[U-Boot] [PATCH 25/26] x86: doc: Minor update for accuracy

Bin Meng
2016-05-02T07:33:45Z

This updates the doc for the following places:
- Mention CRB for Bayley Bay
- Limit part of the QEMU paragraphs to 80 cols
- Correct some typos (drive, it's, Ubuntu)
- Add description for "console=ttyS0,115200"
- Remove CONFIG_BOOTDELAY description which is already
in x86-common.h

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
---

doc/README.x86 | 40 +++++++++++++++++-----------------------
1 file changed, 17 insertions(+), 23 deletions(-)

diff --git a/doc/README.x86 b/doc/README.x86
index c5c3010..a5dfb86 100644
--- a/doc/README.x86
+++ b/doc/README.x86
@@ -23,7 +23,7 @@ In this case, known as bare mode, from the fact that it runs on the
'bare metal', U-Boot acts like a BIOS replacement. The following platforms
are supported:

- - Bayley Bay
+ - Bayley Bay CRB
- Cougar Canyon 2 CRB
- Crown Bay CRB
- Galileo
@@ -412,18 +412,19 @@ If you want to check both consoles, use '-serial stdio'.
Multicore is also supported by QEMU via '-smp n' where n is the number of cores
to instantiate. Note, the maximum supported CPU number in QEMU is 255.

-The fw_cfg interface in QEMU also provides information about kernel data, initrd,
-command-line arguments and more. U-Boot supports directly accessing these informtion
-from fw_cfg interface, this saves the time of loading them from hard disk or
-network again, through emulated devices. To use it , simply providing them in
-QEMU command line:
+The fw_cfg interface in QEMU also provides information about kernel data,
+initrd, command-line arguments and more. U-Boot supports directly accessing
+these informtion from fw_cfg interface, which saves the time of loading them
+from hard disk or network again, through emulated devices. To use it , simply
+providing them in QEMU command line:

$ qemu-system-i386 -nographic -bios path/to/u-boot.rom -m 1024 -kernel /path/to/bzImage
-append 'root=/dev/ram console=ttyS0' -initrd /path/to/initrd -smp 8

Note: -initrd and -smp are both optional

-Then start QEMU, in U-Boot command line use the following U-Boot command to setup kernel:
+Then start QEMU, in U-Boot command line use the following U-Boot command to
+setup kernel:

=> qfw
qfw - QEMU firmware interface
@@ -437,8 +438,8 @@ qfw <command>
=> qfw load
loading kernel to address 01000000 size 5d9d30 initrd 04000000 size 1b1ab50

-Here the kernel (bzImage) is loaded to 01000000 and initrd is to 04000000. Then, 'zboot'
-can be used to boot the kernel:
+Here the kernel (bzImage) is loaded to 01000000 and initrd is to 04000000. Then,
+'zboot' can be used to boot the kernel:

=> zboot 02000000 - 04000000 1b1ab50

@@ -490,8 +491,8 @@ Booting Ubuntu
--------------
As an example of how to set up your boot flow with U-Boot, here are
instructions for starting Ubuntu from U-Boot. These instructions have been
-tested on Minnowboard MAX with a SATA driver but are equally applicable on
-other platforms and other media. There are really only four steps and its a
+tested on Minnowboard MAX with a SATA drive but are equally applicable on
+other platforms and other media. There are really only four steps and it's a
very simple script, but a more detailed explanation is provided here for
completeness.

@@ -499,7 +500,7 @@ Note: It is possible to set up U-Boot to boot automatically using syslinux.
It could also use the grub.cfg file (/efi/ubuntu/grub.cfg) to obtain the
GUID. If you figure these out, please post patches to this README.

-Firstly, you will need Ubunutu installed on an available disk. It should be
+Firstly, you will need Ubuntu installed on an available disk. It should be
possible to make U-Boot start a USB start-up disk but for now let's assume
that you used another boot loader to install Ubuntu.

@@ -659,7 +660,7 @@ U-Boot:
Loading bzImage at address 100000 (5805728 bytes)
Magic signature found
Initial RAM disk at linear address 0x04000000, size 19215259 bytes
- Kernel command line: "console=ttyS0,115200 root=/dev/disk/by-partuuid/965c59ee-1822-4326-90d2-b02446050059 ro"
+ Kernel command line: "root=/dev/disk/by-partuuid/965c59ee-1822-4326-90d2-b02446050059 ro"

Starting kernel ...

@@ -679,13 +680,14 @@ above commands into a script since then it will be faster.
240,329 ahci
1,422,704 vesa display

-Now the kernel actually starts:
+Now the kernel actually starts: (if you want to examine kernel boot up message
+on the serial console, append "console=ttyS0,115200" to the kernel command line)

[ 0.000000] Initializing cgroup subsys cpuset
[ 0.000000] Initializing cgroup subsys cpu
[ 0.000000] Initializing cgroup subsys cpuacct
[ 0.000000] Linux version 3.13.0-58-generic (buildd at allspice) (gcc version 4.8.2 (Ubuntu 4.8.2-19ubuntu1) ) #97-Ubuntu SMP Wed Jul 8 02:56:15 UTC 2015 (Ubuntu 3.13.0-58.97-generic 3.13.11-ckt22)
- [ 0.000000] Command line: console=ttyS0,115200 root=/dev/disk/by-partuuid/965c59ee-1822-4326-90d2-b02446050059 ro
+ [ 0.000000] Command line: root=/dev/disk/by-partuuid/965c59ee-1822-4326-90d2-b02446050059 ro console=ttyS0,115200

It continues for a long time. Along the way you will see it pick up your
ramdisk:
@@ -736,14 +738,6 @@ If you want to put this in a script you can use something like this:
The \ is to tell the shell not to evaluate ${filesize} as part of the setenv
command.

-You will also need to add this to your board configuration file, e.g.
-include/configs/minnowmax.h:
-
- #define CONFIG_BOOTDELAY 2
-
-Now when you reset your board it wait a few seconds (in case you want to
-interrupt) and then should boot straight into Ubuntu.
-
You can also bake this behaviour into your build by hard-coding the
environment variables if you add this to minnowmax.h:

--
1.8.2.1