For SCC initialization we cannot assume that the control register is in
the correct state to accept a register pointer. So first read from the
control register in order to "sync" up.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Also fix a few printf-style formats, to get rid of the following compiler
warnings when DEBUG is enabled:
arch/m68k/kernel/traps.c: In function ‘access_error060’:
arch/m68k/kernel/traps.c:166: warning: format ‘%d’ expects type ‘int’, but argument 2 has type ‘long unsigned int’
arch/m68k/kernel/traps.c: In function ‘bus_error030’:
arch/m68k/kernel/traps.c:568: warning: format ‘%#lx’ expects type ‘long unsigned int’, but argument 2 has type ‘void *’
arch/m68k/kernel/traps.c:682: warning: format ‘%#lx’ expects type ‘long unsigned int’, but argument 2 has type ‘void *’
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Add optional support to export the bootinfo used to boot the kernel in a
"bootinfo" file in procfs. This is useful with kexec.
This is based on the similar feature for ATAGS on ARM.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
On m68k, get_cycles() (the default implementation for random_get_entropy())
always returns zero, providing no entropy for the random driver.
Add a hook where platforms can provide their own implementation, and wire
it up in the infrastructure provided by commit
61875f30da ("random: allow architectures to
optionally define random_get_entropy()").
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
nf_init() uses virt_to_phys(), which depends on m68k_memoffset being set and
module_fixup() having been called, but this is only done in paging_init().
Hence call paging_init() before nf_init().
This went unnoticed, as virt_to_phys() is a no-op on Atari, unless you start
fiddling with the memory blocks in the bootinfo manually.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Move generic definitions used by bootstraps to uapi/asm/bootinfo.h:
- Machine types,
- CPU, FPU, and MMU types,
- struct mem_info.
Keep a copy of struct mem_info for in-kernel use, and rename it to struct
m68k_mem_info, as the exported one will be modified later.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Export the bootinfo definitions that are used by bootstrap loaders, and
split them up in generic and platform-specific parts.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
struct mac_booter_data is no longer part of the bootinfo API, hence move it
from <asm/bootinfo.h> to <asm/macintosh.h>, dropping all unused fields in
the process.
Also remove the no longer used mac_booter_data pointer from head.S.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Since the introduction of init sections (which are located after BSS), the
bootinfo is no longer located right after the BSS, but after all kernel
sections.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
The low level interrupt entry code of m68k contains the following:
add_preempt_count(HARDIRQ_OFFSET);
do_IRQ();
irq_enter();
add_preempt_count(HARDIRQ_OFFSET);
handle_interrupt();
irq_exit();
sub_preempt_count(HARDIRQ_OFFSET);
if (in_interrupt())
return; <---- On m68k always taken!
if (local_softirq_pending())
do_softirq();
sub_preempt_count(HARDIRQ_OFFSET);
if (in_hardirq())
return;
if (status_on_stack_has_interrupt_priority_mask > 0)
return;
if (local_softirq_pending())
do_softirq();
ret_from_exception:
if (interrupted_context_is_kernel)
return:
....
I tried to find a proper explanation for this, but the changelog is
sparse and there are no mails explaining it further. But obviously
this relates to the interrupt priority levels of the m68k and tries to
be extra clever with nested interrupts. Though this cleverness just
adds code bloat to the interrupt hotpath.
For the common case of non nested interrupts the code runs through two
extra conditionals to the only important one, which checks whether the
return is to kernel or user space.
For the nested case the checks for in_hardirq() and the priority mask
value on stack catch only the case where the nested interrupt happens
inside the hard irq context of the first interrupt. If the nested
interrupt happens while the first interrupt handles soft interrupts,
then these extra checks buy nothing. The nested interrupt will fall
through to the final kernel/user space return check at
ret_from_exception.
Changing the code flow in the following way:
do_IRQ();
irq_enter();
add_preempt_count(HARDIRQ_OFFSET);
handle_interrupt();
irq_exit();
sub_preempt_count(HARDIRQ_OFFSET);
if (in_interrupt())
return;
if (local_softirq_pending())
do_softirq();
ret_from_exception:
if (interrupted_context_is_kernel)
return:
makes the region protected by the hardirq count slightly smaller and
the softirq handling is invoked with a minimal deeper stack. But
otherwise it's completely functional equivalent and saves 104 bytes of
text in arch/m68k/kernel/entry.o.
This modification allows us further to get rid of the limitations
which m68k puts on the preempt_count layout, so we can make the
preempt count bits completely generic.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Schmitz <schmitz@biophys.uni-duesseldorf.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Linux/m68k <linux-m68k@vger.kernel.org>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1311112052360.30673@ionos.tec.linutronix.de
Pull m68knommu fixes from Greg Ungerer:
"Just a small collection of cleanups and fixes this time, no big
changes. The most interresting are to make the m68k and m68knommu
consistently use CONFIG_IOMAP, clean out some unused board config
options and flush the cache on signal stack creation"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
m68k: remove 16 unused boards in Kconfig.machine
m68k: define 'VM_DATA_DEFAULT_FLAGS' no matter whether has 'NOMMU' or not
m68knommu: user generic iomap to support ioread*/iowrite*
m68k/coldfire: flush cache when creating the signal stack frame
m68knommu: Mark functions only called from setup_arch() __init
When the signal stack frame is created, it must be flushed in order to
make sure the cache fetches the correct data.
Without cache flush the icache might pick up old cached data from an older
signal stack frame if the signal is raised again very fast.
In case of copyback the data cache muist be pushed first, but is untested.
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Some functions that are only called (indirectly) from setup_arch() lack
__init annotations.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Pull "exotic" arch fixes from Geert Uytterhoeven:
"This is a collection of several exotic architecture fixes, and a few
other fixes for issues that were detected while doing the former"
* 'exotic-arch-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: (35 commits)
lib: Move fonts from drivers/video/console/ to lib/fonts/
console/font: Refactor font support code selection logic
Revert "staging/solo6x10: depend on CONFIG_FONTS"
input: cros_ec_keyb_clear_keyboard() depends on CONFIG_PM_SLEEP
score: Wire up asm-generic/xor.h
score: Remove unneeded <asm/dma-mapping.h>
openrisc: Wire up asm-generic/xor.h
h8300/boot: Use POSIX "$((..))" instead of bashism "$[...]"
h8300: Mark H83002 and H83048 CPU support broken
h8300: Switch h8300 to drivers/Kconfig
h8300: Limit timer channel ranges in Kconfig
h8300: Wire up asm-generic/xor.h
h8300: Fill the system call table using a CALL() macro
h8300: Fix <asm/tlb.h>
h8300: Hardcode symbol prefixes in asm sources
h8300: add missing definition for read_barries_depends()
frv: head.S - Remove commented-out initialization code
cris: Wire up asm-generic/vga.h
parport: disable PC-style parallel port support on cris
console: Disable VGA text console support on cris
...
Several drivers need font support independent of CONFIG_VT, cfr. commit
9cbce8d7e1dae0744ca4f68d62aa7de18196b6f4, "console/font: Refactor font
support code selection logic").
Hence move the fonts and their support logic from drivers/video/console/ to
its own library directory lib/fonts/.
This also allows to limit processing of drivers/video/console/Makefile to
CONFIG_VT=y again.
[Kevin Hilman <khilman@linaro.org>: Update arch/arm/boot/compressed/Makefile]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
To get vectored interrupts working we need to switch from the default
handler handle_bad_irq() to something more sensible. Tested on a MVME177
board.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
The present code does not wait for the SCC to finish resetting itself
before trying to initialise the device. The result is that the SCC
interrupt sources become enabled (if they weren't already). This leads to
an early boot crash (unexpected interrupt) given CONFIG_EARLY_PRINTK. Fix
this by adding a delay. A successful reset disables the interrupt sources.
Also, after the reset for channel A setup, the SCC then gets a second
reset for channel B setup which leaves channel A uninitialised again. Fix
this by performing the reset only once.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Cc: stable@vger.kernel.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Both dump_stack() and show_stack() are currently implemented by each
architecture. show_stack(NULL, NULL) dumps the backtrace for the
current task as does dump_stack(). On some archs, dump_stack() prints
extra information - pid, utsname and so on - in addition to the
backtrace while the two are identical on other archs.
The usages in arch-independent code of the two functions indicate
show_stack(NULL, NULL) should print out bare backtrace while
dump_stack() is used for debugging purposes when something went wrong,
so it does make sense to print additional information on the task which
triggered dump_stack().
There's no reason to require archs to implement two separate but mostly
identical functions. It leads to unnecessary subtle information.
This patch expands the dummy fallback dump_stack() implementation in
lib/dump_stack.c such that it prints out debug information (taken from
x86) and invokes show_stack(NULL, NULL) and drops arch-specific
dump_stack() implementations in all archs except blackfin. Blackfin's
dump_stack() does something wonky that I don't understand.
Debug information can be printed separately by calling
dump_stack_print_info() so that arch-specific dump_stack()
implementation can still emit the same debug information. This is used
in blackfin.
This patch brings the following behavior changes.
* On some archs, an extra level in backtrace for show_stack() could be
printed. This is because the top frame was determined in
dump_stack() on those archs while generic dump_stack() can't do that
reliably. It can be compensated by inlining dump_stack() but not
sure whether that'd be necessary.
* Most archs didn't use to print debug info on dump_stack(). They do
now.
An example WARN dump follows.
WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
Hardware name: empty
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #9
0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
ffffffff8108f50f ffffffff82228240 0000000000000040 ffffffff8234a03c
0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
Call Trace:
[<ffffffff81c614dc>] dump_stack+0x19/0x1b
[<ffffffff8108f50f>] warn_slowpath_common+0x7f/0xc0
[<ffffffff8108f56a>] warn_slowpath_null+0x1a/0x20
[<ffffffff8234a071>] init_workqueues+0x35/0x505
...
v2: CPU number added to the generic debug info as requested by s390
folks and dropped the s390 specific dump_stack(). This loses %ksp
from the debug message which the maintainers think isn't important
enough to keep the s390-specific dump_stack() implementation.
dump_stack_print_info() is moved to kernel/printk.c from
lib/dump_stack.c. Because linkage is per objecct file,
dump_stack_print_info() living in the same lib file as generic
dump_stack() means that archs which implement custom dump_stack()
- at this point, only blackfin - can't use dump_stack_print_info()
as that will bring in the generic version of dump_stack() too. v1
The v1 patch broke build on blackfin due to this issue. The build
breakage was reported by Fengguang Wu.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [s390 bits]
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon bits]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
