From a1863ad368d32b53153bf417a83f01c85bb9d82c Mon Sep 17 00:00:00 2001 From: Daniel Henrique Barboza Date: Thu, 6 Jul 2023 07:17:22 -0300 Subject: [PATCH] target/riscv/cpu.c: restrict 'mimpid' value Following the same logic used with 'mvendorid' let's also restrict 'mimpid' for named CPUs. Generic CPUs keep setting the value freely. Note that we're getting rid of the default RISCV_CPU_MARCHID value. The reason is that this is not a good default since it's dynamic, changing with with every QEMU version, regardless of whether the actual implementation of the CPU changed from one QEMU version to the other. Named CPU should set it to a meaningful value instead and generic CPUs can set whatever they want. This is the error thrown for an invalid 'mimpid' value for the veyron-v1 CPU: $ ./qemu-system-riscv64 -M virt -nographic -cpu veyron-v1,mimpid=2 qemu-system-riscv64: can't apply global veyron-v1-riscv-cpu.mimpid=2: Unable to change veyron-v1-riscv-cpu mimpid (0x111) Signed-off-by: Daniel Henrique Barboza Reviewed-by: Andrew Jones Reviewed-by: Alistair Francis Message-Id: <20230706101738.460804-5-dbarboza@ventanamicro.com> Signed-off-by: Alistair Francis --- target/riscv/cpu.c | 34 ++++++++++++++++++++++++++++++++-- 1 file changed, 32 insertions(+), 2 deletions(-) diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c index a778241d9f..477f8f8f97 100644 --- a/target/riscv/cpu.c +++ b/target/riscv/cpu.c @@ -43,7 +43,6 @@ #define RISCV_CPU_MARCHID ((QEMU_VERSION_MAJOR << 16) | \ (QEMU_VERSION_MINOR << 8) | \ (QEMU_VERSION_MICRO)) -#define RISCV_CPU_MIMPID RISCV_CPU_MARCHID static const char riscv_single_letter_exts[] = "IEMAFDQCPVH"; @@ -1813,7 +1812,6 @@ static Property riscv_cpu_properties[] = { DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true), DEFINE_PROP_UINT64("marchid", RISCVCPU, cfg.marchid, RISCV_CPU_MARCHID), - DEFINE_PROP_UINT64("mimpid", RISCVCPU, cfg.mimpid, RISCV_CPU_MIMPID), #ifndef CONFIG_USER_ONLY DEFINE_PROP_UINT64("resetvec", RISCVCPU, env.resetvec, DEFAULT_RSTVEC), @@ -1932,6 +1930,35 @@ static void cpu_get_mvendorid(Object *obj, Visitor *v, const char *name, visit_type_bool(v, name, &value, errp); } +static void cpu_set_mimpid(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + bool dynamic_cpu = riscv_cpu_is_dynamic(obj); + RISCVCPU *cpu = RISCV_CPU(obj); + uint64_t prev_val = cpu->cfg.mimpid; + uint64_t value; + + if (!visit_type_uint64(v, name, &value, errp)) { + return; + } + + if (!dynamic_cpu && prev_val != value) { + error_setg(errp, "Unable to change %s mimpid (0x%" PRIu64 ")", + object_get_typename(obj), prev_val); + return; + } + + cpu->cfg.mimpid = value; +} + +static void cpu_get_mimpid(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + bool value = RISCV_CPU(obj)->cfg.mimpid; + + visit_type_bool(v, name, &value, errp); +} + static void riscv_cpu_class_init(ObjectClass *c, void *data) { RISCVCPUClass *mcc = RISCV_CPU_CLASS(c); @@ -1966,6 +1993,9 @@ static void riscv_cpu_class_init(ObjectClass *c, void *data) object_class_property_add(c, "mvendorid", "uint32", cpu_get_mvendorid, cpu_set_mvendorid, NULL, NULL); + object_class_property_add(c, "mimpid", "uint64", cpu_get_mimpid, + cpu_set_mimpid, NULL, NULL); + device_class_set_props(dc, riscv_cpu_properties); }