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alistair23-linux/drivers/staging/gasket/apex.h

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/* SPDX-License-Identifier: GPL-2.0 */
drivers/staging: Gasket driver framework + Apex driver 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>
2018-06-29 20:49:38 -06:00
/*
* Apex kernel-userspace interface definitions.
drivers/staging: Gasket driver framework + Apex driver 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>
2018-06-29 20:49:38 -06:00
*
* Copyright (C) 2018 Google, Inc.
*/
#ifndef __APEX_H__
#define __APEX_H__
#include <linux/ioctl.h>
/* Clock Gating ioctl. */
drivers/staging: Gasket driver framework + Apex driver 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>
2018-06-29 20:49:38 -06:00
struct apex_gate_clock_ioctl {
/* Enter or leave clock gated state. */
u64 enable;
/* If set, enter clock gating state, regardless of custom block's
* internal idle state
*/
u64 force_idle;
};
/* Base number for all Apex-common IOCTLs */
#define APEX_IOCTL_BASE 0x7F
/* Enable/Disable clock gating. */
#define APEX_IOCTL_GATE_CLOCK \
_IOW(APEX_IOCTL_BASE, 0, struct apex_gate_clock_ioctl)
#endif /* __APEX_H__ */