[PATCH v1] Bluetooth: btusb: Add WCN6855 devcoredump support

[Tim Jiang]

WCN6855 will report memdump via ACL data or HCI event when
it get crashed, so we collect memdump to debug firmware.

Signed-off-by: Tim Jiang <quic_tjiang@xxxxxxxxxxx>
---
 drivers/bluetooth/btusb.c | 221 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 221 insertions(+)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 2303b0a66323..ecc346d8b2ea 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -752,6 +752,7 @@ static const struct dmi_system_id btusb_needs_reset_resume_table[] = {
 #define BTUSB_WAKEUP_AUTOSUSPEND	14
 #define BTUSB_USE_ALT3_FOR_WBS	15
 #define BTUSB_ALT6_CONTINUOUS_TX	16
+#define BTUSB_HW_SSR_ACTIVE	17
 
 struct btusb_data {
 	struct hci_dev       *hdev;
@@ -904,6 +905,11 @@ static void btusb_qca_cmd_timeout(struct hci_dev *hdev)
 	struct btusb_data *data = hci_get_drvdata(hdev);
 	struct gpio_desc *reset_gpio = data->reset_gpio;
 
+	if (test_bit(BTUSB_HW_SSR_ACTIVE, &data->flags)) {
+		bt_dev_info(hdev, "Defer cmd_timeout due to dump active");
+		return;
+	}
+
 	if (++data->cmd_timeout_cnt < 5)
 		return;
 
@@ -3294,6 +3300,213 @@ static int btusb_set_bdaddr_wcn6855(struct hci_dev *hdev,
 	return 0;
 }
 
+#define QCA_MEMDUMP_ACL_HANDLE 0x2EDD
+#define QCA_MEMDUMP_SIZE_MAX  0x100000
+#define QCA_MEMDUMP_VSE_CLASS 0x01
+#define QCA_MEMDUMP_MSG_TYPE 0x08
+struct qca_dump_hdr {
+	u8 vse_class;
+	u8 msg_type;
+	__le16 seqno;
+	u8 reserved;
+	union {
+		u8 data[0];
+		struct {
+			__le32 ram_dump_size;
+			u8 data0[0];
+		} __packed;
+	};
+} __packed;
+
+struct qca_dump_info {
+	/* fields for dump collection */
+	u16 id_vendor;
+	u16 id_product;
+	u32 fw_version;
+	u32 controller_id;
+	u32 ram_dump_size;
+	u32 ram_dump_offs;
+	u16 ram_dump_seqno;
+};
+
+static struct qca_dump_info qca_dump = {0};
+
+static void btusb_dump_hdr_qca(struct hci_dev *hdev, struct sk_buff *skb)
+{
+	char buf[128];
+
+	snprintf(buf, sizeof(buf), "Controller Name: 0x%x\n",
+			qca_dump.controller_id);
+	skb_put_data(skb, buf, strlen(buf));
+
+	snprintf(buf, sizeof(buf), "Firmware Version: 0x%x\n",
+			qca_dump.fw_version);
+	skb_put_data(skb, buf, strlen(buf));
+
+	snprintf(buf, sizeof(buf), "Driver: %s\nVendor: qca\n",
+			btusb_driver.name);
+	skb_put_data(skb, buf, strlen(buf));
+
+	snprintf(buf, sizeof(buf), "VID: 0x%x\nPID:0x%x\n",
+			qca_dump.id_vendor, qca_dump.id_product);
+	skb_put_data(skb, buf, strlen(buf));
+
+	snprintf(buf, sizeof(buf), "Lmp Subversion: 0x%x\n",
+			hdev->lmp_subver);
+	skb_put_data(skb, buf, strlen(buf));
+}
+
+static void btusb_coredump_qca(struct hci_dev *hdev)
+{
+	static const u8 param[] = { 0x26 };
+	struct sk_buff *skb;
+
+	skb = __hci_cmd_sync(hdev, 0xfc0c, 1, param, HCI_CMD_TIMEOUT);
+	if (IS_ERR(skb))
+		bt_dev_err(hdev, "%s: triggle crash failed (%ld)", __func__, PTR_ERR(skb));
+	kfree_skb(skb);
+}
+
+/*
+ * ==0: not a dump pkt.
+ * < 0: fails to handle a dump pkt
+ * > 0: otherwise.
+ */
+static int handle_dump_pkt_qca(struct hci_dev *hdev, struct sk_buff *skb)
+{
+	int ret = 0;
+	u8 pkt_type;
+	u8 *sk_ptr;
+	unsigned int sk_len;
+	u16 seqno;
+	u32 ram_dump_size;
+
+	struct hci_event_hdr *event_hdr;
+	struct hci_acl_hdr *acl_hdr;
+	struct qca_dump_hdr *dump_hdr;
+	struct btusb_data *btdata = hci_get_drvdata(hdev);
+	struct usb_device *udev = btdata->udev;
+
+	pkt_type = hci_skb_pkt_type(skb);
+	sk_ptr = skb->data;
+	sk_len = skb->len;
+
+	if (pkt_type == HCI_ACLDATA_PKT) {
+		acl_hdr = hci_acl_hdr(skb);
+		if (le16_to_cpu(acl_hdr->handle) != QCA_MEMDUMP_ACL_HANDLE)
+			return 0;
+		sk_ptr += HCI_ACL_HDR_SIZE;
+		sk_len -= HCI_ACL_HDR_SIZE;
+		event_hdr = (struct hci_event_hdr *)sk_ptr;
+	} else {
+		event_hdr = hci_event_hdr(skb);
+	}
+
+	if (event_hdr->evt != HCI_VENDOR_PKT)
+		return 0;
+	if (event_hdr->plen != (sk_len - HCI_EVENT_HDR_SIZE))
+		return 0;
+	sk_ptr += HCI_EVENT_HDR_SIZE;
+	sk_len -= HCI_EVENT_HDR_SIZE;
+
+	if (sk_len < offsetof(struct qca_dump_hdr, data))
+		return 0;
+	dump_hdr = (struct qca_dump_hdr *)sk_ptr;
+	if ((dump_hdr->vse_class != QCA_MEMDUMP_VSE_CLASS)
+	    || (dump_hdr->msg_type != QCA_MEMDUMP_MSG_TYPE))
+		return 0;
+
+	/*it is dump pkt now*/
+	ret = 1;
+	seqno = le16_to_cpu(dump_hdr->seqno);
+	if (seqno == 0) {
+		set_bit(BTUSB_HW_SSR_ACTIVE, &btdata->flags);
+		ram_dump_size = le32_to_cpu(dump_hdr->ram_dump_size);
+		if (!ram_dump_size || (ram_dump_size > QCA_MEMDUMP_SIZE_MAX)) {
+			ret = -EILSEQ;
+			bt_dev_err(hdev, "Invalid memdump size(%u)",
+				   ram_dump_size);
+			goto out;
+		}
+
+		ret = hci_devcd_init(hdev, ram_dump_size);
+		if (ret < 0) {
+			bt_dev_err(hdev, "memdump init error(%d)", ret);
+			goto out;
+		}
+		ret = 1;
+
+		qca_dump.ram_dump_size = ram_dump_size;
+		qca_dump.ram_dump_offs = 0;
+		qca_dump.ram_dump_seqno = 0;
+		sk_ptr += offsetof(struct qca_dump_hdr, data0);
+		sk_len -= offsetof(struct qca_dump_hdr, data0);
+
+		usb_disable_autosuspend(udev);
+		bt_dev_info(hdev, "%s memdump size(%u)\n",
+			    (pkt_type == HCI_ACLDATA_PKT) ? "ACL" : "event",
+			    ram_dump_size);
+	} else {
+		sk_ptr += offsetof(struct qca_dump_hdr, data);
+		sk_len -= offsetof(struct qca_dump_hdr, data);
+	}
+
+	if (!qca_dump.ram_dump_size) {
+		ret = -EINVAL;
+		bt_dev_err(hdev, "memdump is not active");
+		goto out;
+	}
+
+	if ((seqno != qca_dump.ram_dump_seqno) && (seqno != 0xFFFF)) {
+		ret = -EILSEQ;
+		bt_dev_err(hdev,
+			   "expected memdump seqno(%u) is not received(%u)\n",
+			   qca_dump.ram_dump_seqno, seqno);
+		hci_devcd_abort(hdev);
+		goto out;
+	}
+
+	skb_pull(skb, skb->len - sk_len);
+	hci_devcd_append(hdev, skb);
+	qca_dump.ram_dump_offs += sk_len;
+	qca_dump.ram_dump_seqno++;
+	if (seqno != 0xFFFF)
+		return ret;
+	hci_devcd_complete(hdev);
+
+out:
+	if (qca_dump.ram_dump_size) {
+		usb_enable_autosuspend(udev);
+		bt_dev_info(hdev,
+				"memdump Done: pkts(%u), dumped(%u)/total(%u)\n",
+				qca_dump.ram_dump_seqno, qca_dump.ram_dump_offs,
+				qca_dump.ram_dump_size);
+	}
+	qca_dump.ram_dump_size = 0;
+	qca_dump.ram_dump_offs = 0;
+	qca_dump.ram_dump_seqno = 0;
+	clear_bit(BTUSB_HW_SSR_ACTIVE, &btdata->flags);
+
+	if (ret < 0)
+		kfree_skb(skb);
+	return ret;
+}
+
+static int btusb_recv_acl_qca(struct hci_dev *hdev, struct sk_buff *skb)
+{
+	if (handle_dump_pkt_qca(hdev, skb))
+		return 0;
+	return hci_recv_frame(hdev, skb);
+}
+
+static int btusb_recv_evt_qca(struct hci_dev *hdev, struct sk_buff *skb)
+{
+	if (handle_dump_pkt_qca(hdev, skb))
+		return 0;
+	return hci_recv_frame(hdev, skb);
+}
+
+
 #define QCA_DFU_PACKET_LEN	4096
 
 #define QCA_GET_TARGET_VERSION	0x09
@@ -3628,6 +3841,9 @@ static int btusb_setup_qca(struct hci_dev *hdev)
 	if (err < 0)
 		return err;
 
+	qca_dump.fw_version = le32_to_cpu(ver.patch_version);
+	qca_dump.controller_id = le32_to_cpu(ver.rom_version);
+
 	if (!(status & QCA_SYSCFG_UPDATED)) {
 		err = btusb_setup_qca_load_nvm(hdev, &ver, info);
 		if (err < 0)
@@ -4117,6 +4333,11 @@ static int btusb_probe(struct usb_interface *intf,
 	}
 
 	if (id->driver_info & BTUSB_QCA_WCN6855) {
+		qca_dump.id_vendor = id->idVendor;
+		qca_dump.id_product = id->idProduct;
+		data->recv_event = btusb_recv_evt_qca;
+		data->recv_acl = btusb_recv_acl_qca;
+		hci_devcd_register(hdev, btusb_coredump_qca, btusb_dump_hdr_qca, NULL);
 		data->setup_on_usb = btusb_setup_qca;
 		hdev->shutdown = btusb_shutdown_qca;
 		hdev->set_bdaddr = btusb_set_bdaddr_wcn6855;
-- 
2.17.1