hwstub/qeditor: add support for atomic read/writes

The current code assumed that READ/WRITE would produce atomic read/writes for
8/16/32-bit words, which in turned put assumption on the memcpy function.
Since some memcpy implementation do not always guarantee such strong assumption,
introduce two new operation READ/WRITE_ATOMIC which provide the necessary
tools to do correct read and write to register in a single memory access.

Change-Id: I37451bd5057bb0dcaf5a800d8aef8791c792a090

2 files changed, 8 insertions, 8 deletions

diff --git a/utils/hwstub/tools/hwstub_shell.cpp b/utils/hwstub/tools/hwstub_shell.cpp
index b2838ebed0..30d1ac3b3f 100644
--- a/utils/hwstub/tools/hwstub_shell.cpp
+++ b/utils/hwstub/tools/hwstub_shell.cpp
@@ -144,7 +144,7 @@ typedef void (*hw_writen_fn_t)(lua_State *state, soc_addr_t addr, soc_word_t val
 soc_word_t hw_read8(lua_State *state, soc_addr_t addr)
 {
     uint8_t u;
-    if(hwstub_rw_mem(g_hwdev, 1, addr, &u, sizeof(u)) != sizeof(u))
+    if(hwstub_rw_mem_atomic(g_hwdev, 1, addr, &u, sizeof(u)) != sizeof(u))
         luaL_error(state, "fail to read8 @ %p", addr);
     return u;
 }
@@ -152,7 +152,7 @@ soc_word_t hw_read8(lua_State *state, soc_addr_t addr)
 soc_word_t hw_read16(lua_State *state, soc_addr_t addr)
 {
     uint16_t u;
-    if(hwstub_rw_mem(g_hwdev, 1, addr, &u, sizeof(u)) != sizeof(u))
+    if(hwstub_rw_mem_atomic(g_hwdev, 1, addr, &u, sizeof(u)) != sizeof(u))
         luaL_error(state, "fail to read16 @ %p", addr);
     return u;
 }
@@ -160,7 +160,7 @@ soc_word_t hw_read16(lua_State *state, soc_addr_t addr)
 soc_word_t hw_read32(lua_State *state, soc_addr_t addr)
 {
     uint32_t u;
-    if(hwstub_rw_mem(g_hwdev, 1, addr, &u, sizeof(u)) != sizeof(u))
+    if(hwstub_rw_mem_atomic(g_hwdev, 1, addr, &u, sizeof(u)) != sizeof(u))
         luaL_error(state, "fail to read32 @ %p", addr);
     return u;
 }
@@ -168,21 +168,21 @@ soc_word_t hw_read32(lua_State *state, soc_addr_t addr)
 void hw_write8(lua_State *state, soc_addr_t addr, soc_word_t val)
 {
     uint8_t u = val;
-    if(hwstub_rw_mem(g_hwdev, 0, addr, &u, sizeof(u)) != sizeof(u))
+    if(hwstub_rw_mem_atomic(g_hwdev, 0, addr, &u, sizeof(u)) != sizeof(u))
         luaL_error(state, "fail to write8 @ %p", addr);
 }
 
 void hw_write16(lua_State *state, soc_addr_t addr, soc_word_t val)
 {
     uint16_t u = val;
-    if(hwstub_rw_mem(g_hwdev, 0, addr, &u, sizeof(u)) != sizeof(u))
+    if(hwstub_rw_mem_atomic(g_hwdev, 0, addr, &u, sizeof(u)) != sizeof(u))
         luaL_error(state, "fail to write16 @ %p", addr);
 }
 
 void hw_write32(lua_State *state, soc_addr_t addr, soc_word_t val)
 {
     uint32_t u = val;
-    if(hwstub_rw_mem(g_hwdev, 0, addr, &u, sizeof(u)) != sizeof(u))
+    if(hwstub_rw_mem_atomic(g_hwdev, 0, addr, &u, sizeof(u)) != sizeof(u))
         luaL_error(state, "fail to write32 @ %p", addr);
 }
 
diff --git a/utils/hwstub/tools/init.lua b/utils/hwstub/tools/init.lua
index 1fe0e0d734..aaca8b6c82 100644
--- a/utils/hwstub/tools/init.lua
+++ b/utils/hwstub/tools/init.lua
@@ -38,8 +38,8 @@ do
     h = HELP:create_topic("DEV");
     h:add("This variable redirects to hwstub.dev and provides direct access to the device.");
     h:add("It contains some information about the device and the following methods.");
-    h:add("* read8/16/32(a) reads a 8/16/32-bit integer at address a");
-    h:add("* write8/16/32(a, v) writes the 8/16/32-bit integer v at address a");
+    h:add("* read8/16/32(a) reads a 8/16/32-bit integer at address a atomically");
+    h:add("* write8/16/32(a, v) writes the 8/16/32-bit integer v at address a atomically");
     h:add("* print_log() prints the device log");
 
     h = HELP:create_topic("HW");