24 Aug, 2020
1 commit
-
Existing users of ocxl_link_irq_alloc() have been converted to obtain
the trigger page of an interrupt through xive directly, we therefore
have no need to return the trigger page when allocating an interrupt.It also allows ocxl to use the xive native interface to allocate
interrupts, instead of its custom service.Signed-off-by: Frederic Barrat
Reviewed-by: Cédric Le Goater
Reviewed-by: Greg Kurz
Acked-by: Andrew Donnellan
Signed-off-by: Michael Ellerman
Link: https://lore.kernel.org/r/20200403153838.29224-4-fbarrat@linux.ibm.com
29 Jul, 2020
2 commits
-
This patch addresses warnings and errors from the kernel doc scripts for
the OpenCAPI driver.It also makes minor tweaks to make the docs more consistent.
Signed-off-by: Alastair D'Silva
Acked-by: Andrew Donnellan
Signed-off-by: Michael Ellerman
Link: https://lore.kernel.org/r/20200415012343.919255-3-alastair@d-silva.org -
Function declarations don't need externs, remove the existing ones
so they are consistent with newer codeSigned-off-by: Alastair D'Silva
Acked-by: Andrew Donnellan
Acked-by: Frederic Barrat
Signed-off-by: Michael Ellerman
Link: https://lore.kernel.org/r/20200415012343.919255-2-alastair@d-silva.org
15 Jul, 2020
1 commit
-
Some opencapi FPGA images allow to control if the FPGA should be reloaded
on the next adapter reset. If it is supported, the image specifies it
through a Vendor Specific DVSEC in the config space of function 0.Signed-off-by: Philippe Bergheaud
Signed-off-by: Frederic Barrat
Reviewed-by: Andrew Donnellan
Signed-off-by: Michael Ellerman
Link: https://lore.kernel.org/r/20200619140439.153962-1-fbarrat@linux.ibm.com
09 Aug, 2019
1 commit
-
This header is included in drivers/auxdisplay/. Make it a local header.
Reviewed-by: Geert Uytterhoeven
Signed-off-by: Masahiro Yamada
Signed-off-by: Miguel Ojeda
14 Jul, 2019
1 commit
-
Pull powerpc updates from Michael Ellerman:
"Notable changes:- Removal of the NPU DMA code, used by the out-of-tree Nvidia driver,
as well as some other functions only used by drivers that haven't
(yet?) made it upstream.- A fix for a bug in our handling of hardware watchpoints (eg. perf
record -e mem: ...) which could lead to register corruption and
kernel crashes.- Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for
vmalloc when using the Radix MMU.- A large but incremental rewrite of our exception handling code to
use gas macros rather than multiple levels of nested CPP macros.And the usual small fixes, cleanups and improvements.
Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab,
Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann,
Athira Rajeev, Cédric Le Goater, Christian Lamparter, Christophe
Leroy, Christophe Lombard, Christoph Hellwig, Daniel Axtens, Denis
Efremov, Enrico Weigelt, Frederic Barrat, Gautham R. Shenoy, Geert
Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg Kurz,
Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro
Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N.
Rao, Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi
Bangoria, Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher
Boessenkool, Shaokun Zhang, Shawn Anastasio, Stewart Smith, Suraj
Jitindar Singh, Thiago Jung Bauermann, YueHaibing"* tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (163 commits)
powerpc/powernv/idle: Fix restore of SPRN_LDBAR for POWER9 stop state.
powerpc/eeh: Handle hugepages in ioremap space
ocxl: Update for AFU descriptor template version 1.1
powerpc/boot: pass CONFIG options in a simpler and more robust way
powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h
powerpc/irq: Don't WARN continuously in arch_local_irq_restore()
powerpc/module64: Use symbolic instructions names.
powerpc/module32: Use symbolic instructions names.
powerpc: Move PPC_HA() PPC_HI() and PPC_LO() to ppc-opcode.h
powerpc/module64: Fix comment in R_PPC64_ENTRY handling
powerpc/boot: Add lzo support for uImage
powerpc/boot: Add lzma support for uImage
powerpc/boot: don't force gzipped uImage
powerpc/8xx: Add microcode patch to move SMC parameter RAM.
powerpc/8xx: Use IO accessors in microcode programming.
powerpc/8xx: replace #ifdefs by IS_ENABLED() in microcode.c
powerpc/8xx: refactor programming of microcode CPM params.
powerpc/8xx: refactor printing of microcode patch name.
powerpc/8xx: Refactor microcode write
powerpc/8xx: refactor writing of CPM microcode arrays
...
10 Jul, 2019
1 commit
-
The OpenCAPI discovery and configuration specification has been
updated and introduces version 1.1 of the AFU descriptor template,
with new fields to better define the memory layout of an OpenCAPI
adapter.The ocxl driver doesn't do much yet to support LPC memory but as we
start seeing (non-LPC) AFU images using the new template, this patch
updates the config space parsing code to avoid spitting a warning.Signed-off-by: Alastair D'Silva
Signed-off-by: Frederic Barrat
Reviewed-by: Christophe Lombard
Acked-by: Andrew Donnellan
Signed-off-by: Michael Ellerman
Link: https://lore.kernel.org/r/20190605111545.19762-1-fbarrat@linux.ibm.com
31 May, 2019
1 commit
-
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later versionextracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: Thomas Gleixner
Reviewed-by: Allison Randal
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman
24 May, 2019
1 commit
-
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
675 mass ave cambridge ma 02139 usaextracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 441 file(s).
Signed-off-by: Thomas Gleixner
Reviewed-by: Michael Ellerman (powerpc)
Reviewed-by: Richard Fontana
Reviewed-by: Allison Randal
Reviewed-by: Kate Stewart
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520071858.739733335@linutronix.de
Signed-off-by: Greg Kroah-Hartman
03 May, 2019
6 commits
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External drivers that communicate via OpenCAPI will need to make
MMIO calls to interact with the devices.Signed-off-by: Alastair D'Silva
Reviewed-by: Greg Kurz
Acked-by: Frederic Barrat
Signed-off-by: Michael Ellerman -
Event_fd is only used in the driver frontend, so it does not
need to exist in the backend code. Relocate it to the frontend
and provide an opaque mechanism for consumers instead.Signed-off-by: Alastair D'Silva
Acked-by: Frederic Barrat
Signed-off-by: Michael Ellerman -
Most OpenCAPI operations require a valid context, so
exposing these functions to external drivers is necessary.Signed-off-by: Alastair D'Silva
Reviewed-by: Greg Kurz
Acked-by: Frederic Barrat
Signed-off-by: Michael Ellerman -
The OCXL driver contains both frontend code for interacting with userspace,
as well as backend code for interacting with the hardware.This patch separates the backend code from the frontend so that it can be
used by other device drivers that communicate via OpenCAPI.Relocate dev, cdev & sysfs files to the frontend code to allow external
drivers to maintain their own devices.Reference counting on the device in the backend is replaced with kref
counting.Move file & sysfs layer initialisation from core.c (backend) to
pci.c (frontend).Create an ocxl_function oriented interface for initing devices &
enumerating AFUs.Signed-off-by: Alastair D'Silva
Acked-by: Frederic Barrat
Signed-off-by: Michael Ellerman -
Remove some unused exported symbols.
Signed-off-by: Alastair D'Silva
Reviewed-by: Greg Kurz
Acked-by: Frederic Barrat
Acked-by: Andrew Donnellan
Signed-off-by: Michael Ellerman -
The 'extern' keyword adds no value here.
Signed-off-by: Alastair D'Silva
Reviewed-by: Greg Kurz
Acked-by: Frederic Barrat
Acked-by: Andrew Donnellan
Signed-off-by: Michael Ellerman
17 Mar, 2019
1 commit
-
The charlcd_free() is a counterpart to charlcd_alloc()
and should be called symmetrically on tear down.Reviewed-by: Geert Uytterhoeven
Signed-off-by: Andy Shevchenko
Signed-off-by: Miguel Ojeda
02 Jul, 2018
6 commits
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Remove abandonned capi support for the Mellanox CX4.
This reverts commit a19bd79e31769626d288cc016e21a31b6f47bf6f.
Signed-off-by: Frederic Barrat
Acked-by: Andrew Donnellan
Signed-off-by: Michael Ellerman -
Remove abandonned capi support for the Mellanox CX4.
This reverts commit 4e56f858bdde5cbfb70f61baddfaa56a8ed851bf.
Signed-off-by: Frederic Barrat
Acked-by: Andrew Donnellan
Signed-off-by: Michael Ellerman -
Remove abandonned capi support for the Mellanox CX4.
This reverts commit b0b5e5918ad1babfd1d43d98c7281926a7b57b9f.
Signed-off-by: Alastair D'Silva
Acked-by: Andrew Donnellan
Signed-off-by: Michael Ellerman -
Remove abandonned capi support for the Mellanox CX4.
This reverts commit cbce0917e2e47d4bf5aa3b5fd6b1247f33e1a126.
Signed-off-by: Alastair D'Silva
Acked-by: Andrew Donnellan
Signed-off-by: Michael Ellerman -
Remove abandonned capi support for the Mellanox CX4.
This reverts commit a2f67d5ee8d950caaa7a6144cf0bfb256500b73e.
Signed-off-by: Alastair D'Silva
Acked-by: Andrew Donnellan
Signed-off-by: Michael Ellerman -
Remove abandonned capi support for the Mellanox CX4.
The symbol 'cxl_set_translation_mode' is never called, so
ctx->real_mode is always false.This reverts commit 7a0d85d313c2066712e530e668bc02bb741a685c.
Signed-off-by: Alastair D'Silva
Acked-by: Andrew Donnellan
Signed-off-by: Michael Ellerman
03 Jun, 2018
1 commit
-
In order to successfully issue as_notify, an AFU needs to know the TID
to notify, which in turn means that this information should be
available in userspace so it can be communicated to the AFU.Signed-off-by: Alastair D'Silva
Acked-by: Andrew Donnellan
Signed-off-by: Michael Ellerman
03 Feb, 2018
1 commit
-
Pull powerpc updates from Michael Ellerman:
"Highlights:- Enable support for memory protection keys aka "pkeys" on Power7/8/9
when using the hash table MMU.- Extend our interrupt soft masking to support masking PMU interrupts
as well as "normal" interrupts, and then use that to implement
local_t for a ~4x speedup vs the current atomics-based
implementation.- A new driver "ocxl" for "Open Coherent Accelerator Processor
Interface (OpenCAPI)" devices.- Support for new device tree properties on PowerVM to describe
hotpluggable memory and devices.- Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 64-bit
VDSO.- Freescale updates from Scott: fixes for CPM GPIO and an FSL PCI
erratum workaround, plus a minor cleanup patch.As well as quite a lot of other changes all over the place, and small
fixes and cleanups as always.Thanks to: Alan Modra, Alastair D'Silva, Alexey Kardashevskiy,
Alistair Popple, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V,
Anju T Sudhakar, Anshuman Khandual, Anton Blanchard, Arnd Bergmann,
Balbir Singh, Benjamin Herrenschmidt, Bhaktipriya Shridhar, Bryant G.
Ly, Cédric Le Goater, Christophe Leroy, Christophe Lombard, Cyril Bur,
David Gibson, Desnes A. Nunes do Rosario, Dmitry Torokhov, Frederic
Barrat, Geert Uytterhoeven, Guilherme G. Piccoli, Gustavo A. R. Silva,
Gustavo Romero, Ivan Mikhaylov, Joakim Tjernlund, Joe Perches, Josh
Poimboeuf, Juan J. Alvarez, Julia Cartwright, Kamalesh Babulal,
Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre, Michael
Bringmann, Michael Hanselmann, Michael Neuling, Nathan Fontenot,
Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Philippe Bergheaud,
Ram Pai, Russell Currey, Santosh Sivaraj, Scott Wood, Seth Forshee,
Simon Guo, Stewart Smith, Sukadev Bhattiprolu, Thiago Jung Bauermann,
Vaibhav Jain, Vasyl Gomonovych"* tag 'powerpc-4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (199 commits)
powerpc/mm/radix: Fix build error when RADIX_MMU=n
macintosh/ams-input: Use true and false for boolean values
macintosh: change some data types from int to bool
powerpc/watchdog: Print the NIP in soft_nmi_interrupt()
powerpc/watchdog: regs can't be null in soft_nmi_interrupt()
powerpc/watchdog: Tweak watchdog printks
powerpc/cell: Remove axonram driver
rtc-opal: Fix handling of firmware error codes, prevent busy loops
powerpc/mpc52xx_gpt: make use of raw_spinlock variants
macintosh/adb: Properly mark continued kernel messages
powerpc/pseries: Fix cpu hotplug crash with memoryless nodes
powerpc/numa: Ensure nodes initialized for hotplug
powerpc/numa: Use ibm,max-associativity-domains to discover possible nodes
powerpc/kernel: Block interrupts when updating TIDR
powerpc/powernv/idoa: Remove unnecessary pcidev from pci_dn
powerpc/mm/nohash: do not flush the entire mm when range is a single page
powerpc/pseries: Add Initialization of VF Bars
powerpc/pseries/pci: Associate PEs to VFs in configure SR-IOV
powerpc/eeh: Add EEH notify resume sysfs
powerpc/eeh: Add EEH operations to notify resume
...
24 Jan, 2018
2 commits
-
Some of the functions done by the generic driver should also be needed
by other opencapi drivers: attaching a context to an adapter,
translation fault handling, AFU interrupt allocation...So to avoid code duplication, the driver provides a kernel API that
other drivers can use, similar to calling a in-kernel library.It is still a bit theoretical, for lack of real hardware, and will
likely need adjustements down the road. But we used the cxlflash
driver as a guinea pig.Signed-off-by: Frederic Barrat
Signed-off-by: Michael Ellerman -
In the opencapi protocol, host memory contexts are referenced by a
'actag'. During setup, a driver must tell the device how many actags
it can used, and what values are acceptable.On POWER9, the NPU can handle 64 actags per link, so they must be
shared between all the PCI functions of the link. To get a global
picture of how many actags are used by each AFU of every function, we
capture some data at the end of PCI enumeration, so that actags can be
shared fairly if needed.This is not powernv specific per say, but rather a consequence of the
opencapi configuration specification being quite general. The number
of available actags on POWER9 makes it more likely to be hit. This is
somewhat mitigated by the fact that existing AFUs are coded by
requesting a reasonable count of actags and existing devices carry
only one AFU.Signed-off-by: Frederic Barrat
Signed-off-by: Michael Ellerman
29 Nov, 2017
1 commit
-
Signed-off-by: Al Viro
03 Jul, 2017
1 commit
-
This patch exports a in-kernel 'library' API which can be called by
other drivers to help interacting with an IBM XSL on a POWER9 system.The XSL (Translation Service Layer) is a stripped down version of the
PSL (Power Service Layer) used in some cards such as the Mellanox CX5.
Like the PSL, it implements the CAIA architecture, but has a number
of differences, mostly in it's implementation dependent registers.The XSL also uses a special DMA cxl mode, which uses a slightly
different init sequence for the CAPP and PHB.Signed-off-by: Andrew Donnellan
Signed-off-by: Christophe Lombard
Acked-by: Frederic Barrat
Signed-off-by: Michael Ellerman
17 Mar, 2017
2 commits
-
In 4-bit mode, 8-bit commands and data are written using two raw writes
to the data interface: high nibble first, low nibble last. This must be
handled by the low-level driver.However, as we don't know in which mode (4-bit or 8-bit) nor 4-bit phase
the LCD was left, initialization must always be handled using raw
writes, and needs to configure the LCD for 8-bit mode first.Signed-off-by: Geert Uytterhoeven
Signed-off-by: Greg Kroah-Hartman -
Extract the character LCD core from the Parallel port LCD/Keypad Panel
driver in the misc subsystem, and convert it into a subdriver in the
auxdisplay subsystem. This allows the character LCD core to be used by
other drivers later.Compilation is controlled by its own Kconfig symbol CHARLCD, which is to
be selected by its users, but can be enabled manually for
compile-testing.All functions changed their prefix from "lcd_" to "charlcd_", and gained
a "struct charlcd *" parameter to operate on a specific instance.
While the driver API thus is ready to support multiple instances, the
current limitation of a single display (/dev/lcd has a single misc minor
assigned) is retained.No functional changes intended.
Signed-off-by: Geert Uytterhoeven
Signed-off-by: Greg Kroah-Hartman
14 Jul, 2016
7 commits
-
Add a new API, cxl_check_and_switch_mode() to allow for switching of
bi-modal CAPI cards, such as the Mellanox CX-4 network card.When a driver requests to switch a card to CAPI mode, use PCI hotplug
infrastructure to remove all PCI devices underneath the slot. We then write
an updated mode control register to the CAPI VSEC, hot reset the card, and
reprobe the card.As the card may present a different set of PCI devices after the mode
switch, use the infrastructure provided by the pnv_php driver and the OPAL
PCI slot management facilities to ensure that:* the old devices are removed from both the OPAL and Linux device trees
* the new devices are probed by OPAL and added to the OPAL device tree
* the new devices are added to the Linux device tree and probed through
the regular PCI device probe pathAs such, introduce a new option, CONFIG_CXL_BIMODAL, with a dependency on
the pnv_php driver.Refactor existing code that touches the mode control register in the
regular single mode case into a new function, setup_cxl_protocol_area().Co-authored-by: Ian Munsie
Cc: Gavin Shan
Signed-off-by: Andrew Donnellan
Signed-off-by: Ian Munsie
Reviewed-by: Gavin Shan
Signed-off-by: Michael Ellerman -
The Mellanox CX4 in cxl mode uses a hybrid interrupt model, where
interrupts are routed from the networking hardware to the XSL using the
MSIX table, and from there will be transformed back into an MSIX
interrupt using the cxl style interrupts (i.e. using IVTE entries and
ranges to map a PE and AFU interrupt number to an MSIX address).We want to hide the implementation details of cxl interrupts as much as
possible. To this end, we use a special version of the MSI setup &
teardown routines in the PHB while in cxl mode to allocate the cxl
interrupts and configure the IVTE entries in the process element.This function does not configure the MSIX table - the CX4 card uses a
custom format in that table and it would not be appropriate to fill that
out in generic code. The rest of the functionality is similar to the
"Full MSI-X mode" described in the CAIA, and this could be easily
extended to support other adapters that use that mode in the future.The interrupts will be associated with the default context. If the
maximum number of interrupts per context has been limited (e.g. by the
mlx5 driver), it will automatically allocate additional kernel contexts
to associate extra interrupts as required. These contexts will be
started using the same WED that was used to start the default context.Signed-off-by: Ian Munsie
Reviewed-by: Andrew Donnellan
Signed-off-by: Michael Ellerman -
The Mellanox CX4 has a hardware limitation where only 4 bits of the
AFU interrupt number can be passed to the XSL when sending an interrupt,
limiting it to only 15 interrupts per context (AFU interrupt number 0 is
invalid).In order to overcome this, we will allocate additional contexts linked
to the default context as extra address space for the extra interrupts -
this will be implemented in the next patch.This patch adds the preliminary support to allow this, by way of adding
a linked list in the context structure that we use to keep track of the
contexts dedicated to interrupts, and an API to simultaneously iterate
over the related context structures, AFU interrupt numbers and hardware
interrupt numbers. The point of using a single API to iterate these is
to hide some of the details of the iteration from external code, and to
reduce the number of APIs that need to be exported via base.c to allow
built in code to call.Signed-off-by: Ian Munsie
Reviewed-by: Frederic Barrat
Reviewed-by: Andrew Donnellan
Signed-off-by: Michael Ellerman -
These APIs will be used by the Mellanox CX4 support. While they function
standalone to configure existing behaviour, their primary purpose is to
allow the Mellanox driver to inform the cxl driver of a hardware
limitation, which will be used in a future patch.Signed-off-by: Ian Munsie
Reviewed-by: Frederic Barrat
Reviewed-by: Andrew Donnellan
Signed-off-by: Michael Ellerman -
The cxl kernel API has a concept of a default context associated with
each PCI device under the virtual PHB. The Mellanox CX4 will also use
the cxl kernel API, but it does not use a virtual PHB - rather, the AFU
appears as a physical function as a peer to the networking functions.In order to allow the kernel API to work with those networking
functions, we will need to associate a default context with them as
well. To this end, refactor the corresponding code to do this in vphb.c
and export it so that it can be called from the PHB code.Signed-off-by: Ian Munsie
Reviewed-by: Frederic Barrat
Reviewed-by: Andrew Donnellan
Signed-off-by: Michael Ellerman -
The Mellanox CX4 uses a model where the AFU is one physical function of
the device, and is used by other peer physical functions of the same
device. This will require those other devices to grab a reference on the
AFU when they are initialised to make sure that it does not go away
during their lifetime.Move the AFU refcount functions to base.c so they can be called from
the PHB code.Signed-off-by: Ian Munsie
Reviewed-by: Andrew Donnellan
Reviewed-by: Frederic Barrat
Signed-off-by: Michael Ellerman -
This extends the check that the adapter is in a CAPI capable slot so
that it may be called by external users in the kernel API. This will be
used by the upcoming Mellanox CX4 support, which needs to know ahead of
time if the card can be switched to cxl mode so that it can leave it in
PCI mode if it is not.This API takes a parameter to check if CAPP DMA mode is supported, which
it currently only allows on P8NVL systems, since that mode currently has
issues accessing memory < 4GB on P8, and we cannot realistically avoid
that.This API does not currently check if a CAPP unit is available (i.e. not
already assigned to another PHB) on P8. Doing so would be racy since it
is assigned on a first come first serve basis, and so long as CAPP DMA
mode is not supported on P8 we don't need this, since the only
anticipated user of this API requires CAPP DMA mode.Cc: Philippe Bergheaud
Signed-off-by: Ian Munsie
Reviewed-by: Andrew Donnellan
Reviewed-by: Frederic Barrat
Signed-off-by: Michael Ellerman
28 Jun, 2016
2 commits
-
This provides AFU drivers a means to associate private data with a cxl
context. This is particularly intended for make the new callbacks for
driver specific events easier for AFU drivers to use, as they can easily
get back to any private data structures they may use.Signed-off-by: Michael Neuling
Signed-off-by: Ian Munsie
Signed-off-by: Philippe Bergheaud
Reviewed-by: Andrew Donnellan
Signed-off-by: Michael Ellerman -
This adds an afu_driver_ops structure with fetch_event() and
event_delivered() callbacks. An AFU driver such as cxlflash can fill
this out and associate it with a context to enable passing custom AFU
specific events to userspace.This also adds a new kernel API function cxl_context_pending_events(),
that the AFU driver can use to notify the cxl driver that new specific
events are ready to be delivered, and wake up anyone waiting on the
context wait queue.The current count of AFU driver specific events is stored in the field
afu_driver_events of the context structure.The cxl driver checks the afu_driver_events count during poll, select,
read, etc. calls to check if an AFU driver specific event is pending,
and calls fetch_event() to obtain and deliver that event. This way, the
cxl driver takes care of all the usual locking semantics around these
calls and handles all the generic cxl events, so that the AFU driver
only needs to worry about it's own events.fetch_event() return a struct cxl_event_afu_driver_reserved, allocated
by the AFU driver, and filled in with the specific event information and
size. Total event size (header + data) should not be greater than
CXL_READ_MIN_SIZE (4K).Th cxl driver prepends an appropriate cxl event header, copies the event
to userspace, and finally calls event_delivered() to return the status of
the operation to the AFU driver. The event is identified by the context
and cxl_event_afu_driver_reserved pointers.Since AFU drivers provide their own means for userspace to obtain the
AFU file descriptor (i.e. cxlflash uses an ioctl on their scsi file
descriptor to obtain the AFU file descriptor) and the generic cxl driver
will never use this event, the ABI of the event is up to each individual
AFU driver.Signed-off-by: Philippe Bergheaud
Signed-off-by: Michael Ellerman
11 May, 2016
1 commit
-
cxl devices typically access memory using an MMU in much the same way as
the CPU, and each context includes a state register much like the MSR in
the CPU. Like the CPU, the state register includes a bit to enable
relocation, which we currently always enable.In some cases, it may be desirable to allow a device to access memory
using real addresses instead of effective addresses, so this adds a new
API, cxl_set_translation_mode, that can be used to disable relocation
on a given kernel context. This can allow for the creation of a special
privileged context that the device can use if it needs relocation
disabled, and can use regular contexts at times when it needs relocation
enabled.This interface is only available to users of the kernel API for obvious
reasons, and will never be supported in a virtualised environment.This will be used by the upcoming cxl support in the mlx5 driver.
Signed-off-by: Ian Munsie
Signed-off-by: Michael Ellerman