[PATCH 0/3] Allow late mdesc detection, v4

Kevin Hilman khilman at deeprootsystems.com
Fri Aug 27 14:21:05 EDT 2010


Jeremy Kerr <jeremy.kerr at canonical.com> writes:

> Currently, we probe for a mdesc early in boot. At this early stage, the
> only thing we use the mdesc for is to determine the debug page mapping.
>
> However, the debug addresses (phys and virt) need to be coded into the
> addruart macro anyway; the dynamic probing is only going to tell us what
> we already know.
>
> These changes allow us to use the addruart macros to find the debug
> mapping addresses, rather than pulling them out of the mdesc. This means
> that the addresses are only kept in the one place, and that we don't
> need the mdesc nearly as early.
>
> The first change updates all of the addruart macros to return both
> physical and virtual addresses. I've used 'rp' and 'rv' as the macro
> arguments to indicate which address goes where
>
> The second change updates the debug setup routine to use the addruart
> macro to establish the debug mapping, now that we can invoke the macro
> to find the phyical and virtual addresses.
>
> This allows us to delay the requirement to have a mdesc available until
> much later. For example, we can parse one from the device tree once
> we've reached C code.
>
> As they have more complex and/or new debug macros, the following platforms
> could do with extra testing:
>  * omap (mach-omap1 and mach-omap2)
>  * davinci

Tested on a couple flavors of DaVinci SoCs, so for davinci

Signed-off-by: Kevin Hilman <khilman at deeprootsystems.com>


>  * tegra
>
> Cheers,
>
>
> Jeremy
>
> v4:
>  * updates for 2.6.36
>  * add changes for tegra
>  * update davinci
>  * include fixes for omap[12]
>  * drop mdesc changes
>
> v3:
>  * only establish page mapping if !DEBUG_ICEDCC
>
> v2:
>  * return both phys and virt addresses from addruart
>  * mask unneeded bits from uart physical address in mapping setup
>  * remove io_pg_offst and phys_io, in a separate patch
>
> ---
> Jeremy Kerr (3):
>       arm/debug: consolidate addruart macros for CONFIG_DEBUG_ICEDCC
>       arm: return both physical and virtual addresses from addruart
>       arm: use addruart macro to establish debug mappings
>
>
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