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

[Chao Liu <chao.liu.zevorn@gmail.com>]

On Fri, Jul 17, 2026 at 10:56:17AM +0800, Daniel Henrique Barboza wrote:
> 
> 
> 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 <163wangjack@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
> 
Yes, sir. :)

Thanks,
Chao

> 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 <163wangjack@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;
> > > 
>