diff mbox series

[v2,5/5] Bluetooth: hci_bcm: Increase host baudrate for CYW55572 in autobaud mode

Message ID c0ac87d9f7072de6ad8ea7c9d306eacfbb4ef2c9.1656583541.git.hakan.jansson@infineon.com (mailing list archive)
State Awaiting Upstream
Headers show
Series Bluetooth: hci_bcm: Improve FW load time on CYW55572 | expand

Checks

Context Check Description
netdev/tree_selection success Not a local patch

Commit Message

Hakan Jansson June 30, 2022, 12:53 p.m. UTC
Add device specific data for max baudrate in autobaud mode. This allows the
host to use a baudrate higher than "init speed" when loading FW in autobaud
mode.

The device specific max baudrate in autobaud mode for CYW55572 is set to
921600 bps. Devices without device specific max baudrate in autobaud mode
will use init speed as before. If no device specific init speed has been
specified, it will default to the bcm_proto default 115200 bps.

The increased baud rate improves FW load time. The exact load time will
depend on the specific system and FW being used. As a rough indication,
the FW load time dropped from ~9s @ 115.2kbps to ~1.7s @ 921.6kbps in one
test.

Signed-off-by: Hakan Jansson <hakan.jansson@infineon.com>
---
V1 -> V2:
  - Add actual baud rates and example FW load time in commit message

 drivers/bluetooth/hci_bcm.c | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

Comments

Linus Walleij July 11, 2022, 8:34 a.m. UTC | #1
On Thu, Jun 30, 2022 at 2:55 PM Hakan Jansson
<hakan.jansson@infineon.com> wrote:

> Add device specific data for max baudrate in autobaud mode. This allows the
> host to use a baudrate higher than "init speed" when loading FW in autobaud
> mode.
>
> The device specific max baudrate in autobaud mode for CYW55572 is set to
> 921600 bps. Devices without device specific max baudrate in autobaud mode
> will use init speed as before. If no device specific init speed has been
> specified, it will default to the bcm_proto default 115200 bps.
>
> The increased baud rate improves FW load time. The exact load time will
> depend on the specific system and FW being used. As a rough indication,
> the FW load time dropped from ~9s @ 115.2kbps to ~1.7s @ 921.6kbps in one
> test.
>
> Signed-off-by: Hakan Jansson <hakan.jansson@infineon.com>

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij
diff mbox series

Patch

diff --git a/drivers/bluetooth/hci_bcm.c b/drivers/bluetooth/hci_bcm.c
index 0ae627c293c5..d7e0b75db8a6 100644
--- a/drivers/bluetooth/hci_bcm.c
+++ b/drivers/bluetooth/hci_bcm.c
@@ -53,10 +53,12 @@ 
  * struct bcm_device_data - device specific data
  * @no_early_set_baudrate: Disallow set baudrate before driver setup()
  * @drive_rts_on_open: drive RTS signal on ->open() when platform requires it
+ * @max_autobaud_speed: max baudrate supported by device in autobaud mode
  */
 struct bcm_device_data {
 	bool	no_early_set_baudrate;
 	bool	drive_rts_on_open;
+	u32	max_autobaud_speed;
 };
 
 /**
@@ -100,6 +102,7 @@  struct bcm_device_data {
  * @drive_rts_on_open: drive RTS signal on ->open() when platform requires it
  * @pcm_int_params: keep the initial PCM configuration
  * @use_autobaud_mode: start Bluetooth device in autobaud mode
+ * @max_autobaud_speed: max baudrate supported by device in autobaud mode
  */
 struct bcm_device {
 	/* Must be the first member, hci_serdev.c expects this. */
@@ -139,6 +142,7 @@  struct bcm_device {
 	bool			drive_rts_on_open;
 	bool			use_autobaud_mode;
 	u8			pcm_int_params[5];
+	u32			max_autobaud_speed;
 };
 
 /* generic bcm uart resources */
@@ -479,7 +483,10 @@  static int bcm_open(struct hci_uart *hu)
 		else if (bcm->dev->drive_rts_on_open)
 			hci_uart_set_flow_control(hu, true);
 
-		hu->init_speed = bcm->dev->init_speed;
+		if (bcm->dev->use_autobaud_mode && bcm->dev->max_autobaud_speed)
+			hu->init_speed = min(bcm->dev->oper_speed, bcm->dev->max_autobaud_speed);
+		else
+			hu->init_speed = bcm->dev->init_speed;
 
 		/* If oper_speed is set, ldisc/serdev will set the baudrate
 		 * before calling setup()
@@ -585,8 +592,8 @@  static int bcm_setup(struct hci_uart *hu)
 		return 0;
 
 	/* Init speed if any */
-	if (hu->init_speed)
-		speed = hu->init_speed;
+	if (bcm->dev && bcm->dev->init_speed)
+		speed = bcm->dev->init_speed;
 	else if (hu->proto->init_speed)
 		speed = hu->proto->init_speed;
 	else
@@ -1519,6 +1526,7 @@  static int bcm_serdev_probe(struct serdev_device *serdev)
 
 	data = device_get_match_data(bcmdev->dev);
 	if (data) {
+		bcmdev->max_autobaud_speed = data->max_autobaud_speed;
 		bcmdev->no_early_set_baudrate = data->no_early_set_baudrate;
 		bcmdev->drive_rts_on_open = data->drive_rts_on_open;
 	}
@@ -1542,6 +1550,10 @@  static struct bcm_device_data bcm43438_device_data = {
 	.drive_rts_on_open = true,
 };
 
+static struct bcm_device_data cyw55572_device_data = {
+	.max_autobaud_speed = 921600,
+};
+
 static const struct of_device_id bcm_bluetooth_of_match[] = {
 	{ .compatible = "brcm,bcm20702a1" },
 	{ .compatible = "brcm,bcm4329-bt" },
@@ -1554,7 +1566,7 @@  static const struct of_device_id bcm_bluetooth_of_match[] = {
 	{ .compatible = "brcm,bcm4349-bt", .data = &bcm43438_device_data },
 	{ .compatible = "brcm,bcm43540-bt", .data = &bcm4354_device_data },
 	{ .compatible = "brcm,bcm4335a0" },
-	{ .compatible = "infineon,cyw55572-bt" },
+	{ .compatible = "infineon,cyw55572-bt", .data = &cyw55572_device_data },
 	{ },
 };
 MODULE_DEVICE_TABLE(of, bcm_bluetooth_of_match);