[v5,3/3] Bluetooth: btusb: mediatek: add MediaTek devcoredump support

From: Jing Cai <jing.cai@mediatek.com>

This patch implement function .coredump() and dmp_hdr() in btusb
driver for MediaTek controller.  FW core dump was triggered by FW
specific event to show something unexpected happened in the controller.

The driver would be responsible for collecting and uploading the device
core dump pieces in hci driver using core dump API. Once we finished
the whole process, the driver would reset the controller to recover the
kind of fatal error.

Co-developed-by: Chris Lu <chris.lu@mediatek.com>
Signed-off-by: Chris Lu <chris.lu@mediatek.com>
Co-developed-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Jing Cai <jing.cai@mediatek.com>
---
v2, v3: rebase onto the latest codebase
v4: update the newest API usage for the coredump which was already
    into the upstream
v5: support devcoredump on hdev basis
---
 drivers/bluetooth/btmtk.c | 117 ++++++++++++++++++++++++++++++++++++++
 drivers/bluetooth/btmtk.h |  28 +++++++++
 drivers/bluetooth/btusb.c |  14 +++++
 3 files changed, 159 insertions(+)

Hi Sean,

On Tue, May 2, 2023 at 4:02 PM <sean.wang@mediatek.com> wrote:
>
> From: Jing Cai <jing.cai@mediatek.com>
>
> This patch implement function .coredump() and dmp_hdr() in btusb
> driver for MediaTek controller.  FW core dump was triggered by FW
> specific event to show something unexpected happened in the controller.
>
> The driver would be responsible for collecting and uploading the device
> core dump pieces in hci driver using core dump API. Once we finished
> the whole process, the driver would reset the controller to recover the
> kind of fatal error.
>
> Co-developed-by: Chris Lu <chris.lu@mediatek.com>
> Signed-off-by: Chris Lu <chris.lu@mediatek.com>
> Co-developed-by: Sean Wang <sean.wang@mediatek.com>
> Signed-off-by: Sean Wang <sean.wang@mediatek.com>
> Signed-off-by: Jing Cai <jing.cai@mediatek.com>
> ---
> v2, v3: rebase onto the latest codebase
> v4: update the newest API usage for the coredump which was already
>     into the upstream
> v5: support devcoredump on hdev basis
> ---
>  drivers/bluetooth/btmtk.c | 117 ++++++++++++++++++++++++++++++++++++++
>  drivers/bluetooth/btmtk.h |  28 +++++++++
>  drivers/bluetooth/btusb.c |  14 +++++
>  3 files changed, 159 insertions(+)
>
> diff --git a/drivers/bluetooth/btmtk.c b/drivers/bluetooth/btmtk.c
> index ac2fac7e3c5f..657792f9dcab 100644
> --- a/drivers/bluetooth/btmtk.c
> +++ b/drivers/bluetooth/btmtk.c
> @@ -19,6 +19,12 @@
>  #define MTK_SEC_MAP_COMMON_SIZE        12
>  #define MTK_SEC_MAP_NEED_SEND_SIZE     52
>
> +enum {
> +       BTMTK_COREDUMP_INIT,
> +       BTMTK_COREDUMP_DISABLED,
> +       BTMTK_COREDUMP_ACTIVE,
> +};
> +
>  struct btmtk_patch_header {
>         u8 datetime[16];
>         u8 platform[4];
> @@ -53,6 +59,56 @@ struct btmtk_section_map {
>         };
>  } __packed;
>
> +static void btmtk_coredump(struct hci_dev *hdev)
> +{
> +       int err;
> +
> +       err = __hci_cmd_send(hdev, 0xfd5b, 0, NULL);
> +       if (err < 0)
> +               bt_dev_err(hdev, "Coredump failed (%d)", err);
> +}
> +
> +static void btmtk_coredump_hdr(struct hci_dev *hdev, struct sk_buff *skb)
> +{
> +       struct btmtk_data *data = hci_get_priv(hdev);
> +       char buf[80];
> +
> +       snprintf(buf, sizeof(buf), "Controller Name: 0x%X\n",
> +                data->cd_info.dev_id);
> +       skb_put_data(skb, buf, strlen(buf));
> +
> +       snprintf(buf, sizeof(buf), "Firmware Version: 0x%X\n",
> +                data->cd_info.fw_version);
> +       skb_put_data(skb, buf, strlen(buf));
> +
> +       snprintf(buf, sizeof(buf), "Driver: %s\n",
> +                data->cd_info.driver_name);
> +       skb_put_data(skb, buf, strlen(buf));
> +
> +       snprintf(buf, sizeof(buf), "Vendor: MediaTek\n");
> +       skb_put_data(skb, buf, strlen(buf));
> +}
> +
> +static void btmtk_coredump_notify(struct hci_dev *hdev, int state)
> +{
> +       struct btmtk_data *data = hci_get_priv(hdev);
> +
> +       switch (state) {
> +       case HCI_DEVCOREDUMP_IDLE:
> +               data->cd_info.state = BTMTK_COREDUMP_INIT;
> +               break;
> +       case HCI_DEVCOREDUMP_ACTIVE:
> +               data->cd_info.state = BTMTK_COREDUMP_ACTIVE;
> +               break;
> +       case HCI_DEVCOREDUMP_TIMEOUT:
> +       case HCI_DEVCOREDUMP_ABORT:
> +       case HCI_DEVCOREDUMP_DONE:
> +               data->cd_info.state = BTMTK_COREDUMP_INIT;
> +               btmtk_reset_sync(hdev);
> +               break;
> +       }
> +}

Don't really like where this is going, why can't you just use the
state from devcd?

> +
>  int btmtk_setup_firmware_79xx(struct hci_dev *hdev, const char *fwname,
>                               wmt_cmd_sync_func_t wmt_cmd_sync)
>  {
> @@ -295,6 +351,67 @@ void btmtk_reset_sync(struct hci_dev *hdev)
>  }
>  EXPORT_SYMBOL_GPL(btmtk_reset_sync);
>
> +int btmtk_register_coredump(struct hci_dev *hdev, u32 dev_id,
> +                            const char *name, u32 fw_version)
> +{
> +       struct btmtk_data *data = hci_get_priv(hdev);
> +
> +       if (!IS_ENABLED(CONFIG_DEV_COREDUMP))
> +               return -EOPNOTSUPP;
> +
> +       data->cd_info.dev_id = dev_id;
> +       data->cd_info.fw_version = fw_version;
> +       data->cd_info.state = BTMTK_COREDUMP_INIT;
> +       strncpy(data->cd_info.driver_name, name, MTK_DRIVER_NAME_LEN - 1);

Im not really sure why every devcd is having to store the driver name
as a copy, the driver name is already accessible via
hdev->dev->driver->name.

@Manish Mandlik we might want to fix any code that still is doing
copies of driver name like above.

> +
> +       return hci_devcd_register(hdev, btmtk_coredump, btmtk_coredump_hdr,
> +                                 btmtk_coredump_notify);
> +}
> +EXPORT_SYMBOL_GPL(btmtk_register_coredump);
> +
> +int btmtk_process_coredump(struct hci_dev *hdev, struct sk_buff *skb)
> +{
> +       struct btmtk_data *data = hci_get_priv(hdev);
> +       int err;
> +
> +       if (!IS_ENABLED(CONFIG_DEV_COREDUMP))
> +               return 0;
> +
> +       switch (data->cd_info.state) {
> +       case BTMTK_COREDUMP_DISABLED:
> +               err = -EINVAL;
> +               break;
> +       case BTMTK_COREDUMP_INIT:
> +               err = hci_devcd_init(hdev, MTK_COREDUMP_SIZE);
> +               if (err < 0)
> +                       break;
> +               /* It is supposed coredump can be done within 5 seconds */
> +               schedule_delayed_work(&hdev->dump.dump_timeout,
> +                                     msecs_to_jiffies(5000));
> +               fallthrough;
> +       case BTMTK_COREDUMP_ACTIVE:
> +       default:
> +               err = hci_devcd_append(hdev, skb);
> +               if (err < 0)
> +                       break;
> +
> +               if (skb->len > 12 &&
> +                   !strncmp((char *)&skb->data[skb->len - 13],
> +                            MTK_COREDUMP_END, 12))
> +                       hci_devcd_complete(hdev);
> +
> +               break;
> +       }
> +
> +       if (err < 0) {
> +               data->cd_info.state = BTMTK_COREDUMP_DISABLED;
> +               kfree_skb(skb);
> +       }
> +
> +       return err;
> +}
> +EXPORT_SYMBOL_GPL(btmtk_process_coredump);
> +
>  MODULE_AUTHOR("Sean Wang <sean.wang@mediatek.com>");
>  MODULE_AUTHOR("Mark Chen <mark-yw.chen@mediatek.com>");
>  MODULE_DESCRIPTION("Bluetooth support for MediaTek devices ver " VERSION);
> diff --git a/drivers/bluetooth/btmtk.h b/drivers/bluetooth/btmtk.h
> index 6245662f6ccb..7eb162f0e7aa 100644
> --- a/drivers/bluetooth/btmtk.h
> +++ b/drivers/bluetooth/btmtk.h
> @@ -21,6 +21,10 @@
>  #define MT7921_DLSTATUS 0x7c053c10
>  #define BT_DL_STATE BIT(1)
>
> +#define MTK_DRIVER_NAME_LEN            16
> +#define MTK_COREDUMP_SIZE              (1024 * 1000)
> +#define MTK_COREDUMP_END               "coredump end"
> +
>  enum {
>         BTMTK_WMT_PATCH_DWNLD = 0x1,
>         BTMTK_WMT_TEST = 0x2,
> @@ -119,12 +123,20 @@ struct btmtk_hci_wmt_params {
>         u32 *status;
>  };
>
> +struct btmtk_coredump_info {
> +       char driver_name[MTK_DRIVER_NAME_LEN];
> +       u32 dev_id;
> +       u32 fw_version;
> +       int state;
> +};
> +
>  typedef int (*wmt_cmd_sync_func_t)(struct hci_dev *,
>                                    struct btmtk_hci_wmt_params *);
>
>  typedef int (*btmtk_reset_sync_func_t)(struct hci_dev *, void *);
>
>  struct btmtk_data {
> +       struct btmtk_coredump_info cd_info;
>         btmtk_reset_sync_func_t reset_sync;
>  };
>
> @@ -139,6 +151,11 @@ int btmtk_setup_firmware(struct hci_dev *hdev, const char *fwname,
>                          wmt_cmd_sync_func_t wmt_cmd_sync);
>
>  void btmtk_reset_sync(struct hci_dev *hdev);
> +
> +int btmtk_register_coredump(struct hci_dev *hdev, u32 dev_id, const char *name,
> +                            u32 fw_version);
> +
> +int btmtk_process_coredump(struct hci_dev *hdev, struct sk_buff *skb);
>  #else
>
>  static inline int btmtk_set_bdaddr(struct hci_dev *hdev,
> @@ -162,4 +179,15 @@ static int btmtk_setup_firmware(struct hci_dev *hdev, const char *fwname,
>  static void btmtk_reset_sync(struct hci_dev *hdev)
>  {
>  }
> +
> +static int btmtk_register_coredump(struct hci_dev *hdev, u32 dev_id, const char *name,
> +                            u32 fw_version)
> +{
> +       return -EOPNOTSUPP;
> +}
> +
> +static int btmtk_process_coredump(struct hci_dev *hdev, struct sk_buff *skb)
> +{
> +       return -EOPNOTSUPP;
> +}
>  #endif
> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
> index 034edd8ad777..1c2a0cbcf62e 100644
> --- a/drivers/bluetooth/btusb.c
> +++ b/drivers/bluetooth/btusb.c
> @@ -3035,6 +3035,10 @@ static int btusb_mtk_setup(struct hci_dev *hdev)
>         }
>
>         btmtk_data->reset_sync = btusb_mtk_reset_work;
> +       err = btmtk_register_coredump(hdev, dev_id, btusb_driver.name,
> +                               fw_version);
> +       if (err < 0)
> +               bt_dev_err(hdev, "Failed to register coredump (%d)", err);
>
>         switch (dev_id) {
>         case 0x7663:
> @@ -3189,6 +3193,7 @@ static int btusb_recv_acl_mtk(struct hci_dev *hdev, struct sk_buff *skb)
>  {
>         struct btusb_data *data = hci_get_drvdata(hdev);
>         u16 handle = le16_to_cpu(hci_acl_hdr(skb)->handle);
> +       struct sk_buff *skb_cd;
>
>         switch (handle) {
>         case 0xfc6f:            /* Firmware dump from device */
> @@ -3196,6 +3201,15 @@ static int btusb_recv_acl_mtk(struct hci_dev *hdev, struct sk_buff *skb)
>                  * suspend and thus disable auto-suspend.
>                  */
>                 usb_disable_autosuspend(data->udev);
> +
> +               /* We need to forward the diagnostic packet to userspace daemon
> +                * for backward compatibility, so we have to clone the packet
> +                * extraly for the in-kernel coredump support.
> +                */
> +               skb_cd = skb_clone(skb, GFP_ATOMIC);
> +               if (skb_cd)
> +                       btmtk_process_coredump(hdev, skb_cd);
> +
>                 fallthrough;
>         case 0x05ff:            /* Firmware debug logging 1 */
>         case 0x05fe:            /* Firmware debug logging 2 */
> --
> 2.25.1
>