ioremap_base is not initialised and is nowhere used so remove it
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NScott Wood <oss@buserror.net>

x_mapped_by_bats() and x_mapped_by_tlbcam() serve the same kind of
purpose, and are never defined at the same time.
So rename them x_block_mapped() and define them in the relevant
places
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NScott Wood <oss@buserror.net>

On a live running system (VoIP gateway for Air Trafic Control), over
a 10 minutes period (with 277s idle), we get 87 millions DTLB misses
and approximatly 35 secondes are spent in DTLB handler.
This represents 5.8% of the overall time and even 10.8% of the
non-idle time.
Among those 87 millions DTLB misses, 15% are on user addresses and
85% are on kernel addresses. And within the kernel addresses, 93%
are on addresses from the linear address space and only 7% are on
addresses from the virtual address space.

MPC8xx has no BATs but it has 8Mb page size. This patch implements
mapping of kernel RAM using 8Mb pages, on the same model as what is
done on the 40x.

In 4k pages mode, each PGD entry maps a 4Mb area: we map every two
entries to the same 8Mb physical page. In each second entry, we add
4Mb to the page physical address to ease life of the FixupDAR
routine. This is just ignored by HW.

In 16k pages mode, each PGD entry maps a 64Mb area: each PGD entry
will point to the first page of the area. The DTLB handler adds
the 3 bits from EPN to map the correct page.

With this patch applied, we now get only 13 millions TLB misses
during the 10 minutes period. The idle time has increased to 313s
and the overall time spent in DTLB miss handler is 6.3s, which
represents 1% of the overall time and 2.2% of non-idle time.
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NScott Wood <oss@buserror.net>

This changes _PAGE_PRESENT for 64-bit Book 3S processors from 0x2 to
0x8000_0000_0000_0000, because that is where PowerISA v3.0 CPUs in
radix mode will expect to find it.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This is required for kdump to work when loaded at at an address that
does not fall within the first TLB entry -- which can easily happen
because while the lower limit is enforced via reserved memory, which
doesn't affect how much is mapped, the upper limit is enforced via a
different mechanism that does.  Thus, more TLB entries are needed than
would normally be used, as the total memory to be mapped might not be a
power of two.
Signed-off-by: NScott Wood <scottwood@freescale.com>

Use an AS=1 trampoline TLB entry to allow all normal TLB1 entries to
be loaded at once.  This avoids the need to keep the translation that
code is executing from in the same TLB entry in the final TLB
configuration as during early boot, which in turn is helpful for
relocatable kernels (e.g. kdump) where the kernel is not running from
what would be the first TLB entry.

On e6500, we limit map_mem_in_cams() to the primary hwthread of a
core (the boot cpu is always considered primary, as a kdump kernel
can be entered on any cpu).  Each TLB only needs to be set up once,
and when we do, we don't want another thread to be running when we
create a temporary trampoline TLB1 entry.
Signed-off-by: NScott Wood <scottwood@freescale.com>

The callers of setbat() are actually passing a pgprot_t for the flags
parameter. This doesn't matter unless STRICT_MM_TYPECHECKS is enabled.
So we can turn that on without breaking the build, change setbat() to
take a pgprot_t and have it convert it to an unsigned long internally.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

When booting above the 64M for a secondary cpu, we also face the
same issue as the boot cpu that the PAGE_OFFSET map two different
physical address for the init tlb and the final map. So we have to use
switch_to_as1/restore_to_as0 between the conversion of these two
maps. When restoring to as0 for a secondary cpu, we only need to
return to the caller. So add a new parameter for function
restore_to_as0 for this purpose.

Use LOAD_REG_ADDR_PIC to get the address of variables which may
be used before we set the final map in cams for the secondary cpu.
Move the setting of cams a bit earlier in order to avoid the
unnecessary using of LOAD_REG_ADDR_PIC.
Signed-off-by: NKevin Hao <haokexin@gmail.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

This is always true for a non-relocatable kernel. Otherwise the kernel
would get stuck. But for a relocatable kernel, it seems a little
complicated. When booting a relocatable kernel, we just align the
kernel start addr to 64M and map the PAGE_OFFSET from there. The
relocation will base on this virtual address. But if this address
is not the same as the memstart_addr, we will have to change the
map of PAGE_OFFSET to the real memstart_addr and do another relocation
again.
Signed-off-by: NKevin Hao <haokexin@gmail.com>
[scottwood@freescale.com: make offset long and non-negative in simple case]
Signed-off-by: NScott Wood <scottwood@freescale.com>

We use the tlb1 entries to map low mem to the kernel space. In the
current code, it assumes that the first tlb entry would cover the
kernel image. But this is not true for some special cases, such as
when we run a relocatable kernel above the 64M or set
CONFIG_KERNEL_START above 64M. So we choose to switch to address
space 1 before setting these tlb entries.
Signed-off-by: NKevin Hao <haokexin@gmail.com>
Signed-off-by: NScott Wood <scottwood@freescale.com>

On FSL Book-E devices we support multiple large TLB sizes and so we can
get into situations in which the initial 1G TLB size is too big and
we're asked for a size that is not mappable by a single entry (like
512M).  The single entry is important because when we bring up secondary
cores they need to ensure any data structure they need to access (eg
PACA or stack) is always mapped.

So we really need to determine what size will actually be mapped by the
first TLB entry to ensure we limit early memory references to that
region.  We refactor the map_mem_in_cams() code to provider a helper
function that we can utilize to determine the size of the first TLB
entry while taking into account size and alignment constraints.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

On Freescale parts typically have TLB array for large mappings that we can
bolt the linear mapping into.  We utilize the code that already exists
on PPC32 on the 64-bit side to setup the linear mapping to be cover by
bolted TLB entries.  We utilize a quarter of the variable size TLB array
for this purpose.

Additionally, we limit the amount of memory to what we can cover via
bolted entries so we don't get secondary faults in the TLB miss
handlers.  We should fix this limitation in the future.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

When we build with ftrace enabled its possible that loadcam_entry would
have used the stack pointer (even though the code doesn't need it).  We
call loadcam_entry in __secondary_start before the stack is setup.  To
ensure that loadcam_entry doesn't use the stack pointer the easiest
solution is to just have it in asm code.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

When we build with ftrace enabled its possible that loadcam_entry would
have used the stack pointer (even though the code doesn't need it).  We
call loadcam_entry in __secondary_start before the stack is setup.  To
ensure that loadcam_entry doesn't use the stack pointer the easiest
solution is to just have it in asm code.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

This patch adds the base support for the 476 processor.  The code was
primarily written by Ben Herrenschmidt and Torez Smith, but I've been
maintaining it for a while.

The goal is to have a single binary that will run on 44x and 47x, but
we still have some details to work out.  The biggest is that the L1 cache
line size differs on the two platforms, but it's currently a compile-time
option.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NTorez Smith  <lnxtorez@linux.vnet.ibm.com>
Signed-off-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>

Today's linux-next build (powerpc ppc44x_defconfig) failed like this:

arch/powerpc/mm/pgtable_32.c: In function 'mapin_ram':
arch/powerpc/mm/pgtable_32.c:318: error: too many arguments to function 'mmu_mapin_ram'

Casued by commit de32400d ("wii: use both
mem1 and mem2 as ram").
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Add a flag to let a platform ioremap memory regions marked as reserved.

This flag will be used later by the Nintendo Wii support code to allow
ioremapping the I/O region sitting between MEM1 and MEM2 and marked
as reserved RAM in the patch "wii: use both mem1 and mem2 as ram".

This will no longer be needed when proper discontig memory support
for 32-bit PowerPC is added to the kernel.
Signed-off-by: NAlbert Herranz <albert_herranz@yahoo.es>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

The Nintendo Wii video game console has two discontiguous RAM regions:
- MEM1: 24MB @ 0x00000000
- MEM2: 64MB @ 0x10000000

Unfortunately, the kernel currently does not support discontiguous RAM
memory regions on 32-bit PowerPC platforms.

This patch adds a series of workarounds to allow the use of the second
memory region (MEM2) as RAM by the kernel.
Basically, a single range of memory from the beginning of MEM1 to the
end of MEM2 is reported to the kernel, and a memory reservation is
created for the hole between MEM1 and MEM2.

With this patch the system is able to use all the available RAM and not
just ~27% of it.

This will no longer be needed when proper discontig memory support
for 32-bit PowerPC is added to the kernel.
Signed-off-by: NAlbert Herranz <albert_herranz@yahoo.es>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Re-write the code so its more standalone and fixed some issues:
* Bump'd # of CAM entries to 64 to support e500mc
* Make the code handle MAS7 properly
* Use pr_cont instead of creating a string as we go
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

The base TLB support didn't include support for SPARSEMEM_VMEMMAP, though
we did carve out some virtual space for it, the necessary support code
wasn't there. This implements it by using 16M pages for now, though the
page size could easily be changed at runtime if necessary.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This adds the TLB miss handler assembly, the low level TLB flush routines
along with the necessary hook for dealing with our virtual page tables
or indirect TLB entries that need to be flushes when PTE pages are freed.

There is currently no support for hugetlbfs
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

We need to pass down whether the page is direct or indirect and we'll
need to pass the page size to _tlbil_va and _tlbivax_bcast

We also add a new low level _tlbil_pid_noind() which does a TLB flush
by PID but avoids flushing indirect entries if possible

This implements those new prototypes but defines them with inlines
or macros so that no additional arguments are actually passed on current
processors.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This is a brown paper bag from one of my earlier patches that
breaks build on 40x and 8xx.

And yes, I've now added 40x and 8xx to my list of test configs :-)
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This is a global variable defined in fsl_booke_mmu.c with a value that gets
initialized in assembly code in head_fsl_booke.S.

It's never used.

If some code ever does want to know the number of entries in TLB1, then
"numcams = mfspr(SPRN_TLB1CFG) & 0xfff", is a whole lot simpler than a
global initialized during kernel boot from assembly.
Signed-off-by: NTrent Piepho <tpiepho@freescale.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

Some assembly code in head_fsl_booke.S hard-coded the size of struct tlbcam
to 20 when it indexed the TLBCAM table.  Anyone changing the size of struct
tlbcam would not know to expect that.

The kernel already has a system to get the size of C structures into
assembly language files, asm-offsets, so let's use it.

The definition of the struct gets moved to a header, so that asm-offsets.c
can include it.
Signed-off-by: NTrent Piepho <tpiepho@freescale.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

Currently, the various forms of low level TLB invalidations are all
implemented in misc_32.S for 32-bit processors, in a fairly scary
mess of #ifdef's and with interesting duplication such as a whole
bunch of code for FSL _tlbie and _tlbia which are no longer used.

This moves things around such that _tlbie is now defined in
hash_low_32.S and is only used by the 32-bit hash code, and all
nohash CPUs use the various _tlbil_* forms that are now moved to
a new file, tlb_nohash_low.S.

I moved all the definitions for that stuff out of
include/asm/tlbflush.h as they are really internal mm stuff, into
mm/mmu_decl.h

The code should have no functional changes.  I kept some variants
inline for trivial forms on things like 40x and 8xx.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The function flush_HPTE() is used in only one place, the implementation
of DEBUG_PAGEALLOC on ppc32.

It's actually a dup of flush_tlb_page() though it's -slightly- more
efficient on hash based processors.  We remove it and replace it by
a direct call to the hash flush code on those processors and to
flush_tlb_page() for everybody else.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This patch enables 32bit PPC's (with 36bit physical address space, e.g.
IBM/AMCC PPC44x) to run with >= 4GB of RAM. Mostly its just replacing types
(unsigned long -> phys_addr_t).

Tested on an AMCC Katmai with 4GB of DDR2.
Signed-off-by: NStefan Roese <sr@denx.de>
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>

Currently, the physical address is an unsigned long, but it should
be phys_addr_t in set_bat, [v/p]_mapped_by_bat.  Also, create a
macro that can convert a large physical address into the correct
format for programming the BAT registers.
Signed-off-by: NBecky Bruce <becky.bruce@freescale.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

We always use __initial_memory_limit as an address so rename it
to be clear.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

total_lowmem represents the amount of low memory, not the physical
address that low memory ends at.  If the start of memory is at 0 it
happens that total_lowmem can be used as both the size and the address
that lowmem ends at (or more specifically one byte beyond the end).

To make the code a bit more clear and deal with the case when the start of
memory isn't at physical 0, we introduce lowmem_end_addr that represents
one byte beyond the last physical address in the lowmem region.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

A number of users of PPC_MEMSTART (40x, ppc_mmu_32) can just always
use 0 as we don't support booting these kernels at non-zero physical
addresses since their exception vectors must be at 0 (or 0xfffx_xxxx).

For the sub-arches that support relocatable interrupt vectors
(book-e), it's reasonable to have memory start at a non-zero physical
address.  For those cases use the variable memstart_addr instead of
the #define PPC_MEMSTART since the only uses of PPC_MEMSTART are for
initialization and in the future we can set memstart_addr at runtime
to have a relocatable kernel.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

My changes to _tlbie to fix 4xx unfortunately broke 8xx build in a
couple of places.  This fixes it.

Spotted by Olof Johansson.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NVitaly Bordug <vitb@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

On 4xx CPUs, the current implementation of flush_tlb_page() uses
a low level _tlbie() assembly function that only works for the
current PID. Thus, invalidations caused by, for example, a COW
fault triggered by get_user_pages() from a different context will
not work properly, causing among other things, gdb breakpoints
to fail.

This patch adds a "pid" argument to _tlbie() on 4xx processors,
and uses it to flush entries in the right context. FSL BookE
also gets the argument but it seems they don't need it (their
tlbivax form ignores the PID when invalidating according to the
document I have).
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>

Using typedefs to rename structure types if frowned on by CodingStyle.
However, we do so for the hash PTE structure on both ppc32 (where it's
called "PTE") and ppc64 (where it's called "hpte_t").  On ppc32 we
also have such a typedef for the BATs ("BAT").

This removes this unhelpful use of typedefs, in the process
bringing ppc32 and ppc64 closer together, by using the name "struct
hash_pte" in both cases.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

APUS (the Amiga Power-Up System) is not supported under arch/powerpc
and it's unlikely it ever will be.  Therefore, this patch removes the
fragments of APUS support code from arch/powerpc which have been
copied from arch/ppc.

A few APUS references are left in asm-powerpc in .h files which are
still used from arch/ppc.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This rewrites pretty much from scratch the handling of MMIO and PIO
space allocations on powerpc64.  The main goals are:

 - Get rid of imalloc and use more common code where possible
 - Simplify the current mess so that PIO space is allocated and
   mapped in a single place for PCI bridges
 - Handle allocation constraints of PIO for all bridges including
   hot plugged ones within the 2GB space reserved for IO ports,
   so that devices on hotplugged busses will now work with drivers
   that assume IO ports fit in an int.
 - Cleanup and separate tracking of the ISA space in the reserved
   low 64K of IO space. No ISA -> Nothing mapped there.

I booted a cell blade with IDE on PIO and MMIO and a dual G5 so
far, that's it :-)

With this patch, all allocations are done using the code in
mm/vmalloc.c, though we use the low level __get_vm_area with
explicit start/stop constraints in order to manage separate
areas for vmalloc/vmap, ioremap, and PCI IOs.

This greatly simplifies a lot of things, as you can see in the
diffstat of that patch :-)

A new pair of functions pcibios_map/unmap_io_space() now replace
all of the previous code that used to manipulate PCI IOs space.
The allocation is done at mapping time, which is now called from
scan_phb's, just before the devices are probed (instead of after,
which is by itself a bug fix). The only other caller is the PCI
hotplug code for hot adding PCI-PCI bridges (slots).

imalloc is gone, as is the "sub-allocation" thing, but I do beleive
that hotplug should still work in the sense that the space allocation
is always done by the PHB, but if you unmap a child bus of this PHB
(which seems to be possible), then the code should properly tear
down all the HPTE mappings for that area of the PHB allocated IO space.

I now always reserve the first 64K of IO space for the bridge with
the ISA bus on it. I have moved the code for tracking ISA in a separate
file which should also make it smarter if we ever are capable of
hot unplugging or re-plugging an ISA bridge.

This should have a side effect on platforms like powermac where VGA IOs
will no longer work. This is done on purpose though as they would have
worked semi-randomly before. The idea at this point is to isolate drivers
that might need to access those and fix them by providing a proper
function to obtain an offset to the legacy IOs of a given bus.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This patch takes the definitions for the PPC44x MMU (a software loaded
TLB) from asm-ppc/mmu.h, cleans them up of things no longer necessary
in arch/powerpc and puts them in a new asm-powerpc/mmu_44x.h file.  It
also substantially simplifies arch/powerpc/mm/44x_mmu.c and makes a
couple of small fixes necessary for the 44x MMU code to build and work
properly in arch/powerpc.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

BenH's commit a741e679 in powerpc.git,
although (AFAICT) only intended to affect ppc64, also has side-effects
which break 44x.  I think 40x, 8xx and Freescale Book E are also
affected, though I haven't tested them.

The problem lies in unconditionally removing flush_tlb_pending() from
the versions of flush_tlb_mm(), flush_tlb_range() and
flush_tlb_kernel_range() used on ppc64 - which are also used the
embedded platforms mentioned above.

The patch below cleans up the convoluted #ifdef logic in tlbflush.h,
in the process restoring the necessary flushes for the software TLB
platforms.  There are three sets of definitions for the flushing
hooks: the software TLB versions (revised to avoid using names which
appear to related to TLB batching), the 32-bit hash based versions
(external functions) amd the 64-bit hash based versions (which
implement batching).

It also moves the declaration of update_mmu_cache() to always be in
tlbflush.h (previously it was in tlbflush.h except for PPC64, where it
was in pgtable.h).

Booted on Ebony (440GP) and compiled for 64-bit and 32-bit
multiplatform.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>