[PATCH v3 3/3] hw/arm: Integrate Aspeed OTP memory into AST10x0 and AST2600 SoCs

[Kane Chen]

From: Kane-Chen-AS <kane_chen@aspeedtech.com>

This patch wires up the OTP memory device (`aspeed.otpmem`) into the
AST1030 and AST2600 SoC models. The device is initialized, attached
to a backing block drive (`-drive id=otpmem`) and linked to the SBC
controller via a QOM link.

The default OTP memory image can be generated using the following
command.
```bash
for i in $(seq 1 2048); do
  printf '\x00\x00\x00\x00\xff\xff\xff\xff'
done > otpmem.img
```

To load the OTP memory image into the guest, use:
```bash
./qemu-system-arm \
  -drive id=otpmem,file=otpmem.img,if=none,format=raw \
  ...
```

Note: Do not use the -snapshot option, or OTP data writes will not
persist to the image file.

Signed-off-by: Kane-Chen-AS <kane_chen@aspeedtech.com>
---
 hw/arm/aspeed_ast10x0.c     | 19 +++++++++++++++++++
 hw/arm/aspeed_ast2600.c     | 19 +++++++++++++++++++
 include/hw/arm/aspeed_soc.h |  2 ++
 3 files changed, 40 insertions(+)

diff --git a/hw/arm/aspeed_ast10x0.c b/hw/arm/aspeed_ast10x0.c
index ec329f4991..eaa70feb9f 100644
--- a/hw/arm/aspeed_ast10x0.c
+++ b/hw/arm/aspeed_ast10x0.c
@@ -15,6 +15,7 @@
 #include "system/system.h"
 #include "hw/qdev-clock.h"
 #include "hw/misc/unimp.h"
+#include "system/block-backend-global-state.h"
 #include "hw/arm/aspeed_soc.h"
 
 #define ASPEED_SOC_IOMEM_SIZE 0x00200000
@@ -156,6 +157,8 @@ static void aspeed_soc_ast1030_init(Object *obj)
 
     object_initialize_child(obj, "sbc", &s->sbc, TYPE_ASPEED_SBC);
 
+    object_initialize_child(obj, "otpmem", &s->otpmem, TYPE_ASPEED_OTPMEM);
+
     for (i = 0; i < sc->wdts_num; i++) {
         snprintf(typename, sizeof(typename), "aspeed.wdt-%s", socname);
         object_initialize_child(obj, "wdt[*]", &s->wdt[i], typename);
@@ -194,6 +197,7 @@ static void aspeed_soc_ast1030_realize(DeviceState 
*dev_soc, Error **errp)
     Error *err = NULL;
     int i;
     g_autofree char *sram_name = NULL;
+    BlockBackend *blk;
 
     if (!clock_has_source(s->sysclk)) {
         error_setg(errp, "sysclk clock must be wired up by the board code");
@@ -359,6 +363,21 @@ static void aspeed_soc_ast1030_realize(DeviceState 
*dev_soc, Error **errp)
                         ASPEED_SMC_GET_CLASS(&s->spi[i])->flash_window_base);
     }
 
+    /* OTP memory */
+    blk = blk_by_name(ASPEED_OTPMEM_DRIVE);
+    if (blk) {
+        blk_set_perm(blk, BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE,
+                     0, &error_fatal);
+        qdev_prop_set_drive(DEVICE(&s->otpmem), "drive", blk);
+
+        if (!sysbus_realize(SYS_BUS_DEVICE(&s->otpmem), errp)) {
+            return;
+        }
+        /* Assign OTP memory to SBC */
+        object_property_set_link(OBJECT(&s->sbc), "otpmem",
+                                 OBJECT(&s->otpmem), &error_abort);
+    }
+
     /* Secure Boot Controller */
     if (!sysbus_realize(SYS_BUS_DEVICE(&s->sbc), errp)) {
         return;
diff --git a/hw/arm/aspeed_ast2600.c b/hw/arm/aspeed_ast2600.c
index 1f994ba26c..9fe3eeeb0e 100644
--- a/hw/arm/aspeed_ast2600.c
+++ b/hw/arm/aspeed_ast2600.c
@@ -10,6 +10,7 @@
 #include "qemu/osdep.h"
 #include "qapi/error.h"
 #include "hw/misc/unimp.h"
+#include "system/block-backend-global-state.h"
 #include "hw/arm/aspeed_soc.h"
 #include "qemu/module.h"
 #include "qemu/error-report.h"
@@ -263,6 +264,8 @@ static void aspeed_soc_ast2600_init(Object *obj)
 
     object_initialize_child(obj, "sbc", &s->sbc, TYPE_ASPEED_SBC);
 
+    object_initialize_child(obj, "otpmem", &s->otpmem, TYPE_ASPEED_OTPMEM);
+
     object_initialize_child(obj, "iomem", &s->iomem, 
TYPE_UNIMPLEMENTED_DEVICE);
     object_initialize_child(obj, "video", &s->video, 
TYPE_UNIMPLEMENTED_DEVICE);
     object_initialize_child(obj, "dpmcu", &s->dpmcu, 
TYPE_UNIMPLEMENTED_DEVICE);
@@ -293,6 +296,7 @@ static void aspeed_soc_ast2600_realize(DeviceState *dev, 
Error **errp)
     AspeedSoCClass *sc = ASPEED_SOC_GET_CLASS(s);
     qemu_irq irq;
     g_autofree char *sram_name = NULL;
+    BlockBackend *blk;
 
     /* Default boot region (SPI memory or ROMs) */
     memory_region_init(&s->spi_boot_container, OBJECT(s),
@@ -628,6 +632,21 @@ static void aspeed_soc_ast2600_realize(DeviceState *dev, 
Error **errp)
         sysbus_connect_irq(SYS_BUS_DEVICE(&s->i3c.devices[i]), 0, irq);
     }
 
+    /* OTP memory */
+    blk = blk_by_name(ASPEED_OTPMEM_DRIVE);
+    if (blk) {
+        blk_set_perm(blk, BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE,
+                     0, &error_fatal);
+        qdev_prop_set_drive(DEVICE(&s->otpmem), "drive", blk);
+
+        if (!sysbus_realize(SYS_BUS_DEVICE(&s->otpmem), errp)) {
+            return;
+        }
+        /* Assign OTP memory to SBC */
+        object_property_set_link(OBJECT(&s->sbc), "otpmem",
+                                 OBJECT(&s->otpmem), &error_abort);
+    }
+
     /* Secure Boot Controller */
     if (!sysbus_realize(SYS_BUS_DEVICE(&s->sbc), errp)) {
         return;
diff --git a/include/hw/arm/aspeed_soc.h b/include/hw/arm/aspeed_soc.h
index f069d17d16..2d15c6047a 100644
--- a/include/hw/arm/aspeed_soc.h
+++ b/include/hw/arm/aspeed_soc.h
@@ -36,6 +36,7 @@
 #include "hw/usb/hcd-ehci.h"
 #include "qom/object.h"
 #include "hw/misc/aspeed_lpc.h"
+#include "hw/misc/aspeed_otpmem.h"
 #include "hw/misc/unimp.h"
 #include "hw/misc/aspeed_peci.h"
 #include "hw/fsi/aspeed_apb2opb.h"
@@ -73,6 +74,7 @@ struct AspeedSoCState {
     AspeedSMCState spi[ASPEED_SPIS_NUM];
     EHCISysBusState ehci[ASPEED_EHCIS_NUM];
     AspeedSBCState sbc;
+    AspeedOTPMemState otpmem;
     AspeedSLIState sli;
     AspeedSLIState sliio;
     MemoryRegion secsram;
-- 
2.43.0