On 11/5/25 3:50 PM, Michael Levit wrote:
From: Michael <[email protected]>
Introduce NEORV32 RV32 CPU type under target/riscv, wire NEORV32 vendor ID,
and add a vendor CSR (CSR_MXISA) guarded by mvendorid match, plus meson glue.
Signed-off-by: Michael Levit <[email protected]>
---
target/riscv/cpu-qom.h | 2 ++
target/riscv/cpu.c | 18 ++++++++++++++
target/riscv/cpu.h | 3 +++
target/riscv/cpu_cfg.h | 1 +
target/riscv/cpu_cfg_fields.h.inc | 1 +
target/riscv/cpu_vendorid.h | 2 ++
target/riscv/meson.build | 1 +
target/riscv/neorv32_csr.c | 40 +++++++++++++++++++++++++++++++
8 files changed, 68 insertions(+)
create mode 100644 target/riscv/neorv32_csr.c
diff --git a/target/riscv/cpu-qom.h b/target/riscv/cpu-qom.h
index 75f4e43408..d091807160 100644
--- a/target/riscv/cpu-qom.h
+++ b/target/riscv/cpu-qom.h
@@ -43,6 +43,7 @@
#define TYPE_RISCV_CPU_RVA23U64 RISCV_CPU_TYPE_NAME("rva23u64")
#define TYPE_RISCV_CPU_RVA23S64 RISCV_CPU_TYPE_NAME("rva23s64")
#define TYPE_RISCV_CPU_IBEX RISCV_CPU_TYPE_NAME("lowrisc-ibex")
+#define TYPE_RISCV_CPU_NEORV32 RISCV_CPU_TYPE_NAME("neorv32")
#define TYPE_RISCV_CPU_SHAKTI_C RISCV_CPU_TYPE_NAME("shakti-c")
#define TYPE_RISCV_CPU_SIFIVE_E RISCV_CPU_TYPE_NAME("sifive-e")
#define TYPE_RISCV_CPU_SIFIVE_E31 RISCV_CPU_TYPE_NAME("sifive-e31")
@@ -58,6 +59,7 @@
#define TYPE_RISCV_CPU_XIANGSHAN_KMH
RISCV_CPU_TYPE_NAME("xiangshan-kunminghu")
#define TYPE_RISCV_CPU_HOST RISCV_CPU_TYPE_NAME("host")
+
Extra blank line.
OBJECT_DECLARE_CPU_TYPE(RISCVCPU, RISCVCPUClass, RISCV_CPU)
#endif /* RISCV_CPU_QOM_H */
diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 73d4280d7c..ffe99f71e1 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -233,6 +233,7 @@ const RISCVIsaExtData isa_edata_arr[] = {
ISA_EXT_DATA_ENTRY(svrsw60t59b, PRIV_VERSION_1_13_0, ext_svrsw60t59b),
ISA_EXT_DATA_ENTRY(svukte, PRIV_VERSION_1_13_0, ext_svukte),
ISA_EXT_DATA_ENTRY(svvptc, PRIV_VERSION_1_13_0, ext_svvptc),
+ ISA_EXT_DATA_ENTRY(xneorv32xisa, PRIV_VERSION_1_10_0, ext_xneorv32xisa),
ISA_EXT_DATA_ENTRY(xtheadba, PRIV_VERSION_1_11_0, ext_xtheadba),
ISA_EXT_DATA_ENTRY(xtheadbb, PRIV_VERSION_1_11_0, ext_xtheadbb),
ISA_EXT_DATA_ENTRY(xtheadbs, PRIV_VERSION_1_11_0, ext_xtheadbs),
@@ -1366,6 +1367,7 @@ const RISCVCPUMultiExtConfig riscv_cpu_vendor_exts[] = {
MULTI_EXT_CFG_BOOL("xtheadmempair", ext_xtheadmempair, false),
MULTI_EXT_CFG_BOOL("xtheadsync", ext_xtheadsync, false),
MULTI_EXT_CFG_BOOL("xventanacondops", ext_XVentanaCondOps, false),
+ MULTI_EXT_CFG_BOOL("xneorv32xisa", ext_xneorv32xisa, false),
{ },
};
@@ -3032,6 +3034,7 @@ static const TypeInfo riscv_cpu_type_infos[] = {
.cfg.pmp_regions = 8
),
+
Extra blank line here too.
Without the extra blank lines:
Reviewed-by: Daniel Henrique Barboza <[email protected]>
#if defined(TARGET_RISCV32) || \
(defined(TARGET_RISCV64) && !defined(CONFIG_USER_ONLY))
DEFINE_RISCV_CPU(TYPE_RISCV_CPU_BASE32, TYPE_RISCV_DYNAMIC_CPU,
@@ -3075,6 +3078,21 @@ static const TypeInfo riscv_cpu_type_infos[] = {
.misa_mxl_max = MXL_RV32,
.misa_ext = RVE
),
+ DEFINE_RISCV_CPU(TYPE_RISCV_CPU_NEORV32, TYPE_RISCV_VENDOR_CPU,
+ .misa_mxl_max = MXL_RV32,
+ .misa_ext = RVI | RVM | RVA | RVC | RVU,
+ .priv_spec = PRIV_VERSION_1_10_0,
+
+ .cfg.max_satp_mode = VM_1_10_MBARE,
+ .cfg.ext_zifencei = true,
+ .cfg.ext_zicsr = true,
+ .cfg.pmp = true,
+ .cfg.pmp_regions = 16,
+ .cfg.mvendorid = NEORV32_VENDOR_ID,
+#ifndef CONFIG_USER_ONLY
+ .custom_csrs = neorv32_csr_list
+#endif
+ ),
#endif
#if (defined(TARGET_RISCV64) && !defined(CONFIG_USER_ONLY))
diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index 36e7f10037..6a9918a25a 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -985,5 +985,8 @@ const char *satp_mode_str(uint8_t satp_mode, bool
is_32_bit);
/* In th_csr.c */
extern const RISCVCSR th_csr_list[];
+/* Implemented in neorv32_csr.c */
+extern const RISCVCSR neorv32_csr_list[];
+
const char *priv_spec_to_str(int priv_version);
#endif /* RISCV_CPU_H */
diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
index aa28dc8d7e..9ad38506e4 100644
--- a/target/riscv/cpu_cfg.h
+++ b/target/riscv/cpu_cfg.h
@@ -64,5 +64,6 @@ MATERIALISE_EXT_PREDICATE(xtheadmemidx)
MATERIALISE_EXT_PREDICATE(xtheadmempair)
MATERIALISE_EXT_PREDICATE(xtheadsync)
MATERIALISE_EXT_PREDICATE(XVentanaCondOps)
+MATERIALISE_EXT_PREDICATE(xneorv32xisa)
#endif
diff --git a/target/riscv/cpu_cfg_fields.h.inc
b/target/riscv/cpu_cfg_fields.h.inc
index a154ecdc79..b84e1bd287 100644
--- a/target/riscv/cpu_cfg_fields.h.inc
+++ b/target/riscv/cpu_cfg_fields.h.inc
@@ -147,6 +147,7 @@ BOOL_FIELD(ext_xtheadmemidx)
BOOL_FIELD(ext_xtheadmempair)
BOOL_FIELD(ext_xtheadsync)
BOOL_FIELD(ext_XVentanaCondOps)
+BOOL_FIELD(ext_xneorv32xisa)
BOOL_FIELD(mmu)
BOOL_FIELD(pmp)
diff --git a/target/riscv/cpu_vendorid.h b/target/riscv/cpu_vendorid.h
index 96b6b9c2cb..66a8f30b81 100644
--- a/target/riscv/cpu_vendorid.h
+++ b/target/riscv/cpu_vendorid.h
@@ -7,4 +7,6 @@
#define VEYRON_V1_MIMPID 0x111
#define VEYRON_V1_MVENDORID 0x61f
+#define NEORV32_VENDOR_ID 0xF0000001
+
#endif /* TARGET_RISCV_CPU_VENDORID_H */
diff --git a/target/riscv/meson.build b/target/riscv/meson.build
index fdefe88ccd..44e706ad3f 100644
--- a/target/riscv/meson.build
+++ b/target/riscv/meson.build
@@ -40,6 +40,7 @@ riscv_system_ss.add(files(
'th_csr.c',
'time_helper.c',
'riscv-qmp-cmds.c',
+ 'neorv32_csr.c',
))
subdir('tcg')
diff --git a/target/riscv/neorv32_csr.c b/target/riscv/neorv32_csr.c
new file mode 100644
index 0000000000..3b0f0cab05
--- /dev/null
+++ b/target/riscv/neorv32_csr.c
@@ -0,0 +1,40 @@
+/*
+ * NEORV32-specific CSR.
+ *
+ * Copyright (c) 2025 Michael Levit
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "cpu.h"
+#include "cpu_vendorid.h"
+
+#define CSR_MXISA (0xfc0)
+
+static RISCVException smode(CPURISCVState *env, int csrno)
+{
+ return RISCV_EXCP_NONE;
+}
+
+static RISCVException read_neorv32_xisa(CPURISCVState *env, int csrno,
+ target_ulong *val)
+{
+ /* We don't support any extension for now on QEMU */
+ *val = 0x00;
+ return RISCV_EXCP_NONE;
+}
+
+static bool test_neorv32_mvendorid(RISCVCPU *cpu)
+{
+ return cpu->cfg.mvendorid == NEORV32_VENDOR_ID;
+}
+
+const RISCVCSR neorv32_csr_list[] = {
+ {
+ .csrno = CSR_MXISA,
+ .insertion_test = test_neorv32_mvendorid,
+ .csr_ops = { "neorv32.xisa", smode, read_neorv32_xisa }
+ },
+ { }
+};
+
