[PATCH 02/11] omap2/3: Fix DEBUG_LL for omap zoom2/3
Kevin Hilman
khilman at deeprootsystems.com
Fri Apr 30 17:20:42 EDT 2010
Tony Lindgren <tony at atomide.com> writes:
> * Kevin Hilman <khilman at deeprootsystems.com> [100430 13:50]:
>> Tony Lindgren <tony at 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 at ti.com>
>> > Cc: Vikram Pandita <vikram.pandita at ti.com>
>> > Signed-off-by: Tony Lindgren <tony at 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.
Hmm, then shouldn't that be fixed? I understood the .phys_io and and
.io_pg_offset fields of the mach_desc to be specifically for mapping
the early UART, and nothing else.
Kevin
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