Date: Thu, 22 Mar 2018 12:02:03 +0000 From: Andrew Turner <andrew@fubar.geek.nz> To: Hans Petter Selasky <hps@selasky.org> Cc: Kyle Evans <kevans@freebsd.org>, src-committers <src-committers@freebsd.org>, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r331306 - head/sys/dev/usb/controller Message-ID: <8722C20F-9581-4C58-98D8-86FD0016BC6B@fubar.geek.nz> In-Reply-To: <00c43a84-893e-cbd8-ff6d-f7a551ae3beb@selasky.org> References: <201803211517.w2LFHsHf007714@repo.freebsd.org> <CACNAnaHCf8paMB3RP1SSnP45xPTSKEcJp-qKyKievLE0E_svWA@mail.gmail.com> <b8627a61-adde-a9b4-8cd1-af9435b9ea92@selasky.org> <898DF1A6-F1D2-474C-92B5-12F65DC71A40@fubar.geek.nz> <00c43a84-893e-cbd8-ff6d-f7a551ae3beb@selasky.org>
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> On 21 Mar 2018, at 21:54, Hans Petter Selasky <hps@selasky.org> wrote:
>=20
> On 03/21/18 17:45, Andrew Turner wrote:
>>> On 21 Mar 2018, at 15:37, Hans Petter Selasky <hps@selasky.org> =
wrote:
>>>=20
>>> On 03/21/18 16:24, Kyle Evans wrote:
>>>>> + {
>>>>> + .ep_end =3D 7,
>>>>> + .ep_fifosz_shift =3D 9,
>>>>> + .ep_fifosz_reg =3D MUSB2_VAL_FIFOSZ_512 | =
MUSB2_MASK_FIFODB,
>>>>> + },
>>>> I'm afraid I'm not familiar with this- why did .ep_fifosz_shift for
>>>> this case drop to 9? frx =3D 10 in the temp < 8 case in the =
removals of
>>>> the following hunks. Mostly curious because the others seemed to =
stay
>>>> the same.
>>>=20
>>> Hi Andrew,
>>>=20
>>> It might be an idea to keep the fifosz_shift at 10, else high-speed =
BULK traffic won't be double buffered, and this might affect =
performance.
>> Should the endpoint 1 size also be fixed? The register has it at 4k, =
but it wasn=E2=80=99t an 8k buffer.
>=20
> No, because High-Speed BULK will only use 512 byte packets, and 4k is =
reserved for isochronous, which doesn't need double buffering at the =
moment.
Ok, in that case should we remove the double buffer flag on endpoint 1? =
The Linux driver seems to always use a 512 byte buffer there, and always =
doubles the offset increment when the double buffer flag is set.
Andrew
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