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>
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>
Gasket device drivers are now in charge of orchestrating the device add
and removal sequences, so the callbacks from the framework to the device
drivers for these events are no longer needed.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move gasket device enable/disable functions from internal calls to
external calls from the gasket device drivers. The device driver will
call these functions at appropriate times in its processing, placing
the device driver in control of this sequence and reducing the need for
callbacks from framework back to the device drivers during the
enable/disable sequences.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Device enable/disable operations are moving from being initiated through
the gasket framework to being initiated by the gasket device driver.
The driver can perform any processing needed for these operations before
or after the calls into the framework. Neither of these callbacks are
implemented for the only gasket driver upstream today, apex.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove gasket wrapping of PCI probe, enable, disable, and remove
functions. Replace with calls to add and remove PCI gasket devices,
to be called by the gasket device drivers.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "type of reset" parameter to the gasket device reset APIs isn't
required by the only gasket device submitted upstream, apex.
The framework documents the param as private to the device driver and a
pass-through at the gasket layer, but the gasket core calls the device
driver with a hardcoded reset type of zero, which is not documented as
having a predefined meaning.
In light of all this, remove the reset type parameter from the
framework. Remove the reset ioctl reset type parameter, and bump the
framework version number to reflect the interface change.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Save the struct device pointer to a gasket device in gasket's metadata,
to facilitate use of standard logging calls and in anticipation of
non-PCI gasket devices in the future.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This function is not called anywhere, so just remove it.
Also, as an added benifit, Arnd points out that it doesn't even work
properly:
This code won't work correct during leap seconds or a concurrent
settimeofday() call, and it probably doesn't do what the author intended
even for the normal case, as it passes a timeout in nanoseconds but
reads the time using a jiffies-granularity accessor.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that the SPDX tag is in all gasket files, that identifies the
license in a specific and legally-defined manner. So the extra GPL text
wording can be removed as it is no longer needed at all.
This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.
Cc: Rob Springer <rspringer@google.com>
Cc: John Joseph <jnjoseph@google.com>
Cc: Ben Chan <benchan@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.
Fix up the all of the staging gasket files to have a proper SPDX
identifier, based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.
Cc: Rob Springer <rspringer@google.com>
Cc: John Joseph <jnjoseph@google.com>
Cc: Ben Chan <benchan@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This function only has one caller so mask_width is 1 and mask_shift is
32. Shifting an int by 32 bits is undefined, but I guess on GCC it
wraps to 0x1? Anyway it's supposed to be 0x100000000.
Fixes: 9a69f5087c ("drivers/staging: Gasket driver framework + Apex driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Gasket (Google ASIC Software, Kernel Extensions, and Tools) kernel
framework is a generic, flexible system that supports thin kernel
drivers. Gasket kernel drivers are expected to handle opening and
closing devices, mmap'ing BAR space as requested, a small selection of
ioctls, and handling page table translation (covered below). Any other
functions should be handled by userspace code.
The Gasket common module is not enough to run a device. In order to
customize the Gasket code for a given piece of hardware, a device
specific module must be created. At a minimum, this module must define a
struct gasket_driver_desc containing the device-specific data for use by
the framework; in addition, the module must declare an __init function
that calls gasket_register_device with the module's gasket_driver_desc
struct. Finally, the driver must define an exit function that calls
gasket_unregister_device with the module's gasket_driver_desc struct.
One of the core assumptions of the Gasket framework is that precisely
one process is allowed to have an open write handle to the device node
at any given time. (That process may, once it has one write handle, open
any number of additional write handles.) This is accomplished by
tracking open and close data for each driver instance.
Signed-off-by: Rob Springer <rspringer@google.com>
Signed-off-by: John Joseph <jnjoseph@google.com>
Signed-off-by: Simon Que <sque@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Laurence Rochfort