Commit Graph

4028 Commits

Author SHA1 Message Date
Sukadev Bhattiprolu
5239af679a powerpc/powernv/vas: Define vas_tx_win_open()
Define an interface to open a VAS send window. This interface is
intended to be used the Nest Accelerator (NX) driver(s) to open
a send window and use it to submit compression/encryption requests
to a VAS receive window.

The receive window, identified by the [vasid, cop] parameters, must
already be open in VAS (i.e connected to an NX engine).

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:37 +10:00
Sukadev Bhattiprolu
98271d4198 powerpc/powernv/vas: Define vas_win_close() interface
Define the vas_win_close() interface which should be used to close a
send or receive windows.

While the hardware configurations required to open send and receive
windows differ, the configuration to close a window is the same for
both. So we use a single interface to close the window.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:37 +10:00
Sukadev Bhattiprolu
62c4eda4fa powerpc/powernv/vas: Define vas_rx_win_open() interface
Define the vas_rx_win_open() interface. This interface is intended to
be used by the Nest Accelerator (NX) driver(s) to setup receive
windows for one or more NX engines (which implement compression &
encryption algorithms in the hardware).

Follow-on patches will provide an interface to close the window and to
open a send window that kernel subsystems can use to access the NX
engines.

The interface to open a receive window is expected to be invoked for
each instance of VAS in the system.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:36 +10:00
Sukadev Bhattiprolu
b6622a339e powerpc/powernv: Move GET_FIELD/SET_FIELD to vas.h
Move the GET_FIELD and SET_FIELD macros to vas.h as VAS and other
users of VAS, including NX-842 can use those macros.

There is a lot of related code between the VAS/NX kernel drivers
and skiboot. For consistency, switch the order of parameters in
SET_FIELD to match the order in skiboot.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Reviewed-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:20 +10:00
Sukadev Bhattiprolu
967689141e powerpc/powernv/vas: Define macros, register fields and structures
Define macros for the VAS hardware registers and bit-fields as well
as couple of data structures needed by the VAS driver.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
[mpe: Fixup include guard to use _ASM_POWERPC_VAS_H]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:17 +10:00
Alexey Kardashevskiy
f1e08232ed powerpc/pci: Remove OF node back pointer from pci_dn
The check_req() helper uses pci_get_pdn() to get an OF node pointer.
pci_get_pdn() returns a pci_dn pointer which either:
1) from the OF node returned by pci_device_to_OF_node();
2) from the parent child_list where entries don't have OF node pointers.
Since check_req() does not care about 2), it can call
pci_device_to_OF_node() directly, hence the change.

The find_pe_dn() helper uses embedded pci_dn to get an OF node which is
also stored in edev->pdev so let's take a shortcut and call
pci_device_to_OF_node() directly.

With these 2 changes, we can finally get rid of the OF node back pointer.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:12 +10:00
Alexey Kardashevskiy
405b33a76d powerpc/eeh: Remove unnecessary config_addr from eeh_dev
The eeh_dev struct hold a config space address of an associated node
and the very same address is also stored in the pci_dn struct which
is always present during the eeh_dev lifetime.

This uses bus:devfn directly from pci_dn instead of cached and packed
config_addr.

Since config_addr is made from device's bus:dev.fn, there is no point
in keeping it in the debugfs either so remove that too.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:09 +10:00
Alexey Kardashevskiy
69672bd748 powerpc/eeh: Remove unnecessary pointer to phb from eeh_dev
The eeh_dev struct already holds a pointer to pci_dn which it does not
exist without and pci_dn itself holds the very same pointer so just
use it.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:09 +10:00
Alexey Kardashevskiy
8bae6a2319 powerpc/eeh: Reduce to one the number of places where edev is allocated
arch/powerpc/kernel/eeh_dev.c:57 is the only legit place where edev
is allocated; other 2 places allocate it on stack and in the heap for
a very short period of time to use eeh_pe_get() as takes edev.

This changes eeh_pe_get() to receive required parameters explicitly.

This removes unnecessary temporary allocation of edev.

This uses the "pe_no" name instead of the "pe_config_addr" name as
it actually is a PE number and not a config space address as it seemed.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:08 +10:00
Nicholas Piggin
6fcd6baa90 powerpc/powernv: Use kernel crash path for machine checks
There are quite a few machine check exceptions that can be caused by
kernel bugs. To make debugging easier, use the kernel crash path in
cases of synchronous machine checks that occur in kernel mode, if that
would not result in the machine going straight to panic or crash dump.

There is a downside here that die()ing the process in kernel mode can
still leave the system unstable. panic_on_oops will always force the
system to fail-stop, so systems where that behaviour is important will
still do the right thing.

As a test, when triggering an i-side 0111b error (ifetch from foreign
address) in kernel mode process context on POWER9, the kernel currently
dies quickly like this:

  Severe Machine check interrupt [Not recovered]
    NIP [ffff000000000000]: 0xffff000000000000
    Initiator: CPU
    Error type: Real address [Instruction fetch (foreign)]
  [  127.426651616,0] OPAL: Reboot requested due to Platform error.
      Effective[  127.426693712,3] OPAL: Reboot requested due to Platform error. address: ffff000000000000
  opal: Reboot type 1 not supported
  Kernel panic - not syncing: PowerNV Unrecovered Machine Check
  CPU: 56 PID: 4425 Comm: syscall Tainted: G   M            4.12.0-rc1-13857-ga4700a261072-dirty #35
  Call Trace:
  [  128.017988928,4] IPMI: BUG: Dropping ESEL on the floor due to
    buggy/mising code in OPAL for this BMC
    Rebooting in 10 seconds..
  Trying to free IRQ 496 from IRQ context!

After this patch, the process is killed and the kernel continues with
this message, which gives enough information to identify the offending
branch (i.e., with CFAR):

  Severe Machine check interrupt [Not recovered]
    NIP [ffff000000000000]: 0xffff000000000000
    Initiator: CPU
    Error type: Real address [Instruction fetch (foreign)]
      Effective address: ffff000000000000
  Oops: Machine check, sig: 7 [#1]
  SMP NR_CPUS=2048
  NUMA
  PowerNV
  Modules linked in: iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 ...
  CPU: 22 PID: 4436 Comm: syscall Tainted: G   M            4.12.0-rc1-13857-ga4700a261072-dirty #36
  task: c000000932300000 task.stack: c000000932380000
  NIP: ffff000000000000 LR: 00000000217706a4 CTR: ffff000000000000
  REGS: c00000000fc8fd80 TRAP: 0200   Tainted: G   M             (4.12.0-rc1-13857-ga4700a261072-dirty)
  MSR: 90000000001c1003 <SF,HV,ME,RI,LE>
    CR: 24000484  XER: 20000000
  CFAR: c000000000004c80 DAR: 0000000021770a90 DSISR: 0a000000 SOFTE: 1
  GPR00: 0000000000001ebe 00007fffce4818b0 0000000021797f00 0000000000000000
  GPR04: 00007fff8007ac24 0000000044000484 0000000000004000 00007fff801405e8
  GPR08: 900000000280f033 0000000024000484 0000000000000000 0000000000000030
  GPR12: 9000000000001003 00007fff801bc370 0000000000000000 0000000000000000
  GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR24: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR28: 00007fff801b0000 0000000000000000 00000000217707a0 00007fffce481918
  NIP [ffff000000000000] 0xffff000000000000
  LR [00000000217706a4] 0x217706a4
  Call Trace:
  Instruction dump:
  XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
  XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:04 +10:00
Nicholas Piggin
b746e3e01e powerpc/powernv: Flush console before platform error reboot
Unrecovered MCE and HMI errors are sent through a special restart OPAL
call to log the platform error. The downside is that they don't go
through normal Linux crash paths, so they don't give much information
to the Linux console.

Change this by providing a special crash function which does some of
the console flushing from the panic() path before calling firmware to
reboot.

The downside of this is a little more code to execute before reaching
the firmware reboot. However in practice, it's critical to get the
Linux console messages output in order to debug a problem. So this is
a desirable tradeoff.

Note on the implementation: It is difficult to plumb a custom reboot
handler into the panic path, because panic does a little bit too much
work. For example, it will try to delay with the timebase, but that
may be corrupted in some cases resulting in a hang without reaching
the platform reboot. Another problem is that panic can invoke the
crash dump code which is not what we want in the case of a hardware
platform error. Long-term the best solution will be to rework the
panic path so it can be suitable for this kind of panic, but for now
we just duplicate a bit of the code.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:03 +10:00
Nicholas Piggin
a3b2cb30f2 powerpc: Do not call ppc_md.panic in fadump panic notifier
If fadump is not registered, and no other crash or debug handlers are
registered, the powerpc panic handler stops the guest before the
generic panic code can push out debug information to the console.

Currently, system reset injection causes the guest to silently stop.

Stop calling ppc_md.panic in the panic notifier. crash_fadump already
does rtas_os_term() to terminate the guest if fadump is registered.

Remove ppc_md.panic. Move fadump panic notifier into fadump code.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:01 +10:00
Nicholas Piggin
70412c55d4 powerpc/64: Fix watchdog configuration regressions
This fixes a couple more bits of fallout from the new hard lockup watchdog
patch.

It restores the required hw_nmi_get_sample_period() function for the
perf watchdog, and removes some function declarations on 64e that are only
defined for 64s. This fixes the 64e build when the hardlockup detector is
enabled.

It restores the default behaviour of disabling the perf watchdog, and also
fixes disabling the 64s watchdog when running as a guest.

Fixes: 2104180a53 ("powerpc/64s: implement arch-specific hardlockup watchdog")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-31 14:26:00 +10:00
Nicholas Piggin
aafc8a8300 powerpc/64s: Move IDLE_STATE_ENTER_SEQ[_NORET] into idle_book3s.S
This macro is only used in idle_book3s.S, move it in there and add a
more descriptive comment.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out of larger patch and write change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-29 21:38:47 +10:00
Michael Ellerman
82b7fcc005 Merge branch 'topic/ppc-kvm' into next
Merge Nicks commit to rework the KVM thread management, shared with the
KVM tree via the ppc-kvm topic branch.
2017-08-29 21:26:30 +10:00
Nicholas Piggin
94a04bc25a KVM: PPC: Book3S HV: POWER9 does not require secondary thread management
POWER9 CPUs have independent MMU contexts per thread, so KVM does not
need to quiesce secondary threads, so the hwthread_req/hwthread_state
protocol does not have to be used. So patch it away on POWER9, and patch
away the branch from the Linux idle wakeup to kvm_start_guest that is
never used.

Add a warning and error out of kvmppc_grab_hwthread in case it is ever
called on POWER9.

This avoids a hwsync in the idle wakeup path on POWER9.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
[mpe: Use WARN(...) instead of WARN_ON()/pr_err(...)]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-29 14:48:59 +10:00
Benjamin Herrenschmidt
3a2df3798d powerpc/mm: Make switch_mm_irqs_off() out of line
It's too big to be inline, there is no reason to keep it
that way.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Rework to incorporate the comment changes via fixes branch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-23 22:48:51 +10:00
Benjamin Herrenschmidt
a619e59c07 powerpc/mm: Optimize detection of thread local mm's
Instead of comparing the whole CPU mask every time, let's
keep a counter of how many bits are set in the mask. Thus
testing for a local mm only requires testing if that counter
is 1 and the current CPU bit is set in the mask.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-23 22:28:38 +10:00
Benjamin Herrenschmidt
058ccc3465 powerpc/mm: Avoid double irq save/restore in activate_mm
It calls switch_mm() which already does the irq save/restore
these days.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-23 22:27:44 +10:00
Benjamin Herrenschmidt
43ed84a891 powerpc/mm: Move pgdir setting into a helper
Makes switch_mm_irqs_off() a bit more readable

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-23 22:27:42 +10:00
Michael Ellerman
15c659ff9d Merge branch 'fixes' into next
There's a non-trivial dependency between some commits we want to put in
next and the KVM prefetch work around that went into fixes. So merge
fixes into next.
2017-08-23 22:20:10 +10:00
Benjamin Herrenschmidt
1a92a80ad3 powerpc/mm: Ensure cpumask update is ordered
There is no guarantee that the various isync's involved with
the context switch will order the update of the CPU mask with
the first TLB entry for the new context being loaded by the HW.

Be safe here and add a memory barrier to order any subsequent
load/store which may bring entries into the TLB.

The corresponding barrier on the other side already exists as
pte updates use pte_xchg() which uses __cmpxchg_u64 which has
a sync after the atomic operation.

Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add comments in the code]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-18 13:07:16 +10:00
Aneesh Kumar K.V
fa4531f753 powerpc/mm: Don't send IPI to all cpus on THP updates
Now that we made sure that lockless walk of linux page table is mostly
limitted to current task(current->mm->pgdir) we can update the THP
update sequence to only send IPI to CPUs on which this task has run.
This helps in reducing the IPI overload on systems with large number
of CPUs.

WRT kvm even though kvm is walking page table with vpc->arch.pgdir,
it is done only on secondary CPUs and in that case we have primary CPU
added to task's mm cpumask. Sending an IPI to primary will force the
secondary to do a vm exit and hence this mm cpumask usage is safe
here.

WRT CAPI, we still end up walking linux page table with capi context
MM. For now the pte lookup serialization sends an IPI to all CPUs in
CPI is in use. We can further improve this by adding the CAPI
interrupt handling CPU to task mm cpumask. That will be done in a
later patch.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-17 23:31:13 +10:00
Michael Ellerman
8434f0892e Merge branch 'topic/ppc-kvm' into next
Bring in the commit to rename find_linux_pte_or_hugepte() which touches
arch and KVM code, and might need to be merged with the kvmppc tree to
avoid conflicts.
2017-08-17 23:14:17 +10:00
Aneesh Kumar K.V
94171b19c3 powerpc/mm: Rename find_linux_pte_or_hugepte()
Add newer helpers to make the function usage simpler. It is always
recommended to use find_current_mm_pte() for walking the page table.
If we cannot use find_current_mm_pte(), it should be documented why
the said usage of __find_linux_pte() is safe against a parallel THP
split.

For now we have KVM code using __find_linux_pte(). This is because kvm
code ends up calling __find_linux_pte() in real mode with MSR_EE=0 but
with PACA soft_enabled = 1. We may want to fix that later and make
sure we keep the MSR_EE and PACA soft_enabled in sync. When we do that
we can switch kvm to use find_linux_pte().

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-17 23:13:46 +10:00
Naveen N. Rao
694fc88ce2 powerpc/string: Implement optimized memset variants
Based on Matthew Wilcox's patches for other architectures.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-17 23:04:35 +10:00
Dou Liyang
7baebe54a6 powerpc/topology: Remove the unused parent_node() macro
Commit a7be6e5a7f ("mm: drop useless local parameters of
__register_one_node()") removes the last user of parent_node().

The parent_node() macro in POWERPC platform is unnecessary.

Remove it for cleanup.

Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16 21:12:41 +10:00
Aneesh Kumar K.V
4ae279c2c9 powerpc/mm/hugetlb: Allow runtime allocation of 16G.
Now that we have GIGANTIC_PAGE enabled on powerpc, use this for 16G hugepages
with hash translation mode. Depending on the total system memory we have, we may
be able to allocate 16G hugepages runtime. This also remove the hugetlb setup
difference between hash/radix translation mode.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16 14:56:13 +10:00
Aneesh Kumar K.V
79cc38ded1 powerpc/mm/hugetlb: Add support for reserving gigantic huge pages via kernel command line
With commit aa888a7497 ("hugetlb: support larger than MAX_ORDER") we added
support for allocating gigantic hugepages via kernel command line. Switch
ppc64 arch specific code to use that.

W.r.t FSL support, we now limit our allocation range using BOOTMEM_ALLOC_ACCESSIBLE.

We use the kernel command line to do reservation of hugetlb pages on powernv
platforms. On pseries hash mmu mode the supported gigantic huge page size is
16GB and that can only be allocated with hypervisor assist. For pseries the
command line option doesn't do the allocation. Instead pseries does gigantic
hugepage allocation based on hypervisor hint that is specified via
"ibm,expected#pages" property of the memory node.

Cc: Scott Wood <oss@buserror.net>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16 14:56:12 +10:00
Christophe Leroy
ca8afd4046 powerpc/hugetlb: fix page rights verification in gup_hugepte()
gup_hugepte() checks if pages are present and readable, and
when  'write' is set, also checks if the pages are writable.

Initially this was done by checking if _PAGE_PRESENT and
_PAGE_READ were set. In addition, _PAGE_WRITE was verified for write
accesses.

The problem is that we have to handle the three following cases:
1/ The target defines __PAGE_READ and __PAGE_WRITE
2/ The target defines __PAGE_RW
3/ The target defines __PAGE_RO

In case 1/, this is obvious
In case 2/, __PAGE_READ is defined as 0 and __PAGE_WRITE as __PAGE_RW
so it works as well.
But in case 3, __PAGE_RW is defined as 0, which means __PAGE_WRITE is 0
and then the test returns true (page writable) in all cases.

A first correction was attempted in commit 6b8cb66a6a ("powerpc: Fix
usage of _PAGE_RO in hugepage"), but that fix is wrong:
instead of checking that the page is writable when write is requested,
it checks that the page is NOT writable when write is NOT requested.

This patch adds a new pte_read() helper to check whether a page is
readable or not. This avoids handling all possible cases in
gup_hugepte().

Then gup_hugepte() is modified to use pte_present(), pte_read()
and pte_write() instead of the raw flags.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:58 +10:00
Christophe Leroy
4cfac2f9c7 powerpc/mm: Simplify __set_fixmap()
__set_fixmap() uses __fix_to_virt() then does the boundary checks
by it self. Instead, we can use fix_to_virt() which does the
verification at build time. For this, we need to use it inline
so that GCC can see the real value of idx at buildtime.

In the meantime, we remove the 'fixmaps' variable.
This variable is set but has never been used from the beginning
(commit 2c419bdeca ("[POWERPC] Port fixmap from x86 and use
for kmap_atomic"))

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:58 +10:00
Christophe Leroy
86b19520e7 powerpc/mm: declare some local functions static
get_pteptr() and __mapin_ram_chunk() are only used locally,
so define them static

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:57 +10:00
Christophe Leroy
3184cc4b6f powerpc/mm: Fix kernel RAM protection after freeing unused memory on PPC32
As seen below, allthough the init sections have been freed, the
associated memory area is still marked as executable in the
page tables.

~ dmesg
[    5.860093] Freeing unused kernel memory: 592K (c0570000 - c0604000)

~ cat /sys/kernel/debug/kernel_page_tables
---[ Start of kernel VM ]---
0xc0000000-0xc0497fff        4704K  rw  X  present dirty accessed shared
0xc0498000-0xc056ffff         864K  rw     present dirty accessed shared
0xc0570000-0xc059ffff         192K  rw  X  present dirty accessed shared
0xc05a0000-0xc7ffffff      125312K  rw     present dirty accessed shared
---[ vmalloc() Area ]---

This patch fixes that.

The implementation is done by reusing the change_page_attr()
function implemented for CONFIG_DEBUG_PAGEALLOC

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 22:55:56 +10:00
Michael Ellerman
5b6c133e08 powerpc/mm/nohash: Move definition of PGALLOC_GFP to fix build errors
In some obscure Book3E configs (randconfig) we can end up missing a
definition for PGALLOC_GFP in pgtable_64.c.

Fix it by moving the definition to asm/pgalloc.h.

Fixes: de3b87611d ("powerpc/mm/book(e)(3s)/64: Add page table accounting")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-15 20:02:56 +10:00
Christophe Leroy
3ee87674e0 powerpc/8xx: Use symbolic PVR value
For the 8xx, PVR values defined in arch/powerpc/include/asm/reg.h
are nowhere used.

Remove all defines and add PVR_8xx

Use it in arch/powerpc/kernel/cputable.c

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 23:32:18 +10:00
Christophe Leroy
968159c003 powerpc/8xx: Getting rid of remaining use of CONFIG_8xx
Two config options exist to define powerpc MPC8xx:
* CONFIG_PPC_8xx
* CONFIG_8xx

arch/powerpc/platforms/Kconfig.cputype has contained the following
comment about CONFIG_8xx item for some years:
"# this is temp to handle compat with arch=ppc"

arch/powerpc is now the only place with remaining use of
CONFIG_8xx: get rid of them.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 23:32:12 +10:00
Christophe Leroy
72e4b2cdf0 powerpc/time: refactor MFTB() to limit number of ifdefs
The 8xx cannot access the TBL and TBU registers using mfspr/mtspr
It must be accessed using mftb/mftbu

Due to this, there is a number of places with #ifdef CONFIG_8xx

This patch defines new macros MFTBL(x) and MFTBU(x) on the same model
as MFTB(x) and tries to make use of them as much as possible.

In arch/powerpc/include/asm/timex.h, we also remove the ifdef
for the asm() operands as the compiler doesn't mind unused operands

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 23:32:09 +10:00
Michael Ellerman
d30a5a5262 powerpc/traps: Use SRR1 defines for program check reasons
Currently we open code the reason codes for program checks. Instead use
the existing SRR1 defines.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 23:31:32 +10:00
Shilpasri G Bhat
bf9571550f powerpc/powernv: Add support to clear sensor groups data
Adds support for clearing different sensor groups. OCC inband sensor
groups like CSM, Profiler, Job Scheduler can be cleared using this
driver. The min/max of all sensors belonging to these sensor groups
will be cleared.

Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 22:40:05 +10:00
Shilpasri G Bhat
8e84b2d1f0 powerpc/powernv: Add support to set power-shifting-ratio
This patch adds support to set power-shifting-ratio which hints the
firmware how to distribute/throttle power between different entities
in a system (e.g CPU v/s GPU). This ratio is used by OCC for power
capping algorithm.

Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 22:40:01 +10:00
Shilpasri G Bhat
cb8b340de2 powerpc/powernv: Add support for powercap framework
Adds a generic powercap framework to change the system powercap
inband through OPAL-OCC command/response interface.

Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 22:39:53 +10:00
Nicholas Piggin
04019bf8eb powerpc: Add irq accounting for watchdog interrupts
This adds an irq counter for the watchdog soft-NMI. This interrupt
only fires when interrupts are soft-disabled, so it will not
increment much even when the watchdog is running. However it's
useful for debugging and sanity checking.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 22:30:02 +10:00
Nicholas Piggin
ca41ad4377 powerpc: Add irq accounting for system reset interrupts
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 22:30:01 +10:00
Andreas Schwab
8a583c0a8d powerpc: Fix invalid use of register expressions
binutils >= 2.26 now warns about misuse of register expressions in
assembler operands that are actually literals, for example:

  arch/powerpc/kernel/entry_64.S:535: Warning: invalid register expression

In practice these are almost all uses of r0 that should just be a
literal 0.

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
[mpe: Mention r0 is almost always the culprit, fold in purgatory change]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 22:29:41 +10:00
Michael Ellerman
21a0e8c14b powerpc/mm/hash64: Make vmalloc 56T on hash
On 64-bit book3s, with the hash MMU, we currently define the kernel
virtual space (vmalloc, ioremap etc.), to be 16T in size. This is a
leftover from pre v3.7 when our user VM was also 16T.

Of that 16T we split it 50/50, with half used for PCI IO and ioremap
and the other 8T for vmalloc.

We never bothered to make it any bigger because 8T of vmalloc ought to
be enough for anybody. But it turns out that's not true, the per cpu
allocator wants large amounts of vmalloc space, not to make large
allocations, but to allow a large stride between allocations, because
we use pcpu_embed_first_chunk().

With a bit of juggling we can increase the entire kernel virtual space
to 64T. The only real complication is the check of the address in the
SLB miss handler, see the comment in the code.

Although we could continue to split virtual space 50/50 as we do now,
no one seems to be running out of PCI IO or ioremap space. So instead
keep that as 8T, and use the remaining 56T for vmalloc.

In future we should be able to increase the kernel virtual space to
512T, the code already supports that, it just needs testing on older
hardware.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2017-08-08 19:37:05 +10:00
Michael Ellerman
63ee9b2ff9 powerpc/mm/book3s64: Make KERN_IO_START a variable
Currently KERN_IO_START is defined as:

 #define KERN_IO_START  (KERN_VIRT_START + (KERN_VIRT_SIZE >> 1))

Although it looks like a constant, both the components are actually
variables, to allow us to have a different value between Radix and
Hash with a single kernel.

However that still requires both Radix and Hash to place the kernel IO
region at the same location relative to the start and end of the
kernel virtual region (namely 1/2 way through it), and we'd like to
change that.

So split KERN_IO_START out into its own variable, and initialise it
for Radix and Hash. In the medium term we should be able to
reconsolidate this, by doing a more involved rearrangement of the
location of the regions.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-08 19:37:04 +10:00
Matt Brown
e66ca3db59 powerpc/powernv: Use darn instruction for get_random_seed() on Power9
This adds powernv_get_random_darn() which utilises the darn instruction,
introduced in ISA v3.0/POWER9.

The darn instruction can potentially return an error, which is supported
by the get_random_seed() API, in normal usage if we see an error we just
return that to the caller.

However when detecting whether darn is functional at boot we try up to
10 times, before deciding that darn doesn't work and failing the
registration of get_random_seed(). That way an intermittent failure
at boot doesn't deprive the system of randomness until the next reboot.

Signed-off-by: Matt Brown <matthew.brown.dev@gmail.com>
[mpe: Move init into a function, tweak change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-08 19:37:03 +10:00
Frederic Barrat
2552910084 powerpc/powernv: Enable PCI peer-to-peer
P9 has support for PCI peer-to-peer, enabling a device to write in the
MMIO space of another device directly, without interrupting the CPU.

This patch adds support for it on powernv, by adding a new API to be
called by drivers. The pnv_pci_set_p2p(...) call configures an
'initiator', i.e the device which will issue the MMIO operation, and a
'target', i.e. the device on the receiving side.

P9 really only supports MMIO stores for the time being but that's
expected to change in the future, so the API allows to define both
load and store operations.

  /* PCI p2p descriptor */
  #define OPAL_PCI_P2P_ENABLE           0x1
  #define OPAL_PCI_P2P_LOAD             0x2
  #define OPAL_PCI_P2P_STORE            0x4

  int pnv_pci_set_p2p(struct pci_dev *initiator, struct pci_dev *target,
                      u64 desc)

It uses a new OPAL call, as the configuration magic is done on the
PHBs by skiboot.

Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: Russell Currey <ruscur@russell.cc>
[mpe: Drop unrelated OPAL calls, s/uint64_t/u64/, minor formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-08 11:27:30 +10:00
Benjamin Herrenschmidt
6ff4d3e966 powerpc: Remove old unused icswx based coprocessor support
We have a whole pile of unused code to maintain the ACOP register,
allocate coprocessor PIDs and handle ACOP faults. This mechanism
was used for the HFI adapter on POWER7 which is dead and gone and
whose driver never went upstream. It was used on some A2 core based
stuff that also never saw the light of day.

Take out all that code.

There is still some POWER8 coprocessor code that uses icswx but it's
kernel only and thus doesn't use any of that infrastructure.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:52 +10:00
Benjamin Herrenschmidt
870cfe77a9 powerpc/mm: Update definitions of DSISR bits
This updates the definitions for the various DSISR bits to
match both some historical stuff and to match new bits on
POWER9.

In addition, we define some masks corresponding to the "bad"
faults on Book3S, and some masks corresponding to the bits
that match between DSISR and SRR1 for a DSI and an ISI.

This comes with a small code update to change the definition
of DSISR_PGDIRFAULT which becomes DSISR_PRTABLE_FAULT to
match architecture 3.0B

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-03 16:06:43 +10:00