Add support for the Platform Facilities Option (PFO) to the VIO bus.
These devices have a separate root node in OpenFirmware which
requires additional parsing to map into the existing VIO device
structure fields. This adds the interface for PFO device drivers to
make synchronous hypervisor calls.
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This adds an update notifier mechanism for changes to properties in the
device tree. One use of this would be a device driver that needs to act
on changes to it's properties in the device tree after a live migration
or a dynamic activation that is triggered by updates to ofdt properties.
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The Platform Facilities Option (PFO) adds several new h_calls and
more return codes.
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
PPC_PTRACE_GETHWDBGINFO, PPC_PTRACE_SETHWDEBUG and PPC_PTRACE_DELHWDEBUG are
PowerPC specific ptrace flags that use the watchpoint register. While they are
targeted primarily towards BookE users, user-space applications such as GDB
have started using them for BookS too. This patch enables the use of generic
hardware breakpoint interfaces for these new flags.
Apart from the usual benefits of using generic hw-breakpoint interfaces, these
changes allow debuggers (such as GDB) to use a common set of ptrace flags for
their watchpoint needs and allow more precise breakpoint specification (length
of the variable can be specified).
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch changes the architecture vector to advertise support for a
lower minimum virtual processor entitled capacity. The default
minimum without this patch is 10%, this patch specifies 1%.
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
So we have another case of paca->irq_happened getting out of
sync with the HW irq state. This can happen when a perfmon
interrupt occurs while soft disabled, as it will return to a
soft disabled but hard enabled context while leaving a stale
PACA_IRQ_HARD_DIS flag set.
This patch fixes it, and also adds a test for the condition
of those flags being out of sync in arch_local_irq_restore()
when CONFIG_TRACE_IRQFLAGS is enabled.
This helps catching those gremlins faster (and so far I
can't seem see any anymore, so that's good news).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Pull KVM fixes from Avi Kivity:
"Two asynchronous page fault fixes (one guest, one host), a powerpc
page refcount fix, and an ia64 build fix."
* git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: ia64: fix build due to typo
KVM: PPC: Book3S HV: Fix refcounting of hugepages
KVM: Do not take reference to mm during async #PF
KVM: ensure async PF event wakes up vcpu from halt
Pull powerpc fixes from Benjamin Herrenschmidt:
"Here are a couple of last minute fixes for 3.4 for regressions
introduced by my rewrite of the lazy irq masking code."
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc/irq: Make alignment & program interrupt behave the same
powerpc/irq: Fix bug with new lazy IRQ handling code
'TIF_RUNLATCH' is already dropped from
commit fe1952fc0a
powerpc: Rework runlatch code
So '_TIF_RUNLATCH' should be removed as well.
Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Alignment was the last user of the ENABLE_INTS macro, which we can
now remove. All non-syscall exceptions now disable interrupts on
entry, they get re-enabled conditionally from C code. Don't
unconditionally re-enable in program check either, check the
original context.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We had a case where we could turn on hard interrupts while
leaving the PACA_IRQ_HARD_DIS bit set in the PACA. This can
in turn cause a BUG_ON() to hit in __check_irq_replay() due
to interrupt state getting out of sync.
The assembly code was also way too convoluted. Instead, we
now leave it to the C code to do the right thing which ends
up being smaller and more readable.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The H_REGISTER_VPA hcall implementation in HV Power KVM needs to pin some
guest memory pages into host memory so that they can be safely accessed
from usermode. It does this used get_user_pages_fast(). When the VPA is
unregistered, or the VCPUs are cleaned up, these pages are released using
put_page().
However, the get_user_pages() is invoked on the specific memory are of the
VPA which could lie within hugepages. In case the pinned page is huge,
we explicitly find the head page of the compound page before calling
put_page() on it.
At least with the latest kernel, this is not correct. put_page() already
handles finding the correct head page of a compound, and also deals with
various counts on the individual tail page which are important for
transparent huge pages. We don't support transparent hugepages on Power,
but even so, bypassing this count maintenance can lead (when the VM ends)
to a hugepage being released back to the pool with a non-zero mapcount on
one of the tail pages. This can then lead to a bad_page() when the page
is released from the hugepage pool.
This removes the explicit compound_head() call to correct this bug.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
Fix a build error when -Werror is set:
arch/powerpc/sysdev/ppc4xx_msi.c: In function ‘ppc4xx_setup_pcieh_hw’:
arch/powerpc/sysdev/ppc4xx_msi.c:178:2: error: right shift count >= width of type [-Werror]
Signed-off-by: Josh Boyer <jwboyer@gmail.com>
Pull networking fixes from David Miller:
1) Transfer padding was wrong for full-speed USB in ASIX driver, fix
from Ingo van Lil.
2) Propagate the negative packet offset fix into the PowerPC BPF JIT.
From Jan Seiffert.
3) dl2k driver's private ioctls were letting unprivileged tasks make
MII writes and other ugly bits like that. Fix from Jeff Mahoney.
4) Fix TX VLAN and RX packet drops in ucc_geth, from Joakim Tjernlund.
5) OOPS and network namespace fixes in IPVS from Hans Schillstrom and
Julian Anastasov.
6) Fix races and sleeping in locked context bugs in drop_monitor, from
Neil Horman.
7) Fix link status indication in smsc95xx driver, from Paolo Pisati.
8) Fix bridge netfilter OOPS, from Peter Huang.
9) L2TP sendmsg can return on error conditions with the socket lock
held, oops. Fix from Sasha Levin.
10) udp_diag should return meaningful values for socket memory usage,
from Shan Wei.
11) Eric Dumazet is so awesome he gets his own section:
Socket memory cgroup code (I never should have applied those
patches, grumble...) made erroneous changes to
sk_sockets_allocated_read_positive(). It was changed to
use percpu_counter_sum_positive (which requires BH disabling)
instead of percpu_counter_read_positive (which does not).
Revert back to avoid crashes and lockdep warnings.
Adjust the default tcp_adv_win_scale and tcp_rmem[2] values
to fix throughput regressions. This is necessary as a result
of our more precise skb->truesize tracking.
Fix SKB leak in netem packet scheduler.
12) New device IDs for various bluetooth devices, from Manoj Iyer,
AceLan Kao, and Steven Harms.
13) Fix command completion race in ipw2200, from Stanislav Yakovlev.
14) Fix rtlwifi oops on unload, from Larry Finger.
15) Fix hard_mtu when adjusting hard_header_len in smsc95xx driver.
From Stephane Fillod.
16) ehea driver registers it's IRQ before all the necessary state is
setup, resulting in crashes. Fix from Thadeu Lima de Souza
Cascardo.
17) Fix PHY connection failures in davinci_emac driver, from Anatolij
Gustschin.
18) Missing break; in switch statement in bluetooth's
hci_cmd_complete_evt(). Fix from Szymon Janc.
19) Fix queue programming in iwlwifi, from Johannes Berg.
20) Interrupt throttling defaults not being actually programmed into the
hardware, fix from Jeff Kirsher and Ying Cai.
21) TLAN driver SKB encoding in descriptor busted on 64-bit, fix from
Benjamin Poirier.
22) Fix blind status block RX producer pointer deref in TG3 driver, from
Matt Carlson.
23) Promisc and multicast are busted on ehea, fixes from Thadeu Lima de
Souza Cascardo.
24) Fix crashes in 6lowpan, from Alexander Smirnov.
25) tcp_complete_cwr() needs to be careful to not rewind the CWND to
ssthresh if ssthresh has the "infinite" value. Fix from Yuchung
Cheng.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (81 commits)
sungem: Fix WakeOnLan
tcp: change tcp_adv_win_scale and tcp_rmem[2]
net: l2tp: unlock socket lock before returning from l2tp_ip_sendmsg
drop_monitor: prevent init path from scheduling on the wrong cpu
usbnet: fix failure handling in usbnet_probe
usbnet: fix leak of transfer buffer of dev->interrupt
ucc_geth: Add 16 bytes to max TX frame for VLANs
net: ucc_geth, increase no. of HW RX descriptors
netem: fix possible skb leak
sky2: fix receive length error in mixed non-VLAN/VLAN traffic
sky2: propogate rx hash when packet is copied
net: fix two typos in skbuff.h
cxgb3: Don't call cxgb_vlan_mode until q locks are initialized
ixgbe: fix calling skb_put on nonlinear skb assertion bug
ixgbe: Fix a memory leak in IEEE DCB
igbvf: fix the bug when initializing the igbvf
smsc75xx: enable mac to detect speed/duplex from phy
smsc75xx: declare smsc75xx's MII as GMII capable
smsc75xx: fix phy interrupt acknowledge
smsc75xx: fix phy init reset loop
...
This patch consists of:
- Enable PCI MSI as default for Bluestone board
- Change definition of number of MSI interrupts as it depends on SoC
- Fix returning ENODEV as finding MSI node
- Fix MSI physical high and low address
- Keep MSI data logically
Signed-off-by: Mai La <mla@apm.com>
Signed-off-by: Josh Boyer <jwboyer@gmail.com>
Now that we have KEXEC and relocatable kernel working on 47x (!SMP)
enable CRASH_DUMP.
Signed-off-by: Suzuki K. Poulose <suzuki@in.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@gmail.com>
This patch adds support for creating 1:1 mapping for the PPC_47x during
a KEXEC. The implementation is similar to that of the PPC440x which is
described here :
http://patchwork.ozlabs.org/patch/104323/
PPC_47x MMU :
The 47x uses Unified TLB 1024 entries, with 4-way associative mapping
(4 x 256 entries). The index to be used is calculated by the MMU by
hashing the PID, EPN and TS. The software can choose to specify the way
by setting bit 0(enable way select) and the way in bits 1-2 in the TLB
Word 0.
Implementation:
The patch erases all the UTLB entries which includes the tlb covering
the mapping for our code. The shadow TLB caches the mapping for the
running code which helps us to continue the execution until we do
isync/rfi. We then create a tmp mapping for the current code in the
other address space (TS) and switch to it.
Then we create a 1:1 mapping(EPN=RPN) for 0-2GiB in the original
address space and switch to the new mapping.
TODO: Add SMP support.
Signed-off-by: Suzuki K. Poulose <suzuki@in.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@gmail.com>
Initialize the PID register with kernel pid (0) before we start
setting the TLB mapping for KEXEC. Also set the MMUCR[TID] to kernel
PID.
This was spotted while testing the kexec on ISS for 47x. ISS doesn't
return a successful tlbsx for a kernel address with PID set to a user PID.
Though the hardware/qemu/simics work fine.
This patch is harmless and initializes the PID to 0 (kernel PID) which
is usually the case during a normal kernel boot. This would fix the kexec
on ISS for 440. I have tested this patch on sequoia board.
Signed-off-by: Suzuki K Poulose <suzuki@in.ibm.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Josh Boyer <jwboyer@gmail.com>
Now the helper function from filter.c for negative offsets is exported,
it can be used it in the jit to handle negative offsets.
First modify the asm load helper functions to handle:
- know positive offsets
- know negative offsets
- any offset
then the compiler can be modified to explicitly use these helper
when appropriate.
This fixes the case of a negative X register and allows to lift
the restriction that bpf programs with negative offsets can't
be jited.
Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Jan Seiffert <kaffeemonster@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
PowerPC has non standard getregs calls that only dump the GPRs or
FPRs and have their arguments reversed. commit e17666ba48 (ptrace
updates & new, better requests) in 2.6.3 deprecated them and introduced
more standard versions.
It's been about 5 years and I know of no users of the old calls so
lets remove them.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When we get an EEH error we just print a backtrace with dump_stack
which is rather cryptic. We really should print something before
spewing out the backtrace.
Also switch from dump_stack to WARN so we get more information about
the fail - what modules were loaded, what process was running etc.
This was useful information when debugging a recent EEH subsystem bug.
The standard WARN output should also get picked up by monitoring
tools like kerneloops.
The register dump is of questionable value here but I figured it was
better to use something standard and not roll my own.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add a menu to select various 64-bit CPU targets for gcc. We
default to -mtune=power7 and if gcc doesn't understand that we
fallback to -mtune=power4.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Now we require gcc 4.0 on 64-bit we can remove the pre gcc 4.0
-maltivec workaround.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Older versions of gcc had issues with using -maltivec together with
-mcpu of a non altivec capable CPU. We work around it by specifying
-mcpu=970, but the logic is complicated.
In preparation for adding more -mcpu targets, remove the workaround
and just require gcc 4.0 for 64-bit builds.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Remove CONFIG_POWER4_ONLY, the option is badly named and only does two
things:
- It wraps the MMU segment table code. With feature fixups there is
little downside to compiling this in.
- It uses the newer mtocrf instruction in various assembly functions.
Instead of making this a compile option just do it at runtime via
a feature fixup.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This causes i2c-powermac to register i2c devices exposed in the
device-tree, enabling new-style probing of devices.
Note that we prefix the IDs with "MAC," in order to prevent the
generic drivers from matching. This is done on purpose as we only
want drivers specifically tested/designed to operate on powermacs
to match.
This removes the special case we had for the AMS driver, and updates
the driver's match table instead.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add two optimisations to enable_kernel_altivec:
- enable_kernel_altivec has already determined if we need to
save the previous task's state but we call giveup_altivec
in both cases, requiring an extra branch in giveup_altivec. Create
giveup_altivec_notask which only turns on the VMX bit in the
MSR.
- We write the VMX MSR bit each time we call enable_kernel_altivec
even it was already set. Check the bit and branch out if we have
already set it. The classic case for this is vectored IO
where we have to copy multiple buffers to or from userspace.
The following testcase was used to confirm this patch improves
performance:
http://ozlabs.org/~anton/junkcode/copy_to_user.c
Since the current breakpoint for using VMX in copy_tofrom_user is
4096 bytes, I'm using buffers of 4096 + 1 cacheline (4224) bytes.
A benchmark of 16 entry readvs (-s 16):
time copy_to_user -l 4224 -s 16 -i 1000000
completes 5.2% faster on a POWER7 PS700.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Use an empty inline instead of an empty function to implement
giveup_altivec on book3e CPUs, similar to flush_altivec_to_thread.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reformat lppaca.h to match Linux coding standards.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Remove all the iseries specific fields in the lppaca.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We have a union containing fields from the old iseries hypervisor
that has been reused for the cede latency hint. Since we no
longer support iseries, remove the union completely.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
At the moment system call entry looks like:
crclr so
...
mfcr r9
...
std r9,_CCR(r1)
commit bd19c8994a ([POWERPC] system call micro optimisation) put
some space between the crclr and mfcr in order to avoid a stall.
There is still a stall seen between the mfcr and std. We can avoid
the crclr by doing it in a GPR with rlwinm which gives us more room
to better schedule the sequence.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The count register is volatile so we don't need to preserve it.
Store zero to the entry in the exception frame.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The XER is a volatile register so there is no need to save and restore
it over a system call - zero it out in the exception stack frame
instead.
This should fix a 5 cycle stall of the mfxer/std seen on POWER7.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
syscall_dotrace_cont and syscall_error_cont tend to complicate perf
output so make them local.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Recently, Ryan Wang tried to compile PPC pSeries platform without
CONFIG_EEH and eventually run into errors. Nishanth Aravamudan
helped to narrow down the root cause. Actually, the pSeries platform
depends on CONFIG_EEH heavily and that won't work properly without
EEH support.
According to Ben's suggestion, the patch make CONFIG_EEH invisible
and keep it as always selected on pSeries platform.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The switch from using irq_map to irq_alloc_desc*() for managing irq
number allocations introduced new bugs in some of the powerpc
interrupt code. Several functions rely on the value of NR_IRQS to
determine the maximum irq number that could get allocated. However,
with sparse_irq and using irq_alloc_desc*() the maximum possible irq
number is now specified with 'nr_irqs' which may be a number larger
than NR_IRQS. This has caused breakage on powermac when
CONFIG_NR_IRQS is set to 32.
This patch removes most of the direct references to NR_IRQS in the
powerpc code and replaces them with either a nr_irqs reference or by
using the common for_each_irq_desc() macro. The powerpc-specific
for_each_irq() macro is removed at the same time.
Also, the Cell axon_msi driver is refactored to remove the global
build assumption on the size of NR_IRQS and instead add a limit to the
maximum irq number when calling irq_domain_add_nomap().
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The mpc8xx driver uses a reference to NR_IRQS that is buggy. It uses
NR_IRQs for the array size of the ppc_cached_irq_mask bitmap, but
NR_IRQs could be smaller than the number of hardware irqs that
ppc_cached_irq_mask tracks.
Also, while fixing that problem, it became apparent that the interrupt
controller only supports 32 interrupt numbers, but it is written as if
it supports multiple register banks which is more complicated.
This patch pulls out the buggy reference to NR_IRQs and fixes the size
of the ppc_cached_irq_mask to match the number of HW irqs. It also
drops the now-unnecessary code since ppc_cached_irq_mask is no longer
an array.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Pull build fixes for less mainstream architectures from Paul Gortmaker:
"These are fixes for frv(1), blackfin(2), powerpc(1) and xtensa(4).
Fortunately the touches are nearly all specific to files just used by
the arch in question. The two touches to shared/common files
[kernel/irq/debug.h and drivers/pci/Makefile] are trivial to assess as
no risk to anyone.
Half of them relate to xtensa directly. It was only when I fixed the
last xtensa issue that I realized that the arch has been broken for a
significant time, and isn't a specific v3.4 regression. So if you
wanted, we could leave xtensa lying bleeding in the street for a
couple more weeks and queue those for 3.5. But given they are no risk
to anyone outside of xtensa, I figured to just leave them in.
If you are OK with taking the xtensa fixes, then please pull to get:
- one last implicit include uncovered by system.h that is in a file
specific to just one powerpc defconfig. (I'd sync'd with BenH).
- fix an oversight in the PCI makefile where shared code wasn't being
compiled for ARCH=frv
- fix a missing include for GPIO in blackfin framebuffer.
- audit and tag endif in blackfin ezkit board file, in order to find
and fix the misplaced endif masking a block of code.
- fix irq/debug.h choice of temporary macro names to be more internal
so they don't conflict with names used by xtensa.
- fix a reference to an undeclared local var in xtensa's signal.c
- fix an implicit bug.h usage in xtensa's asm/io.h uncovered by my
removing bug.h from kernel.h
- fix xtensa to properly indicate it is using asm-generic/hardirq.h
in order to resolve the link error - undefined ack_bad_irq
The xtensa still fails final link as my latest binutils does something
evil when ld forward-relocates unlikely() blocks, but in theory people
who have older/valid toolchains could now use the thing."
* 'for-v3.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux:
xtensa: fix build fail on undefined ack_bad_irq
blackfin: fix ifdef fustercluck in mach-bf538/boards/ezkit.c
blackfin: fix compile error in bfin-lq035q1-fb.c
pci: frv architecture needs generic setup-bus infrastructure
irq: hide debug macros so they don't collide with others.
xtensa: fix build error in xtensa/include/asm/io.h
xtensa: fix build failure in xtensa/kernel/signal.c
powerpc: fix system.h fallout in sysdev/scom.c [chroma_defconfig]
The dependency on hotplug memory was removed, so
remove the dependency in the Kconfig.
Signed-off-by: Andre Heider <a.heider@gmail.com>
Signed-off-by: Geoff Levand <geoff@infradead.org>
Real mode memory can be limited and runs out quickly as memory is allocated
during kernel startup. Having the highmem available sooner fixes this.
This change simplifies the memory management code by converting from hotplug
memory to logical memory blocks.
Signed-off-by: Hector Martin <hector@marcansoft.com>
Signed-off-by: Andre Heider <a.heider@gmail.com>
Signed-off-by: Geoff Levand <geoff@infradead.org>
Use any preallocated highmem region setup by the bootloader.
This implementation only checks for the existance of a single
region at region_index=0.
This feature allows the bootloader to preallocate highmem
regions and pass the region locations to the kernel through
the repository. Preallocated regions can be used to hold the
initrd or other large data. If no region info exists, the
kernel retains the old behavior and attempts to allocate the
highmem region itself.
Based on Hector Martin's patch "Get lv1 high memory region from
devtree".
CC: Hector Martin <hector@marcansoft.com>
Signed-off-by: Andre Heider <a.heider@gmail.com>
CC: Nathan Whitehorn <nwhitehorn@freebsd.org>
Signed-off-by: Geoff Levand <geoff@infradead.org>
Add repository helper routines to read highmem region info.
Bootloaders that preallocate highmem regions must place the
region info into the repository at these well known nodes.
These routines allow second stage kernles to read the region
info from those nodes.
Signed-off-by: Andre Heider <a.heider@gmail.com>
CC: Nathan Whitehorn <nwhitehorn@freebsd.org>
Signed-off-by: Geoff Levand <geoff@infradead.org>
