[PATCH v5 0/6] target/riscv: Initial support for the Sdtrig extension via M-mode CSRs

[PATCH v5 0/6] target/riscv: Initial support for the Sdtrig extension via M-mode CSRs

[Bin Meng]

This adds initial support for the Sdtrig extension via the Trigger Module,
as defined in the RISC-V Debug Specification [1].

Only "Address / Data Match" trigger (type 2) is implemented as of now,
which is mainly used for hardware breakpoint and watchpoint. The number
of type 2 triggers implemented is 2, which is the number that we can
find in the SiFive U54/U74 cores.

[1] https://github.com/riscv/riscv-debug-spec/raw/master/riscv-debug-stable.pdf

Changes in v5:
- rebase against riscv-to-apply.next
- drop patch 1 in v4 which is already in riscv-to-apply.next
- adjust patch order to let patch 2 in v4 come later

Changes in v4:
- move riscv_trigger_init() call to riscv_cpu_reset()

Changes in v3:
- add riscv_trigger_init(), moved from patch #1 to this patch
- enable debug feature by default for all CPUs

Changes in v2:
- use 0 instead of GETPC()
- change the config option to 'disabled' by default
- new patch: add debug state description

Bin Meng (6):
  target/riscv: debug: Implement debug related TCGCPUOps
  target/riscv: cpu: Add a config option for native debug
  target/riscv: csr: Hook debug CSR read/write
  target/riscv: machine: Add debug state description
  target/riscv: cpu: Enable native debug feature
  hw/core: tcg-cpu-ops.h: Update comments of debug_check_watchpoint()

 include/hw/core/tcg-cpu-ops.h |   1 +
 target/riscv/cpu.h            |   4 +-
 target/riscv/debug.h          |   6 ++
 target/riscv/cpu.c            |  12 ++++
 target/riscv/csr.c            |  57 +++++++++++++++++++
 target/riscv/debug.c          | 102 ++++++++++++++++++++++++++++++++++
 target/riscv/machine.c        |  32 +++++++++++
 7 files changed, 213 insertions(+), 1 deletion(-)

-- 
2.25.1

[PATCH v5 1/6] target/riscv: debug: Implement debug related TCGCPUOps

[Bin Meng]

From: Bin Meng <bin.meng@windriver.com>

Implement .debug_excp_handler, .debug_check_{breakpoint, watchpoint}
TCGCPUOps and hook them into riscv_tcg_ops.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
---

(no changes since v2)

Changes in v2:
- use 0 instead of GETPC()

 target/riscv/debug.h |  4 +++
 target/riscv/cpu.c   |  3 ++
 target/riscv/debug.c | 75 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 82 insertions(+)

diff --git a/target/riscv/debug.h b/target/riscv/debug.h
index fbc5f946e2..fb21706e1c 100644
--- a/target/riscv/debug.h
+++ b/target/riscv/debug.h
@@ -105,4 +105,8 @@ void tselect_csr_write(CPURISCVState *env, target_ulong val);
 target_ulong tdata_csr_read(CPURISCVState *env, int tdata_index);
 void tdata_csr_write(CPURISCVState *env, int tdata_index, target_ulong val);
 
+void riscv_cpu_debug_excp_handler(CPUState *cs);
+bool riscv_cpu_debug_check_breakpoint(CPUState *cs);
+bool riscv_cpu_debug_check_watchpoint(CPUState *cs, CPUWatchpoint *wp);
+
 #endif /* RISCV_DEBUG_H */
diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 94f9434411..8919928f4f 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -880,6 +880,9 @@ static const struct TCGCPUOps riscv_tcg_ops = {
     .do_interrupt = riscv_cpu_do_interrupt,
     .do_transaction_failed = riscv_cpu_do_transaction_failed,
     .do_unaligned_access = riscv_cpu_do_unaligned_access,
+    .debug_excp_handler = riscv_cpu_debug_excp_handler,
+    .debug_check_breakpoint = riscv_cpu_debug_check_breakpoint,
+    .debug_check_watchpoint = riscv_cpu_debug_check_watchpoint,
 #endif /* !CONFIG_USER_ONLY */
 };
 
diff --git a/target/riscv/debug.c b/target/riscv/debug.c
index c8cec39217..1a9392645e 100644
--- a/target/riscv/debug.c
+++ b/target/riscv/debug.c
@@ -337,3 +337,78 @@ void tdata_csr_write(CPURISCVState *env, int tdata_index, target_ulong val)
 
     return write_func(env, env->trigger_cur, tdata_index, val);
 }
+
+void riscv_cpu_debug_excp_handler(CPUState *cs)
+{
+    RISCVCPU *cpu = RISCV_CPU(cs);
+    CPURISCVState *env = &cpu->env;
+
+    if (cs->watchpoint_hit) {
+        if (cs->watchpoint_hit->flags & BP_CPU) {
+            cs->watchpoint_hit = NULL;
+            riscv_raise_exception(env, RISCV_EXCP_BREAKPOINT, 0);
+        }
+    } else {
+        if (cpu_breakpoint_test(cs, env->pc, BP_CPU)) {
+            riscv_raise_exception(env, RISCV_EXCP_BREAKPOINT, 0);
+        }
+    }
+}
+
+bool riscv_cpu_debug_check_breakpoint(CPUState *cs)
+{
+    RISCVCPU *cpu = RISCV_CPU(cs);
+    CPURISCVState *env = &cpu->env;
+    CPUBreakpoint *bp;
+    target_ulong ctrl;
+    target_ulong pc;
+    int i;
+
+    QTAILQ_FOREACH(bp, &cs->breakpoints, entry) {
+        for (i = 0; i < TRIGGER_TYPE2_NUM; i++) {
+            ctrl = env->type2_trig[i].mcontrol;
+            pc = env->type2_trig[i].maddress;
+
+            if ((ctrl & TYPE2_EXEC) && (bp->pc == pc)) {
+                /* check U/S/M bit against current privilege level */
+                if ((ctrl >> 3) & BIT(env->priv)) {
+                    return true;
+                }
+            }
+        }
+    }
+
+    return false;
+}
+
+bool riscv_cpu_debug_check_watchpoint(CPUState *cs, CPUWatchpoint *wp)
+{
+    RISCVCPU *cpu = RISCV_CPU(cs);
+    CPURISCVState *env = &cpu->env;
+    target_ulong ctrl;
+    target_ulong addr;
+    int flags;
+    int i;
+
+    for (i = 0; i < TRIGGER_TYPE2_NUM; i++) {
+        ctrl = env->type2_trig[i].mcontrol;
+        addr = env->type2_trig[i].maddress;
+        flags = 0;
+
+        if (ctrl & TYPE2_LOAD) {
+            flags |= BP_MEM_READ;
+        }
+        if (ctrl & TYPE2_STORE) {
+            flags |= BP_MEM_WRITE;
+        }
+
+        if ((wp->flags & flags) && (wp->vaddr == addr)) {
+            /* check U/S/M bit against current privilege level */
+            if ((ctrl >> 3) & BIT(env->priv)) {
+                return true;
+            }
+        }
+    }
+
+    return false;
+}
-- 
2.25.1

[PATCH v5 2/6] target/riscv: cpu: Add a config option for native debug

[Bin Meng]

From: Bin Meng <bin.meng@windriver.com>

Add a config option to enable support for native M-mode debug.
This is disabled by default and can be enabled with 'debug=true'.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
---

(no changes since v2)

Changes in v2:
- change the config option to 'disabled' by default

 target/riscv/cpu.h | 4 +++-
 target/riscv/cpu.c | 5 +++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index 39a9ff17d3..62e53e3653 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -79,7 +79,8 @@ enum {
     RISCV_FEATURE_PMP,
     RISCV_FEATURE_EPMP,
     RISCV_FEATURE_MISA,
-    RISCV_FEATURE_AIA
+    RISCV_FEATURE_AIA,
+    RISCV_FEATURE_DEBUG
 };
 
 /* Privileged specification version */
@@ -405,6 +406,7 @@ struct RISCVCPUConfig {
     bool pmp;
     bool epmp;
     bool aia;
+    bool debug;
     uint64_t resetvec;
 };
 
diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 8919928f4f..477961b619 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -548,6 +548,10 @@ static void riscv_cpu_realize(DeviceState *dev, Error **errp)
         riscv_set_feature(env, RISCV_FEATURE_AIA);
     }
 
+    if (cpu->cfg.debug) {
+        riscv_set_feature(env, RISCV_FEATURE_DEBUG);
+    }
+
     set_resetvec(env, cpu->cfg.resetvec);
 
     /* Validate that MISA_MXL is set properly. */
@@ -795,6 +799,7 @@ static Property riscv_cpu_properties[] = {
     DEFINE_PROP_BOOL("Zve64f", RISCVCPU, cfg.ext_zve64f, false),
     DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true),
     DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true),
+    DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, false),
 
     DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec),
     DEFINE_PROP_STRING("vext_spec", RISCVCPU, cfg.vext_spec),
-- 
2.25.1

[PATCH v5 3/6] target/riscv: csr: Hook debug CSR read/write

[Bin Meng]

From: Bin Meng <bin.meng@windriver.com>

This adds debug CSR read/write support to the RISC-V CSR RW table.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
---

(no changes since v4)

Changes in v4:
- move riscv_trigger_init() call to riscv_cpu_reset()

Changes in v3:
- add riscv_trigger_init(), moved from patch #1 to this patch

 target/riscv/debug.h |  2 ++
 target/riscv/cpu.c   |  4 ++++
 target/riscv/csr.c   | 57 ++++++++++++++++++++++++++++++++++++++++++++
 target/riscv/debug.c | 27 +++++++++++++++++++++
 4 files changed, 90 insertions(+)

diff --git a/target/riscv/debug.h b/target/riscv/debug.h
index fb21706e1c..27b9cac6b4 100644
--- a/target/riscv/debug.h
+++ b/target/riscv/debug.h
@@ -109,4 +109,6 @@ void riscv_cpu_debug_excp_handler(CPUState *cs);
 bool riscv_cpu_debug_check_breakpoint(CPUState *cs);
 bool riscv_cpu_debug_check_watchpoint(CPUState *cs, CPUWatchpoint *wp);
 
+void riscv_trigger_init(CPURISCVState *env);
+
 #endif /* RISCV_DEBUG_H */
diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 477961b619..85656cdcc3 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -466,6 +466,10 @@ static void riscv_cpu_reset(DeviceState *dev)
     set_default_nan_mode(1, &env->fp_status);
 
 #ifndef CONFIG_USER_ONLY
+    if (riscv_feature(env, RISCV_FEATURE_DEBUG)) {
+        riscv_trigger_init(env);
+    }
+
     if (kvm_enabled()) {
         kvm_riscv_reset_vcpu(cpu);
     }
diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index a09126a011..6ba85e7b5d 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -290,6 +290,15 @@ static RISCVException epmp(CPURISCVState *env, int csrno)
 
     return RISCV_EXCP_ILLEGAL_INST;
 }
+
+static RISCVException debug(CPURISCVState *env, int csrno)
+{
+    if (riscv_feature(env, RISCV_FEATURE_DEBUG)) {
+        return RISCV_EXCP_NONE;
+    }
+
+    return RISCV_EXCP_ILLEGAL_INST;
+}
 #endif
 
 /* User Floating-Point CSRs */
@@ -2677,6 +2686,48 @@ static RISCVException write_pmpaddr(CPURISCVState *env, int csrno,
     return RISCV_EXCP_NONE;
 }
 
+static RISCVException read_tselect(CPURISCVState *env, int csrno,
+                                   target_ulong *val)
+{
+    *val = tselect_csr_read(env);
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException write_tselect(CPURISCVState *env, int csrno,
+                                    target_ulong val)
+{
+    tselect_csr_write(env, val);
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException read_tdata(CPURISCVState *env, int csrno,
+                                 target_ulong *val)
+{
+    /* return 0 in tdata1 to end the trigger enumeration */
+    if (env->trigger_cur >= TRIGGER_NUM && csrno == CSR_TDATA1) {
+        *val = 0;
+        return RISCV_EXCP_NONE;
+    }
+
+    if (!tdata_available(env, csrno - CSR_TDATA1)) {
+        return RISCV_EXCP_ILLEGAL_INST;
+    }
+
+    *val = tdata_csr_read(env, csrno - CSR_TDATA1);
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException write_tdata(CPURISCVState *env, int csrno,
+                                  target_ulong val)
+{
+    if (!tdata_available(env, csrno - CSR_TDATA1)) {
+        return RISCV_EXCP_ILLEGAL_INST;
+    }
+
+    tdata_csr_write(env, csrno - CSR_TDATA1, val);
+    return RISCV_EXCP_NONE;
+}
+
 /*
  * Functions to access Pointer Masking feature registers
  * We have to check if current priv lvl could modify
@@ -3418,6 +3469,12 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
     [CSR_PMPADDR14] =  { "pmpaddr14", pmp, read_pmpaddr, write_pmpaddr },
     [CSR_PMPADDR15] =  { "pmpaddr15", pmp, read_pmpaddr, write_pmpaddr },
 
+    /* Debug CSRs */
+    [CSR_TSELECT]   =  { "tselect", debug, read_tselect, write_tselect },
+    [CSR_TDATA1]    =  { "tdata1",  debug, read_tdata,   write_tdata   },
+    [CSR_TDATA2]    =  { "tdata2",  debug, read_tdata,   write_tdata   },
+    [CSR_TDATA3]    =  { "tdata3",  debug, read_tdata,   write_tdata   },
+
     /* User Pointer Masking */
     [CSR_UMTE]    =    { "umte",    pointer_masking, read_umte,    write_umte    },
     [CSR_UPMMASK] =    { "upmmask", pointer_masking, read_upmmask, write_upmmask },
diff --git a/target/riscv/debug.c b/target/riscv/debug.c
index 1a9392645e..2f2a51c732 100644
--- a/target/riscv/debug.c
+++ b/target/riscv/debug.c
@@ -412,3 +412,30 @@ bool riscv_cpu_debug_check_watchpoint(CPUState *cs, CPUWatchpoint *wp)
 
     return false;
 }
+
+void riscv_trigger_init(CPURISCVState *env)
+{
+    target_ulong type2 = trigger_type(env, TRIGGER_TYPE_AD_MATCH);
+    int i;
+
+    /* type 2 triggers */
+    for (i = 0; i < TRIGGER_TYPE2_NUM; i++) {
+        /*
+         * type = TRIGGER_TYPE_AD_MATCH
+         * dmode = 0 (both debug and M-mode can write tdata)
+         * maskmax = 0 (unimplemented, always 0)
+         * sizehi = 0 (match against any size, RV64 only)
+         * hit = 0 (unimplemented, always 0)
+         * select = 0 (always 0, perform match on address)
+         * timing = 0 (always 0, trigger before instruction)
+         * sizelo = 0 (match against any size)
+         * action = 0 (always 0, raise a breakpoint exception)
+         * chain = 0 (unimplemented, always 0)
+         * match = 0 (always 0, when any compare value equals tdata2)
+         */
+        env->type2_trig[i].mcontrol = type2;
+        env->type2_trig[i].maddress = 0;
+        env->type2_trig[i].bp = NULL;
+        env->type2_trig[i].wp = NULL;
+    }
+}
-- 
2.25.1

[PATCH v5 4/6] target/riscv: machine: Add debug state description

[Bin Meng]

From: Bin Meng <bin.meng@windriver.com>

Add a subsection to machine.c to migrate debug CSR state.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
---

(no changes since v2)

Changes in v2:
- new patch: add debug state description

 target/riscv/machine.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/target/riscv/machine.c b/target/riscv/machine.c
index 243f567949..2a437b29a1 100644
--- a/target/riscv/machine.c
+++ b/target/riscv/machine.c
@@ -216,7 +216,38 @@ static const VMStateDescription vmstate_kvmtimer = {
         VMSTATE_UINT64(env.kvm_timer_time, RISCVCPU),
         VMSTATE_UINT64(env.kvm_timer_compare, RISCVCPU),
         VMSTATE_UINT64(env.kvm_timer_state, RISCVCPU),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static bool debug_needed(void *opaque)
+{
+    RISCVCPU *cpu = opaque;
+    CPURISCVState *env = &cpu->env;
+
+    return riscv_feature(env, RISCV_FEATURE_DEBUG);
+}
 
+static const VMStateDescription vmstate_debug_type2 = {
+    .name = "cpu/debug/type2",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINTTL(mcontrol, type2_trigger_t),
+        VMSTATE_UINTTL(maddress, type2_trigger_t),
+        VMSTATE_END_OF_LIST()
+   }
+};
+
+static const VMStateDescription vmstate_debug = {
+    .name = "cpu/debug",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = debug_needed,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINTTL(env.trigger_cur, RISCVCPU),
+        VMSTATE_STRUCT_ARRAY(env.type2_trig, RISCVCPU, TRIGGER_TYPE2_NUM,
+                             0, vmstate_debug_type2, type2_trigger_t),
         VMSTATE_END_OF_LIST()
     }
 };
@@ -315,6 +346,7 @@ const VMStateDescription vmstate_riscv_cpu = {
         &vmstate_rv128,
         &vmstate_kvmtimer,
         &vmstate_envcfg,
+        &vmstate_debug,
         NULL
     }
 };
-- 
2.25.1

[PATCH v5 5/6] target/riscv: cpu: Enable native debug feature

[Bin Meng]

From: Bin Meng <bin.meng@windriver.com>

Turn on native debug feature by default for all CPUs.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
---

(no changes since v3)

Changes in v3:
- enable debug feature by default for all CPUs

 target/riscv/cpu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 85656cdcc3..0c774056c5 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -803,7 +803,7 @@ static Property riscv_cpu_properties[] = {
     DEFINE_PROP_BOOL("Zve64f", RISCVCPU, cfg.ext_zve64f, false),
     DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true),
     DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true),
-    DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, false),
+    DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true),
 
     DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec),
     DEFINE_PROP_STRING("vext_spec", RISCVCPU, cfg.vext_spec),
-- 
2.25.1

[PATCH v5 6/6] hw/core: tcg-cpu-ops.h: Update comments of debug_check_watchpoint()

[Bin Meng]

From: Bin Meng <bin.meng@windriver.com>

This is now used by RISC-V as well. Update the comments.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
---

(no changes since v1)

 include/hw/core/tcg-cpu-ops.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/hw/core/tcg-cpu-ops.h b/include/hw/core/tcg-cpu-ops.h
index e13898553a..f98671ff32 100644
--- a/include/hw/core/tcg-cpu-ops.h
+++ b/include/hw/core/tcg-cpu-ops.h
@@ -90,6 +90,7 @@ struct TCGCPUOps {
     /**
      * @debug_check_watchpoint: return true if the architectural
      * watchpoint whose address has matched should really fire, used by ARM
+     * and RISC-V
      */
     bool (*debug_check_watchpoint)(CPUState *cpu, CPUWatchpoint *wp);
 
-- 
2.25.1

Re: [PATCH v5 0/6] target/riscv: Initial support for the Sdtrig extension via M-mode CSRs

[Alistair Francis]

On Thu, Apr 21, 2022 at 10:35 AM Bin Meng <bmeng.cn@gmail.com> wrote:
>
>
> This adds initial support for the Sdtrig extension via the Trigger Module,
> as defined in the RISC-V Debug Specification [1].
>
> Only "Address / Data Match" trigger (type 2) is implemented as of now,
> which is mainly used for hardware breakpoint and watchpoint. The number
> of type 2 triggers implemented is 2, which is the number that we can
> find in the SiFive U54/U74 cores.
>
> [1] https://github.com/riscv/riscv-debug-spec/raw/master/riscv-debug-stable.pdf
>
> Changes in v5:
> - rebase against riscv-to-apply.next
> - drop patch 1 in v4 which is already in riscv-to-apply.next
> - adjust patch order to let patch 2 in v4 come later
>
> Changes in v4:
> - move riscv_trigger_init() call to riscv_cpu_reset()
>
> Changes in v3:
> - add riscv_trigger_init(), moved from patch #1 to this patch
> - enable debug feature by default for all CPUs
>
> Changes in v2:
> - use 0 instead of GETPC()
> - change the config option to 'disabled' by default
> - new patch: add debug state description
>
> Bin Meng (6):
>   target/riscv: debug: Implement debug related TCGCPUOps
>   target/riscv: cpu: Add a config option for native debug
>   target/riscv: csr: Hook debug CSR read/write
>   target/riscv: machine: Add debug state description
>   target/riscv: cpu: Enable native debug feature
>   hw/core: tcg-cpu-ops.h: Update comments of debug_check_watchpoint()

Thanks!

Applied to riscv-to-apply.next

Alistair

>
>  include/hw/core/tcg-cpu-ops.h |   1 +
>  target/riscv/cpu.h            |   4 +-
>  target/riscv/debug.h          |   6 ++
>  target/riscv/cpu.c            |  12 ++++
>  target/riscv/csr.c            |  57 +++++++++++++++++++
>  target/riscv/debug.c          | 102 ++++++++++++++++++++++++++++++++++
>  target/riscv/machine.c        |  32 +++++++++++
>  7 files changed, 213 insertions(+), 1 deletion(-)
>
> --
> 2.25.1
>
>

Re: [PATCH v5 0/6] target/riscv: Initial support for the Sdtrig extension via M-mode CSRs

[Alistair Francis]

On Thu, Apr 21, 2022 at 10:35 AM Bin Meng <bmeng.cn@gmail.com> wrote:
>
>
> This adds initial support for the Sdtrig extension via the Trigger Module,
> as defined in the RISC-V Debug Specification [1].
>
> Only "Address / Data Match" trigger (type 2) is implemented as of now,
> which is mainly used for hardware breakpoint and watchpoint. The number
> of type 2 triggers implemented is 2, which is the number that we can
> find in the SiFive U54/U74 cores.
>
> [1] https://github.com/riscv/riscv-debug-spec/raw/master/riscv-debug-stable.pdf
>
> Changes in v5:
> - rebase against riscv-to-apply.next
> - drop patch 1 in v4 which is already in riscv-to-apply.next
> - adjust patch order to let patch 2 in v4 come later
>
> Changes in v4:
> - move riscv_trigger_init() call to riscv_cpu_reset()
>
> Changes in v3:
> - add riscv_trigger_init(), moved from patch #1 to this patch
> - enable debug feature by default for all CPUs
>
> Changes in v2:
> - use 0 instead of GETPC()
> - change the config option to 'disabled' by default
> - new patch: add debug state description
>
> Bin Meng (6):
>   target/riscv: debug: Implement debug related TCGCPUOps
>   target/riscv: cpu: Add a config option for native debug
>   target/riscv: csr: Hook debug CSR read/write
>   target/riscv: machine: Add debug state description
>   target/riscv: cpu: Enable native debug feature
>   hw/core: tcg-cpu-ops.h: Update comments of debug_check_watchpoint()

Thanks!

Applied to riscv-to-apply.next

Alistair

>
>  include/hw/core/tcg-cpu-ops.h |   1 +
>  target/riscv/cpu.h            |   4 +-
>  target/riscv/debug.h          |   6 ++
>  target/riscv/cpu.c            |  12 ++++
>  target/riscv/csr.c            |  57 +++++++++++++++++++
>  target/riscv/debug.c          | 102 ++++++++++++++++++++++++++++++++++
>  target/riscv/machine.c        |  32 +++++++++++
>  7 files changed, 213 insertions(+), 1 deletion(-)
>
> --
> 2.25.1
>
>