[Qemu-devel] [PATCH v5 1/8] aspeed: use a ROM memory region to catch invalid writes

["Cédric Le Goater" <clg@kaod.org>]

Some legacy firmwares access unimplemented addresses on the Aspeed SoC
(old U-Boot code using variables in the bss when it shouldn't do).
Let's use a ROM memory region to catch the invalid writes and support
new boards without using the 'ignore_memory_transaction_failures'
flag.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
---

 Changes since v4 :

 - use a ROM memory region

 
 hw/arm/aspeed.c | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/hw/arm/aspeed.c b/hw/arm/aspeed.c
index ab895ad490af..d88a8b5120b6 100644
--- a/hw/arm/aspeed.c
+++ b/hw/arm/aspeed.c
@@ -166,6 +166,23 @@ static void aspeed_board_init_flashes(AspeedSMCState *s, const char *flashtype,
     }
 }
 
+/*
+ * This is to track invalid writes done in the ROM by some legacy
+ * firmwares
+ */
+static void boot_rom_write(void *opaque, hwaddr offset, uint64_t value,
+                           unsigned size)
+{
+    qemu_log_mask(LOG_GUEST_ERROR,
+                  "%s: 0x%" HWADDR_PRIx " <- 0x%" PRIx64 " [%u]\n",
+                  __func__, offset, value, size);
+}
+
+static const MemoryRegionOps boot_rom_ops = {
+    .write = boot_rom_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
 static void aspeed_board_init(MachineState *machine,
                               const AspeedBoardConfig *cfg)
 {
@@ -216,8 +233,9 @@ static void aspeed_board_init(MachineState *machine,
          * SoC and 128MB for the AST2500 SoC, which is twice as big as
          * needed by the flash modules of the Aspeed machines.
          */
-        memory_region_init_rom_nomigrate(boot_rom, OBJECT(bmc), "aspeed.boot_rom",
-                               fl->size, &error_abort);
+        memory_region_init_rom_device(boot_rom, OBJECT(bmc), &boot_rom_ops,
+                                      NULL, "aspeed.boot_rom", fl->size,
+                                      &error_abort);
         memory_region_add_subregion(get_system_memory(), FIRMWARE_ADDR,
                                     boot_rom);
         write_boot_rom(drive0, FIRMWARE_ADDR, fl->size, &error_abort);
-- 
2.13.6