drivers/staging/gasket/gasket.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Common Gasket device kernel and user space declarations.
   4  *
   5  * Copyright (C) 2018 Google, Inc.
   6  */
   7 #ifndef __GASKET_H__
   8 #define __GASKET_H__
   9
  10 #include <linux/ioctl.h>
  11 #include <linux/types.h>
  12
  13 /* ioctl structure declarations */
  14
  15 /* Ioctl structures are padded to a multiple of 64 bits */
  16 /* and padded to put 64 bit values on 64 bit boundaries. */
  17 /* Unsigned 64 bit integers are used to hold pointers. */
  18 /* This helps compatibility between 32 and 64 bits. */
  19
  20 /*
  21  * Common structure for ioctls associating an eventfd with a device interrupt,
  22  * when using the Gasket interrupt module.
  23  */
  24 struct gasket_interrupt_eventfd {
  25         u64 interrupt;
  26         u64 event_fd;
  27 };
  28
  29 /*
  30  * Common structure for ioctls mapping and unmapping buffers when using the
  31  * Gasket page_table module.
  32  */
  33 struct gasket_page_table_ioctl {
  34         u64 page_table_index;
  35         u64 size;
  36         u64 host_address;
  37         u64 device_address;
  38 };
  39
  40 /*
  41  * Common structure for ioctls mapping and unmapping buffers when using the
  42  * Gasket page_table module.
  43  * dma_address: phys addr start of coherent memory, allocated by kernel
  44  */
  45 struct gasket_coherent_alloc_config_ioctl {
  46         u64 page_table_index;
  47         u64 enable;
  48         u64 size;
  49         u64 dma_address;
  50 };
  51
  52 /* Base number for all Gasket-common IOCTLs */
  53 #define GASKET_IOCTL_BASE 0xDC
  54
  55 /* Reset the device. */
  56 #define GASKET_IOCTL_RESET _IO(GASKET_IOCTL_BASE, 0)
  57
  58 /* Associate the specified [event]fd with the specified interrupt. */
  59 #define GASKET_IOCTL_SET_EVENTFD                                               \
  60         _IOW(GASKET_IOCTL_BASE, 1, struct gasket_interrupt_eventfd)
  61
  62 /*
  63  * Clears any eventfd associated with the specified interrupt. The (ulong)
  64  * argument is the interrupt number to clear.
  65  */
  66 #define GASKET_IOCTL_CLEAR_EVENTFD _IOW(GASKET_IOCTL_BASE, 2, unsigned long)
  67
  68 /*
  69  * [Loopbacks only] Requests that the loopback device send the specified
  70  * interrupt to the host. The (ulong) argument is the number of the interrupt to
  71  * send.
  72  */
  73 #define GASKET_IOCTL_LOOPBACK_INTERRUPT                                        \
  74         _IOW(GASKET_IOCTL_BASE, 3, unsigned long)
  75
  76 /* Queries the kernel for the number of page tables supported by the device. */
  77 #define GASKET_IOCTL_NUMBER_PAGE_TABLES _IOR(GASKET_IOCTL_BASE, 4, u64)
  78
  79 /*
  80  * Queries the kernel for the maximum size of the page table.  Only the size and
  81  * page_table_index fields are used from the struct gasket_page_table_ioctl.
  82  */
  83 #define GASKET_IOCTL_PAGE_TABLE_SIZE                                           \
  84         _IOWR(GASKET_IOCTL_BASE, 5, struct gasket_page_table_ioctl)
  85
  86 /*
  87  * Queries the kernel for the current simple page table size.  Only the size and
  88  * page_table_index fields are used from the struct gasket_page_table_ioctl.
  89  */
  90 #define GASKET_IOCTL_SIMPLE_PAGE_TABLE_SIZE                                    \
  91         _IOWR(GASKET_IOCTL_BASE, 6, struct gasket_page_table_ioctl)
  92
  93 /*
  94  * Tells the kernel to change the split between the number of simple and
  95  * extended entries in the given page table. Only the size and page_table_index
  96  * fields are used from the struct gasket_page_table_ioctl.
  97  */
  98 #define GASKET_IOCTL_PARTITION_PAGE_TABLE                                      \
  99         _IOW(GASKET_IOCTL_BASE, 7, struct gasket_page_table_ioctl)
 100
 101 /*
 102  * Tells the kernel to map size bytes at host_address to device_address in
 103  * page_table_index page table.
 104  */
 105 #define GASKET_IOCTL_MAP_BUFFER                                                \
 106         _IOW(GASKET_IOCTL_BASE, 8, struct gasket_page_table_ioctl)
 107
 108 /*
 109  * Tells the kernel to unmap size bytes at host_address from device_address in
 110  * page_table_index page table.
 111  */
 112 #define GASKET_IOCTL_UNMAP_BUFFER                                              \
 113         _IOW(GASKET_IOCTL_BASE, 9, struct gasket_page_table_ioctl)
 114
 115 /* Clear the interrupt counts stored for this device. */
 116 #define GASKET_IOCTL_CLEAR_INTERRUPT_COUNTS _IO(GASKET_IOCTL_BASE, 10)
 117
 118 /* Enable/Disable and configure the coherent allocator. */
 119 #define GASKET_IOCTL_CONFIG_COHERENT_ALLOCATOR                                 \
 120         _IOWR(GASKET_IOCTL_BASE, 11, struct gasket_coherent_alloc_config_ioctl)
 121
 122 #endif /* __GASKET_H__ */