[PATCH 17/39] target/hexagon: Implement software interrupt

[Brian Cain <brian.cain@oss.qualcomm.com>]

From: Brian Cain <bcain@quicinc.com>

Co-authored-by: Mike Lambert <mlambert@quicinc.com>
Signed-off-by: Brian Cain <brian.cain@oss.qualcomm.com>
---
 target/hexagon/cpu.h       |   1 -
 target/hexagon/hexswi.h    |  17 +++
 target/hexagon/cpu.c       |   2 +
 target/hexagon/hexswi.c    | 258 +++++++++++++++++++++++++++++++++++++
 target/hexagon/op_helper.c |   1 +
 5 files changed, 278 insertions(+), 1 deletion(-)
 create mode 100644 target/hexagon/hexswi.h
 create mode 100644 target/hexagon/hexswi.c

diff --git a/target/hexagon/cpu.h b/target/hexagon/cpu.h
index dabee310c5..045581d7be 100644
--- a/target/hexagon/cpu.h
+++ b/target/hexagon/cpu.h
@@ -256,5 +256,4 @@ typedef HexagonCPU ArchCPU;
 void hexagon_translate_init(void);
 void hexagon_translate_code(CPUState *cs, TranslationBlock *tb,
                             int *max_insns, vaddr pc, void *host_pc);
-
 #endif /* HEXAGON_CPU_H */
diff --git a/target/hexagon/hexswi.h b/target/hexagon/hexswi.h
new file mode 100644
index 0000000000..5d232cb06c
--- /dev/null
+++ b/target/hexagon/hexswi.h
@@ -0,0 +1,17 @@
+/*
+ * Copyright(c) 2025 Qualcomm Innovation Center, Inc. All Rights Reserved.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef HEXSWI_H
+#define HEXSWI_H
+
+
+#include "cpu.h"
+
+void hexagon_cpu_do_interrupt(CPUState *cpu);
+void register_trap_exception(CPUHexagonState *env, int type, int imm,
+                             target_ulong PC);
+
+#endif /* HEXSWI_H */
diff --git a/target/hexagon/cpu.c b/target/hexagon/cpu.c
index 89a051b41d..843be8221f 100644
--- a/target/hexagon/cpu.c
+++ b/target/hexagon/cpu.c
@@ -33,6 +33,8 @@
 #ifndef CONFIG_USER_ONLY
 #include "sys_macros.h"
 #include "qemu/main-loop.h"
+#include "hex_interrupts.h"
+#include "hexswi.h"
 #endif
 
 static void hexagon_v66_cpu_init(Object *obj) { }
diff --git a/target/hexagon/hexswi.c b/target/hexagon/hexswi.c
new file mode 100644
index 0000000000..5fcf9b2be9
--- /dev/null
+++ b/target/hexagon/hexswi.c
@@ -0,0 +1,258 @@
+/*
+ * Copyright(c) 2019-2025 Qualcomm Innovation Center, Inc. All Rights Reserved.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "cpu.h"
+#ifdef CONFIG_USER_ONLY
+#include "exec/helper-proto.h"
+#include "qemu.h"
+#endif
+#include "exec/cpu_ldst.h"
+#include "exec/exec-all.h"
+#include "qemu/log.h"
+#include "qemu/main-loop.h"
+#include "arch.h"
+#include "internal.h"
+#include "macros.h"
+#include "sys_macros.h"
+#include "tcg/tcg-op.h"
+#ifndef CONFIG_USER_ONLY
+#include "hex_mmu.h"
+#include "hexswi.h"
+#endif
+
+#ifndef CONFIG_USER_ONLY
+
+
+static void set_addresses(CPUHexagonState *env, target_ulong pc_offset,
+                          target_ulong exception_index)
+
+{
+    arch_set_system_reg(env, HEX_SREG_ELR,
+                        arch_get_thread_reg(env, HEX_REG_PC) + pc_offset);
+    arch_set_thread_reg(env, HEX_REG_PC,
+                        arch_get_system_reg(env, HEX_SREG_EVB) |
+                            (exception_index << 2));
+}
+
+static const char *event_name[] = {
+    [HEX_EVENT_RESET] = "HEX_EVENT_RESET",
+    [HEX_EVENT_IMPRECISE] = "HEX_EVENT_IMPRECISE",
+    [HEX_EVENT_TLB_MISS_X] = "HEX_EVENT_TLB_MISS_X",
+    [HEX_EVENT_TLB_MISS_RW] = "HEX_EVENT_TLB_MISS_RW",
+    [HEX_EVENT_TRAP0] = "HEX_EVENT_TRAP0",
+    [HEX_EVENT_TRAP1] = "HEX_EVENT_TRAP1",
+    [HEX_EVENT_FPTRAP] = "HEX_EVENT_FPTRAP",
+    [HEX_EVENT_DEBUG] = "HEX_EVENT_DEBUG",
+    [HEX_EVENT_INT0] = "HEX_EVENT_INT0",
+    [HEX_EVENT_INT1] = "HEX_EVENT_INT1",
+    [HEX_EVENT_INT2] = "HEX_EVENT_INT2",
+    [HEX_EVENT_INT3] = "HEX_EVENT_INT3",
+    [HEX_EVENT_INT4] = "HEX_EVENT_INT4",
+    [HEX_EVENT_INT5] = "HEX_EVENT_INT5",
+    [HEX_EVENT_INT6] = "HEX_EVENT_INT6",
+    [HEX_EVENT_INT7] = "HEX_EVENT_INT7",
+    [HEX_EVENT_INT8] = "HEX_EVENT_INT8",
+    [HEX_EVENT_INT9] = "HEX_EVENT_INT9",
+    [HEX_EVENT_INTA] = "HEX_EVENT_INTA",
+    [HEX_EVENT_INTB] = "HEX_EVENT_INTB",
+    [HEX_EVENT_INTC] = "HEX_EVENT_INTC",
+    [HEX_EVENT_INTD] = "HEX_EVENT_INTD",
+    [HEX_EVENT_INTE] = "HEX_EVENT_INTE",
+    [HEX_EVENT_INTF] = "HEX_EVENT_INTF"
+};
+
+void hexagon_cpu_do_interrupt(CPUState *cs)
+
+{
+    CPUHexagonState *env = cpu_env(cs);
+    BQL_LOCK_GUARD();
+
+    qemu_log_mask(CPU_LOG_INT, "\t%s: event 0x%x:%s, cause 0x%x(%d)\n",
+                  __func__, cs->exception_index,
+                  event_name[cs->exception_index], env->cause_code,
+                  env->cause_code);
+
+    env->llsc_addr = ~0;
+
+    uint32_t ssr = arch_get_system_reg(env, HEX_SREG_SSR);
+    if (GET_SSR_FIELD(SSR_EX, ssr) == 1) {
+        arch_set_system_reg(env, HEX_SREG_DIAG, env->cause_code);
+        env->cause_code = HEX_CAUSE_DOUBLE_EXCEPT;
+        cs->exception_index = HEX_EVENT_PRECISE;
+    }
+
+    switch (cs->exception_index) {
+    case HEX_EVENT_TRAP0:
+        if (env->cause_code == 0) {
+            qemu_log_mask(LOG_UNIMP,
+                          "trap0 is unhandled, no semihosting available\n");
+        }
+
+        hexagon_ssr_set_cause(env, env->cause_code);
+        set_addresses(env, 4, cs->exception_index);
+        break;
+
+    case HEX_EVENT_TRAP1:
+        hexagon_ssr_set_cause(env, env->cause_code);
+        set_addresses(env, 4, cs->exception_index);
+        break;
+
+    case HEX_EVENT_TLB_MISS_X:
+        switch (env->cause_code) {
+        case HEX_CAUSE_TLBMISSX_CAUSE_NORMAL:
+        case HEX_CAUSE_TLBMISSX_CAUSE_NEXTPAGE:
+            qemu_log_mask(CPU_LOG_MMU,
+                          "TLB miss EX exception (0x%x) caught: "
+                          "Cause code (0x%x) "
+                          "TID = 0x%" PRIx32 ", PC = 0x%" PRIx32
+                          ", BADVA = 0x%" PRIx32 "\n",
+                          cs->exception_index, env->cause_code, env->threadId,
+                          arch_get_thread_reg(env, HEX_REG_PC),
+                          arch_get_system_reg(env, HEX_SREG_BADVA));
+
+            hexagon_ssr_set_cause(env, env->cause_code);
+            set_addresses(env, 0, cs->exception_index);
+            break;
+
+        default:
+            cpu_abort(cs,
+                      "1:Hexagon exception %d/0x%x: "
+                      "Unknown cause code %d/0x%x\n",
+                      cs->exception_index, cs->exception_index, env->cause_code,
+                      env->cause_code);
+            break;
+        }
+        break;
+
+    case HEX_EVENT_TLB_MISS_RW:
+        switch (env->cause_code) {
+        case HEX_CAUSE_TLBMISSRW_CAUSE_READ:
+        case HEX_CAUSE_TLBMISSRW_CAUSE_WRITE:
+            qemu_log_mask(CPU_LOG_MMU,
+                          "TLB miss RW exception (0x%x) caught: "
+                          "Cause code (0x%x) "
+                          "TID = 0x%" PRIx32 ", PC = 0x%" PRIx32
+                          ", BADVA = 0x%" PRIx32 "\n",
+                          cs->exception_index, env->cause_code, env->threadId,
+                          env->gpr[HEX_REG_PC],
+                          arch_get_system_reg(env, HEX_SREG_BADVA));
+
+            hexagon_ssr_set_cause(env, env->cause_code);
+            set_addresses(env, 0, cs->exception_index);
+            /* env->sreg[HEX_SREG_BADVA] is set when the exception is raised */
+            break;
+
+        default:
+            cpu_abort(cs,
+                      "2:Hexagon exception %d/0x%x: "
+                      "Unknown cause code %d/0x%x\n",
+                      cs->exception_index, cs->exception_index, env->cause_code,
+                      env->cause_code);
+            break;
+        }
+        break;
+
+    case HEX_EVENT_FPTRAP:
+        hexagon_ssr_set_cause(env, env->cause_code);
+        arch_set_thread_reg(env, HEX_REG_PC,
+                            arch_get_system_reg(env, HEX_SREG_EVB) |
+                                (cs->exception_index << 2));
+        break;
+
+    case HEX_EVENT_DEBUG:
+        hexagon_ssr_set_cause(env, env->cause_code);
+        set_addresses(env, 0, cs->exception_index);
+        qemu_log_mask(LOG_UNIMP, "single-step exception is not handled\n");
+        break;
+
+    case HEX_EVENT_PRECISE:
+        switch (env->cause_code) {
+        case HEX_CAUSE_FETCH_NO_XPAGE:
+        case HEX_CAUSE_FETCH_NO_UPAGE:
+        case HEX_CAUSE_PRIV_NO_READ:
+        case HEX_CAUSE_PRIV_NO_UREAD:
+        case HEX_CAUSE_PRIV_NO_WRITE:
+        case HEX_CAUSE_PRIV_NO_UWRITE:
+        case HEX_CAUSE_MISALIGNED_LOAD:
+        case HEX_CAUSE_MISALIGNED_STORE:
+        case HEX_CAUSE_PC_NOT_ALIGNED:
+            qemu_log_mask(CPU_LOG_MMU,
+                          "MMU permission exception (0x%x) caught: "
+                          "Cause code (0x%x) "
+                          "TID = 0x%" PRIx32 ", PC = 0x%" PRIx32
+                          ", BADVA = 0x%" PRIx32 "\n",
+                          cs->exception_index, env->cause_code, env->threadId,
+                          env->gpr[HEX_REG_PC],
+                          arch_get_system_reg(env, HEX_SREG_BADVA));
+
+
+            hexagon_ssr_set_cause(env, env->cause_code);
+            set_addresses(env, 0, cs->exception_index);
+            /* env->sreg[HEX_SREG_BADVA] is set when the exception is raised */
+            break;
+
+        case HEX_CAUSE_DOUBLE_EXCEPT:
+        case HEX_CAUSE_PRIV_USER_NO_SINSN:
+        case HEX_CAUSE_PRIV_USER_NO_GINSN:
+        case HEX_CAUSE_INVALID_OPCODE:
+        case HEX_CAUSE_NO_COPROC_ENABLE:
+        case HEX_CAUSE_NO_COPROC2_ENABLE:
+        case HEX_CAUSE_UNSUPORTED_HVX_64B:
+        case HEX_CAUSE_REG_WRITE_CONFLICT:
+        case HEX_CAUSE_VWCTRL_WINDOW_MISS:
+            hexagon_ssr_set_cause(env, env->cause_code);
+            set_addresses(env, 0, cs->exception_index);
+            break;
+
+        case HEX_CAUSE_COPROC_LDST:
+            hexagon_ssr_set_cause(env, env->cause_code);
+            set_addresses(env, 0, cs->exception_index);
+            break;
+
+        case HEX_CAUSE_STACK_LIMIT:
+            hexagon_ssr_set_cause(env, env->cause_code);
+            set_addresses(env, 0, cs->exception_index);
+            break;
+
+        default:
+            cpu_abort(cs,
+                      "3:Hexagon exception %d/0x%x: "
+                      "Unknown cause code %d/0x%x\n",
+                      cs->exception_index, cs->exception_index, env->cause_code,
+                      env->cause_code);
+            break;
+        }
+        break;
+
+    case HEX_EVENT_IMPRECISE:
+        qemu_log_mask(LOG_UNIMP,
+                "Imprecise exception: this case is not yet handled");
+        break;
+
+    default:
+        qemu_log_mask(LOG_UNIMP,
+                "Hexagon Unsupported exception 0x%x/0x%x\n",
+                  cs->exception_index, env->cause_code);
+        break;
+    }
+
+    cs->exception_index = HEX_EVENT_NONE;
+}
+
+void register_trap_exception(CPUHexagonState *env, int traptype, int imm,
+                             target_ulong PC)
+{
+    CPUState *cs = env_cpu(env);
+
+    cs->exception_index = (traptype == 0) ? HEX_EVENT_TRAP0 : HEX_EVENT_TRAP1;
+    ASSERT_DIRECT_TO_GUEST_UNSET(env, cs->exception_index);
+
+    env->cause_code = imm;
+    env->gpr[HEX_REG_PC] = PC;
+    cpu_loop_exit(cs);
+}
+#endif
diff --git a/target/hexagon/op_helper.c b/target/hexagon/op_helper.c
index 42805d0f1d..687e7f45c2 100644
--- a/target/hexagon/op_helper.c
+++ b/target/hexagon/op_helper.c
@@ -38,6 +38,7 @@
 #include "hex_mmu.h"
 #include "hw/intc/l2vic.h"
 #include "hex_interrupts.h"
+#include "hexswi.h"
 #endif
 
 #define SF_BIAS        127
-- 
2.34.1