From cc05c43ad942165ecc6ffd39e41991bee43af044 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Sun, 26 Apr 2015 16:49:23 +0100 Subject: memory: Define API for MemoryRegionOps to take attrs and return status MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Define an API so that devices can register MemoryRegionOps whose read and write callback functions are passed an arbitrary pointer to some transaction attributes and can return a success-or-failure status code. This will allow us to model devices which: * behave differently for ARM Secure/NonSecure memory accesses * behave differently for privileged/unprivileged accesses * may return a transaction failure (causing a guest exception) for erroneous accesses This patch defines the new API and plumbs the attributes parameter through to the memory.c public level functions io_mem_read() and io_mem_write(), where it is currently dummied out. The success/failure response indication is also propagated out to io_mem_read() and io_mem_write(), which retain the old-style boolean true-for-error return. Signed-off-by: Peter Maydell Acked-by: Paolo Bonzini Reviewed-by: Alex Bennée --- include/exec/memory.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'include/exec/memory.h') diff --git a/include/exec/memory.h b/include/exec/memory.h index 06ffa1d185..703d9e5f8f 100644 --- a/include/exec/memory.h +++ b/include/exec/memory.h @@ -28,6 +28,7 @@ #ifndef CONFIG_USER_ONLY #include "exec/hwaddr.h" #endif +#include "exec/memattrs.h" #include "qemu/queue.h" #include "qemu/int128.h" #include "qemu/notify.h" @@ -68,6 +69,16 @@ struct IOMMUTLBEntry { IOMMUAccessFlags perm; }; +/* New-style MMIO accessors can indicate that the transaction failed. + * A zero (MEMTX_OK) response means success; anything else is a failure + * of some kind. The memory subsystem will bitwise-OR together results + * if it is synthesizing an operation from multiple smaller accesses. + */ +#define MEMTX_OK 0 +#define MEMTX_ERROR (1U << 0) /* device returned an error */ +#define MEMTX_DECODE_ERROR (1U << 1) /* nothing at that address */ +typedef uint32_t MemTxResult; + /* * Memory region callbacks */ @@ -84,6 +95,17 @@ struct MemoryRegionOps { uint64_t data, unsigned size); + MemTxResult (*read_with_attrs)(void *opaque, + hwaddr addr, + uint64_t *data, + unsigned size, + MemTxAttrs attrs); + MemTxResult (*write_with_attrs)(void *opaque, + hwaddr addr, + uint64_t data, + unsigned size, + MemTxAttrs attrs); + enum device_endian endianness; /* Guest-visible constraints: */ struct { -- cgit 1.4.1