On Fri, Apr 01, 2016 at 01:07:55PM +0200, Gerd Hoffmann wrote:
> On Fr, 2016-04-01 at 11:17 +0100, Richard W.M. Jones wrote:
> > On Fri, Apr 01, 2016 at 11:18:30AM +0200, Gerd Hoffmann wrote:
> > > Hi,
> > >
> > > > I wonder how we can make use of this in qemu and downstream distros?
> > > > Can we have a bios-min.bin which is used with -kernel boots?
> > >
> > > We already build two seabios roms: one full featued and one slightly
> > > stripped down to keep it below 128k, for backward compatibility with old
> > > machine types.
> > >
> > > Adding a third config for -kernel boot should be easy. For that use
> > > case we can probably also turn on seabios logging to the serial console
> > > and drop sgabios. We don't need input (no boot menu) and we also don't
> > > need to hook into int10 (no grub/ipxe using that for output).
> >
> > SeaBIOS logging is slow (or more likely, serial output is slow).
> > And sgabios is useful for debugging.
>
> Ah, I see. debuglevel=1 prints too much and debuglevel=0 has no logging
> at all. We'd need seabios log at least the version banner to serial
> even with debuglevel=0 to replace sgabios.
>
> https://www.kraxel.org/cgit/qemu/log/?h=work/stripped-seabios
>
> Not hooked into -kernel yet, so you have to use "-bios bios-kboot.bin".
>
> Comments?
I think we were working on the same thing ... Attached is my
version.
Note that you must enable at least CONFIG_MPTABLE else virtio-scsi
does not work in the guest. I also enabled ACPI & SMBIOS & PIRTABLE.
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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>From 2c9b45d9d03c05573e1dbfc35e6750b127896be6 Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjo...@redhat.com>
Date: Fri, 1 Apr 2016 11:35:09 +0100
Subject: [PATCH] bios: Add fast variant of SeaBIOS for use with -kernel on
x86.
This commit adds a fast variant of SeaBIOS called 'bios-fast.bin'.
It's designed to be the fastest (also the smallest, but that's not the
main aim) SeaBIOS that is just enough to boot a Linux kernel using the
-kernel option on i686 and x86_64.
This commit does not modify the -kernel option to use this. You have
to specify it by doing something like this:
-kernel vmlinuz -bios bios-fast.bin
Signed-off-by: Richard W.M. Jones <rjo...@redhat.com>
---
Makefile | 3 ++-
roms/Makefile | 4 +++-
roms/config.seabios-fast | 12 ++++++++++++
3 files changed, 17 insertions(+), 2 deletions(-)
create mode 100644 roms/config.seabios-fast
diff --git a/Makefile b/Makefile
index 1d076a9..c4e939d 100644
--- a/Makefile
+++ b/Makefile
@@ -389,7 +389,8 @@ common de-ch es fo fr-ca hu ja mk nl-be
pt sl tr \
bepo cz
ifdef INSTALL_BLOBS
-BLOBS=bios.bin bios-256k.bin sgabios.bin vgabios.bin vgabios-cirrus.bin \
+BLOBS=bios.bin bios-256k.bin bios-fast.bin \
+sgabios.bin vgabios.bin vgabios-cirrus.bin \
vgabios-stdvga.bin vgabios-vmware.bin vgabios-qxl.bin vgabios-virtio.bin \
acpi-dsdt.aml \
ppc_rom.bin openbios-sparc32 openbios-sparc64 openbios-ppc QEMU,tcx.bin
QEMU,cgthree.bin \
diff --git a/roms/Makefile b/roms/Makefile
index 7bd1252..26b0586 100644
--- a/roms/Makefile
+++ b/roms/Makefile
@@ -61,9 +61,11 @@ default:
@echo " slof -- update slof.bin"
@echo " u-boot.e500 -- update u-boot.e500"
-bios: build-seabios-config-seabios-128k build-seabios-config-seabios-256k
+bios: build-seabios-config-seabios-128k build-seabios-config-seabios-256k \
+ build-seabios-config-seabios-fast
cp seabios/builds/seabios-128k/bios.bin ../pc-bios/bios.bin
cp seabios/builds/seabios-256k/bios.bin ../pc-bios/bios-256k.bin
+ cp seabios/builds/seabios-fast/bios.bin ../pc-bios/bios-fast.bin
seavgabios: $(patsubst %,seavgabios-%,$(vgabios_variants))
diff --git a/roms/config.seabios-fast b/roms/config.seabios-fast
new file mode 100644
index 0000000..98a4c27
--- /dev/null
+++ b/roms/config.seabios-fast
@@ -0,0 +1,12 @@
+# The most fastest SeaBIOS that can boot Linux using -kernel.
+CONFIG_USB=n
+CONFIG_DRIVES=n
+CONFIG_KEYBOARD=n
+CONFIG_MOUSE=n
+CONFIG_WRITABLE_UPPERMEMORY=y
+CONFIG_TCGBIOS=n
+CONFIG_PIRTABLE=y
+CONFIG_MPTABLE=y
+CONFIG_SMBIOS=y
+CONFIG_ACPI=y
+CONFIG_DEBUG_LEVEL=0
--
2.7.4
