Re: [PATCH 03/16] hw/intc/riscv_imsic: Take a MemoryRegion for the created device

[Daniel Henrique Barboza]

On 8/26/2026 7:05 PM, Joel Stanley wrote:

riscv_imsic_create() maps the device it creates into system_memory,
which prevents its use by SoCs that map devices into their own memory
container.

Add a MemoryRegion parameter and map the device into it instead of
calling sysbus_mmio_map(). All callers pass system_memory, so there is
no change in behaviour.

Signed-off-by: Joel Stanley <j...@jms.id.au>
---

Reviewed-by: Daniel Henrique Barboza <daniel.barb...@oss.qualcomm.com>

  include/hw/intc/riscv_imsic.h | 3 ++-
  hw/intc/riscv_imsic.c         | 6 ++++--
  hw/riscv/aia.c                | 6 ++++--
  hw/riscv/xiangshan_kmh.c      | 5 +++--
  4 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/include/hw/intc/riscv_imsic.h b/include/hw/intc/riscv_imsic.h
index fae999731dff..8295b1f14452 100644
--- a/include/hw/intc/riscv_imsic.h
+++ b/include/hw/intc/riscv_imsic.h
@@ -62,7 +62,8 @@ struct RISCVIMSICState {
      uint32_t num_irqs;
  };

-DeviceState *riscv_imsic_create(hwaddr addr, uint32_t hartid, bool mmode,

+DeviceState *riscv_imsic_create(MemoryRegion *mr, hwaddr addr,
+                                uint32_t hartid, bool mmode,
                                  uint32_t num_pages, uint32_t num_ids);

#endif

diff --git a/hw/intc/riscv_imsic.c b/hw/intc/riscv_imsic.c
index d6b46cdca220..26dd10a0462c 100644
--- a/hw/intc/riscv_imsic.c
+++ b/hw/intc/riscv_imsic.c
@@ -495,7 +495,8 @@ type_init(riscv_imsic_register_types)
  /*
   * Create IMSIC device.
   */
-DeviceState *riscv_imsic_create(hwaddr addr, uint32_t hartid, bool mmode,
+DeviceState *riscv_imsic_create(MemoryRegion *mr, hwaddr addr,
+                                uint32_t hartid, bool mmode,
                                  uint32_t num_pages, uint32_t num_ids)
  {
      DeviceState *dev = qdev_new(TYPE_RISCV_IMSIC);
@@ -518,7 +519,8 @@ DeviceState *riscv_imsic_create(hwaddr addr, uint32_t 
hartid, bool mmode,
      qdev_prop_set_uint32(dev, "num-irqs", num_ids + 1);

sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);

-    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, addr);
+    memory_region_add_subregion(mr, addr,
+        sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0));

if (!kvm_irqchip_in_kernel()) {

          for (i = 0; i < num_pages; i++) {
diff --git a/hw/riscv/aia.c b/hw/riscv/aia.c
index 651552c8f970..49cb14349f00 100644
--- a/hw/riscv/aia.c
+++ b/hw/riscv/aia.c
@@ -52,7 +52,8 @@ DeviceState *riscv_create_aia(MemoryRegion *mr, bool msimode, 
int aia_guests,
              /* Per-socket M-level IMSICs */
              addr = imsic_m->base + socket * (1U << 
IMSIC_MMIO_GROUP_MIN_SHIFT);
              for (i = 0; i < hart_count; i++) {
-                riscv_imsic_create(addr + i * m_imsic_stride,
+                riscv_imsic_create(mr,
+                                   addr + i * m_imsic_stride,
                                     base_hartid + i, true, 1,
                                     num_msis);
              }
@@ -61,7 +62,8 @@ DeviceState *riscv_create_aia(MemoryRegion *mr, bool msimode, 
int aia_guests,
          /* Per-socket S-level IMSICs */
          addr = imsic_s->base + socket * (1U << IMSIC_MMIO_GROUP_MIN_SHIFT);
          for (i = 0; i < hart_count; i++) {
-            riscv_imsic_create(addr + i * s_imsic_stride,
+            riscv_imsic_create(mr,
+                               addr + i * s_imsic_stride,
                                 base_hartid + i, false, 1 + aia_guests,
                                 num_msis);
          }
diff --git a/hw/riscv/xiangshan_kmh.c b/hw/riscv/xiangshan_kmh.c
index 94f9d02a00b9..9eb608f8c578 100644
--- a/hw/riscv/xiangshan_kmh.c
+++ b/hw/riscv/xiangshan_kmh.c
@@ -65,14 +65,15 @@ static DeviceState *xiangshan_kmh_create_aia(uint32_t 
num_harts)
      /* M-level IMSICs */
      addr = memmap[XIANGSHAN_KMH_IMSIC_M].base;
      for (i = 0; i < num_harts; i++) {
-        riscv_imsic_create(addr + i * IMSIC_HART_SIZE(0), i, true,
+        riscv_imsic_create(get_system_memory(),
+                           addr + i * IMSIC_HART_SIZE(0), i, true,
                             1, XIANGSHAN_KMH_IMSIC_NUM_IDS);
      }

/* S-level IMSICs */

      addr = memmap[XIANGSHAN_KMH_IMSIC_S].base;
      for (i = 0; i < num_harts; i++) {
-        riscv_imsic_create(addr +
+        riscv_imsic_create(get_system_memory(), addr +
                             i * 
IMSIC_HART_SIZE(XIANGSHAN_KMH_IMSIC_GUEST_BITS),
                             i, false, 1 + XIANGSHAN_KMH_IMSIC_GUEST_BITS,
                             XIANGSHAN_KMH_IMSIC_NUM_IDS);