diff options
| author | Uwe Kleine-König <u.kleine-koenig@pengutronix.de> | 2010-03-18 09:07:08 -0500 |
|---|---|---|
| committer | Alejandro Gonzalez <alex.gonzalez@digi.com> | 2011-01-17 14:55:16 +0100 |
| commit | 244f339205b4b0a4a5ceffe60bfcd3aded269129 (patch) | |
| tree | 59634974db9368e15522778a0d139180305cfea6 /Documentation | |
| parent | cb4597cef13c6e1425c7f05422c6fc71c17bf039 (diff) | |
Allow PHYS_OFFSET to be runtime determined
This bases on work done earlier by Lennert Buytenhek and Mark A. Greer.
Compared to their approach zreladdr isn't guessed based on the pc
register but the bootloader is expected to pass PHYS_OFFSET in r3. If
that value doesn't look right (e.g. isn't aligned) it is guessed based
on the value of sp. This should work for CONFIG_ZBOOT_ROM, too.
To use it for your machine removing the definition of PHYS_OFFSET from
<mach/memory.h> and selecting CONFIG_RUNTIME_PHYS_OFFSET should be
enough.
Cc: Lennert Buytenhek <buytenh@wantstofly.org>
Cc: Steve Chen <schen@mvista.com>
Cc: Mark A. Greer <mgreer@mvista.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/arm/Booting | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/Documentation/arm/Booting b/Documentation/arm/Booting index 76850295af8f..ec228a472bec 100644 --- a/Documentation/arm/Booting +++ b/Documentation/arm/Booting @@ -126,6 +126,7 @@ In either case, the following conditions must be met: r0 = 0, r1 = machine type number discovered in (3) above. r2 = physical address of tagged list in system RAM. + r3 = PHYS_OFFSET - CPU mode All forms of interrupts must be disabled (IRQs and FIQs) |