Hexagon: add utimer impl for userspace

Signed-off-by: Brian Cain <bcain@quicinc.com>

target/hexagon/op_helper.c

@@ -17,6 +17,7 @@
 
 #include "qemu/osdep.h"
 #include "qemu/log.h"
+#include "qemu/timer.h"
 #include "exec/exec-all.h"
 #include "exec/cpu_ldst.h"
 #include "exec/helper-proto.h"
@@ -2656,6 +2657,12 @@ uint32_t HELPER(creg_read)(CPUHexagonState *env, uint32_t reg)
 {
     /* These are handled directly by gen_read_ctrl_reg(). */
     g_assert(reg != HEX_REG_UPCYCLELO && reg != HEX_REG_UPCYCLEHI);
+
+    if (reg == HEX_REG_UTIMERHI) {
+        return cpu_get_host_ticks() >> 32;
+    } else if (reg == HEX_REG_UTIMERLO) {
+        return extract32(cpu_get_host_ticks(), 0, 32);
+    }
     return 0;
 }
 
@@ -2665,6 +2672,9 @@ uint64_t HELPER(creg_read_pair)(CPUHexagonState *env, uint32_t reg)
         /* Pretend SSR[CE] is always set. */
         return hexagon_get_sys_pcycle_count(env);
     }
+    if (reg == HEX_REG_UTIMERLO) {
+        return cpu_get_host_ticks();
+    }
     return 0;
 }
 #endif

tests/tcg/hexagon/Makefile.target

@@ -54,6 +54,7 @@ HEX_TESTS += invalid-slots
 HEX_TESTS += unaligned_pc
 HEX_TESTS += unaligned_pc_multi_cof
 HEX_TESTS += multiple-writes
+HEX_TESTS += utimer
 
 run-unaligned_pc: unaligned_pc
 run-unaligned_pc_multi_cof: unaligned_pc_multi_cof
@@ -125,6 +126,7 @@ overflow: overflow.c hex_test.h
 preg_alias: preg_alias.c hex_test.h
 read_write_overlap: read_write_overlap.c hex_test.h
 reg_mut: reg_mut.c hex_test.h
+utimer: utimer.c hex_test.h
 
 # This test has to be compiled for the -mv67t target
 usr: usr.c hex_test.h

tests/tcg/hexagon/utimer.c

@@ -0,0 +1,50 @@
+/*
+ * Copyright(c) 2022-2023 Qualcomm Innovation Center, Inc. All Rights Reserved.
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdint.h>
+#include <stdio.h>
+
+static int err;
+
+#include "hex_test.h"
+
+static uint64_t get_time()
+{
+    uint64_t time;
+    asm volatile("%0 = utimer\n\t"
+                 : "=r"(time)
+                 :
+                 :
+                 );
+    return time;
+}
+
+static uint64_t get_time_from_regs()
+{
+    uint32_t time_low;
+    uint32_t time_high;
+    asm volatile("%0 = utimerhi\n\t"
+                 "%1 = utimerlo\n\t"
+                 : "=r"(time_high), "=r"(time_low)
+                 :
+                 :
+                 );
+    return ((uint64_t)time_high << 32) | (uint64_t)time_low;
+}
+
+
+int main()
+{
+    err = 0;
+
+    uint64_t t0 = get_time();
+    check64_ne(t0, 0);
+
+    uint64_t t1 = get_time_from_regs();
+    check64_ne(t1, 0);
+
+    puts(err ? "FAIL" : "PASS");
+    return err;
+}