1 /* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */ 2 /* 3 * Copyright 2019 Google Inc 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License 7 * as published by the Free Software Foundation; either version 8 * 2 of the License, or (at your option) any later version. 9 * 10 * Provides a simple driver to control the ASPEED P2A interface which allows 11 * the host to read and write to various regions of the BMC's memory. 12 */ 13 14 #ifndef _UAPI_LINUX_ASPEED_P2A_CTRL_H 15 #define _UAPI_LINUX_ASPEED_P2A_CTRL_H 16 17 #include <linux/ioctl.h> 18 #include <linux/types.h> 19 20 #define ASPEED_P2A_CTRL_READ_ONLY 0 21 #define ASPEED_P2A_CTRL_READWRITE 1 22 23 /* 24 * This driver provides a mechanism for enabling or disabling the read-write 25 * property of specific windows into the ASPEED BMC's memory. 26 * 27 * A user can map a region of the BMC's memory as read-only or read-write, with 28 * the caveat that once any region is mapped, all regions are unlocked for 29 * reading. 30 */ 31 32 /* 33 * Unlock a region of BMC physical memory for access from the host. 34 * 35 * Also used to read back the optional memory-region configuration for the 36 * driver. 37 */ 38 struct aspeed_p2a_ctrl_mapping { 39 __u64 addr; 40 __u32 length; 41 __u32 flags; 42 }; 43 44 #define __ASPEED_P2A_CTRL_IOCTL_MAGIC 0xb3 45 46 /* 47 * This IOCTL is meant to configure a region or regions of memory given a 48 * starting address and length to be readable by the host, or 49 * readable-writeable. 50 */ 51 #define ASPEED_P2A_CTRL_IOCTL_SET_WINDOW _IOW(__ASPEED_P2A_CTRL_IOCTL_MAGIC, \ 52 0x00, struct aspeed_p2a_ctrl_mapping) 53 54 /* 55 * This IOCTL is meant to read back to the user the base address and length of 56 * the memory-region specified to the driver for use with mmap. 57 */ 58 #define ASPEED_P2A_CTRL_IOCTL_GET_MEMORY_CONFIG \ 59 _IOWR(__ASPEED_P2A_CTRL_IOCTL_MAGIC, \ 60 0x01, struct aspeed_p2a_ctrl_mapping) 61 62 #endif /* _UAPI_LINUX_ASPEED_P2A_CTRL_H */ 63