On 02/22/2014 01:20 AM, Dennis Gilmore wrote:
On Wed, 19 Feb 2014 10:40:15 -0700 Stephen Warren swarren@wwwdotorg.org wrote:
On 02/17/2014 10:56 AM, Dennis Gilmore wrote:
diff --git a/include/config_distro_bootcmd.h
+#define BOOTCMDS_COMMON \
- "rootpart=1\0" \
We should really stop hard-coding that. I meant to (but evidently never got around to) re-write the commands so that they could automatically determine which partition to use, based on the MBR bootable flag or GPT partition flags.
Still, we can probably make that enhancement separately later.
I fully agree, we should be able to work it out later. I also renamed it to bootpart since it is where we will boot from, which may or may not be the root filesystem
Just as some history, when I first wrote these boot scripts for Tegra, I was actually using that variable both inside the environment scripts to find/load boot.scr, and within boot.scr to set the kernel root= command-line option. More recently, I've moved to using root=PARTUUID= or root=UUID= on the kernel command-line, so rootpart has become less relevant, and indeed renaming it bootpart does make a lot more sense, as you say.
- "scan_boot="
\
"echo Scanning ${devtype} ${devnum}...;" \
"for prefix in ${boot_prefixes}; do" \
"run sysboot_boot;" \
"run envimport;" \
"run script_boot;" \
This isn't quite right for the Raspberry Pi at least.
What I wanted was for uEnv.txt to *always* be loaded from SD card before any other boot activity. The SD card is known to exist on this platform, since it's the only place the SoC's boot ROM can load the initial binary firmware from.
I know some distros use commands in uEnv.txt to boot, or at the least they set variables and load a boot.scr I was trying to make sure we cover those people. The definition of what uEnv.txt is and how it should be used is pretty murky to me. I have seen it used in a few different ways. I know some people really want them. So probably best to work out a better way to support it. http://eewiki.net/display/linuxonarm/BeagleBone+Black#BeagleBoneBlack-uEnv.t... for instance specifies all the boot commands in uEnv.txt really I would rather people just use a extlinux.conf file, I just do not want to take away the option to use something people see as valuable.
I'd suggest not touching uEnv.txt in config_distro_bootcmd.h, since it's really not a part of the new standard we want to create. Instead, have each board define CONFIG_PREBOOT to load it if they want it. I assume that a very small number of boards will need uEnv.txt once we've switched to this new scheme; just those that have nowhere to store a persistent environment.