Bluetooth: btnxpuart: Add support for HCI coredump feature

This adds support for Bluetooth Coredump feature to BTNXPUART driver to
collect FW dumps on demand, or in case FW goes in a bad state.

To trigger manual FW dump, following command can be used:
echo 1 > /sys/class/bluetooth/hci0/device/coredump

Once FW dump is complete, it can be written to a file:
cat /sys/class/bluetooth/hci0/devcoredump/data > fw_dump

While FW dump is in progress, any HCI command will return -EBUSY.

After FW dump is complete, driver will give HCI_NXP_IND_RESET command
which soft-resets the chip, allowing FW re-download.

Signed-off-by: Neeraj Sanjay Kale <neeraj.sanjaykale@nxp.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

diff --git a/drivers/bluetooth/btnxpuart.c b/drivers/bluetooth/btnxpuart.c
index 5f07a57532cb6e1e5dea4a2a75ec35f2c540382f..97c3d3ae2f72f724905ba82ae457b9dfb696adb3 100644 (file)
--- a/drivers/bluetooth/btnxpuart.c
+++ b/drivers/bluetooth/btnxpuart.c
@@ -31,6 +31,7 @@
 #define BTNXPUART_SERDEV_OPEN          4
 #define BTNXPUART_IR_IN_PROGRESS       5
 #define BTNXPUART_FW_DOWNLOAD_ABORT    6
+#define BTNXPUART_FW_DUMP_IN_PROGRESS  7
 
 /* NXP HW err codes */
 #define BTNXPUART_IR_HW_ERR            0xb0
@@ -106,6 +107,8 @@
 #define HCI_NXP_SET_OPER_SPEED 0xfc09
 /* Bluetooth vendor command: Independent Reset */
 #define HCI_NXP_IND_RESET      0xfcfc
+/* Bluetooth vendor command: Trigger FW dump */
+#define HCI_NXP_TRIGGER_DUMP   0xfe91
 
 /* Bluetooth Power State : Vendor cmd params */
 #define BT_PS_ENABLE                   0x02
@@ -310,6 +313,16 @@ union nxp_v3_rx_timeout_nak_u {
        u8 buf[6];
 };
 
+/* FW dump */
+#define NXP_FW_DUMP_SIZE       (1024 * 1000)
+
+struct nxp_fw_dump_hdr {
+       __le16 seq_num;
+       __le16 reserved;
+       __le16 buf_type;
+       __le16 buf_len;
+};
+
 static u8 crc8_table[CRC8_TABLE_SIZE];
 
 /* Default configurations */
@@ -774,6 +787,16 @@ static bool is_fw_downloading(struct btnxpuart_dev *nxpdev)
        return test_bit(BTNXPUART_FW_DOWNLOADING, &nxpdev->tx_state);
 }
 
+static bool ind_reset_in_progress(struct btnxpuart_dev *nxpdev)
+{
+       return test_bit(BTNXPUART_IR_IN_PROGRESS, &nxpdev->tx_state);
+}
+
+static bool fw_dump_in_progress(struct btnxpuart_dev *nxpdev)
+{
+       return test_bit(BTNXPUART_FW_DUMP_IN_PROGRESS, &nxpdev->tx_state);
+}
+
 static bool process_boot_signature(struct btnxpuart_dev *nxpdev)
 {
        if (test_bit(BTNXPUART_CHECK_BOOT_SIGNATURE, &nxpdev->tx_state)) {
@@ -1175,7 +1198,7 @@ static int nxp_set_baudrate_cmd(struct hci_dev *hdev, void *data)
 static int nxp_check_boot_sign(struct btnxpuart_dev *nxpdev)
 {
        serdev_device_set_baudrate(nxpdev->serdev, HCI_NXP_PRI_BAUDRATE);
-       if (test_bit(BTNXPUART_IR_IN_PROGRESS, &nxpdev->tx_state))
+       if (ind_reset_in_progress(nxpdev))
                serdev_device_set_flow_control(nxpdev->serdev, false);
        else
                serdev_device_set_flow_control(nxpdev->serdev, true);
@@ -1204,6 +1227,73 @@ static int nxp_set_ind_reset(struct hci_dev *hdev, void *data)
        return hci_recv_frame(hdev, skb);
 }
 
+/* Firmware dump */
+static void nxp_coredump(struct hci_dev *hdev)
+{
+       struct sk_buff *skb;
+       u8 pcmd = 2;
+
+       skb = nxp_drv_send_cmd(hdev, HCI_NXP_TRIGGER_DUMP, 1, &pcmd);
+       if (!IS_ERR(skb))
+               kfree_skb(skb);
+}
+
+static void nxp_coredump_hdr(struct hci_dev *hdev, struct sk_buff *skb)
+{
+       /* Nothing to be added in FW dump header */
+}
+
+static int nxp_process_fw_dump(struct hci_dev *hdev, struct sk_buff *skb)
+{
+       struct hci_acl_hdr *acl_hdr = (struct hci_acl_hdr *)skb_pull_data(skb,
+                                                                         sizeof(*acl_hdr));
+       struct nxp_fw_dump_hdr *fw_dump_hdr = (struct nxp_fw_dump_hdr *)skb->data;
+       struct btnxpuart_dev *nxpdev = hci_get_drvdata(hdev);
+       __u16 seq_num = __le16_to_cpu(fw_dump_hdr->seq_num);
+       __u16 buf_len = __le16_to_cpu(fw_dump_hdr->buf_len);
+       int err;
+
+       if (seq_num == 0x0001) {
+               if (test_and_set_bit(BTNXPUART_FW_DUMP_IN_PROGRESS, &nxpdev->tx_state)) {
+                       bt_dev_err(hdev, "FW dump already in progress");
+                       goto free_skb;
+               }
+               bt_dev_warn(hdev, "==== Start FW dump ===");
+               err = hci_devcd_init(hdev, NXP_FW_DUMP_SIZE);
+               if (err < 0)
+                       goto free_skb;
+
+               schedule_delayed_work(&hdev->dump.dump_timeout,
+                                     msecs_to_jiffies(20000));
+       }
+
+       err = hci_devcd_append(hdev, skb_clone(skb, GFP_ATOMIC));
+       if (err < 0)
+               goto free_skb;
+
+       if (buf_len == 0) {
+               bt_dev_warn(hdev, "==== FW dump complete ===");
+               clear_bit(BTNXPUART_FW_DUMP_IN_PROGRESS, &nxpdev->tx_state);
+               hci_devcd_complete(hdev);
+               nxp_set_ind_reset(hdev, NULL);
+       }
+
+free_skb:
+       kfree_skb(skb);
+       return 0;
+}
+
+static int nxp_recv_acl_pkt(struct hci_dev *hdev, struct sk_buff *skb)
+{
+       __u16 handle = __le16_to_cpu(hci_acl_hdr(skb)->handle);
+
+       /* FW dump chunks are ACL packets with conn handle 0xfff */
+       if ((handle & 0x0FFF) == 0xFFF)
+               return nxp_process_fw_dump(hdev, skb);
+       else
+               return hci_recv_frame(hdev, skb);
+}
+
 /* NXP protocol */
 static int nxp_setup(struct hci_dev *hdev)
 {
@@ -1265,20 +1355,15 @@ static int nxp_shutdown(struct hci_dev *hdev)
 {
        struct btnxpuart_dev *nxpdev = hci_get_drvdata(hdev);
        struct sk_buff *skb;
-       u8 *status;
        u8 pcmd = 0;
 
-       if (test_bit(BTNXPUART_IR_IN_PROGRESS, &nxpdev->tx_state)) {
+       if (ind_reset_in_progress(nxpdev)) {
                skb = nxp_drv_send_cmd(hdev, HCI_NXP_IND_RESET, 1, &pcmd);
-               if (IS_ERR(skb))
-                       return PTR_ERR(skb);
-
-               status = skb_pull_data(skb, 1);
-               if (status) {
-                       serdev_device_set_flow_control(nxpdev->serdev, false);
-                       set_bit(BTNXPUART_FW_DOWNLOADING, &nxpdev->tx_state);
-               }
-               kfree_skb(skb);
+               serdev_device_set_flow_control(nxpdev->serdev, false);
+               set_bit(BTNXPUART_FW_DOWNLOADING, &nxpdev->tx_state);
+               /* HCI_NXP_IND_RESET command may not returns any response */
+               if (!IS_ERR(skb))
+                       kfree_skb(skb);
        } else if (nxpdev->current_baudrate != nxpdev->fw_init_baudrate) {
                nxpdev->new_baudrate = nxpdev->fw_init_baudrate;
                nxp_set_baudrate_cmd(hdev, NULL);
@@ -1298,6 +1383,16 @@ static bool nxp_wakeup(struct hci_dev *hdev)
        return false;
 }
 
+static void nxp_reset(struct hci_dev *hdev)
+{
+       struct btnxpuart_dev *nxpdev = hci_get_drvdata(hdev);
+
+       if (!ind_reset_in_progress(nxpdev) && !fw_dump_in_progress(nxpdev)) {
+               bt_dev_dbg(hdev, "CMD Timeout detected. Resetting.");
+               nxp_set_ind_reset(hdev, NULL);
+       }
+}
+
 static int btnxpuart_queue_skb(struct hci_dev *hdev, struct sk_buff *skb)
 {
        struct btnxpuart_dev *nxpdev = hci_get_drvdata(hdev);
@@ -1318,6 +1413,9 @@ static int nxp_enqueue(struct hci_dev *hdev, struct sk_buff *skb)
        struct wakeup_cmd_payload wakeup_parm;
        __le32 baudrate_parm;
 
+       if (fw_dump_in_progress(nxpdev))
+               return -EBUSY;
+
        /* if vendor commands are received from user space (e.g. hcitool), update
         * driver flags accordingly and ask driver to re-send the command to FW.
         * In case the payload for any command does not match expected payload
@@ -1486,7 +1584,7 @@ static int btnxpuart_flush(struct hci_dev *hdev)
 }
 
 static const struct h4_recv_pkt nxp_recv_pkts[] = {
-       { H4_RECV_ACL,          .recv = hci_recv_frame },
+       { H4_RECV_ACL,          .recv = nxp_recv_acl_pkt },
        { H4_RECV_SCO,          .recv = hci_recv_frame },
        { H4_RECV_EVENT,        .recv = hci_recv_frame },
        { H4_RECV_ISO,          .recv = hci_recv_frame },
@@ -1508,11 +1606,13 @@ static size_t btnxpuart_receive_buf(struct serdev_device *serdev,
        if (IS_ERR(nxpdev->rx_skb)) {
                int err = PTR_ERR(nxpdev->rx_skb);
                /* Safe to ignore out-of-sync bootloader signatures */
-               if (!is_fw_downloading(nxpdev))
+               if (!is_fw_downloading(nxpdev) &&
+                   !ind_reset_in_progress(nxpdev))
                        bt_dev_err(nxpdev->hdev, "Frame reassembly failed (%d)", err);
                return count;
        }
-       if (!is_fw_downloading(nxpdev))
+       if (!is_fw_downloading(nxpdev) &&
+           !ind_reset_in_progress(nxpdev))
                nxpdev->hdev->stat.byte_rx += count;
        return count;
 }
@@ -1580,6 +1680,7 @@ static int nxp_serdev_probe(struct serdev_device *serdev)
        hdev->hw_error = nxp_hw_err;
        hdev->shutdown = nxp_shutdown;
        hdev->wakeup = nxp_wakeup;
+       hdev->reset = nxp_reset;
        SET_HCIDEV_DEV(hdev, &serdev->dev);
 
        if (hci_register_dev(hdev) < 0) {
@@ -1590,6 +1691,8 @@ static int nxp_serdev_probe(struct serdev_device *serdev)
        if (ps_setup(hdev))
                goto probe_fail;
 
+       hci_devcd_register(hdev, nxp_coredump, nxp_coredump_hdr, NULL);
+
        return 0;
 
 probe_fail:
@@ -1641,6 +1744,17 @@ static int nxp_serdev_resume(struct device *dev)
 }
 #endif
 
+#ifdef CONFIG_DEV_COREDUMP
+static void nxp_serdev_coredump(struct device *dev)
+{
+       struct btnxpuart_dev *nxpdev = dev_get_drvdata(dev);
+       struct hci_dev  *hdev = nxpdev->hdev;
+
+       if (hdev->dump.coredump)
+               hdev->dump.coredump(hdev);
+}
+#endif
+
 static struct btnxpuart_data w8987_data __maybe_unused = {
        .helper_fw_name = NULL,
        .fw_name = FIRMWARE_W8987,
@@ -1671,6 +1785,9 @@ static struct serdev_device_driver nxp_serdev_driver = {
                .name = "btnxpuart",
                .of_match_table = of_match_ptr(nxpuart_of_match_table),
                .pm = &nxp_pm_ops,
+#ifdef CONFIG_DEV_COREDUMP
+               .coredump = nxp_serdev_coredump,
+#endif
        },
 };