From c99a29e702528698c0ce2590f06ca7ff239f7c39 Mon Sep 17 00:00:00 2001 From: Yongji Xie Date: Mon, 27 Feb 2017 12:52:44 +0800 Subject: [PATCH] memory: Introduce DEVICE_HOST_ENDIAN for ram device At the moment ram device's memory regions are DEVICE_NATIVE_ENDIAN. It's incorrect. This memory region is backed by a MMIO area in host, so the uint64_t data that MemoryRegionOps read from/write to this area should be host-endian rather than target-endian. Hence, current code does not work when target and host endianness are different which is the most common case on PPC64. To fix it, this introduces DEVICE_HOST_ENDIAN for the ram device. This has been tested on PPC64 BE/LE host/guest in all possible combinations including TCG. Suggested-by: Paolo Bonzini Signed-off-by: Yongji Xie Message-Id: <1488171164-28319-1-git-send-email-xyjxie@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini --- include/exec/cpu-common.h | 6 ++++++ memory.c | 2 +- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h index 8c305aa4fa..b62f0d82e4 100644 --- a/include/exec/cpu-common.h +++ b/include/exec/cpu-common.h @@ -36,6 +36,12 @@ enum device_endian { DEVICE_LITTLE_ENDIAN, }; +#if defined(HOST_WORDS_BIGENDIAN) +#define DEVICE_HOST_ENDIAN DEVICE_BIG_ENDIAN +#else +#define DEVICE_HOST_ENDIAN DEVICE_LITTLE_ENDIAN +#endif + /* address in the RAM (different from a physical address) */ #if defined(CONFIG_XEN_BACKEND) typedef uint64_t ram_addr_t; diff --git a/memory.c b/memory.c index d61caee867..573fa6e5f6 100644 --- a/memory.c +++ b/memory.c @@ -1182,7 +1182,7 @@ static void memory_region_ram_device_write(void *opaque, hwaddr addr, static const MemoryRegionOps ram_device_mem_ops = { .read = memory_region_ram_device_read, .write = memory_region_ram_device_write, - .endianness = DEVICE_NATIVE_ENDIAN, + .endianness = DEVICE_HOST_ENDIAN, .valid = { .min_access_size = 1, .max_access_size = 8, -- 2.11.4.GIT