Re: [RFC PATCH 2/2] hw/riscv/k230: wire up the RMU device

[Daniel Henrique Barboza]

On 7/17/2026 10:41 AM, Chao Liu wrote:

On Thu, Jul 16, 2026 at 02:56:30PM +0800, Daniel Henrique Barboza wrote:

Hi Daniel,

Hi,

On 7/9/2026 12:12 AM, jack wang wrote:

From: Jack Wang <163wangj...@gmail.com>

Replace the "rmu" create_unimplemented_device() stub with a real
K230RmuState instance mapped at the K230_DEV_RMU memmap entry, select
K230_RMU from the K230 Kconfig, and document the device.

So, as I said in patch 1, applying this patch will fix the qtest that you
introduced there.  I believe we want to either squash this patch in patch
1 or move the qtest creation to this patch.  Both are fine to me.

Closes: gevico/qemu-camp-2026-k230#11

Not sure what gevico is (seems like a bootcamp, according to Google at least)  
but
the "Closes" tag usually contains a gitlab bug or any other link that is 
publicly
available.  It's better to remove it.

I believe this link refers to:
https://github.com/gevico/qemu-camp-2026-k230/issues/11

However, according to the QEMU development collaboration workflow,
we don't need to add it.

Gevico, here is the English transliteration for the Chinese "格维". This
is a major open-source community in China focused on technical software,
which I currently organize and own.

Within our community, we run a QEMU technical training camp primarily
centered on the RISC-V architecture and exploratory work regarding
GPGPU microarchitecture.

One of our key projects involves hardware modeling for the K230, where
we are implementing a digital satellite-borne computer. The recent
contributions seen upstream were primarily patches sent by participants
of this project. We are currently in the process of contributing our
results from this stage to the QEMU upstream.

Thanks for the info.  This seems very interesting indeed, and please keep
the QEMU contributions flowing :D


Cheers,
Daniel

If you are interested in this, you can visit the link below.
https://qemu.gevico.online/tutorial/2026/ch3/qemu-k230/

Thanks,
Chao

Thanks,
Daniel

Signed-off-by: Jack Wang <163wangj...@gmail.com>
---
   docs/system/riscv/k230.rst |  1 +
   hw/riscv/Kconfig           |  1 +
   hw/riscv/k230.c            | 10 +++++++---
   include/hw/riscv/k230.h    |  2 ++
   4 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/docs/system/riscv/k230.rst b/docs/system/riscv/k230.rst
index cea8202e55..3f2313a127 100644
--- a/docs/system/riscv/k230.rst
+++ b/docs/system/riscv/k230.rst
@@ -19,6 +19,7 @@ The ``k230`` machine supports the following devices:
   * Core Local Interruptor (CLINT)
   * Platform-Level Interrupt Controller (PLIC)
   * 2 K230 Watchdog Timer
+* K230 Reset Management Unit (RMU)
   * 5 UART
   Boot options
diff --git a/hw/riscv/Kconfig b/hw/riscv/Kconfig
index 54e41a6afc..bffa4e69c8 100644
--- a/hw/riscv/Kconfig
+++ b/hw/riscv/Kconfig
@@ -149,3 +149,4 @@ config K230
       select SERIAL_MM
       select UNIMP
       select K230_WDT
+    select K230_RMU
diff --git a/hw/riscv/k230.c b/hw/riscv/k230.c
index 502281c52c..b55e90c0d2 100644
--- a/hw/riscv/k230.c
+++ b/hw/riscv/k230.c
@@ -110,6 +110,7 @@ static void k230_soc_init(Object *obj)
       object_initialize_child(obj, "c908-cpu", cpu0, TYPE_RISCV_HART_ARRAY);
       object_initialize_child(obj, "k230-wdt0", &s->wdt[0], TYPE_K230_WDT);
       object_initialize_child(obj, "k230-wdt1", &s->wdt[1], TYPE_K230_WDT);
+    object_initialize_child(obj, "k230-rmu",  &s->rmu,    TYPE_K230_RMU);
       qdev_prop_set_uint32(DEVICE(cpu0), "hartid-base", 0);
       qdev_prop_set_string(DEVICE(cpu0), "cpu-type", 
TYPE_RISCV_CPU_THEAD_C908);
@@ -206,6 +207,12 @@ static void k230_soc_realize(DeviceState *dev, Error 
**errp)
       sysbus_connect_irq(SYS_BUS_DEVICE(&s->wdt[1]), 0,
                          qdev_get_gpio_in(DEVICE(s->c908_plic), 
K230_WDT1_IRQ));
+    /* RMU (reset management unit) */
+    if (!sysbus_realize(SYS_BUS_DEVICE(&s->rmu), errp)) {
+        return;
+    }
+    sysbus_mmio_map(SYS_BUS_DEVICE(&s->rmu), 0, memmap[K230_DEV_RMU].base);
+
       /* unimplemented devices */
       create_unimplemented_device("kpu.l2-cache",
                                   memmap[K230_DEV_KPU_L2_CACHE].base,
@@ -268,9 +275,6 @@ static void k230_soc_realize(DeviceState *dev, Error **errp)
       create_unimplemented_device("cmu", memmap[K230_DEV_CMU].base,
                                   memmap[K230_DEV_CMU].size);
-    create_unimplemented_device("rmu", memmap[K230_DEV_RMU].base,
-                                memmap[K230_DEV_RMU].size);
-
       create_unimplemented_device("boot", memmap[K230_DEV_BOOT].base,
                                   memmap[K230_DEV_BOOT].size);
diff --git a/include/hw/riscv/k230.h b/include/hw/riscv/k230.h
index 592e1c26bf..13f2a1ab0b 100644
--- a/include/hw/riscv/k230.h
+++ b/include/hw/riscv/k230.h
@@ -18,6 +18,7 @@
   #include "hw/core/boards.h"
   #include "hw/riscv/riscv_hart.h"
   #include "hw/watchdog/k230_wdt.h"
+#include "hw/misc/k230_rmu.h"
   #define C908_CPU_HARTID   (0)
@@ -33,6 +34,7 @@ typedef struct K230SoCState {
       RISCVHartArrayState c908_cpu; /* Small core */
       K230WdtState wdt[2];
+    K230RmuState rmu;
       MemoryRegion sram;
       MemoryRegion bootrom;