/* * Memory transaction attributes * * Copyright (c) 2015 Linaro Limited. * * Authors: * Peter Maydell * * This work is licensed under the terms of the GNU GPL, version 2 or later. * See the COPYING file in the top-level directory. * */ #ifndef MEMATTRS_H #define MEMATTRS_H /* Every memory transaction has associated with it a set of * attributes. Some of these are generic (such as the ID of * the bus master); some are specific to a particular kind of * bus (such as the ARM Secure/NonSecure bit). We define them * all as non-overlapping bitfields in a single struct to avoid * confusion if different parts of QEMU used the same bit for * different semantics. */ typedef struct MemTxAttrs { /* Bus masters which don't specify any attributes will get this * (via the MEMTXATTRS_UNSPECIFIED constant), so that we can * distinguish "all attributes deliberately clear" from * "didn't specify" if necessary. */ unsigned int unspecified:1; /* ARM/AMBA: TrustZone Secure access * x86: System Management Mode access */ unsigned int secure:1; /* Memory access is usermode (unprivileged) */ unsigned int user:1; /* Requester ID (for MSI for example) */ unsigned int requester_id:16; } MemTxAttrs; /* Bus masters which don't specify any attributes will get this, * which has all attribute bits clear except the topmost one * (so that we can distinguish "all attributes deliberately clear" * from "didn't specify" if necessary). */ #define MEMTXATTRS_UNSPECIFIED ((MemTxAttrs) { .unspecified = 1 }) #endif