Use sizeof(*p) instead of sizeof(struct P) for memory allocation. This
change complies with the Linux kernel coding style. It improves
readability and decreases the opportunity for bugs if the pointer
variable type is changed. Issue found by checkpatch.
Signed-off-by: Kimberly Brown <kimbrownkd@gmail.com>
Acked-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add that number of page table entries and extended address bit offset
are configurable. Update example virtual address format to be more
consistent with typical usage.
Signed-off-by: Nick Ewalt <nicholasewalt@google.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sysfs_show was incorrectly extracting the sysfs_attribute_type from the
gasket_sysfs_attribute. This prevented dispatch from working properly.
Signed-off-by: Nick Ewalt <nicholasewalt@google.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Refactor gasket_components_to_dev_address to be faster and easier to
understand. The old implementation was unnecessarily complex and masked
the page_index for simple addresses but not extended ones. It makes the
most sense for this function to perform no such masking.
Signed-off-by: Nick Ewalt <nicholasewalt@google.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Comments in components_to_dev_address() describing examples are
inconsistent, fix these to be accurate.
Signed-off-by: Nick Ewalt <nicholasewalt@google.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Correctly clean up data structure state in gasket_alloc_coherent_memory
error path, to ensure no double free on the stale pointer value.
Signed-off-by: Nick Ewalt <nicholasewalt@google.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove unnecessary ptes[i].status update in gasket_perform_unmapping.
The vaaue will be cleared in the following memset.
Signed-off-by: Nick Ewalt <nicholasewalt@google.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gasket_alloc_coherent_memory() has some unnecessary code related to out
of memory checking that will never hit the condition checked, remove.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The maximum number of entries in the page table is configurable at
initialization time and should be used in gasket_extended_lvl0_page_idx.
Signed-off-by: Nick Ewalt <nicholasewalt@google.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Previously pages would have never been unmapped in this case.
Signed-off-by: Nick Ewalt <nicholasewalt@google.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Only call dma_unmap_page if there was an associated dma_map_page call.
Signed-off-by: Nick Ewalt <nicholasewalt@google.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The DMA direction supplied to dma_unmap_page should match the
corresponding dma_map_page call, which is mapped bi-directional.
Signed-off-by: Nick Ewalt <nicholasewalt@google.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Extended page tables should be mapped as DMA_TO_DEVICE, not
bi-directional.
Signed-off-by: Nick Ewalt <nicholasewalt@google.com>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Flags should be specified for dma_alloc_coherent() call. Use
GFP_KERNEL, it's fine to sleep here.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Devices not using MSIX don't use the msix_initialized field, so don't
require it to be set in the interrupt system status check. The general
check for interrupts configured that follows can cover both MSIX and
device-managed interrupts.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a brief description and URL for more information on the Apex device,
an Edge TPU (Tensorflow Processing Unit) machine learning accelerator.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The gasket in-kernel framework, recently introduced under staging,
re-implements what is already long-time provided by the UIO
subsystem, with extra PCI BAR remapping and MSI conveniences.
Before moving it out of staging, make sure we add the new bits to
the UIO framework instead, then transform its signle client, the
Apex driver, to a proper UIO driver (uio_driver.h).
Link: https://lkml.kernel.org/r/20180828103817.GB1397@do-kernel
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pass the gasket driver descriptor to the interrupt init function, rather
than exploding out separate parameters from various fields of that
structure. This allows us to make more localized changes to the types
of interrupts supported (MSIX vs. wire, etc.) without affecting the
calling sequence, and seems nicer for simplification purposes.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Split interrupt handler into PCI MSIX-specific and generic functions,
for adding non-MSIX handlers in the future. Move MSIX init code
together,, out of generic init path.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rename lookup_internal_desc() to lookup_pci_internal_desc() to reflect
use for PCI devices only, in prep for non-PCI devices in the future.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Separate code for generic parts of gasket device removal sequence from
the PCI device removal code, in prep for non-PCI devices later.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Split out generic gasket device add code from the code for adding a PCI
gasket device, in prep for other gasket device types in the future.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some explicit memory barriers in the page table code are not necessary,
either because:
(a) The barrier follows a non-relaxed MMIO access that already performs
a read or write memory barrier.
(b) The barrier follows DMA API calls for which the device-visible
effects of IOMMU programming are guaranteed to be flushed to the IOMMU
prior to the call returning, and doesn't need to sync with normal memory
access.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use of readl() is deprecated; readl_relaxed() with appropriate memory
barriers is preferred. Switch to relaxed reads and writes for better
performance as well. Memory barriers required for I/O vs. normal
memory access on Apex devices have already been explicitly coded in the
page table routines.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove debug logs that only indicate the name of the entered function,
in favor of using ftrace for function tracing style logs.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gasket_alloc_dev can retrieve the device name from the parent parameter,
a separate parameter isn't needed for this. Rename the variable to
better reflect its meaning, as the name of the parent device for which a
gasket device is being allocated.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Previous cleanups missed a case of multi-line function call with line
continuation parameters not aligned per kernel style.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A debug log in gasket_alloc_dev() is issued regardless of whether the
device pointer used returned success or error. The log isn't that
useful anyway, remove it.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Reviewed-by: Rob Springer <rspringer@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Array cm_mappable_regions is defined but is never used hence it is
redundant and can be removed.
Cleans up clang warning:
warning: 'cm_mappable_regions' defined but not used [-Wunused-const-variable=]
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove null ptr check before kfree because kfree is null ptr safe.
Issue found by checkpatch.
Signed-off-by: Sumit Kumar <sumit686215@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
That semicolons are unneeded, Just remove them.
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixed a coding style issue related to indentation. Reported by
checkpatch.pl
Signed-off-by: Sumit Pundir <pundirsumit11@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A copy-and-pasted comment from another code sequence is removed from
gasket core init sequence.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The apex device is left out of reset mode at the end of device
probe/initialize processing. Add a call to enter reset at the end of
the sequence, triggering power gating and other low power features.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Keep mutex held across the unregistration operation, until the
driver_desc field of the global table is removed, to prevent a
concurrent accessor from looking up the driver_desc while
gasket_unregister_device() is in the processing of removing it.
Reported-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The gasket framework no longer provides callbacks to the device driver
for sysfs setup and teardown. Move the sysfs setup code to the device
probe function. Apex does not implement sysfs cleanup code.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Gasket device drivers now call into the gasket framework to initialize
and de-initialize, rather than the other way around. The calling code
can perform sysfs setup and cleanup actions without callbacks from the
framework. Remove the sysfs setup and cleanup callbacks.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
