Age | Commit message (Collapse) | Author |
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Enable the drivers on the powerpc arch.
Signed-off-by: Roy Pledge <roy.pledge@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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Add self tests for the DPAA 1.x Queue Manager driver. The tests
ensure that the driver can properly enqueue and dequeue to/from
frame queues using the QMan portal infrastructure.
Signed-off-by: Roy Pledge <roy.pledge@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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Add a self test for the DPAA 1.x Buffer Manager driver. This
test ensures that the driver can properly acquire and release
buffers using the BMan portal infrastructure.
Signed-off-by: Roy Pledge <roy.pledge@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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This driver enables the Freescale DPAA 1.x Queue Manager block.
QMan is a hardware accelerator that manages frame queues. It allows
CPUs and other accelerators connected to the SoC datapath to enqueue
and dequeue ethernet frames, thus providing the infrastructure for
data exchange among CPUs and datapath accelerators.
Signed-off-by: Roy Pledge <roy.pledge@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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This driver enables the Freescale DPAA 1.x Buffer Manager block.
BMan is a hardware accelerator that manages buffer pools. It allows
CPUs and other accelerators connected to the SoC datapath to acquire
and release buffers during data processing.
Signed-off-by: Roy Pledge <roy.pledge@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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User space DTLB miss represent approximatly 90% of TLB misses
so make it the shortest path.
Also remove an unneccessary double jump in FixupDAR
Before this patch, we spend 3.3 TB ticks in the handler for each
user address miss and 3.4 TB ticks for each kernel address miss
After this patch, we send 3.0 TB ticks in the handler for each
user address miss and 3.9 TB ticks for each kernel address miss
Taking into account that user misses represent 90% of the total,
this patch provides an improvement of approx. 9%
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
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When all options are activated, there is not enough space for the
DTLBMiss handlers that handles IMMR area and linear RAM pages in
the exception area once we have added hugepage handling.
So lets move them after .0x2000
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
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Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
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of_mm_gpiochip_add_data() calls mm_gc->save_regs() before
setting the data. Therefore ->save_regs() cannot use
gpiochip_get_data()
An Oops is encountered without this fix.
fixes: 1e714e54b5ca5 ("powerpc: qe_lib-gpio: use gpiochip data pointer")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: <stable@vger.kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Scott Wood <oss@buserror.net>
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During a machine check, the 8xx provides indication of
whether the check is due to data or instruction access, so
let's display it.
Lets also move 8xx specific handling into the new handler.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
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When the watchdog is in NMI mode, the system reset interrupt is
generated when the watchdog counter expires.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
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This allows PCI devices that can only address (e.g.) 36 or 40 bit DMA to
use direct DMA, at the cost of not being able to DMA to non-RAM addresses
(this doesn't affect MSIs as there is a separate dedicated window for
that) which we wouldn't have been able to do anyway if the RAM size didn't
trigger the creation of the second inbound window.
It also fixes an off-by-one error that set dma_direct_ops on PCI devices
whose dma mask could address all the space below the DMA offset
(previously 40 bits), but not the window that starts at the DMA offset.
Signed-off-by: Scott Wood <oss@buserror.net>
Cc: Tillmann Heidsieck <theidsieck@leenox.de>
Tested-by: Tillmann Heidsieck <theidsieck@leenox.de>
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The 8xx has two special registers called EID (External Interrupt
Disable) and EIE (External Interrupt Enable) for clearing/setting
EE in MSR. It avoids the three instructions set mfmsr/ori/mtmsr or
mfmsr/rlwinm/mtmsr and it avoids using a general register.
We just have to write something in the special register to change MSR EE
bit. So we write r0 into the register, regardless of r0 value.
Writing to one of those two special registers also set the MSR RI bit,
but this bit is only unset during beginning of exception prolog and end
of exception epilog. When executing C-functions MSR RI is always set.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
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Factor out the common codes of setup arch functions to a separate
function. It does make no sense to print a board specific info
in setup arch functions, so use a more general one.
For ASP8347E board, there is no pci device node. So it is safe to
invoke mpc83xx_setup_pci() in its setup arch function even there is
no such invocation in its original setup arch function.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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Commit 0e6e01ff694ee ("CPM/QE: use genalloc to manage CPM/QE muram")
has changed the way muram is managed.
genalloc uses kmalloc(), hence requires the SLAB to be up and running.
On powerpc 8xx, cpm_reset() is called early during startup.
cpm_reset() then calls cpm_muram_init() before SLAB is available,
hence the following Oops.
cpm_reset() cannot be called during initcalls because the CPM is
needed for console.
This patch removes the call to cpm_muram_init() from cpm_reset().
cpm_muram_init() will be called from a new function called cpm_init()
which is declared as subsys_initcall, unless cpm_muram_alloc() is
called earlier for the serial console in which case cpm_muram_init()
will be called from there.
The reason for calling it from two places is that some drivers
(e.g. i2c-cpm) need some of the initialisations done by
cpm_muram_init() but don't call cpm_muram_alloc(). The console
driver calls cpm_muram_alloc() but some platforms might not use
the CPM serial ports for console.
[ 0.000000] Unable to handle kernel paging request for data at address 0x00000008
[ 0.000000] Faulting instruction address: 0xc01acce0
[ 0.000000] Oops: Kernel access of bad area, sig: 11 [#1]
[ 0.000000] PREEMPT CMPC885
[ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.4.14-g0886ed8 #5
[ 0.000000] task: c05183e0 ti: c0536000 task.ti: c0536000
[ 0.000000] NIP: c01acce0 LR: c0011068 CTR: 00000000
[ 0.000000] REGS: c0537e50 TRAP: 0300 Not tainted (4.4.14-s3k-dev-g0886ed8-svn)
[ 0.000000] MSR: 00001032 <ME,IR,DR,RI> CR: 28044428 XER: 00000000
[ 0.000000] DAR: 00000008 DSISR: c0000000
GPR00: c0011068 c0537f00 c05183e0 00000000 00009000 ffffffff 00000bc0 ffffffff
GPR08: ff003000 ff00b000 ff003bbf 00000000 22044422 100d43a8 00000000 07ff94e8
GPR16: 00000000 07bb5d70 00000000 07ff81f4 07ff81f4 07ff81f4 00000000 00000000
GPR24: 07ffb3a0 07fe7628 c0550000 c7ffa190 c0540000 ff003bbf 00000000 00000001
[ 0.000000] NIP [c01acce0] gen_pool_add_virt+0x14/0xdc
[ 0.000000] LR [c0011068] cpm_muram_init+0xd4/0x18c
[ 0.000000] Call Trace:
[ 0.000000] [c0537f00] [00000200] 0x200 (unreliable)
[ 0.000000] [c0537f20] [c0011068] cpm_muram_init+0xd4/0x18c
[ 0.000000] [c0537f70] [c0494684] cpm_reset+0xb4/0xc8
[ 0.000000] [c0537f90] [c0494c64] cmpc885_setup_arch+0x10/0x30
[ 0.000000] [c0537fa0] [c0493cd4] setup_arch+0x130/0x168
[ 0.000000] [c0537fb0] [c04906bc] start_kernel+0x88/0x380
[ 0.000000] [c0537ff0] [c0002224] start_here+0x38/0x98
[ 0.000000] Instruction dump:
[ 0.000000] 91430010 91430014 80010014 83e1000c 7c0803a6 38210010 4e800020 7c0802a6
[ 0.000000] 9421ffe0 bf61000c 90010024 7c7e1b78 <80630008> 7c9c2378 7cc31c30 3863001f
[ 0.000000] ---[ end trace dc8fa200cb88537f ]---
fixes: 0e6e01ff694ee ("CPM/QE: use genalloc to manage CPM/QE muram")
Cc: stable@vger.linux.org
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[scottwood: Removed some string changes unrelated to bugfix]
Signed-off-by: Scott Wood <oss@buserror.net>
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Use of_property_read_bool to check for the existence of a property.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression e1,e2;
statement S2,S1;
@@
- if (of_get_property(e1,e2,NULL))
+ if (of_property_read_bool(e1,e2))
S1 else S2
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Scott Wood <oss@buserror.net>
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Use of_property_read_bool to check for the existence of a property.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression e1,e2;
statement S2,S1;
@@
- if (of_get_property(e1,e2,NULL))
+ if (of_property_read_bool(e1,e2))
S1 else S2
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
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Convert fsl_rstcr_restart into a function to be registered with
register_reset_handler().
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
[scottwood: Converted mvme7100 as well]
Signed-off-by: Scott Wood <oss@buserror.net>
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Call out to all restart handlers that were added via
register_restart_handler() API when restarting the machine.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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Factor out a small bit of common code in machine_restart(),
machine_power_off() and machine_halt().
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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Halt callback in struct machdep_calls is declared with __noreturn
attribute, so omitting that attribute in gpio_halt_cb()'s signatrue
results in compilation error.
Change the signature to address the problem as well as change the code
of the function to avoid ever returning from the function.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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Select PHYLIB only if NETDEVICES is enabled and MDIO_BITBANG only if
PHYLIB is present to avoid warnings from Kconfig.
To prevent undefined references during linking register MDIO driver only
if CONFIG_MDIO_BITBANG is enabled.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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PHYLIB depends on NETDEVICES, so to avoid unmet dependencies warning
from Kconfig it needs to be selected conditionally.
Also add checks if PHYLIB is built-in to avoid undefined references to
PHYLIB's symbols.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
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modify get_qe_base function with of_address_to_resource
instead of of_get_property and of_translate_address.
Signed-off-by: Zhao Qiang <qiang.zhao@nxp.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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Use the function resource_size instead of explicit computation.
Problem found using Coccinelle.
Signed-off-by: Vaishali Thakkar <vaishali.thakkar@oracle.com>
Signed-off-by: Scott Wood <oss@buserror.net>
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The same logic appears twice and should probably be pulled out into a
function.
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Rui Teng <rui.teng@linux.vnet.ibm.com>
[mpe: Rename to tm_flush_hash_page() and move comment into the function]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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CLR_TOP32() is defined as blank. Last useful instance of CLR_TOP32()
was removed by commit 40ef8cbc6d360 ("powerpc: Get 64-bit configs to
compile with ARCH=powerpc") in 2005.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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On some CPUs like the 8xx, _PAGE_RW hence _PAGE_WRITE is defined
as 0 and _PAGE_RO has to be set when a page is not writable
_PAGE_RO is defined by default in pte-common.h, however BOOK3S/64
doesn't include that file so _PAGE_RO has to be defined explicitly
in book3s/64/pgtable.h
Fixes: a7b9f671f2d14 ("powerpc32: adds handling of _PAGE_RO")
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>
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In eeh_handle_special_event(), eeh_pe_bus_get() is called before calling
eeh_report_failure() on every device under a PE. If a PE was missing a
bus for some reason, the error would occur before reporting failure, even
though eeh_report_failure() doesn't require a bus.
Fix this by moving the bus retrieval and error check after the
eeh_report_failure() calls.
Signed-off-by: Russell Currey <ruscur@russell.cc>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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When the PE used in pnv_eeh_reset() is that of a VF,
pnv_eeh_reset_vf_pe() is used. Unlike the other reset functions called
in pnv_eeh_reset(), the VF reset doesn't require a bus, and if a bus was
missing the function would error out before resetting the VF PE.
To avoid this, reorder the VF reset function to occur before finding and
checking the bus.
Signed-off-by: Russell Currey <ruscur@russell.cc>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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eeh_pe_bus_get() can return NULL if a PCI bus isn't found for a given PE.
Some callers don't check this, and can cause a null pointer dereference
under certain circumstances.
Fix this by checking NULL everywhere eeh_pe_bus_get() is called.
Fixes: 8a6b1bc70dbb ("powerpc/eeh: EEH core to handle special event")
Cc: stable@vger.kernel.org # v3.11+
Signed-off-by: Russell Currey <ruscur@russell.cc>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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When we originally added the ability to split the exception vectors from
the kernel (commit 1f6a93e4c35e ("powerpc: Make it possible to move the
interrupt handlers away from the kernel" 2008-09-15)), the LOAD_HANDLER() macro
used an addi instruction to compute the offset of the common handler
from the kernel base address.
Using addi meant the handler had to be within 32K of the kernel base
address, due to the addi instruction taking a signed immediate value.
That necessitated creating a trampoline for the system call handler,
because system_call_common (in entry64.S) is not linked within 32K of
the kernel base address.
Later in commit 61e2390ede3c ("powerpc: Make load_hander handle upto 64k
offset" 2012-11-15) we changed LOAD_HANDLER to take a 64K offset, by
changing it to use ori.
Although system_call_common is not in head_64.S or exceptions-64s.S, it
is included in head-y, which causes it to be linked early in the kernel
text, so in practice it ends up below 64K. Additionally if it can't be
placed below 64K the linker will fail to build with a "relocation
truncated to fit" error.
So remove the trampoline.
Newer toolchains are able to work out that the ori in LOAD_HANDLER only
takes a 16 bit offset, and so they generate a 16 bit relocation. Older
toolchains (binutils 2.22 at least) are not so smart, so we have to add
the @l annotation to tell the assembler to generate a 16 bit relocation.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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The 0xf80 hv_facility_unavailable trampoline branches to the 0xf60
handler. This works because they both do the same thing, but it should
be fixed.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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On EEH events the kernel will print a dump of relevant registers.
If EEH is unavailable (i.e. CONFIG_EEH is disabled, a new platform
doesn't have EEH support, etc) this information isn't readily available.
Add a new debugfs handler to trigger a PHB register dump, so that this
information can be made available on demand.
Signed-off-by: Russell Currey <ruscur@russell.cc>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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The only difference is now the TCE table check which doesn't need
to be ifdef'ed out, it will basically do nothing on BookE (it is
only useful for ancient IBM machines).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Currently we turn the MMU off after copying the image, and we make
sure there is no overlap between the hash table and the target pages
in that case.
That doesn't work for Radix however. In that case, the page tables
are scattered and we can't really enforce that the target of the
image isn't overlapping one of them.
So instead, let's turn the MMU off before copying the image in radix
mode. Thankfully, in radix mode, even under a hypervisor, we know we
don't have the same kind of RMA limitations that hash mode has.
While at it, also turn the MMU off early when using hash in non-LPAR
mode, that way we can get rid of the collision check completely.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-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>
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Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Just using the hash ops won't work anymore since radix will have
NULL in there. Instead create an mmu_cleanup_all() function which
will do the right thing based on the MMU mode.
For Radix, for now I clear UPRT and the PTCR, effectively switching
back to Radix with no partition table setup.
Currently set it to NULL on BookE thought it might be a good idea
to wipe the TLB there (Scott ?)
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-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>
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With Radix, it can be NULL even on !BOOKE these days so replace
the ifdef with a NULL check which is cleaner anyway.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-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>
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NO_IRQ has been == 0 on powerpc for just over ten years (since commit
0ebfff1491ef ("[POWERPC] Add new interrupt mapping core and change
platforms to use it")). It's also 0 on most other arches.
Although it's fairly harmless, every now and then it causes confusion
when a driver is built on powerpc and another arch which doesn't define
NO_IRQ. There's at least 6 definitions of NO_IRQ in drivers/, at least
some of which are to work around that problem.
So we'd like to remove it. This is fairly trivial in the arch code, we
just convert:
if (irq == NO_IRQ) to if (!irq)
if (irq != NO_IRQ) to if (irq)
irq = NO_IRQ; to irq = 0;
return NO_IRQ; to return 0;
And a few other odd cases as well.
At least for now we keep the #define NO_IRQ, because there is driver
code that uses NO_IRQ and the fixes to remove those will go via other
trees.
Note we also change some occurrences in PPC sound drivers, drivers/ps3,
and drivers/macintosh.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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Fred has taken over the cxl maintenance I was doing. This updates the
MAINTAINERS file to reflect this.
It also removes a duplicate entry in the files covered and adds an entry
for the CXL PCI code in arch/powerpc.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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If we fail to allocate work, we don't end up using hp_errlog_copy. Free it
in the error path.
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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When we merge two contiguous partitions whose signatures are marked
NVRAM_SIG_FREE, We need update prev's length and checksum, then write it
to nvram, not cur's. So lets fix this mistake now.
Also use memset instead of strncpy to set the partition's name. It's
more readable if we want to fill up with duplicate chars .
Fixes: fa2b4e54d41f ("powerpc/nvram: Improve partition removal")
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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If kmemdup fails, We need kfree *buff* first then return -ENOMEM.
Otherwise there is a memory leak.
Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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mtmsrd with L=1 only affects MSR_EE and MSR_RI bits, and we always
know what state those bits are, so the kernel MSR does not need to be
loaded when modifying them.
mtmsrd is often in the critical execution path, so avoiding dependency
on even L1 load is noticable. On a POWER8 this saves about 3 cycles
from the syscall path, and possibly a few from other exception returns
(not measured).
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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The mflr r10 instruction was left over from when the code used LR to
branch to system_call_entry from the exception handler. That was
changed by commit 6a404806dfce ("powerpc: Avoid link stack corruption in
MMU on syscall entry path") to use the count register. The value is
never used now, so mflr can be removed, and r10 can be used for storage
rather than spilling to the SPR scratch register.
The scratch register spill causes a long pipeline stall due to the SPR
read after write. This change brings getppid syscall cost from 406 to
376 cycles on POWER8. getppid for non-relocatable case is 371 cycles.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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For hugetlb to work with 4K page size, we need MAX_ORDER to be 13 or
more. When switching from a 64K page size to 4K linux page size using
make oldconfig, we end up with a CONFIG_FORCE_MAX_ZONEORDER value of 9.
This results in a 16M hugepage beiing considered as a gigantic huge page
which in turn results in failure to setup hugepages if gigantic hugepage
support is not enabled.
This also results in kernel crash with 4K radix configuration. We
hit the below BUG_ON on radix:
kernel BUG at mm/huge_memory.c:364!
Oops: Exception in kernel mode, sig: 5 [#1]
SMP NR_CPUS=2048 NUMA PowerNV
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.8.0-rc1-00006-gbae9cc6 #1
task: c0000000f1af8000 task.stack: c0000000f1aec000
NIP: c000000000c5fa0c LR: c000000000c5f9d8 CTR: c000000000c5f9a4
REGS: c0000000f1aef920 TRAP: 0700 Not tainted (4.8.0-rc1-00006-gbae9cc6)
MSR: 9000000102029033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE,TM[E]> CR: 24000844 XER: 00000000
CFAR: c000000000c5f9e0 SOFTE: 1
....
NIP [c000000000c5fa0c] hugepage_init+0x68/0x238
LR [c000000000c5f9d8] hugepage_init+0x34/0x238
Fixes: a7ee539584acf ("powerpc/Kconfig: Update config option based on page size")
Cc: stable@vger.kernel.org # v4.7+
Reported-by: Santhosh <santhog4@linux.vnet.ibm.com>
Signed-off-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>
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Add some documentation for the 64-bit syscall ABI, which doesn't seem
to be documented elsewhere.
This attempts to document existing practice. The only small discrepancy
is glibc clobbers not quite matching the kernel (e.g., xer, some
vsyscalls trash cr1 whereas glibc only clobbers cr0). These will be
resolved after this document is merged.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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