[PATCH v8 04/10] hw/riscv/virt: add opt-in RPMI base support

Add the virt machine rpmi=on/off option and wire the initial RPMI Base
transport into machine realization.

The option remains disabled by default and requires TCG plus librpmi.
Invalid accelerator/build combinations fail during machine
initialization. When enabled, virt allocates the RPMI shared-memory
transport, creates the RPMI device, configures Base service metadata,
and emits the corresponding device-tree nodes for firmware discovery.

Signed-off-by: Subrahmanya Lingappa <[email protected]>
---
 hw/misc/meson.build       |  2 +-
 hw/misc/riscv_rpmi-stub.c | 16 +++++++
 hw/riscv/Kconfig          |  1 +
 hw/riscv/meson.build      |  4 +-
 hw/riscv/rpmi-fdt-stub.c  | 37 +++++++++++++++
 hw/riscv/virt.c           | 96 +++++++++++++++++++++++++++++++++++++++
 include/hw/riscv/virt.h   |  3 ++
 7 files changed, 157 insertions(+), 2 deletions(-)
 create mode 100644 hw/misc/riscv_rpmi-stub.c
 create mode 100644 hw/riscv/rpmi-fdt-stub.c

diff --git a/hw/misc/meson.build b/hw/misc/meson.build
index e7c2ebe28f..92c9cd6064 100644
--- a/hw/misc/meson.build
+++ b/hw/misc/meson.build
@@ -170,4 +170,4 @@ system_ss.add(when: 'CONFIG_SBSA_REF', if_true: files('sbsa_ec.c'))
 system_ss.add(when: 'CONFIG_LASI', if_true: files('lasi.c'))
 system_ss.add(when: 'CONFIG_RISCV_RPMI', if_true: [files(
   'riscv_rpmi.c',
-), librpmi])
+), librpmi], if_false: files('riscv_rpmi-stub.c'))
diff --git a/hw/misc/riscv_rpmi-stub.c b/hw/misc/riscv_rpmi-stub.c
new file mode 100644
index 0000000000..dc32b43227
--- /dev/null
+++ b/hw/misc/riscv_rpmi-stub.c
@@ -0,0 +1,16 @@
+/*
+ * RISC-V RPMI stubs.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "hw/misc/riscv_rpmi.h"
+
+DeviceState *riscv_rpmi_create(const RiscvRpmiConfig *cfg G_GNUC_UNUSED,
+                               Error **errp)
+{
+    error_setg(errp, "RISC-V RPMI support is not compiled in");
+    return NULL;
+}
diff --git a/hw/riscv/Kconfig b/hw/riscv/Kconfig
index 54e41a6afc..4e25be113a 100644
--- a/hw/riscv/Kconfig
+++ b/hw/riscv/Kconfig
@@ -49,6 +49,7 @@ config RISCV_VIRT
     imply VIRTIO_VGA
     imply TEST_DEVICES
     imply TPM_TIS_SYSBUS
+    imply RISCV_RPMI
     select DEVICE_TREE
     select RISCV_NUMA
     select GOLDFISH_RTC
diff --git a/hw/riscv/meson.build b/hw/riscv/meson.build
index ae69426eb1..abc2200d22 100644
--- a/hw/riscv/meson.build
+++ b/hw/riscv/meson.build
@@ -3,7 +3,9 @@ riscv_ss.add(files('boot.c'))
 riscv_ss.add(files('fdt-common.c'))
 riscv_ss.add(when: 'CONFIG_RISCV_NUMA', if_true: files('numa.c'))
 riscv_ss.add(files('riscv_hart.c'))
-riscv_ss.add(when: 'CONFIG_RISCV_RPMI', if_true: files('rpmi-fdt.c'))
+riscv_ss.add(when: 'CONFIG_RISCV_RPMI',
+             if_true: files('rpmi-fdt.c'),
+             if_false: files('rpmi-fdt-stub.c'))
 riscv_ss.add(when: 'CONFIG_OPENTITAN', if_true: files('opentitan.c'))
 riscv_ss.add(when: 'CONFIG_RISCV_VIRT', if_true: files('virt.c'))
 riscv_ss.add(when: 'CONFIG_SHAKTI_C', if_true: files('shakti_c.c'))
diff --git a/hw/riscv/rpmi-fdt-stub.c b/hw/riscv/rpmi-fdt-stub.c
new file mode 100644
index 0000000000..28e72adad5
--- /dev/null
+++ b/hw/riscv/rpmi-fdt-stub.c
@@ -0,0 +1,37 @@
+/*
+ * RISC-V RPMI device-tree helper stubs.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "hw/riscv/rpmi-fdt.h"
+
+void riscv_rpmi_fdt_add_mbox(void *fdt G_GNUC_UNUSED,
+                             const RiscvRpmiFdtMboxConfig *cfg G_GNUC_UNUSED,
+                             uint32_t *phandle G_GNUC_UNUSED,
+                             uint32_t *mbox_handle G_GNUC_UNUSED)
+{
+    g_assert_not_reached();
+}
+
+void riscv_rpmi_fdt_add_service(void *fdt G_GNUC_UNUSED,
+                                hwaddr shmem_base G_GNUC_UNUSED,
+                                const char *node_name G_GNUC_UNUSED,
+                                const char *compatible G_GNUC_UNUSED,
+                                uint32_t mbox_handle G_GNUC_UNUSED,
+                                uint32_t service_group G_GNUC_UNUSED,
+                                bool has_mpxy_channel G_GNUC_UNUSED,
+                                uint32_t mpxy_channel G_GNUC_UNUSED)
+{
+    g_assert_not_reached();
+}
+
+void riscv_rpmi_fdt_add_service_node(void *fdt G_GNUC_UNUSED,
+                                     hwaddr shmem_base G_GNUC_UNUSED,
+                                     const RiscvRpmiServiceConfig *service
+                                     G_GNUC_UNUSED,
+                                     uint32_t mbox_handle G_GNUC_UNUSED)
+{
+    g_assert_not_reached();
+}
diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
index 33775a61fd..e52ccfae1f 100644
--- a/hw/riscv/virt.c
+++ b/hw/riscv/virt.c
@@ -45,6 +45,8 @@
 #include "hw/intc/riscv_aplic.h"
 #include "hw/intc/sifive_plic.h"
 #include "hw/misc/sifive_test.h"
+#include "hw/misc/riscv_rpmi.h"
+#include "hw/riscv/rpmi-fdt.h"
 #include "hw/core/platform-bus.h"
 #include "chardev/char.h"
 #include "system/device_tree.h"
@@ -97,6 +99,8 @@ static const MemMapEntry virt_memmap[] = {
     [VIRT_UART0] =        { 0x10000000,         0x100 },
     [VIRT_VIRTIO] =       { 0x10001000,        0x1000 },
     [VIRT_FW_CFG] =       { 0x10100000,          0x18 },
+    [VIRT_RPMI_SHMEM] =   { 0x10200000,       0x20000 },
+    [VIRT_RPMI_DOORBELL] = { 0x10230000,        0x1000 },
     [VIRT_FLASH] =        { 0x20000000,     0x4000000 },
     [VIRT_IMSIC_M] =      { 0x24000000, VIRT_IMSIC_MAX_SIZE },
     [VIRT_IMSIC_S] =      { 0x28000000, VIRT_IMSIC_MAX_SIZE },
@@ -1002,6 +1006,40 @@ static void create_fdt_iommu(RISCVVirtState *s, uint16_t bdf)
     s->pci_iommu_bdf = bdf;
 }
 
+
+static RiscvRpmiConfig virt_rpmi_config(RISCVVirtState *s,
+                                        const uint32_t *hart_ids,
+                                        uint32_t hart_count)
+{
+    return (RiscvRpmiConfig) {
+        .doorbell_base = s->memmap[VIRT_RPMI_DOORBELL].base,
+        .shmem_base = s->memmap[VIRT_RPMI_SHMEM].base,
+        .shmem_size = s->memmap[VIRT_RPMI_SHMEM].size,
+        .a2p_req_size = VIRT_RPMI_A2P_REQ_SIZE,
+        .p2a_req_size = VIRT_RPMI_P2A_REQ_SIZE,
+        .platform_info = "QEMU RISC-V virt RPMI",
+        .hart_ids = hart_ids,
+        .hart_count = hart_count,
+    };
+}
+
+static void create_fdt_rpmi(RISCVVirtState *s, uint32_t *phandle,
+                            uint32_t msi_phandle)
+{
+    RiscvRpmiConfig rpmi_cfg = virt_rpmi_config(s, NULL, 0);
+    uint32_t rpmi_mbox_handle;
+    RiscvRpmiFdtMboxConfig cfg = {
+        .shmem_base = rpmi_cfg.shmem_base,
+        .doorbell_base = rpmi_cfg.doorbell_base,
+        .a2p_req_size = rpmi_cfg.a2p_req_size,
+        .p2a_req_size = rpmi_cfg.p2a_req_size,
+        .doorbell_size = s->memmap[VIRT_RPMI_DOORBELL].size,
+    };
+
+    riscv_rpmi_fdt_add_mbox(MACHINE(s)->fdt, &cfg, phandle,
+                            &rpmi_mbox_handle);
+}
+
 static void finalize_fdt(RISCVVirtState *s)
 {
     uint32_t phandle = 1, irq_mmio_phandle = 1, msi_pcie_phandle = 1;
@@ -1021,6 +1059,10 @@ static void finalize_fdt(RISCVVirtState *s)
     create_fdt_pcie(s, irq_pcie_phandle, msi_pcie_phandle,
                     iommu_sys_phandle);
 
+    if (s->have_rpmi) {
+        create_fdt_rpmi(s, &phandle, msi_pcie_phandle);
+    }
+
     create_fdt_reset(s, &phandle);
 
     create_fdt_uart(s, irq_mmio_phandle);
@@ -1410,6 +1452,18 @@ static void virt_machine_init(MachineState *machine)
         exit(1);
     }
 
+
+    if (s->have_rpmi) {
+#ifndef CONFIG_LIBRPMI
+        error_report("RISC-V RPMI support is not compiled in");
+        exit(1);
+#else
+        if (kvm_enabled()) {
+            error_report("RISC-V RPMI support is not available with KVM");
+            exit(1);
+        }
+#endif
+    }
     /* Initialize sockets */
     mmio_irqchip = virtio_irqchip = pcie_irqchip = NULL;
     for (i = 0; i < socket_count; i++) {
@@ -1552,6 +1606,25 @@ static void virt_machine_init(MachineState *machine)
     /* SiFive Test MMIO device */
     sifive_test_create(s->memmap[VIRT_TEST].base);
 
+    if (s->have_rpmi) {
+        MachineClass *mc = MACHINE_GET_CLASS(machine);
+        const CPUArchIdList *possible_cpus = mc->possible_cpu_arch_ids(machine);
+        g_autofree uint32_t *rpmi_hart_ids =
+            g_new0(uint32_t, machine->smp.cpus);
+        RiscvRpmiConfig rpmi_cfg;
+        Error *local_err = NULL;
+
+        for (i = 0; i < machine->smp.cpus; i++) {
+            rpmi_hart_ids[i] = possible_cpus->cpus[i].arch_id;
+        }
+
+        rpmi_cfg = virt_rpmi_config(s, rpmi_hart_ids, machine->smp.cpus);
+        if (!riscv_rpmi_create(&rpmi_cfg, &local_err)) {
+            error_report_err(local_err);
+            exit(1);
+        }
+    }
+
     /* VirtIO MMIO devices */
     for (i = 0; i < VIRTIO_COUNT; i++) {
         sysbus_create_simple("virtio-mmio",
@@ -1636,6 +1709,7 @@ static void virt_machine_instance_init(Object *obj)
 
     s->oem_id = g_strndup(ACPI_BUILD_APPNAME6, 6);
     s->oem_table_id = g_strndup(ACPI_BUILD_APPNAME8, 8);
+    s->have_rpmi = false;
     s->acpi = ON_OFF_AUTO_AUTO;
     s->iommu_sys = ON_OFF_AUTO_AUTO;
 }
@@ -1710,6 +1784,21 @@ static void virt_set_aclint(Object *obj, bool value, Error **errp)
     s->have_aclint = value;
 }
 
+
+static bool virt_get_rpmi(Object *obj, Error **errp)
+{
+    RISCVVirtState *s = RISCV_VIRT_MACHINE(obj);
+
+    return s->have_rpmi;
+}
+
+static void virt_set_rpmi(Object *obj, bool value, Error **errp)
+{
+    RISCVVirtState *s = RISCV_VIRT_MACHINE(obj);
+
+    s->have_rpmi = value;
+}
+
 bool virt_is_iommu_sys_enabled(RISCVVirtState *s)
 {
     return s->iommu_sys == ON_OFF_AUTO_ON;
@@ -1831,6 +1920,13 @@ static void virt_machine_class_init(ObjectClass *oc, const void *data)
                                           "enable/disable emulating "
                                           "ACLINT devices");
 
+
+    object_class_property_add_bool(oc, "rpmi", virt_get_rpmi,
+                                   virt_set_rpmi);
+    object_class_property_set_description(oc, "rpmi",
+                                          "Set on/off to enable/disable "
+                                          "RISC-V RPMI devices");
+
     object_class_property_add_str(oc, "aia", virt_get_aia,
                                   virt_set_aia);
     object_class_property_set_description(oc, "aia",
diff --git a/include/hw/riscv/virt.h b/include/hw/riscv/virt.h
index 18a2a323a3..f7c48613bf 100644
--- a/include/hw/riscv/virt.h
+++ b/include/hw/riscv/virt.h
@@ -55,6 +55,7 @@ struct RISCVVirtState {
 
     int fdt_size;
     bool have_aclint;
+    bool have_rpmi;
     RISCVVirtAIAType aia_type;
     int aia_guests;
     char *oem_id;
@@ -79,6 +80,8 @@ enum {
     VIRT_UART0,
     VIRT_VIRTIO,
     VIRT_FW_CFG,
+    VIRT_RPMI_SHMEM,
+    VIRT_RPMI_DOORBELL,
     VIRT_IMSIC_M,
     VIRT_IMSIC_S,
     VIRT_FLASH,
-- 
2.43.0