ath10k: add debugfs file warm_hw_reset

Debugfs support to do hardware warm reset with WMI command
WMI_PDEV_PARAM_PDEV_RESET for 10.4 and 10.2.4(if wmi
service is enabled in the firmware for backward compatibility).

This change is purely for debugging purpose when hardware hangs/mutes.

This hardware reset won't affect the connectivity but there will be small
pause in data traffic. Here we are doing BB/MAC level reset and hence
whenever the BB/MAC watchdog is triggered, it does a hardware_chip_reset.
So the target will be in the active state.

Below command used to warm reset the hardware.
echo 1 > /sys/kernel/debug/ieee80211/phyX/ath10k/warm_hw_reset

Tested in QCA988X with firmware ver 10.2.4.70.45
Tested in QCA4019 with firmware ver 10.4-3.2.1.1-00011

Signed-off-by: Maharaja Kennadyrajan <mkenna@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

1 files changed, 49 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/ath10k/debug.c b/drivers/net/wireless/ath/ath10k/debug.c
index 4926722e0c0d..0baaad90b8d1 100644
--- a/drivers/net/wireless/ath/ath10k/debug.c
+++ b/drivers/net/wireless/ath/ath10k/debug.c
@@ -2297,6 +2297,52 @@ static const struct file_operations fops_tpc_stats_final = {
 	.llseek = default_llseek,
 };
 
+static ssize_t ath10k_write_warm_hw_reset(struct file *file,
+					  const char __user *user_buf,
+					  size_t count, loff_t *ppos)
+{
+	struct ath10k *ar = file->private_data;
+	int ret;
+	bool val;
+
+	if (kstrtobool_from_user(user_buf, count, &val))
+		return -EFAULT;
+
+	if (!val)
+		return -EINVAL;
+
+	mutex_lock(&ar->conf_mutex);
+
+	if (ar->state != ATH10K_STATE_ON) {
+		ret = -ENETDOWN;
+		goto exit;
+	}
+
+	if (!(test_bit(WMI_SERVICE_RESET_CHIP, ar->wmi.svc_map)))
+		ath10k_warn(ar, "wmi service for reset chip is not available\n");
+
+	ret = ath10k_wmi_pdev_set_param(ar, ar->wmi.pdev_param->pdev_reset,
+					WMI_RST_MODE_WARM_RESET);
+
+	if (ret) {
+		ath10k_warn(ar, "failed to enable warm hw reset: %d\n", ret);
+		goto exit;
+	}
+
+	ret = count;
+
+exit:
+	mutex_unlock(&ar->conf_mutex);
+	return ret;
+}
+
+static const struct file_operations fops_warm_hw_reset = {
+	.write = ath10k_write_warm_hw_reset,
+	.open = simple_open,
+	.owner = THIS_MODULE,
+	.llseek = default_llseek,
+};
+
 int ath10k_debug_create(struct ath10k *ar)
 {
 	ar->debug.cal_data = vzalloc(ATH10K_DEBUG_CAL_DATA_LEN);
@@ -2425,6 +2471,9 @@ int ath10k_debug_register(struct ath10k *ar)
 				    ar->debug.debugfs_phy, ar,
 				    &fops_tpc_stats_final);
 
+	debugfs_create_file("warm_hw_reset", 0600, ar->debug.debugfs_phy, ar,
+			    &fops_warm_hw_reset);
+
 	return 0;
 }