Date: Wed, 5 Sep 2018 12:56:19 -0600 From: Warner Losh <imp@bsdimp.com> To: Dimitry Andric <dim@freebsd.org> Cc: Lev Serebryakov <lev@freebsd.org>, FreeBSD Hackers <freebsd-hackers@freebsd.org>, Allan Jude <allanjude@freebsd.org> Subject: Re: Is here way to have 9600+ serial console and see boot0 message? Message-ID: <CANCZdfqMfQ378z4iLbNzLxZwMreoAoXKuLE-RnMEZZJq3UpdRA@mail.gmail.com> In-Reply-To: <D6BAE4EA-2926-4000-93E2-DAD7689DFC9D@FreeBSD.org> References: <ac3fe50c-d9a0-96ba-28f0-84ffca8e4cd3@FreeBSD.org> <14cd401a-660c-1a3a-8d80-677a42727146@freebsd.org> <0bc33818-641c-07db-194b-66fd1eb30c55@FreeBSD.org> <D6BAE4EA-2926-4000-93E2-DAD7689DFC9D@FreeBSD.org>
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On Wed, Sep 5, 2018, 12:16 PM Dimitry Andric <dim@freebsd.org> wrote: > On 5 Sep 2018, at 19:22, Lev Serebryakov <lev@FreeBSD.org> wrote: > > > > On 05.09.2018 20:19, Allan Jude wrote: > > > >>> I want to have my serial console 115200 (of course), *including* BIOS > >>> redirection (which goes before boot0sio). > >>> > >>> But boot0sio supports only speeds up to 9600 (due to int 14h > limitations). > >>> > >>> Is it possible to solve this clash somehow? > >> > >> /boot/loader reads /boot.config where you can put -S115200 > > I think, /boot/boot reads /boot.config, and it works for me. > > > > My question is somewhat more tricky: I have 115200 BEFORE boot0sio > > (from BIOS) and I have 115200 AFTER boot0sio (from /boot/boot and > > /boot/loader later). And I want to see "F1 / F2" boot selection from > > boot0sio. > > Recompile stand/i386 with BOOT_BOOT0_COMCONSOLE_SPEED=115200, I would > normally say, but apparently stand/i386/boot0 is limited to a maximum > of 9600 baud. This looks like a BIOS int 0x14 limitation. :( > Only way around this I know is to recede boot0sio to go right to the uart... I tried this years ago, but overflowed 512 limits... Warner >
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