Return-Path: From: Eric Anholt To: Marcel Holtmann , Loic Poulain Cc: Peter Robinson , "devicetree\@vger.kernel.org" , Johan Hedberg , Scott Branden , Ray Jui , "open list\:BLUETOOTH DRIVERS" , Rob Herring , linux-rpi-kernel@lists.infradead.org Subject: Re: [PATCH v3 2/3] ARM: dts: bcm2837-rpi-3-b: Add bcm43438 as serial slave In-Reply-To: <8CF7E37E-BF1C-4E32-AF3A-E44BA2E5A2B9@holtmann.org> References: <1502102366-2760-1-git-send-email-loic.poulain@gmail.com> <1502102366-2760-2-git-send-email-loic.poulain@gmail.com> <8186E2A3-D0AC-498F-8229-78862D363F78@holtmann.org> <392e6d51-33d6-1585-6582-1397a0c64852@gmail.com> <161632C7-EBBF-47F5-86DC-453E10395B54@holtmann.org> <0C198B33-8CB6-4D6A-B89F-35D3CD771135@holtmann.org> <92579650-5eb0-cdf2-405a-7c5be9c54770@gmail.com> <8CF7E37E-BF1C-4E32-AF3A-E44BA2E5A2B9@holtmann.org> Date: Thu, 17 Aug 2017 09:21:12 -0700 Message-ID: <87shgqgo7b.fsf@eliezer.anholt.net> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature" List-ID: --=-=-= Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Marcel Holtmann writes: > Hi Loic, > >>>>> < HCI Command: Broadcom Write UART Clock Setting (0x3f|0x0045) plen 1 >>>>> 01 . >>>>>> HCI Event: Command Complete (0x0e) plen 4 >>>>> Broadcom Write UART Clock Setting (0x3f|0x0045) ncmd 1 >>>>> Status: Unknown HCI Command (0x01) >>>>>=20 >>>>> And I am seeing fun stuff like failed frame assembly. >>>>>=20 >>>>> [ 888.687594] Bluetooth: hci0: BCM: chip id 94 >>>>> [ 888.687821] Bluetooth: hci0: BCM43430A1 (001.002.009) build 0182 >>>>> [ 892.059023] Bluetooth: hci0: Frame reassembly failed (-84) >>>>> [ 892.316936] Bluetooth: hci0: BCM: failed to write clock (-56) >>>>> [ 892.429478] Bluetooth: hci0: BCM (001.002.009) build 0182 >>>>>=20 >>>>> Actually not providing the firmware makes the controller work. It how= ever is stuck ad AA:AA:.. default address. Providing the firmware turns the= address active. However then it never completes. >>>> I've tried on and off to get the BT working, there seems to lots of >>>> options and bits needed including some patches to the bluez [1] stuff >>>> but between not quite upstream kernel bits and numerous distros all >>>> doing it slightly differently I've never got it to work well. >>>>=20 >>>> The yocto [1] bits seem fairly representative of some the patches >>>> flying around "to get it working" although I'm not sure how many of >>>> these are actually required and how many are superfluous with this >>>> patch set. There seems to be a firmware required that's not >>>> distributed with linux-firmware which would also be nice to resolve. >>> Non of these Yocto patches are actually needed. The culprit is the .ope= r_speed setting to be 4Mbps. Once you reduce that to 921600 thing will star= t to work smoothly. I sent a patch that takes the .oper_speed out completel= y and only applies it for the ACPI based devices where we know that it work= s. >>>=20 >>> With my patch and the right DT entries for uart0 it actually works with= =E2=80=9Cbtattach -B /dev/ttyAMA0 -P bcm=E2=80=9D. It will load the firmwa= re, configure it and head towards the right path. >>>=20 >>> Obviously btattach is only an interim step here. Loic=E2=80=99s patches= for serdev integration and changing the DT to expose uart0 as serial-slave= for Bluetooth is the right approach. Once Loic=E2=80=99s resends the patch= es we can get them into bluetooth-next and start merging these towards upst= ream. After that, Bluetooth should work just out of the box like with any U= SB dongle. >>>=20 >>> And the Yocto patches should be abandoned. If using H:5 (aka 3-Wire) in= stead of H:4 is possible, we could consider it, but as long as the UART wir= ing doesn=E2=80=99t cause any bit errors, it is not worth it. >>>=20 >>> That said, I do see a "Bluetooth: hci0: Frame reassembly failed (-84)= =E2=80=9D error. I need to figure out where that is. Frankly we really need= to hexdump the packet when this happens. >>>=20 >>=20 >> I also meet this Frame reassembly failure, Seems we receive a 0x00 byte = from the controller (unknown pkt type). > > that means adding something like this will silence it. > > +#define BCM_RECV_NULL \ > + .type =3D 0x00, \ > + .hlen =3D 0, \ > + .loff =3D 0, \ > + .lsize =3D 0, \ > + .maxlen =3D 0 > + > +static int bcm_recv_null(struct hci_dev *hdev, struct sk_buff *skb) > +{ > + kfree_skb(skb); > + return 0; > +} > + > static const struct h4_recv_pkt bcm_recv_pkts[] =3D { > { H4_RECV_ACL, .recv =3D hci_recv_frame }, > { H4_RECV_SCO, .recv =3D hci_recv_frame }, > { H4_RECV_EVENT, .recv =3D hci_recv_frame }, > { BCM_RECV_LM_DIAG, .recv =3D hci_recv_diag }, > + { BCM_RECV_NULL, .recv =3D bcm_recv_null }, > }; > > It does silence it indeed. Maybe this is some of their markers to > ensure that the baud rate change worked. Or it is the indication that > the reset completed. Do you happen to know between which commands we > receive it? > >> Regarding the speed, I'm unable to reach 3Mbps, I selected 921600 >> because this is the baudrate used by raspbian bt script. > > That is the same I experienced. The 921600 works fine, but trying > 3Mbps doesn=E2=80=99t. However it seems with hciattach you can crank it u= p to > 3Mpbs somehow. Maybe the delay is just to short for the UART switching > in that case. > >> Maybe they had some issues at higher speed (empirical value ?), >> However 2Mbps seems ok on my side (need to double check/adjust). > > We have to make it a DT max-speed param anyway. So I am not that > worried. > >> In a second step, need to check If we can use hardware flow control, >> I heard that pin 16&17 are routed to the bcm RTS/CTS. Since there is >> no DMA usage, it could help. The BT's CTS/RTS are tied to 3v3/ground. > Eric, any chance you can dig out the recommendation for the Bluetooth > controller usage? I would also like to see the recommended PCM > settings for this hardware. It bet it is somehow wired up to the sound > controller. BT's PCM is connected to gpio 28-31 on the pi3, which you can pinmux to the i2s controller (pcm_gpio28 pin group). I'm not clear on what you're asking for, or where I would go to find anything else. However, for integration stuff on the board, Phil, Dom, and Gordon at RPi are likely to know more. --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEE/JuuFDWp9/ZkuCBXtdYpNtH8nugFAlmVwngACgkQtdYpNtH8 nuhQGRAAjtk49zjZWrOllMR1fZ2M3kK3yw0NalvT1BzsgkTet+TIb6d+bU3rQQfm RpVgLnRG5Efq//ghx9zlMhI+q7bh9IoeLflIUWNJE66aCh31nZ6hubwPavKH7mLn +cmQTLfarh/Ql8kbWfthUGTijpMc9QT3G0n5NKpVMkVVZmasPwR1zttSFgQKNbIi EyermY/7UWhARADA2CELUyw8y8iaaVFRZZkKLT7kSArU1ZwUUZKdccZn6mhRskUn fIUosh00vXtqJ87SWwZDlPu9ndmBLpHGsFzYJdy1KVyMoUS5iMcggPJsCjDqnYxA 1yqp5ZDlzXR0NeyiqvtY4G6bQg8xyXn5W/s0B6C7vBgT/720lODyfPVQs+jc+Uql 8YsR+KYZj7zPzzW3L7EjKzwiLSJiT6p+kxV7lb3WjUB1g7Ai+qXazFceV2YNphE+ R6R5y/Ht/DHIZLpgLxi1nBxRAfThTo0JkyDBJDO9o5ATwt62uyHxqEwhgUS4N8mc nqZlq3sfTJOxoGZlD8qlvJsqHmSXggz3HTsqtXMX59JYtyrB+aTo3Ag+l5b2COwP QdofovekmMIcl6/X+JjwZmtXmwAUCIrA6GkgS7D7L+HyAW2v5tyqqAs2PPbUdUEb 8jBu/mZ8VFsHxmGbXGf70ym1XaBBbRInyOwFaO7IxUf9rG6s/00= =yr7F -----END PGP SIGNATURE----- --=-=-=--