Remove the circular buffering mechanism for exceptions. Instead, point RETX
at a safe location from which to fetch three NOPs.
This safe location is now in the fixed code area, and also used for certain
anomaly workarounds, to ensure that user space can find a valid ICPLB when
things are built with CONFIG_MPU.
Also, save I/DCPLB_FAULT_ADDRESS when lowering to level 5, since the hardware
reg is valid only at exception level.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
- add platform device resources in board files
- add new bfin_sir.h to each machines
Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
The irq setup code no longer calls gpio request and free.
This patch also changes the default gpio_free behavior on Blackfin.
A freed GPIO keeps it's last state, and is not defaulted back to
an input. This is also what all other architectures do.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
detect the memory available in the system on the fly by default
rather than forcing people to set this manually in the kconfig
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=3978
Section data_l1_cacheline_aligned should be defined in
link script of kernel, when L1 data sram bank A is not available.
In bf536 with all data cache is enabled, there is no L1 data sram.
Current link script won't define section data_l1.cacheline_aligned in
this case. But, if user select put cacheline_aligned data into l1 sram
in kernel menuconfig, these data will be dropped and access to these
data will trigger data CPLB exception.
Do panic in l1 relocation code as well.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
- allow bootrom to be readable from supervisor mode
- delete unused local variable "addr"
- punt unused local defines of cplbinfo.c
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
The DMA base registers are available in a global named "base_addr" for
every Blackfin variant. Give this a more descriptive name, and remove
duplicate tables from some drivers.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
theres no need to declare ram{end,start,base} in the head.S files
when declaring them with the other memory related variables in setup.c
is so much simpler/nicer
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
remove duplicated prototypes for internal cplb structures from
the global blackfin header as nothing else should be accessing these
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Previously, init failed to do anything meaningful;
it turns out that the reason is that FD-PIC has a readonly data
section which can be located in the XIP filesystem, and various address checks
in the kernel reject such addresses for syscall arguments. Hence, init's
execve ("/bin/sh", ...)
failed with error code EFAULT.
There's room for improvement here: in case people want to have filesystems
on flash rather than in main memory, _access_ok should be modified to
allow this.
This bug fix is also dedicated to Michael Hennerich.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
The function flush_switched_dcplbs was clearing the CPLB entries covering
the process permission bitmasks. This means that the sequence
flush_switched_dcplbs ();
set_mask_dcplbs(mm->context.page_rwx_mask);
has a problem: if kernel code (such as an interrupt) causes a CPLB miss before
set_mask_dcplbs completes, the CPLB handler function causes a double fault,
with an instantaneous reboot.
This bug fix is dedicated to Michael Hennerich, the only person in the world
capable of providing working JTAG hardware.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
This is a rather old performance improvement for the signal handling
code, which was originally only committed on the 2007R1 branch as a
workaround for what we suspected to be a hardware bug.
There's no point in constructing a sigreturn stub on the stack and
flushing caches; we can just make signal handlers return to a known
location in the fixed code area.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
relocate MAX_SWITCH_{D,I}_CPLBS from the header to the file
where it actually gets used. this way when we change
CONFIG_MEM_SIZE in our kconfig, we only rebuild one or two files
rather than a whole bunch that implicitly include cplb.h.
this will also remove the ability to clear the swapcount on
the fly, but i really dont think that functionality is important.
ultimate goal is for CONFIG_MEM_SIZE to go away and calculate
this value on the fly based on what u-boot programmed for us.
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
There were a couple of problems with the way the trace buffer state
is saved/restored in assembly. The DEBUG_HWTRACE_SAVE/RESTORE macros
save a value to the stack, which is not immediately obvious; the CPLB
exception code needed changes to load the correct value of the stack
pointer. The other problem is that the SAVE/RESTORE macros weren't
pushing and popping the value downwards on the stack, but rather moving
it _upwards_, which is of course completely broken.
We also need to make sure there's a matching DEBUG_HWTRACE_RESTORE in
the error case of the CPLB handler.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
grab locks when not atomic - this fixes the issues
sometimes seen when using magic sysrq.
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Sometimes when we crash, current is not valid, (has been written
over), so the existing code causes a invalid read during exception
context - which is a unrecoverable double fault. This fixes this.
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
