On Wed, Apr 25, 2018 at 5:02 PM Michael Clark <m...@sifive.com> wrote:
> Change the API of riscv_set_local_interrupt to take a > write mask and value to allow setting and clearing of > multiple local interrupts atomically in a single call. > Rename the new function to riscv_cpu_update_mip. > Cc: Sagar Karandikar <sag...@eecs.berkeley.edu> > Cc: Bastian Koppelmann <kbast...@mail.uni-paderborn.de> > Cc: Palmer Dabbelt <pal...@sifive.com> > Cc: Alistair Francis <alistair.fran...@wdc.com> > Signed-off-by: Michael Clark <m...@sifive.com> > --- > hw/riscv/sifive_clint.c | 8 ++++---- > hw/riscv/sifive_plic.c | 4 ++-- > target/riscv/cpu.h | 8 +++----- > target/riscv/op_helper.c | 23 ++++++++++++++--------- > 4 files changed, 23 insertions(+), 20 deletions(-) > diff --git a/hw/riscv/sifive_clint.c b/hw/riscv/sifive_clint.c > index 7cc606e..909929b 100644 > --- a/hw/riscv/sifive_clint.c > +++ b/hw/riscv/sifive_clint.c > @@ -47,12 +47,12 @@ static void sifive_clint_write_timecmp(RISCVCPU *cpu, uint64_t value) > if (cpu->env.timecmp <= rtc_r) { > /* if we're setting an MTIMECMP value in the "past", > immediately raise the timer interrupt */ > - riscv_set_local_interrupt(cpu, MIP_MTIP, 1); > + riscv_cpu_update_mip(cpu, MIP_MTIP, -1); Using -1 for a mask seems nasty and confusing. There is a QEMU macro MAKE_64BIT_MASK() that seems like a great fit for this. Alistair > return; > } > /* otherwise, set up the future timer interrupt */ > - riscv_set_local_interrupt(cpu, MIP_MTIP, 0); > + riscv_cpu_update_mip(cpu, MIP_MTIP, 0); > diff = cpu->env.timecmp - rtc_r; > /* back to ns (note args switched in muldiv64) */ > next = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + > @@ -67,7 +67,7 @@ static void sifive_clint_write_timecmp(RISCVCPU *cpu, uint64_t value) > static void sifive_clint_timer_cb(void *opaque) > { > RISCVCPU *cpu = opaque; > - riscv_set_local_interrupt(cpu, MIP_MTIP, 1); > + riscv_cpu_update_mip(cpu, MIP_MTIP, -1); > } > /* CPU wants to read rtc or timecmp register */ > @@ -132,7 +132,7 @@ static void sifive_clint_write(void *opaque, hwaddr addr, uint64_t value, > if (!env) { > error_report("clint: invalid timecmp hartid: %zu", hartid); > } else if ((addr & 0x3) == 0) { > - riscv_set_local_interrupt(RISCV_CPU(cpu), MIP_MSIP, value != 0); > + riscv_cpu_update_mip(RISCV_CPU(cpu), MIP_MSIP, -!!value); > } else { > error_report("clint: invalid sip write: %08x", (uint32_t)addr); > } > diff --git a/hw/riscv/sifive_plic.c b/hw/riscv/sifive_plic.c > index 04e39e4..fa0298d 100644 > --- a/hw/riscv/sifive_plic.c > +++ b/hw/riscv/sifive_plic.c > @@ -141,10 +141,10 @@ static void sifive_plic_update(SiFivePLICState *plic) > int level = sifive_plic_irqs_pending(plic, addrid); > switch (mode) { > case PLICMode_M: > - riscv_set_local_interrupt(RISCV_CPU(cpu), MIP_MEIP, level); > + riscv_cpu_update_mip(RISCV_CPU(cpu), MIP_MEIP, -!!level); > break; > case PLICMode_S: > - riscv_set_local_interrupt(RISCV_CPU(cpu), MIP_SEIP, level); > + riscv_cpu_update_mip(RISCV_CPU(cpu), MIP_SEIP, -!!level); > break; > default: > break; > diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h > index e0608e6..5ac1482 100644 > --- a/target/riscv/cpu.h > +++ b/target/riscv/cpu.h > @@ -247,7 +247,6 @@ void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr, > uintptr_t retaddr); > int riscv_cpu_handle_mmu_fault(CPUState *cpu, vaddr address, int size, > int rw, int mmu_idx); > - > char *riscv_isa_string(RISCVCPU *cpu); > void riscv_cpu_list(FILE *f, fprintf_function cpu_fprintf); > @@ -256,6 +255,9 @@ void riscv_cpu_list(FILE *f, fprintf_function cpu_fprintf); > #define cpu_list riscv_cpu_list > #define cpu_mmu_index riscv_cpu_mmu_index > +#ifndef CONFIG_USER_ONLY > +uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value); > +#endif > void riscv_set_mode(CPURISCVState *env, target_ulong newpriv); > void riscv_translate_init(void); > @@ -286,10 +288,6 @@ void csr_write_helper(CPURISCVState *env, target_ulong val_to_write, > target_ulong csrno); > target_ulong csr_read_helper(CPURISCVState *env, target_ulong csrno); > -#ifndef CONFIG_USER_ONLY > -void riscv_set_local_interrupt(RISCVCPU *cpu, target_ulong mask, int value); > -#endif > - > #include "exec/cpu-all.h" > #endif /* RISCV_CPU_H */ > diff --git a/target/riscv/op_helper.c b/target/riscv/op_helper.c > index 7d3f1ee..2a7f045 100644 > --- a/target/riscv/op_helper.c > +++ b/target/riscv/op_helper.c > @@ -171,10 +171,8 @@ void csr_write_helper(CPURISCVState *env, target_ulong val_to_write, > */ > qemu_mutex_lock_iothread(); > RISCVCPU *cpu = riscv_env_get_cpu(env); > - riscv_set_local_interrupt(cpu, MIP_SSIP, > - (val_to_write & MIP_SSIP) != 0); > - riscv_set_local_interrupt(cpu, MIP_STIP, > - (val_to_write & MIP_STIP) != 0); > + riscv_cpu_update_mip(cpu, MIP_SSIP | MIP_STIP, > + (val_to_write & (MIP_SSIP | MIP_STIP))); > /* > * csrs, csrc on mip.SEIP is not decomposable into separate read and > * write steps, so a different implementation is needed > @@ -643,16 +641,23 @@ target_ulong helper_csrrc(CPURISCVState *env, target_ulong src, > #ifndef CONFIG_USER_ONLY > /* iothread_mutex must be held */ > -void riscv_set_local_interrupt(RISCVCPU *cpu, target_ulong mask, int value) > +uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value) > { > - target_ulong old_mip = cpu->env.mip; > - cpu->env.mip = (old_mip & ~mask) | (value ? mask : 0); > + CPURISCVState *env = &cpu->env; > + uint32_t old_mip, new_mip; > - if (cpu->env.mip && !old_mip) { > + do { > + old_mip = atomic_read(&env->mip); > + new_mip = (old_mip & ~mask) | (value & mask); > + } while (atomic_cmpxchg(&env->mip, old_mip, new_mip) != old_mip); > + > + if (new_mip && !old_mip) { > cpu_interrupt(CPU(cpu), CPU_INTERRUPT_HARD); > - } else if (!cpu->env.mip && old_mip) { > + } else if (!new_mip && old_mip) { > cpu_reset_interrupt(CPU(cpu), CPU_INTERRUPT_HARD); > } > + > + return old_mip; > } > void riscv_set_mode(CPURISCVState *env, target_ulong newpriv) > -- > 2.7.0