From 85553e7ca97dc35fccad8e24830c72111e110d32 Mon Sep 17 00:00:00 2001 From: "Edgar E. Iglesias" Date: Mon, 29 Aug 2011 23:07:40 +0200 Subject: [PATCH] mips: Add MT halting and waking of VPEs + some partial support for TC's. Signed-off-by: Edgar E. Iglesias --- target-mips/cpu.h | 51 +++++++++++++++++++++++++ target-mips/op_helper.c | 82 +++++++++++++++++++++++++++++++++++++++-- 2 files changed, 129 insertions(+), 4 deletions(-) diff --git a/target-mips/cpu.h b/target-mips/cpu.h index c5f70fa759..f6f16a34be 100644 --- a/target-mips/cpu.h +++ b/target-mips/cpu.h @@ -618,6 +618,14 @@ enum { /* Dummy exception for conditional stores. */ #define EXCP_SC 0x100 +/* + * This is an interrnally generated WAKE request line. + * It is driven by the CPU itself. Raised when the MT + * block wants to wake a VPE from an inactive state and + * cleared when VPE goes from active to inactive. + */ +#define CPU_INTERRUPT_WAKE CPU_INTERRUPT_TGT_INT_0 + int cpu_mips_exec(CPUMIPSState *s); CPUMIPSState *cpu_mips_init(const char *cpu_model); //~ uint32_t cpu_mips_get_clock (void); @@ -658,6 +666,37 @@ static inline void cpu_set_tls(CPUState *env, target_ulong newtls) env->tls_value = newtls; } +static inline int mips_vpe_active(CPUState *env) +{ + int active = 1; + + /* Check that the VPE is enabled. */ + if (!(env->mvp->CP0_MVPControl & (1 << CP0MVPCo_EVP))) { + active = 0; + } + /* Check that the VPE is actived. */ + if (!(env->CP0_VPEConf0 & (1 << CP0VPEC0_VPA))) { + active = 0; + } + + /* Now verify that there are active thread contexts in the VPE. + + This assumes the CPU model will internally reschedule threads + if the active one goes to sleep. If there are no threads available + the active one will be in a sleeping state, and we can turn off + the entire VPE. */ + if (!(env->active_tc.CP0_TCStatus & (1 << CP0TCSt_A))) { + /* TC is not activated. */ + active = 0; + } + if (env->active_tc.CP0_TCHalt & 1) { + /* TC is in halt state. */ + active = 0; + } + + return active; +} + static inline int cpu_has_work(CPUState *env) { int has_work = 0; @@ -670,6 +709,18 @@ static inline int cpu_has_work(CPUState *env) has_work = 1; } + /* MIPS-MT has the ability to halt the CPU. */ + if (env->CP0_Config3 & (1 << CP0C3_MT)) { + /* The QEMU model will issue an _WAKE request whenever the CPUs + should be woken up. */ + if (env->interrupt_request & CPU_INTERRUPT_WAKE) { + has_work = 1; + } + + if (!mips_vpe_active(env)) { + has_work = 0; + } + } return has_work; } diff --git a/target-mips/op_helper.c b/target-mips/op_helper.c index 03a4f1839a..96e40c6018 100644 --- a/target-mips/op_helper.c +++ b/target-mips/op_helper.c @@ -749,6 +749,46 @@ void helper_sdm (target_ulong addr, target_ulong reglist, uint32_t mem_idx) #endif #ifndef CONFIG_USER_ONLY +/* SMP helpers. */ +static int mips_vpe_is_wfi(CPUState *c) +{ + /* If the VPE is halted but otherwise active, it means it's waiting for + an interrupt. */ + return c->halted && mips_vpe_active(c); +} + +static inline void mips_vpe_wake(CPUState *c) +{ + /* Dont set ->halted = 0 directly, let it be done via cpu_has_work + because there might be other conditions that state that c should + be sleeping. */ + cpu_interrupt(c, CPU_INTERRUPT_WAKE); +} + +static inline void mips_vpe_sleep(CPUState *c) +{ + /* The VPE was shut off, really go to bed. + Reset any old _WAKE requests. */ + c->halted = 1; + cpu_reset_interrupt(c, CPU_INTERRUPT_WAKE); +} + +static inline void mips_tc_wake(CPUState *c, int tc) +{ + /* FIXME: TC reschedule. */ + if (mips_vpe_active(c) && !mips_vpe_is_wfi(c)) { + mips_vpe_wake(c); + } +} + +static inline void mips_tc_sleep(CPUState *c, int tc) +{ + /* FIXME: TC reschedule. */ + if (!mips_vpe_active(c)) { + mips_vpe_sleep(c); + } +} + /* tc should point to an int with the value of the global TC index. This function will transform it into a local index within the returned CPUState. @@ -1340,6 +1380,11 @@ void helper_mtc0_tchalt (target_ulong arg1) env->active_tc.CP0_TCHalt = arg1 & 0x1; // TODO: Halt TC / Restart (if allocated+active) TC. + if (env->active_tc.CP0_TCHalt & 1) { + mips_tc_sleep(env, env->current_tc); + } else { + mips_tc_wake(env, env->current_tc); + } } void helper_mttc0_tchalt (target_ulong arg1) @@ -1353,6 +1398,12 @@ void helper_mttc0_tchalt (target_ulong arg1) other->active_tc.CP0_TCHalt = arg1; else other->tcs[other_tc].CP0_TCHalt = arg1; + + if (arg1 & 1) { + mips_tc_sleep(other, other_tc); + } else { + mips_tc_wake(other, other_tc); + } } void helper_mtc0_tccontext (target_ulong arg1) @@ -1858,14 +1909,36 @@ target_ulong helper_emt(void) target_ulong helper_dvpe(void) { - // TODO - return 0; + CPUState *other_cpu = first_cpu; + target_ulong prev = env->mvp->CP0_MVPControl; + + do { + /* Turn off all VPEs except the one executing the dvpe. */ + if (other_cpu != env) { + other_cpu->mvp->CP0_MVPControl &= ~(1 << CP0MVPCo_EVP); + mips_vpe_sleep(other_cpu); + } + other_cpu = other_cpu->next_cpu; + } while (other_cpu); + return prev; } target_ulong helper_evpe(void) { - // TODO - return 0; + CPUState *other_cpu = first_cpu; + target_ulong prev = env->mvp->CP0_MVPControl; + + do { + if (other_cpu != env + /* If the VPE is WFI, dont distrub it's sleep. */ + && !mips_vpe_is_wfi(other_cpu)) { + /* Enable the VPE. */ + other_cpu->mvp->CP0_MVPControl |= (1 << CP0MVPCo_EVP); + mips_vpe_wake(other_cpu); /* And wake it up. */ + } + other_cpu = other_cpu->next_cpu; + } while (other_cpu); + return prev; } #endif /* !CONFIG_USER_ONLY */ @@ -2213,6 +2286,7 @@ void helper_pmon (int function) void helper_wait (void) { env->halted = 1; + cpu_reset_interrupt(env, CPU_INTERRUPT_WAKE); helper_raise_exception(EXCP_HLT); } -- 2.34.1