[PATCH 2/2] Bluetooth: btusb: Add Intel devcoredump support

From: Manish Mandlik
Date: Sun Mar 20 2022 - 21:34:20 EST


From: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>

Intercept debug exception events from the controller and put them into
a devcoredump using hci devcoredump APIs. The debug exception contains
data in a TLV format and it will be parsed in userspace.

Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>
Signed-off-by: Manish Mandlik <mmandlik@xxxxxxxxxx>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>
Reviewed-by: Chethan Tumkur Narayan <chethan.tumkur.narayan@xxxxxxxxx>
---

drivers/bluetooth/btintel.c | 60 +++++++++++++++++++++++++++++++++++++
drivers/bluetooth/btintel.h | 14 +++++++++
drivers/bluetooth/btusb.c | 47 +++++++++++++++++++++++++----
3 files changed, 115 insertions(+), 6 deletions(-)

diff --git a/drivers/bluetooth/btintel.c b/drivers/bluetooth/btintel.c
index 06514ed66022..9ac7a4441b38 100644
--- a/drivers/bluetooth/btintel.c
+++ b/drivers/bluetooth/btintel.c
@@ -32,6 +32,11 @@ struct cmd_write_boot_params {
u8 fw_build_yy;
} __packed;

+#define DRIVER_NAME_LEN 16
+static char driver_name[DRIVER_NAME_LEN];
+static u8 hw_variant;
+static u32 fw_build_num;
+
int btintel_check_bdaddr(struct hci_dev *hdev)
{
struct hci_rp_read_bd_addr *bda;
@@ -304,6 +309,9 @@ int btintel_version_info(struct hci_dev *hdev, struct intel_version *ver)
return -EINVAL;
}

+ hw_variant = ver->hw_variant;
+ fw_build_num = ver->fw_build_num;
+
bt_dev_info(hdev, "%s revision %u.%u build %u week %u %u",
variant, ver->fw_revision >> 4, ver->fw_revision & 0x0f,
ver->fw_build_num, ver->fw_build_ww,
@@ -497,6 +505,9 @@ static int btintel_version_info_tlv(struct hci_dev *hdev,
return -EINVAL;
}

+ hw_variant = INTEL_HW_VARIANT(version->cnvi_bt);
+ fw_build_num = version->build_num;
+
bt_dev_info(hdev, "%s timestamp %u.%u buildtype %u build %u", variant,
2000 + (version->timestamp >> 8), version->timestamp & 0xff,
version->build_type, version->build_num);
@@ -1391,6 +1402,55 @@ int btintel_set_quality_report(struct hci_dev *hdev, bool enable)
}
EXPORT_SYMBOL_GPL(btintel_set_quality_report);

+static int btintel_dmp_hdr(struct hci_dev *hdev, char *buf, size_t size)
+{
+ char *ptr = buf;
+ size_t rem = size;
+ size_t read = 0;
+
+ read = snprintf(ptr, rem, "Controller Name: 0x%X\n", hw_variant);
+ rem -= read;
+ ptr += read;
+
+ read = snprintf(ptr, rem, "Firmware Version: 0x%X\n", fw_build_num);
+ rem -= read;
+ ptr += read;
+
+ read = snprintf(ptr, rem, "Driver: %s\n", driver_name);
+ rem -= read;
+ ptr += read;
+
+ read = snprintf(ptr, rem, "Vendor: Intel\n");
+ rem -= read;
+ ptr += read;
+
+ return size - rem;
+}
+
+int btintel_register_devcoredump_support(struct hci_dev *hdev,
+ const char *driver)
+{
+ struct intel_debug_features features;
+ int err;
+
+ err = btintel_read_debug_features(hdev, &features);
+ if (err) {
+ bt_dev_info(hdev, "Error reading debug features");
+ return err;
+ }
+
+ if (!(features.page1[0] & 0x3f)) {
+ bt_dev_info(hdev, "Telemetry exception format not supported");
+ return -EOPNOTSUPP;
+ }
+
+ strncpy(driver_name, driver, DRIVER_NAME_LEN);
+ hci_devcoredump_register(hdev, btintel_dmp_hdr, NULL);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(btintel_register_devcoredump_support);
+
static const struct firmware *btintel_legacy_rom_get_fw(struct hci_dev *hdev,
struct intel_version *ver)
{
diff --git a/drivers/bluetooth/btintel.h b/drivers/bluetooth/btintel.h
index e0060e58573c..785c63cc6c1d 100644
--- a/drivers/bluetooth/btintel.h
+++ b/drivers/bluetooth/btintel.h
@@ -137,6 +137,12 @@ struct intel_offload_use_cases {
__u8 preset[8];
} __packed;

+#define INTEL_TLV_TYPE_ID 0x1
+
+#define INTEL_TLV_SYSTEM_EXCEPTION 0x0
+#define INTEL_TLV_FATAL_EXCEPTION 0x1
+#define INTEL_TLV_DEBUG_EXCEPTION 0x2
+
#define INTEL_HW_PLATFORM(cnvx_bt) ((u8)(((cnvx_bt) & 0x0000ff00) >> 8))
#define INTEL_HW_VARIANT(cnvx_bt) ((u8)(((cnvx_bt) & 0x003f0000) >> 16))
#define INTEL_CNVX_TOP_TYPE(cnvx_top) ((cnvx_top) & 0x00000fff)
@@ -206,6 +212,8 @@ int btintel_read_boot_params(struct hci_dev *hdev,
struct intel_boot_params *params);
int btintel_download_firmware(struct hci_dev *dev, struct intel_version *ver,
const struct firmware *fw, u32 *boot_param);
+int btintel_register_devcoredump_support(struct hci_dev *hdev,
+ const char *driver);
int btintel_configure_setup(struct hci_dev *hdev);
void btintel_bootup(struct hci_dev *hdev, const void *ptr, unsigned int len);
void btintel_secure_send_result(struct hci_dev *hdev,
@@ -302,6 +310,12 @@ static inline void btintel_secure_send_result(struct hci_dev *hdev,
{
}

+static int btintel_register_devcoredump_support(struct hci_dev *hdev,
+ const char *driver)
+{
+ return -EOPNOTSUPP;
+}
+
static inline int btintel_set_quality_report(struct hci_dev *hdev, bool enable)
{
return -ENODEV;
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 50df417207af..42a3d90180a4 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -2155,16 +2155,42 @@ static int btusb_recv_bulk_intel(struct btusb_data *data, void *buffer,
return btusb_recv_bulk(data, buffer, count);
}

+static int btusb_intel_diagnostics(struct hci_dev *hdev, struct sk_buff *skb)
+{
+ struct intel_tlv *tlv = (void *)&skb->data[5];
+
+ /* The first event is always an event type TLV */
+ if (tlv->type != INTEL_TLV_TYPE_ID)
+ goto recv_frame;
+
+ switch (tlv->val[0]) {
+ case INTEL_TLV_SYSTEM_EXCEPTION:
+ case INTEL_TLV_FATAL_EXCEPTION:
+ case INTEL_TLV_DEBUG_EXCEPTION:
+ /* Generate devcoredump from exception */
+ if (!hci_devcoredump_init(hdev, skb->len)) {
+ hci_devcoredump_append(hdev, skb);
+ hci_devcoredump_complete(hdev);
+ return 0;
+ }
+ break;
+ }
+
+recv_frame:
+ return hci_recv_frame(hdev, skb);
+}
+
static int btusb_recv_event_intel(struct hci_dev *hdev, struct sk_buff *skb)
{
- if (btintel_test_flag(hdev, INTEL_BOOTLOADER)) {
- struct hci_event_hdr *hdr = (void *)skb->data;
+ struct hci_event_hdr *hdr = (void *)skb->data;
+ const char diagnostics_hdr[] = { 0x87, 0x80, 0x03 };

- if (skb->len > HCI_EVENT_HDR_SIZE && hdr->evt == 0xff &&
- hdr->plen > 0) {
- const void *ptr = skb->data + HCI_EVENT_HDR_SIZE + 1;
- unsigned int len = skb->len - HCI_EVENT_HDR_SIZE - 1;
+ if (skb->len > HCI_EVENT_HDR_SIZE && hdr->evt == 0xff &&
+ hdr->plen > 0) {
+ const void *ptr = skb->data + HCI_EVENT_HDR_SIZE + 1;
+ unsigned int len = skb->len - HCI_EVENT_HDR_SIZE - 1;

+ if (btintel_test_flag(hdev, INTEL_BOOTLOADER)) {
switch (skb->data[2]) {
case 0x02:
/* When switching to the operational firmware
@@ -2183,6 +2209,15 @@ static int btusb_recv_event_intel(struct hci_dev *hdev, struct sk_buff *skb)
break;
}
}
+
+ /* Handle all diagnostics events separately. May still call
+ * hci_recv_frame.
+ */
+ if (len >= sizeof(diagnostics_hdr) &&
+ memcmp(&skb->data[2], diagnostics_hdr,
+ sizeof(diagnostics_hdr)) == 0) {
+ return btusb_intel_diagnostics(hdev, skb);
+ }
}

return hci_recv_frame(hdev, skb);
--
2.35.1.894.gb6a874cedc-goog