[PATCH v2 38/39] target/hexagon: Add guest reg reading functionality

[Brian Cain]

From: Matheus Tavares Bernardino <quic_mathb...@quicinc.com>

Signed-off-by: Matheus Tavares Bernardino <quic_mathb...@quicinc.com>
---
 target/hexagon/cpu.c       | 19 ++++++++++++++++++-
 target/hexagon/op_helper.c | 19 +++++++++++++++++--
 2 files changed, 35 insertions(+), 3 deletions(-)

diff --git a/target/hexagon/cpu.c b/target/hexagon/cpu.c
index 122761e657..751ba613cc 100644
--- a/target/hexagon/cpu.c
+++ b/target/hexagon/cpu.c
@@ -778,7 +778,24 @@ static void hexagon_cpu_class_init(ObjectClass *c, const 
void *data)
 #ifndef CONFIG_USER_ONLY
 uint32_t hexagon_greg_read(CPUHexagonState *env, uint32_t reg)
 {
-    g_assert_not_reached();
+    target_ulong ssr = arch_get_system_reg(env, HEX_SREG_SSR);
+    int ssr_ce = GET_SSR_FIELD(SSR_CE, ssr);
+
+    if (reg <= HEX_GREG_G3) {
+        return env->greg[reg];
+    }
+    switch (reg) {
+    case HEX_GREG_GPCYCLELO:
+        return ssr_ce ? hexagon_get_sys_pcycle_count_low(env) : 0;
+
+    case HEX_GREG_GPCYCLEHI:
+        return ssr_ce ? hexagon_get_sys_pcycle_count_high(env) : 0;
+
+    default:
+        qemu_log_mask(LOG_UNIMP, "reading greg %" PRId32
+                " not yet supported.\n", reg);
+        return 0;
+    }
 }
 #endif
 
diff --git a/target/hexagon/op_helper.c b/target/hexagon/op_helper.c
index 6783e1e7d1..1bc32769c6 100644
--- a/target/hexagon/op_helper.c
+++ b/target/hexagon/op_helper.c
@@ -1927,13 +1927,28 @@ uint64_t HELPER(sreg_read_pair)(CPUHexagonState *env, 
uint32_t reg)
 }
 
 uint32_t HELPER(greg_read)(CPUHexagonState *env, uint32_t reg)
+
 {
-    g_assert_not_reached();
+    return hexagon_greg_read(env, reg);
 }
 
 uint64_t HELPER(greg_read_pair)(CPUHexagonState *env, uint32_t reg)
+
 {
-    g_assert_not_reached();
+    if (reg == HEX_GREG_G0 || reg == HEX_GREG_G2) {
+        return (uint64_t)(env->greg[reg]) |
+               (((uint64_t)(env->greg[reg + 1])) << 32);
+    }
+    switch (reg) {
+    case HEX_GREG_GPCYCLELO: {
+        target_ulong ssr = arch_get_system_reg(env, HEX_SREG_SSR);
+        int ssr_ce = GET_SSR_FIELD(SSR_CE, ssr);
+        return ssr_ce ? hexagon_get_sys_pcycle_count(env) : 0;
+    }
+    default:
+        return (uint64_t)hexagon_greg_read(env, reg) |
+               ((uint64_t)(hexagon_greg_read(env, reg + 1)) << 32);
+    }
 }
 
 void HELPER(setprio)(CPUHexagonState *env, uint32_t thread, uint32_t prio)
-- 
2.34.1