linux-toradex.git/arch/powerpc/kernel/head_40x.S, branch v4.2.7

powerpc: Remove check for CONFIG_SERIAL_TEXT_DEBUG

2014-06-11T06:31:21+00:00

The Kconfig symbol SERIAL_TEXT_DEBUG was removed from
arch/powerpc/Kconfig.debug in v2.6.22. (In v2.6.27 it was also removed
from arch/ppc/Kconfig.debug.) So the check for its macro has evaluated
to false for over five years now. Remove that check and the few lines
of code hidden behind it.

Signed-off-by: Paul Bolle 
Signed-off-by: Benjamin Herrenschmidt

powerpc: Remove the empty giveup_fpu() function on 32bit kernel

2013-08-14T04:59:50+00:00

Instead of implementing an empty giveup_fpu() function for each
32bit processor type, replace them with an unique empty inline
function.

Signed-off-by: Kevin Hao 
Signed-off-by: Benjamin Herrenschmidt

powerpc: Enable the Watchdog vector for 405

2013-01-10T03:43:46+00:00

The watchdog and FIT code has been #if 0'd for ever, if the CPU takes
an exception to either of those vectors it will jump into the middle
of the PIT or Data TLB code and surely crash.

At least some (all?) 405 cores have both the WDT and FIT
vectors defined, so lets have proper entry points for them.

Tested that the WDT vector works on a 405F6 core.

Signed-off-by: Jason Gunthorpe 
Signed-off-by: Benjamin Herrenschmidt

powerpc: Call do_page_fault() with interrupts off

2012-03-08T23:55:08+00:00

We currently turn interrupts back to their previous state before
calling do_page_fault(). This can be annoying when debugging as
a bad fault will potentially have lost some processor state before
getting into the debugger.

We also end up calling some generic code with interrupts enabled
such as notify_page_fault() with interrupts enabled, which could
be unexpected.

This changes our code to behave more like other architectures,
and make the assembly entry code call into do_page_faults() with
interrupts disabled. They are conditionally re-enabled from
within do_page_fault() in the same spot x86 does it.

While there, add the might_sleep() test in the case of a successful
trylock of the mmap semaphore, again like x86.

Also fix a bug in the existing assembly where r12 (_MSR) could get
clobbered by C calls (the DTL accounting in the exception common
macro and DISABLE_INTS) in some cases.

Signed-off-by: Benjamin Herrenschmidt 
---

v2. Add the r12 clobber fix

powerpc/32: Pass device tree address as u64 to machine_init

2011-09-19T23:19:47+00:00

u64 is used rather than phys_addr_t to keep things simple, as
this is called from assembly code.

Update callers to pass a 64-bit address in r3/r4.  Other unused
register assignments that were once parameters to machine_init
are dropped.

For FSL BookE, look up the physical address of the device tree from the
effective address passed in r3 by the loader.  This is required for
situations where memory does not start at zero (due to AMP or IOMMU-less
virtualization), and thus the IMA doesn't start at zero, and thus the
device tree effective address does not equal the physical address.

Signed-off-by: Scott Wood 
Signed-off-by: Benjamin Herrenschmidt

Fix common misspellings

2011-03-31T14:26:23+00:00

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi

powerpc: Remove second definition of STACK_FRAME_OVERHEAD

2010-11-29T04:48:23+00:00

Since STACK_FRAME_OVERHEAD is defined in asm/ptrace.h and that
is ASSEMBER safe, we can just include that instead of going via
asm-offsets.h.

Signed-off-by: Stephen Rothwell 
Signed-off-by: Benjamin Herrenschmidt

memblock: Remove rmo_size, burry it in arch/powerpc where it belongs

2010-08-05T02:56:08+00:00

The RMA (RMO is a misnomer) is a concept specific to ppc64 (in fact
server ppc64 though I hijack it on embedded ppc64 for similar purposes)
and represents the area of memory that can be accessed in real mode
(aka with MMU off), or on embedded, from the exception vectors (which
is bolted in the TLB) which pretty much boils down to the same thing.

We take that out of the generic MEMBLOCK data structure and move it into
arch/powerpc where it belongs, renaming it to "RMA" while at it.

Signed-off-by: Benjamin Herrenschmidt

powerpc: Use names rather than numbers for SPRGs (v2)

2009-08-20T00:12:27+00:00

The kernel uses SPRG registers for various purposes, typically in
low level assembly code as scratch registers or to hold per-cpu
global infos such as the PACA or the current thread_info pointer.

We want to be able to easily shuffle the usage of those registers
as some implementations have specific constraints realted to some
of them, for example, some have userspace readable aliases, etc..
and the current choice isn't always the best.

This patch should not change any code generation, and replaces the
usage of SPRN_SPRGn everywhere in the kernel with a named replacement
and adds documentation next to the definition of the names as to
what those are used for on each processor family.

The only parts that still use the original numbers are bits of KVM
or suspend/resume code that just blindly needs to save/restore all
the SPRGs.

Signed-off-by: Benjamin Herrenschmidt

powerpc: convert to use __HEAD and HEAD_TEXT macros.

2009-04-26T16:20:38+00:00

This has the consequence of changing the section name use for head
code from ".text.head" to ".head.text".  Since this commit changes all
users in the architecture, this change should be harmless.

Signed-off-by: Tim Abbott 
Cc: Benjamin Herrenschmidt 
Acked-by: Sam Ravnborg 
Signed-off-by: Linus Torvalds