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From: Fabiano Rosas <farosas@linux.ibm.com>
To: qemu-devel@nongnu.org
Cc: richard.henderson@linaro.org, danielhb413@gmail.com,
	qemu-ppc@nongnu.org, clg@kaod.org, david@gibson.dropbear.id.au
Subject: [PATCH 3/8] target/ppc: Introduce powerpc_excp_40x
Date: Mon, 10 Jan 2022 15:15:41 -0300	[thread overview]
Message-ID: <20220110181546.4131853-4-farosas@linux.ibm.com> (raw)
In-Reply-To: <20220110181546.4131853-1-farosas@linux.ibm.com>

Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
---
I copied powerpc_excp_legacy verbatim in this commit so the next
one has a clean diff. We can squash both commits before merging.
---
 target/ppc/excp_helper.c | 474 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 474 insertions(+)

diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
index bc646c67a0..12ab5e1b34 100644
--- a/target/ppc/excp_helper.c
+++ b/target/ppc/excp_helper.c
@@ -392,6 +392,477 @@ static void powerpc_set_excp_state(PowerPCCPU *cpu,
     check_tlb_flush(env, false);
 }
 
+static void powerpc_excp_40x(PowerPCCPU *cpu, int excp)
+{
+    CPUState *cs = CPU(cpu);
+    CPUPPCState *env = &cpu->env;
+    int excp_model = env->excp_model;
+    target_ulong msr, new_msr, vector;
+    int srr0, srr1, lev = -1;
+
+    if (excp <= POWERPC_EXCP_NONE || excp >= POWERPC_EXCP_NB) {
+        cpu_abort(cs, "Invalid PowerPC exception %d. Aborting\n", excp);
+    }
+
+    qemu_log_mask(CPU_LOG_INT, "Raise exception at " TARGET_FMT_lx
+                  " => %s (%d) error=%02x\n", env->nip, powerpc_excp_name(excp),
+                  excp, env->error_code);
+
+    /* new srr1 value excluding must-be-zero bits */
+    if (excp_model == POWERPC_EXCP_BOOKE) {
+        msr = env->msr;
+    } else {
+        msr = env->msr & ~0x783f0000ULL;
+    }
+
+    /*
+     * new interrupt handler msr preserves existing HV and ME unless
+     * explicitly overriden
+     */
+    new_msr = env->msr & (((target_ulong)1 << MSR_ME) | MSR_HVB);
+
+    /* target registers */
+    srr0 = SPR_SRR0;
+    srr1 = SPR_SRR1;
+
+    /*
+     * check for special resume at 0x100 from doze/nap/sleep/winkle on
+     * P7/P8/P9
+     */
+    if (env->resume_as_sreset) {
+        excp = powerpc_reset_wakeup(cs, env, excp, &msr);
+    }
+
+    /*
+     * Hypervisor emulation assistance interrupt only exists on server
+     * arch 2.05 server or later. We also don't want to generate it if
+     * we don't have HVB in msr_mask (PAPR mode).
+     */
+    if (excp == POWERPC_EXCP_HV_EMU
+#if defined(TARGET_PPC64)
+        && !(mmu_is_64bit(env->mmu_model) && (env->msr_mask & MSR_HVB))
+#endif /* defined(TARGET_PPC64) */
+
+    ) {
+        excp = POWERPC_EXCP_PROGRAM;
+    }
+
+#ifdef TARGET_PPC64
+    /*
+     * SPEU and VPU share the same IVOR but they exist in different
+     * processors. SPEU is e500v1/2 only and VPU is e6500 only.
+     */
+    if (excp_model == POWERPC_EXCP_BOOKE && excp == POWERPC_EXCP_VPU) {
+        excp = POWERPC_EXCP_SPEU;
+    }
+#endif
+
+    vector = env->excp_vectors[excp];
+    if (vector == (target_ulong)-1ULL) {
+        cpu_abort(cs, "Raised an exception without defined vector %d\n",
+                  excp);
+    }
+
+    vector |= env->excp_prefix;
+
+    switch (excp) {
+    case POWERPC_EXCP_CRITICAL:    /* Critical input                         */
+        switch (excp_model) {
+        case POWERPC_EXCP_40x:
+            srr0 = SPR_40x_SRR2;
+            srr1 = SPR_40x_SRR3;
+            break;
+        case POWERPC_EXCP_BOOKE:
+            srr0 = SPR_BOOKE_CSRR0;
+            srr1 = SPR_BOOKE_CSRR1;
+            break;
+        case POWERPC_EXCP_G2:
+            break;
+        default:
+            goto excp_invalid;
+        }
+        break;
+    case POWERPC_EXCP_MCHECK:    /* Machine check exception                  */
+        if (msr_me == 0) {
+            /*
+             * Machine check exception is not enabled.  Enter
+             * checkstop state.
+             */
+            fprintf(stderr, "Machine check while not allowed. "
+                    "Entering checkstop state\n");
+            if (qemu_log_separate()) {
+                qemu_log("Machine check while not allowed. "
+                        "Entering checkstop state\n");
+            }
+            cs->halted = 1;
+            cpu_interrupt_exittb(cs);
+        }
+        if (env->msr_mask & MSR_HVB) {
+            /*
+             * ISA specifies HV, but can be delivered to guest with HV
+             * clear (e.g., see FWNMI in PAPR).
+             */
+            new_msr |= (target_ulong)MSR_HVB;
+        }
+
+        /* machine check exceptions don't have ME set */
+        new_msr &= ~((target_ulong)1 << MSR_ME);
+
+        /* XXX: should also have something loaded in DAR / DSISR */
+        switch (excp_model) {
+        case POWERPC_EXCP_40x:
+            srr0 = SPR_40x_SRR2;
+            srr1 = SPR_40x_SRR3;
+            break;
+        case POWERPC_EXCP_BOOKE:
+            /* FIXME: choose one or the other based on CPU type */
+            srr0 = SPR_BOOKE_MCSRR0;
+            srr1 = SPR_BOOKE_MCSRR1;
+
+            env->spr[SPR_BOOKE_CSRR0] = env->nip;
+            env->spr[SPR_BOOKE_CSRR1] = msr;
+            break;
+        default:
+            break;
+        }
+        break;
+    case POWERPC_EXCP_DSI:       /* Data storage exception                   */
+        trace_ppc_excp_dsi(env->spr[SPR_DSISR], env->spr[SPR_DAR]);
+        break;
+    case POWERPC_EXCP_ISI:       /* Instruction storage exception            */
+        trace_ppc_excp_isi(msr, env->nip);
+        msr |= env->error_code;
+        break;
+    case POWERPC_EXCP_EXTERNAL:  /* External input                           */
+    {
+        bool lpes0;
+
+        cs = CPU(cpu);
+
+        /*
+         * Exception targeting modifiers
+         *
+         * LPES0 is supported on POWER7/8/9
+         * LPES1 is not supported (old iSeries mode)
+         *
+         * On anything else, we behave as if LPES0 is 1
+         * (externals don't alter MSR:HV)
+         */
+#if defined(TARGET_PPC64)
+        if (excp_model == POWERPC_EXCP_POWER7 ||
+            excp_model == POWERPC_EXCP_POWER8 ||
+            excp_model == POWERPC_EXCP_POWER9 ||
+            excp_model == POWERPC_EXCP_POWER10) {
+            lpes0 = !!(env->spr[SPR_LPCR] & LPCR_LPES0);
+        } else
+#endif /* defined(TARGET_PPC64) */
+        {
+            lpes0 = true;
+        }
+
+        if (!lpes0) {
+            new_msr |= (target_ulong)MSR_HVB;
+            new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
+            srr0 = SPR_HSRR0;
+            srr1 = SPR_HSRR1;
+        }
+        if (env->mpic_proxy) {
+            /* IACK the IRQ on delivery */
+            env->spr[SPR_BOOKE_EPR] = ldl_phys(cs->as, env->mpic_iack);
+        }
+        break;
+    }
+    case POWERPC_EXCP_ALIGN:     /* Alignment exception                      */
+        /* Get rS/rD and rA from faulting opcode */
+        /*
+         * Note: the opcode fields will not be set properly for a
+         * direct store load/store, but nobody cares as nobody
+         * actually uses direct store segments.
+         */
+        env->spr[SPR_DSISR] |= (env->error_code & 0x03FF0000) >> 16;
+        break;
+    case POWERPC_EXCP_PROGRAM:   /* Program exception                        */
+        switch (env->error_code & ~0xF) {
+        case POWERPC_EXCP_FP:
+            if ((msr_fe0 == 0 && msr_fe1 == 0) || msr_fp == 0) {
+                trace_ppc_excp_fp_ignore();
+                cs->exception_index = POWERPC_EXCP_NONE;
+                env->error_code = 0;
+                return;
+            }
+
+            /*
+             * FP exceptions always have NIP pointing to the faulting
+             * instruction, so always use store_next and claim we are
+             * precise in the MSR.
+             */
+            msr |= 0x00100000;
+            env->spr[SPR_BOOKE_ESR] = ESR_FP;
+            break;
+        case POWERPC_EXCP_INVAL:
+            trace_ppc_excp_inval(env->nip);
+            msr |= 0x00080000;
+            env->spr[SPR_BOOKE_ESR] = ESR_PIL;
+            break;
+        case POWERPC_EXCP_PRIV:
+            msr |= 0x00040000;
+            env->spr[SPR_BOOKE_ESR] = ESR_PPR;
+            break;
+        case POWERPC_EXCP_TRAP:
+            msr |= 0x00020000;
+            env->spr[SPR_BOOKE_ESR] = ESR_PTR;
+            break;
+        default:
+            /* Should never occur */
+            cpu_abort(cs, "Invalid program exception %d. Aborting\n",
+                      env->error_code);
+            break;
+        }
+        break;
+    case POWERPC_EXCP_SYSCALL:   /* System call exception                    */
+        lev = env->error_code;
+
+        if ((lev == 1) && cpu->vhyp) {
+            dump_hcall(env);
+        } else {
+            dump_syscall(env);
+        }
+
+        /*
+         * We need to correct the NIP which in this case is supposed
+         * to point to the next instruction
+         */
+        env->nip += 4;
+
+        /* "PAPR mode" built-in hypercall emulation */
+        if ((lev == 1) && cpu->vhyp) {
+            PPCVirtualHypervisorClass *vhc =
+                PPC_VIRTUAL_HYPERVISOR_GET_CLASS(cpu->vhyp);
+            vhc->hypercall(cpu->vhyp, cpu);
+            return;
+        }
+        if (lev == 1) {
+            new_msr |= (target_ulong)MSR_HVB;
+        }
+        break;
+    case POWERPC_EXCP_SYSCALL_VECTORED: /* scv exception                     */
+        lev = env->error_code;
+        dump_syscall(env);
+        env->nip += 4;
+        new_msr |= env->msr & ((target_ulong)1 << MSR_EE);
+        new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
+
+        vector += lev * 0x20;
+
+        env->lr = env->nip;
+        env->ctr = msr;
+        break;
+    case POWERPC_EXCP_FPU:       /* Floating-point unavailable exception     */
+    case POWERPC_EXCP_APU:       /* Auxiliary processor unavailable          */
+    case POWERPC_EXCP_DECR:      /* Decrementer exception                    */
+        break;
+    case POWERPC_EXCP_FIT:       /* Fixed-interval timer interrupt           */
+        /* FIT on 4xx */
+        trace_ppc_excp_print("FIT");
+        break;
+    case POWERPC_EXCP_WDT:       /* Watchdog timer interrupt                 */
+        trace_ppc_excp_print("WDT");
+        switch (excp_model) {
+        case POWERPC_EXCP_BOOKE:
+            srr0 = SPR_BOOKE_CSRR0;
+            srr1 = SPR_BOOKE_CSRR1;
+            break;
+        default:
+            break;
+        }
+        break;
+    case POWERPC_EXCP_DTLB:      /* Data TLB error                           */
+    case POWERPC_EXCP_ITLB:      /* Instruction TLB error                    */
+        break;
+    case POWERPC_EXCP_DEBUG:     /* Debug interrupt                          */
+        if (env->flags & POWERPC_FLAG_DE) {
+            /* FIXME: choose one or the other based on CPU type */
+            srr0 = SPR_BOOKE_DSRR0;
+            srr1 = SPR_BOOKE_DSRR1;
+
+            env->spr[SPR_BOOKE_CSRR0] = env->nip;
+            env->spr[SPR_BOOKE_CSRR1] = msr;
+
+            /* DBSR already modified by caller */
+        } else {
+            cpu_abort(cs, "Debug exception triggered on unsupported model\n");
+        }
+        break;
+    case POWERPC_EXCP_SPEU:   /* SPE/embedded floating-point unavailable/VPU  */
+        env->spr[SPR_BOOKE_ESR] = ESR_SPV;
+        break;
+    case POWERPC_EXCP_DOORI:     /* Embedded doorbell interrupt              */
+        break;
+    case POWERPC_EXCP_DOORCI:    /* Embedded doorbell critical interrupt     */
+        srr0 = SPR_BOOKE_CSRR0;
+        srr1 = SPR_BOOKE_CSRR1;
+        break;
+    case POWERPC_EXCP_RESET:     /* System reset exception                   */
+        /* A power-saving exception sets ME, otherwise it is unchanged */
+        if (msr_pow) {
+            /* indicate that we resumed from power save mode */
+            msr |= 0x10000;
+            new_msr |= ((target_ulong)1 << MSR_ME);
+        }
+        if (env->msr_mask & MSR_HVB) {
+            /*
+             * ISA specifies HV, but can be delivered to guest with HV
+             * clear (e.g., see FWNMI in PAPR, NMI injection in QEMU).
+             */
+            new_msr |= (target_ulong)MSR_HVB;
+        } else {
+            if (msr_pow) {
+                cpu_abort(cs, "Trying to deliver power-saving system reset "
+                          "exception %d with no HV support\n", excp);
+            }
+        }
+        break;
+    case POWERPC_EXCP_DSEG:      /* Data segment exception                   */
+    case POWERPC_EXCP_ISEG:      /* Instruction segment exception            */
+    case POWERPC_EXCP_TRACE:     /* Trace exception                          */
+        break;
+    case POWERPC_EXCP_HISI:      /* Hypervisor instruction storage exception */
+        msr |= env->error_code;
+        /* fall through */
+    case POWERPC_EXCP_HDECR:     /* Hypervisor decrementer exception         */
+    case POWERPC_EXCP_HDSI:      /* Hypervisor data storage exception        */
+    case POWERPC_EXCP_HDSEG:     /* Hypervisor data segment exception        */
+    case POWERPC_EXCP_HISEG:     /* Hypervisor instruction segment exception */
+    case POWERPC_EXCP_SDOOR_HV:  /* Hypervisor Doorbell interrupt            */
+    case POWERPC_EXCP_HV_EMU:
+    case POWERPC_EXCP_HVIRT:     /* Hypervisor virtualization                */
+        srr0 = SPR_HSRR0;
+        srr1 = SPR_HSRR1;
+        new_msr |= (target_ulong)MSR_HVB;
+        new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
+        break;
+    case POWERPC_EXCP_VPU:       /* Vector unavailable exception             */
+    case POWERPC_EXCP_VSXU:       /* VSX unavailable exception               */
+    case POWERPC_EXCP_FU:         /* Facility unavailable exception          */
+#ifdef TARGET_PPC64
+        env->spr[SPR_FSCR] |= ((target_ulong)env->error_code << 56);
+#endif
+        break;
+    case POWERPC_EXCP_HV_FU:     /* Hypervisor Facility Unavailable Exception */
+#ifdef TARGET_PPC64
+        env->spr[SPR_HFSCR] |= ((target_ulong)env->error_code << FSCR_IC_POS);
+        srr0 = SPR_HSRR0;
+        srr1 = SPR_HSRR1;
+        new_msr |= (target_ulong)MSR_HVB;
+        new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
+#endif
+        break;
+    case POWERPC_EXCP_PIT:       /* Programmable interval timer interrupt    */
+        trace_ppc_excp_print("PIT");
+        break;
+    case POWERPC_EXCP_IFTLB:     /* Instruction fetch TLB error              */
+    case POWERPC_EXCP_DLTLB:     /* Data load TLB miss                       */
+    case POWERPC_EXCP_DSTLB:     /* Data store TLB miss                      */
+        switch (excp_model) {
+        case POWERPC_EXCP_602:
+        case POWERPC_EXCP_603:
+        case POWERPC_EXCP_G2:
+            /* Swap temporary saved registers with GPRs */
+            if (!(new_msr & ((target_ulong)1 << MSR_TGPR))) {
+                new_msr |= (target_ulong)1 << MSR_TGPR;
+                hreg_swap_gpr_tgpr(env);
+            }
+            /* fall through */
+        case POWERPC_EXCP_7x5:
+            ppc_excp_debug_sw_tlb(env, excp);
+
+            msr |= env->crf[0] << 28;
+            msr |= env->error_code; /* key, D/I, S/L bits */
+            /* Set way using a LRU mechanism */
+            msr |= ((env->last_way + 1) & (env->nb_ways - 1)) << 17;
+            break;
+        default:
+            cpu_abort(cs, "Invalid TLB miss exception\n");
+            break;
+        }
+        break;
+    case POWERPC_EXCP_EFPDI:     /* Embedded floating-point data interrupt   */
+    case POWERPC_EXCP_EFPRI:     /* Embedded floating-point round interrupt  */
+    case POWERPC_EXCP_EPERFM:    /* Embedded performance monitor interrupt   */
+    case POWERPC_EXCP_IO:        /* IO error exception                       */
+    case POWERPC_EXCP_RUNM:      /* Run mode exception                       */
+    case POWERPC_EXCP_EMUL:      /* Emulation trap exception                 */
+    case POWERPC_EXCP_FPA:       /* Floating-point assist exception          */
+    case POWERPC_EXCP_DABR:      /* Data address breakpoint                  */
+    case POWERPC_EXCP_IABR:      /* Instruction address breakpoint           */
+    case POWERPC_EXCP_SMI:       /* System management interrupt              */
+    case POWERPC_EXCP_THERM:     /* Thermal interrupt                        */
+    case POWERPC_EXCP_PERFM:     /* Embedded performance monitor interrupt   */
+    case POWERPC_EXCP_VPUA:      /* Vector assist exception                  */
+    case POWERPC_EXCP_SOFTP:     /* Soft patch exception                     */
+    case POWERPC_EXCP_MAINT:     /* Maintenance exception                    */
+    case POWERPC_EXCP_MEXTBR:    /* Maskable external breakpoint             */
+    case POWERPC_EXCP_NMEXTBR:   /* Non maskable external breakpoint         */
+        cpu_abort(cs, "%s exception not implemented\n",
+                  powerpc_excp_name(excp));
+        break;
+    default:
+    excp_invalid:
+        cpu_abort(cs, "Invalid PowerPC exception %d. Aborting\n", excp);
+        break;
+    }
+
+    /* Sanity check */
+    if (!(env->msr_mask & MSR_HVB)) {
+        if (new_msr & MSR_HVB) {
+            cpu_abort(cs, "Trying to deliver HV exception (MSR) %d with "
+                      "no HV support\n", excp);
+        }
+        if (srr0 == SPR_HSRR0) {
+            cpu_abort(cs, "Trying to deliver HV exception (HSRR) %d with "
+                      "no HV support\n", excp);
+        }
+    }
+
+    /*
+     * Sort out endianness of interrupt, this differs depending on the
+     * CPU, the HV mode, etc...
+     */
+    if (ppc_interrupts_little_endian(cpu, !!(new_msr & MSR_HVB))) {
+        new_msr |= (target_ulong)1 << MSR_LE;
+    }
+
+#if defined(TARGET_PPC64)
+    if (excp_model == POWERPC_EXCP_BOOKE) {
+        if (env->spr[SPR_BOOKE_EPCR] & EPCR_ICM) {
+            /* Cat.64-bit: EPCR.ICM is copied to MSR.CM */
+            new_msr |= (target_ulong)1 << MSR_CM;
+        } else {
+            vector = (uint32_t)vector;
+        }
+    } else {
+        if (!msr_isf && !mmu_is_64bit(env->mmu_model)) {
+            vector = (uint32_t)vector;
+        } else {
+            new_msr |= (target_ulong)1 << MSR_SF;
+        }
+    }
+#endif
+
+    if (excp != POWERPC_EXCP_SYSCALL_VECTORED) {
+        /* Save PC */
+        env->spr[srr0] = env->nip;
+
+        /* Save MSR */
+        env->spr[srr1] = msr;
+    }
+
+    /* This can update new_msr and vector if AIL applies */
+    ppc_excp_apply_ail(cpu, excp_model, excp, msr, &new_msr, &vector);
+
+    powerpc_set_excp_state(cpu, vector, new_msr);
+}
+
 /*
  * Note that this function should be greatly optimized when called
  * with a constant excp, from ppc_hw_interrupt
@@ -872,6 +1343,9 @@ static void powerpc_excp(PowerPCCPU *cpu, int excp)
     CPUPPCState *env = &cpu->env;
 
     switch (env->excp_model) {
+    case POWERPC_EXCP_40x:
+        powerpc_excp_40x(cpu, excp);
+        break;
     default:
         powerpc_excp_legacy(cpu, excp);
     }
-- 
2.33.1



  parent reply	other threads:[~2022-01-10 18:24 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-10 18:15 [PATCH 0/8] target/ppc: powerpc_excp improvements [40x] (3/n) Fabiano Rosas
2022-01-10 18:15 ` [PATCH 1/8] target/ppc: 405: Add missing MSR bits to msr_mask Fabiano Rosas
2022-01-11  2:04   ` David Gibson
2022-01-11  2:07     ` David Gibson
2022-01-17 21:12   ` Fabiano Rosas
2022-01-18  8:40     ` David Gibson
2022-01-10 18:15 ` [PATCH 2/8] target/ppc: 405: Add missing exception handlers Fabiano Rosas
2022-01-11  2:10   ` David Gibson
2022-01-14 21:46     ` Fabiano Rosas
2022-01-15  7:05       ` David Gibson
2022-01-10 18:15 ` Fabiano Rosas [this message]
2022-01-11  2:20   ` [PATCH 3/8] target/ppc: Introduce powerpc_excp_40x David Gibson
2022-01-10 18:15 ` [PATCH 4/8] squash " Fabiano Rosas
2022-01-10 18:51   ` BALATON Zoltan
2022-01-10 19:00     ` Fabiano Rosas
2022-01-10 18:15 ` [PATCH 5/8] target/ppc: 405: Critical exceptions cleanup Fabiano Rosas
2022-01-11  2:26   ` David Gibson
2022-01-10 18:15 ` [PATCH 6/8] target/ppc: 405: Machine check exception cleanup Fabiano Rosas
2022-01-11  2:26   ` David Gibson
2022-01-10 18:15 ` [PATCH 7/8] target/ppc: 405: External " Fabiano Rosas
2022-01-11  2:28   ` David Gibson
2022-01-10 18:15 ` [PATCH 8/8] target/ppc: 405: System call " Fabiano Rosas
2022-01-11  2:31   ` David Gibson
2022-01-11 12:48     ` Fabiano Rosas
2022-01-11  8:37 ` [PATCH 0/8] target/ppc: powerpc_excp improvements [40x] (3/n) Cédric Le Goater

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