
	(len += scnprintf(buf + len, buf_len - len, fmt_str,	\
			 ep_list->ep_list_field))
#define CREDIT_INFO_DISPLAY_STRING_LEN	200
#define CREDIT_INFO_LEN	128

static ssize_t read_file_credit_dist_stats(struct file *file,
					   char __user *user_buf,
					   size_t count, loff_t *ppos)
{
	struct ath6kl *ar = file->private_data;
	struct htc_target *target = ar->htc_target;
	struct htc_endpoint_credit_dist *ep_list;
	char *buf;
	unsigned int buf_len, len = 0;
	ssize_t ret_cnt;

	buf_len = CREDIT_INFO_DISPLAY_STRING_LEN +
		  get_queue_depth(&target->cred_dist_list) * CREDIT_INFO_LEN;
	buf = kzalloc(buf_len, GFP_KERNEL);
	if (!buf)
		return -ENOMEM;

	len += scnprintf(buf + len, buf_len - len, "%25s%5d\n",
			 "Total Avail Credits: ",
			 target->cred_dist_cntxt->total_avail_credits);
	len += scnprintf(buf + len, buf_len - len, "%25s%5d\n",
			 "Free credits :",
			 target->cred_dist_cntxt->cur_free_credits);

	len += scnprintf(buf + len, buf_len - len,
			 " Epid  Flags    Cred_norm  Cred_min  Credits  Cred_assngd"
			 "  Seek_cred  Cred_sz  Cred_per_msg  Cred_to_dist"
			 "  qdepth\n");

	list_for_each_entry(ep_list, &target->cred_dist_list, list) {
		print_credit_info("  %2d", endpoint);
		print_credit_info("%10x", dist_flags);
		print_credit_info("%8d", cred_norm);
		print_credit_info("%9d", cred_min);
		print_credit_info("%9d", credits);
		print_credit_info("%10d", cred_assngd);
		print_credit_info("%13d", seek_cred);
		print_credit_info("%12d", cred_sz);
		print_credit_info("%9d", cred_per_msg);
		print_credit_info("%14d", cred_to_dist);
		len += scnprintf(buf + len, buf_len - len, "%12d\n",
				 get_queue_depth(&((struct htc_endpoint *)
						 ep_list->htc_rsvd)->txq));
	}

	if (len > buf_len)
		len = buf_len;

	ret_cnt = simple_read_from_buffer(user_buf, count, ppos, buf, len);
	kfree(buf);
	return ret_cnt;
}

static const struct file_operations fops_credit_dist_stats = {
	.read = read_file_credit_dist_stats,
	.open = ath6kl_debugfs_open,
	.owner = THIS_MODULE,
	.llseek = default_llseek,
};

static unsigned long ath6kl_get_num_reg(void)
{
	int i;
	unsigned long n_reg = 0;

	for (i = 0; i < ARRAY_SIZE(diag_reg); i++)
		n_reg = n_reg +
		     (diag_reg[i].reg_end - diag_reg[i].reg_start) / 4 + 1;

	return n_reg;
}

static bool ath6kl_dbg_is_diag_reg_valid(u32 reg_addr)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(diag_reg); i++) {
		if (reg_addr >= diag_reg[i].reg_start &&
		    reg_addr <= diag_reg[i].reg_end)
			return true;
	}

	return false;
}

static ssize_t ath6kl_regread_read(struct file *file, char __user *user_buf,
				    size_t count, loff_t *ppos)
{
	struct ath6kl *ar = file->private_data;
	u8 buf[50];
	unsigned int len = 0;

	if (ar->debug.dbgfs_diag_reg)
		len += scnprintf(buf + len, sizeof(buf) - len, "0x%x\n",
				ar->debug.dbgfs_diag_reg);
	else
		len += scnprintf(buf + len, sizeof(buf) - len,
				 "All diag registers\n");

	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
}

static ssize_t ath6kl_regread_write(struct file *file,
				    const char __user *user_buf,
				    size_t count, loff_t *ppos)
{
	struct ath6kl *ar = file->private_data;
	u8 buf[50];
	unsigned int len;
	unsigned long reg_addr;

	len = min(count, sizeof(buf) - 1);
	if (copy_from_user(buf, user_buf, len))
		return -EFAULT;

	buf[len] = '\0';

	if (strict_strtoul(buf, 0, &reg_addr))
		return -EINVAL;

	if ((reg_addr % 4) != 0)
		return -EINVAL;

	if (reg_addr && !ath6kl_dbg_is_diag_reg_valid(reg_addr))
		return -EINVAL;

	ar->debug.dbgfs_diag_reg = reg_addr;

	return count;
}

static const struct file_operations fops_diag_reg_read = {
	.read = ath6kl_regread_read,
	.write = ath6kl_regread_write,
	.open = ath6kl_debugfs_open,
	.owner = THIS_MODULE,
	.llseek = default_llseek,
};

static int ath6kl_regdump_open(struct inode *inode, struct file *file)
{
	struct ath6kl *ar = inode->i_private;
	u8 *buf;
	unsigned long int reg_len;
	unsigned int len = 0, n_reg;
	u32 addr;
	__le32 reg_val;
	int i, status;

	/* Dump all the registers if no register is specified */
	if (!ar->debug.dbgfs_diag_reg)
		n_reg = ath6kl_get_num_reg();
	else
		n_reg = 1;

	reg_len = n_reg * REG_OUTPUT_LEN_PER_LINE;
	if (n_reg > 1)
		reg_len += REGTYPE_STR_LEN;

	buf = vmalloc(reg_len);
	if (!buf)
		return -ENOMEM;

	if (n_reg == 1) {
		addr = ar->debug.dbgfs_diag_reg;

		status = ath6kl_diag_read32(ar,
				TARG_VTOP(ar->target_type, addr),
				(u32 *)&reg_val);
		if (status)
			goto fail_reg_read;

		len += scnprintf(buf + len, reg_len - len,
				 "0x%06x 0x%08x\n", addr, le32_to_cpu(reg_val));
		goto done;
	}

	for (i = 0; i < ARRAY_SIZE(diag_reg); i++) {
		len += scnprintf(buf + len, reg_len - len,
				"%s\n", diag_reg[i].reg_info);
		for (addr = diag_reg[i].reg_start;
		     addr <= diag_reg[i].reg_end; addr += 4) {
			status = ath6kl_diag_read32(ar,
					TARG_VTOP(ar->target_type, addr),
					(u32 *)&reg_val);
			if (status)
				goto fail_reg_read;

			len += scnprintf(buf + len, reg_len - len,
					"0x%06x 0x%08x\n",
					addr, le32_to_cpu(reg_val));
		}
	}

done:
	file->private_data = buf;
	return 0;

fail_reg_read:
	ath6kl_warn("Unable to read memory:%u\n", addr);
	vfree(buf);
	return -EIO;
}

static ssize_t ath6kl_regdump_read(struct file *file, char __user *user_buf,
				  size_t count, loff_t *ppos)
{
	u8 *buf = file->private_data;
	return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf));
}

static int ath6kl_regdump_release(struct inode *inode, struct file *file)
{
	vfree(file->private_data);
	return 0;
}

static const struct file_operations fops_reg_dump = {
	.open = ath6kl_regdump_open,
	.read = ath6kl_regdump_read,
	.release = ath6kl_regdump_release,
	.owner = THIS_MODULE,
	.llseek = default_llseek,
};

int ath6kl_debug_init(struct ath6kl *ar)
{
	ar->debug.fwlog_buf.buf = vmalloc(ATH6KL_FWLOG_SIZE);
	if (ar->debug.fwlog_buf.buf == NULL)
		return -ENOMEM;

	ar->debug.fwlog_tmp = kmalloc(ATH6KL_FWLOG_SLOT_SIZE, GFP_KERNEL);
	if (ar->debug.fwlog_tmp == NULL) {
		vfree(ar->debug.fwlog_buf.buf);
		return -ENOMEM;
	}

	spin_lock_init(&ar->debug.fwlog_lock);

	/*
	 * Actually we are lying here but don't know how to read the mask
	 * value from the firmware.
	 */
	ar->debug.fwlog_mask = 0;

	ar->debugfs_phy = debugfs_create_dir("ath6kl",
					     ar->wdev->wiphy->debugfsdir);
	if (!ar->debugfs_phy) {
		vfree(ar->debug.fwlog_buf.buf);
		kfree(ar->debug.fwlog_tmp);
		return -ENOMEM;
	}

	debugfs_create_file("tgt_stats", S_IRUSR, ar->debugfs_phy, ar,
			    &fops_tgt_stats);

	debugfs_create_file("credit_dist_stats", S_IRUSR, ar->debugfs_phy, ar,
			    &fops_credit_dist_stats);

	debugfs_create_file("fwlog", S_IRUSR, ar->debugfs_phy, ar,
			    &fops_fwlog);

	debugfs_create_file("fwlog_mask", S_IRUSR | S_IWUSR, ar->debugfs_phy,
			    ar, &fops_fwlog_mask);

	debugfs_create_file("reg_addr", S_IRUSR | S_IWUSR, ar->debugfs_phy, ar,
			    &fops_diag_reg_read);

	debugfs_create_file("reg_dump", S_IRUSR, ar->debugfs_phy, ar,
			    &fops_reg_dump);

	return 0;
}

void ath6kl_debug_cleanup(struct ath6kl *ar)
{
	vfree(ar->debug.fwlog_buf.buf);
	kfree(ar->debug.fwlog_tmp);
}

#endif