This patch adds support for low level debugging on TI816X boards. Currently the
support for UART3 console on TI816X EVM is added.
Signed-off-by: Hemant Pedanekar <hemantp@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Rather than checking the MMU status in every instance of addruart, do it
once in kernel/debug.S, and change the existing addruart macros to
return both physical and virtual addresses. The main debug code can then
select the appropriate address to use.
This will also allow us to retreive the address of a uart for the MMU
state that we're not current in.
Updated with fixes for OMAP from Jason Wang <jason77.wang@gmail.com>
and Tony Lindgren <tony@atomide.com>, and fix for versatile express from
Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>.
Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Jason Wang <jason77.wang@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Tested-by: Kevin Hilman <khilman@deeprootsystems.com>
Now we use a memory address to store the debug port info, So we need
to read/write this address when we choose DEBUG_LL. When MMU isn't
enable(I.E. the begining part of init stage of the linux kernel boot),
we need to access physical address instead of virtual address,
otherwise the kernel will crash.
Signed-off-by: Jason Wang <jason77.wang@gmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
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>
Acked-by: Vikram Pandita <vikram.pandita@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
This removes the dependency to the UART1 being available for storing
the debug configuration in uncompress.h. This will simplify the
DEBUG_LL UART configuration for boards that may not have UART1, or
have an external UART as it requires only one mapping for DEBUG_LL.
The patch has a few limitations. Basically now we're assuming that
the kernel uncompress code won't overlap with OMAP_UART_INFO. We also
assume the printascii is called at least once before paging_init in
order for addruart to have a chance to read the UART setup from
OMAP_UART_INFO.
As suggested by Cyril Chemparathy <cyril@ti.com>,
Vikram Pandita <vikram.pandita@ti.com> and
Kevin Hilman <khilman@deeprootsystems.com>. Based on an earlier
patch posted for Davinci by Cyril Chemparathy <cyril@ti.com>.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Define arch_decomp_setup() the same way as some other
architectures do. Use arch_id to configure the debug uart
based on the machine_is by storing it into the uart
scratchpad register for DEBUG_LL code to use.
Signed-off-by: Tony Lindgren <tony@atomide.com>
This way we don't have conflicts with the defines
with compiling in multiple omaps. Set the addresses
for uarts in struct omap_globals for the early serial
init code.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Otherwise more complicated uart configuration won't be possible.
We can use r1 for tmp register for both head.S and debug.S.
NOTE: This patch depends on another patch to add the the tmp register
into all debug-macro.S files. That can be done with:
$ sed -i -e "s/addruart,rx|addruart, rx/addruart, rx, tmp/"
arch/arm/*/include/*/debug-macro.S
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
