On Mon, Jan 6, 2025 at 9:45 AM Alistair Francis <alistai...@gmail.com>
wrote:
> On Tue, Dec 31, 2024 at 1:28 PM <frank.ch...@sifive.com> wrote:
> >
> > From: Tommy Wu <tommy...@sifive.com>
> >
> > Because the RNMI interrupt trap handler address is implementation
> defined.
> > We add the 'rnmi-interrupt-vector' and 'rnmi-exception-vector' as the
> property
> > of the harts. It’s very easy for users to set the address based on their
> > expectation. This patch also adds the functionality to handle the RNMI
> signals.
> >
> > Signed-off-by: Frank Chang <frank.ch...@sifive.com>
> > Signed-off-by: Tommy Wu <tommy...@sifive.com>
> > Reviewed-by: Daniel Henrique Barboza <dbarb...@ventanamicro.com>
> > ---
> > hw/riscv/riscv_hart.c | 42 ++++++++++++++++-
> > include/hw/riscv/riscv_hart.h | 4 ++
> > target/riscv/cpu.c | 11 +++++
> > target/riscv/cpu.h | 3 ++
> > target/riscv/cpu_bits.h | 12 +++++
> > target/riscv/cpu_helper.c | 85 ++++++++++++++++++++++++++++++++---
> > 6 files changed, 151 insertions(+), 6 deletions(-)
> >
> > diff --git a/hw/riscv/riscv_hart.c b/hw/riscv/riscv_hart.c
> > index 0df454772f..c2781848ce 100644
> > --- a/hw/riscv/riscv_hart.c
> > +++ b/hw/riscv/riscv_hart.c
> > @@ -26,6 +26,7 @@
> > #include "target/riscv/cpu.h"
> > #include "hw/qdev-properties.h"
> > #include "hw/riscv/riscv_hart.h"
> > +#include "qemu/error-report.h"
> >
> > static const Property riscv_harts_props[] = {
> > DEFINE_PROP_UINT32("num-harts", RISCVHartArrayState, num_harts, 1),
> > @@ -33,7 +34,23 @@ static const Property riscv_harts_props[] = {
> > DEFINE_PROP_STRING("cpu-type", RISCVHartArrayState, cpu_type),
> > DEFINE_PROP_UINT64("resetvec", RISCVHartArrayState, resetvec,
> > DEFAULT_RSTVEC),
> > - DEFINE_PROP_END_OF_LIST(),
> > +
> > + /*
> > + * Smrnmi implementation-defined interrupt and exception trap
> handlers.
> > + *
> > + * When an RNMI interrupt is detected, the hart then enters M-mode
> and
> > + * jumps to the address defined by "rnmi-interrupt-vector".
> > + *
> > + * When the hart encounters an exception while executing in M-mode
> with
> > + * the mnstatus.NMIE bit clear, the hart then jumps to the address
> > + * defined by "rnmi-exception-vector".
> > + */
> > + DEFINE_PROP_ARRAY("rnmi-interrupt-vector", RISCVHartArrayState,
> > + num_rnmi_irqvec, rnmi_irqvec, qdev_prop_uint64,
> > + uint64_t),
> > + DEFINE_PROP_ARRAY("rnmi-exception-vector", RISCVHartArrayState,
> > + num_rnmi_excpvec, rnmi_excpvec, qdev_prop_uint64,
> > + uint64_t),
> > };
> >
> > static void riscv_harts_cpu_reset(void *opaque)
> > @@ -47,6 +64,29 @@ static bool riscv_hart_realize(RISCVHartArrayState
> *s, int idx,
> > {
> > object_initialize_child(OBJECT(s), "harts[*]", &s->harts[idx],
> cpu_type);
> > qdev_prop_set_uint64(DEVICE(&s->harts[idx]), "resetvec",
> s->resetvec);
> > +
> > + if (s->harts[idx].cfg.ext_smrnmi) {
> > + if (idx < s->num_rnmi_irqvec) {
> > + qdev_prop_set_uint64(DEVICE(&s->harts[idx]),
> > + "rnmi-interrupt-vector",
> s->rnmi_irqvec[idx]);
> > + }
> > +
> > + if (idx < s->num_rnmi_excpvec) {
> > + qdev_prop_set_uint64(DEVICE(&s->harts[idx]),
> > + "rnmi-exception-vector",
> s->rnmi_excpvec[idx]);
> > + }
> > + } else {
> > + if (s->num_rnmi_irqvec > 0) {
> > + warn_report_once("rnmi-interrupt-vector property is ignored
> "
> > + "because Smrnmi extension is not
> enabled.");
> > + }
> > +
> > + if (s->num_rnmi_excpvec > 0) {
> > + warn_report_once("rnmi-exception-vector property is ignored
> "
> > + "because Smrnmi extension is not
> enabled.");
> > + }
> > + }
> > +
> > s->harts[idx].env.mhartid = s->hartid_base + idx;
> > qemu_register_reset(riscv_harts_cpu_reset, &s->harts[idx]);
> > return qdev_realize(DEVICE(&s->harts[idx]), NULL, errp);
> > diff --git a/include/hw/riscv/riscv_hart.h
> b/include/hw/riscv/riscv_hart.h
> > index 912b4a2682..a6ed73a195 100644
> > --- a/include/hw/riscv/riscv_hart.h
> > +++ b/include/hw/riscv/riscv_hart.h
> > @@ -38,6 +38,10 @@ struct RISCVHartArrayState {
> > uint32_t hartid_base;
> > char *cpu_type;
> > uint64_t resetvec;
> > + uint32_t num_rnmi_irqvec;
> > + uint64_t *rnmi_irqvec;
> > + uint32_t num_rnmi_excpvec;
> > + uint64_t *rnmi_excpvec;
> > RISCVCPU *harts;
> > };
> >
> > diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> > index c5d5c2f7df..6c46a2f076 100644
> > --- a/target/riscv/cpu.c
> > +++ b/target/riscv/cpu.c
> > @@ -1412,6 +1412,11 @@ static void riscv_cpu_set_irq(void *opaque, int
> irq, int level)
> > g_assert_not_reached();
> > }
> > }
> > +
> > +static void riscv_cpu_set_nmi(void *opaque, int irq, int level)
> > +{
> > + riscv_cpu_set_rnmi(RISCV_CPU(opaque), irq, level);
> > +}
> > #endif /* CONFIG_USER_ONLY */
> >
> > static bool riscv_cpu_is_dynamic(Object *cpu_obj)
> > @@ -1435,6 +1440,8 @@ static void riscv_cpu_init(Object *obj)
> > #ifndef CONFIG_USER_ONLY
> > qdev_init_gpio_in(DEVICE(obj), riscv_cpu_set_irq,
> > IRQ_LOCAL_MAX + IRQ_LOCAL_GUEST_MAX);
> > + qdev_init_gpio_in_named(DEVICE(cpu), riscv_cpu_set_nmi,
> > + "riscv.cpu.rnmi", RNMI_MAX);
> > #endif /* CONFIG_USER_ONLY */
> >
> > general_user_opts = g_hash_table_new(g_str_hash, g_str_equal);
> > @@ -2789,6 +2796,10 @@ static const Property riscv_cpu_properties[] = {
> >
> > #ifndef CONFIG_USER_ONLY
> > DEFINE_PROP_UINT64("resetvec", RISCVCPU, env.resetvec,
> DEFAULT_RSTVEC),
> > + DEFINE_PROP_UINT64("rnmi-interrupt-vector", RISCVCPU,
> env.rnmi_irqvec,
> > + DEFAULT_RNMI_IRQVEC),
> > + DEFINE_PROP_UINT64("rnmi-exception-vector", RISCVCPU,
> env.rnmi_excpvec,
> > + DEFAULT_RNMI_EXCPVEC),
> > #endif
> >
> > DEFINE_PROP_BOOL("short-isa-string", RISCVCPU,
> cfg.short_isa_string, false),
> > diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> > index a2cb471b3c..8dc5b4d002 100644
> > --- a/target/riscv/cpu.h
> > +++ b/target/riscv/cpu.h
> > @@ -493,6 +493,8 @@ struct CPUArchState {
> > target_ulong mncause; /* mncause without bit XLEN-1 set to 1 */
> > target_ulong mnstatus;
> > target_ulong rnmip;
> > + uint64_t rnmi_irqvec;
> > + uint64_t rnmi_excpvec;
> > };
> >
> > /*
> > @@ -591,6 +593,7 @@ void riscv_cpu_swap_hypervisor_regs(CPURISCVState
> *env);
> > int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint64_t interrupts);
> > uint64_t riscv_cpu_update_mip(CPURISCVState *env, uint64_t mask,
> > uint64_t value);
> > +void riscv_cpu_set_rnmi(RISCVCPU *cpu, uint32_t irq, bool level);
> > void riscv_cpu_interrupt(CPURISCVState *env);
> > #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip
> value */
> > void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(void *),
> > diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
> > index 9e9637263d..17787fd693 100644
> > --- a/target/riscv/cpu_bits.h
> > +++ b/target/riscv/cpu_bits.h
> > @@ -680,6 +680,12 @@ typedef enum {
> > /* Default Reset Vector address */
> > #define DEFAULT_RSTVEC 0x1000
> >
> > +/* Default RNMI Interrupt Vector address */
> > +#define DEFAULT_RNMI_IRQVEC 0x0
> > +
> > +/* Default RNMI Exception Vector address */
> > +#define DEFAULT_RNMI_EXCPVEC 0x0
> > +
> > /* Exception causes */
> > typedef enum RISCVException {
> > RISCV_EXCP_NONE = -1, /* sentinel value */
> > @@ -734,6 +740,9 @@ typedef enum RISCVException {
> > /* -1 is due to bit zero of hgeip and hgeie being ROZ. */
> > #define IRQ_LOCAL_GUEST_MAX (TARGET_LONG_BITS - 1)
> >
> > +/* RNMI causes */
> > +#define RNMI_MAX 16
> > +
> > /* mip masks */
> > #define MIP_USIP (1 << IRQ_U_SOFT)
> > #define MIP_SSIP (1 << IRQ_S_SOFT)
> > @@ -972,6 +981,9 @@ typedef enum RISCVException {
> > #define MHPMEVENT_IDX_MASK 0xFFFFF
> > #define MHPMEVENT_SSCOF_RESVD 16
> >
> > +/* RISC-V-specific interrupt pending bits. */
> > +#define CPU_INTERRUPT_RNMI CPU_INTERRUPT_TGT_EXT_0
> > +
> > /* JVT CSR bits */
> > #define JVT_MODE 0x3F
> > #define JVT_BASE (~0x3F)
> > diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
> > index 750c0537ca..e5ffbbbd83 100644
> > --- a/target/riscv/cpu_helper.c
> > +++ b/target/riscv/cpu_helper.c
> > @@ -505,6 +505,18 @@ static int
> riscv_cpu_local_irq_pending(CPURISCVState *env)
> > uint64_t vsbits, irq_delegated;
> > int virq;
> >
> > + /* Priority: RNMI > Other interrupt. */
> > + if (riscv_cpu_cfg(env)->ext_smrnmi) {
> > + /* If mnstatus.NMIE == 0, all interrupts are disabled. */
> > + if (!get_field(env->mnstatus, MNSTATUS_NMIE)) {
> > + return RISCV_EXCP_NONE;
> > + }
> > +
> > + if (env->rnmip) {
> > + return ctz64(env->rnmip); /* since non-zero */
> > + }
> > + }
> > +
> > /* Determine interrupt enable state of all privilege modes */
> > if (env->virt_enabled) {
> > mie = 1;
> > @@ -567,7 +579,9 @@ static int riscv_cpu_local_irq_pending(CPURISCVState
> *env)
> >
> > bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
> > {
> > - if (interrupt_request & CPU_INTERRUPT_HARD) {
> > + uint32_t mask = CPU_INTERRUPT_HARD | CPU_INTERRUPT_RNMI;
> > +
> > + if (interrupt_request & mask) {
> > RISCVCPU *cpu = RISCV_CPU(cs);
> > CPURISCVState *env = &cpu->env;
> > int interruptno = riscv_cpu_local_irq_pending(env);
> > @@ -699,6 +713,30 @@ void riscv_cpu_set_geilen(CPURISCVState *env,
> target_ulong geilen)
> > env->geilen = geilen;
> > }
> >
> > +void riscv_cpu_set_rnmi(RISCVCPU *cpu, uint32_t irq, bool level)
> > +{
> > + CPURISCVState *env = &cpu->env;
> > + CPUState *cs = CPU(cpu);
> > + bool release_lock = false;
> > +
> > + if (!bql_locked()) {
> > + release_lock = true;
> > + bql_lock();
> > + }
> > +
> > + if (level) {
> > + env->rnmip |= 1 << irq;
> > + cpu_interrupt(cs, CPU_INTERRUPT_RNMI);
> > + } else {
> > + env->rnmip &= ~(1 << irq);
> > + cpu_reset_interrupt(cs, CPU_INTERRUPT_RNMI);
> > + }
> > +
> > + if (release_lock) {
> > + bql_unlock();
> > + }
> > +}
> > +
> > int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint64_t interrupts)
> > {
> > CPURISCVState *env = &cpu->env;
> > @@ -1849,6 +1887,7 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> > bool write_gva = false;
> > bool always_storeamo = (env->excp_uw2 & RISCV_UW2_ALWAYS_STORE_AMO);
> > uint64_t s;
> > + int mode;
> >
> > /*
> > * cs->exception is 32-bits wide unlike mcause which is XLEN-bits
> wide
> > @@ -1867,6 +1906,23 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> > target_ulong mtval2 = 0;
> > int sxlen = 0;
> > int mxlen = 0;
> > + bool nnmi_excep = false;
> > +
> > + if (cpu->cfg.ext_smrnmi && env->rnmip && async) {
> > + env->mnstatus = set_field(env->mnstatus, MNSTATUS_NMIE, false);
> > + env->mnstatus = set_field(env->mnstatus, MNSTATUS_MNPV,
> > + env->virt_enabled);
> > + env->mnstatus = set_field(env->mnstatus, MNSTATUS_MNPP,
> > + env->priv);
> > + env->mncause = cause | ((target_ulong)1U << (TARGET_LONG_BITS -
> 1));
>
> TARGET_LONG_BITS won't work if running a 32-bit CPU on a 64-bit built
> binary. You will need to look at MXL instead
>
> Alistair
>
Thanks, I've fixed it in the v12 patchset.
Regards,
Frank Chang
>
> > + env->mnepc = env->pc;
> > + env->pc = env->rnmi_irqvec;
> > +
> > + /* Trapping to M mode, virt is disabled */
> > + riscv_cpu_set_mode(env, PRV_M, false);
> > +
> > + return;
> > + }
> >
> > if (!async) {
> > /* set tval to badaddr for traps with address information */
> > @@ -1960,8 +2016,10 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> > __func__, env->mhartid, async, cause, env->pc, tval,
> > riscv_cpu_get_trap_name(cause, async));
> >
> > - if (env->priv <= PRV_S && cause < 64 &&
> > - (((deleg >> cause) & 1) || s_injected || vs_injected)) {
> > + mode = env->priv <= PRV_S && cause < 64 &&
> > + (((deleg >> cause) & 1) || s_injected || vs_injected) ? PRV_S :
> PRV_M;
> > +
> > + if (mode == PRV_S) {
> > /* handle the trap in S-mode */
> > /* save elp status */
> > if (cpu_get_fcfien(env)) {
> > @@ -2016,6 +2074,14 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> > ((async && (env->stvec & 3) == 1) ? cause * 4 : 0);
> > riscv_cpu_set_mode(env, PRV_S, virt);
> > } else {
> > + /*
> > + * If the hart encounters an exception while executing in M-mode
> > + * with the mnstatus.NMIE bit clear, the exception is an RNMI
> exception.
> > + */
> > + nnmi_excep = cpu->cfg.ext_smrnmi &&
> > + !get_field(env->mnstatus, MNSTATUS_NMIE) &&
> > + !async;
> > +
> > /* handle the trap in M-mode */
> > /* save elp status */
> > if (cpu_get_fcfien(env)) {
> > @@ -2049,8 +2115,17 @@ void riscv_cpu_do_interrupt(CPUState *cs)
> > env->mtval = tval;
> > env->mtval2 = mtval2;
> > env->mtinst = tinst;
> > - env->pc = (env->mtvec >> 2 << 2) +
> > - ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0);
> > +
> > + /*
> > + * For RNMI exception, program counter is set to the RNMI
> exception
> > + * trap handler address.
> > + */
> > + if (nnmi_excep) {
> > + env->pc = env->rnmi_excpvec;
> > + } else {
> > + env->pc = (env->mtvec >> 2 << 2) +
> > + ((async && (env->mtvec & 3) == 1) ? cause * 4 :
> 0);
> > + }
> > riscv_cpu_set_mode(env, PRV_M, virt);
> > }
> >
> > --
> > 2.34.1
> >
> >
>
