Re: [PATCH 02/11] omap2/3: Fix DEBUG_LL for omap zoom2/3

[Tony Lindgren <tony@atomide.com>]

* Kevin Hilman <khilman@deeprootsystems.com> [100430 13:50]:
> Tony Lindgren <tony@atomide.com> writes:
> 
> > Zoom2 and 3 have UARTs only on the external debug board.
> > GPMC needs to be mapped early to use it for DEBUG_LL.
> >
> > Additionally, 0xfb000000 overlaps with other areas, so
> > use 0xfa400000 for the virtual address instead.
> >
> > Note that with the pending serial.c patches you need to
> > set console=ttyS0,115200n8 as it will be the only UART
> > mapped. To use DEBUG_LL, you need to pass also earlyprintk
> > in cmdline.
> >
> > Cc: Allen Pais <allen.pais@ti.com>
> > Cc: Vikram Pandita <vikram.pandita@ti.com>
> > Signed-off-by: Tony Lindgren <tony@atomide.com>
> > ---
> >  arch/arm/kernel/head.S                         |   10 ++++++++++
> >  arch/arm/mach-omap2/board-zoom-debugboard.c    |    2 +-
> >  arch/arm/mach-omap2/include/mach/debug-macro.S |    4 ++--
> >  arch/arm/mach-omap2/io.c                       |    9 +++++++++
> >  arch/arm/plat-omap/include/plat/serial.h       |    2 +-
> >  5 files changed, 23 insertions(+), 4 deletions(-)
> >
> > diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
> > index eb62bf9..fd870e1 100644
> > --- a/arch/arm/kernel/head.S
> > +++ b/arch/arm/kernel/head.S
> > @@ -328,6 +328,16 @@ __create_page_tables:
> >  	add	r0, r4, #0xd8000000 >> 18
> >  	str	r3, [r0]
> >  #endif
> > +#if defined(CONFIG_MACH_OMAP_ZOOM2) || defined(CONFIG_MACH_OMAP_ZOOM3)
> > +	/*
> > +	 * Zoom2 and Zoom3 have UARTs only on the debug board.
> > +	 * The debug board is connected to the GPMC.
> > +	 */
> > +	add	r0, r4, #0xfa000000 >> 18
> > +	orr	r0, r0, #0x00400000 >> 18	@ ZOOM_UART_VIRT
> > +	orr	r3, r7, #0x10000000		@ ZOOM_UART_BASE
> > +	str	r3, [r0]
> > +#endif
> 
> I don't see why this part is needed.  The same mapping is done using
> the .io_pg_offset in the machine description which is done just before
> this in head.S

That mapping does not cover the GPMC area where this UART is.

Tony