diff --git a/common/inc/plat/config.h b/common/inc/plat/config.h
index 95756917..9664fad6 100644
--- a/common/inc/plat/config.h
+++ b/common/inc/plat/config.h
@@ -1,6 +1,6 @@
 #pragma once
 
-#if defined(PLATFORM_qemu_virt)
+#if defined(PLATFORM_qemu_virt) || defined(PLATFORM_qemu_virt4)
 #include "plat/qemu_virt.h"
 #elif defined(PLATFORM_sifive_unleashed)
 #include "plat/sifive_unleashed.h"
diff --git a/common/plat/qemu_virt.mk b/common/plat/qemu_virt.mk
index 8325ff1f..13d7d947 100644
--- a/common/plat/qemu_virt.mk
+++ b/common/plat/qemu_virt.mk
@@ -2,7 +2,8 @@ export ARCH=rv64imac_zicsr
 export ABI=lp64
 export CMODEL=medany
 export QEMU_MACHINE=virt
-export QEMU_SMP=4
+export QEMU_SMP=1
+export QEMU_OPTIONS=-icount 3
 export COMMON_INC:=${ROOT}/common/inc
 export COMMON_LIB:=${ROOT}/common/build/${PLATFORM}
 export STARTFILES:=${ROOT}/common/build/${PLATFORM}/start
diff --git a/common/plat/qemu_virt4.mk b/common/plat/qemu_virt4.mk
new file mode 100644
index 00000000..8325ff1f
--- /dev/null
+++ b/common/plat/qemu_virt4.mk
@@ -0,0 +1,9 @@
+export ARCH=rv64imac_zicsr
+export ABI=lp64
+export CMODEL=medany
+export QEMU_MACHINE=virt
+export QEMU_SMP=4
+export COMMON_INC:=${ROOT}/common/inc
+export COMMON_LIB:=${ROOT}/common/build/${PLATFORM}
+export STARTFILES:=${ROOT}/common/build/${PLATFORM}/start
+PLAT_SRCS=src/drivers/uart/ns16550a.c src/drivers/time.c
diff --git a/projects/ping-pong/app0/main.c b/projects/ping-pong/app0/main.c
index 36b69e48..dbeb4821 100644
--- a/projects/ping-pong/app0/main.c
+++ b/projects/ping-pong/app0/main.c
@@ -89,7 +89,7 @@ int main(void)
 	s3k_msg_t msg;
 	s3k_reply_t reply;
 	memcpy(msg.data, "pong", 5);
-	s3k_reg_write(S3K_REG_SERVTIME, 4500);
+	s3k_reg_write(S3K_REG_SERVTIME, 100);
 	while (1) {
 		do {
 			reply = s3k_sock_sendrecv(11, &msg);
diff --git a/projects/ping-pong/scripts/gdb.sh b/projects/ping-pong/scripts/gdb.sh
deleted file mode 100755
index 11faf60b..00000000
--- a/projects/ping-pong/scripts/gdb.sh
+++ /dev/null
@@ -1,31 +0,0 @@
-#!/bin/bash
-
-KERNEL=build/s3k
-APP0=build/app0
-APP1=build/app1
-
-if [[ -z "$TMUX" ]]; then
-	echo "No tmux session"
-	exit 0
-fi
-
-tmux split-window -d "./scripts/qemu.sh -s -S"
-sleep 0.5
-
-riscv64-unknown-elf-gdb				\
-	-ex "set confirm off"			\
-	-ex "set pagination off"		\
-	-ex "set output-radix 16"		\
-	-ex "symbol-file $KERNEL.elf"		\
-	-ex "add-symbol-file $APP0.elf"		\
-	-ex "add-symbol-file $APP1.elf"		\
-	-ex "j 0x80000000"			\
-	-ex "b _hang"				\
-	-ex "b *0x80010000"			\
-	-ex "b *0x80020000"			\
-	-ex "b handle_exception"		\
-	-ex "target remote localhost:1234"	\
-	-ex "layout split"			\
-	-ex "fs cmd"
-
-kill -SIGTERM $(pgrep qemu-system-*)
diff --git a/projects/ping-pong/scripts/qemu.sh b/projects/ping-pong/scripts/qemu.sh
deleted file mode 100755
index 38c08122..00000000
--- a/projects/ping-pong/scripts/qemu.sh
+++ /dev/null
@@ -1,11 +0,0 @@
-#!/bin/bash
-
-KERNEL=build/s3k
-APP0=build/app0
-APP1=build/app1
-
-qemu-system-riscv64 -M virt -smp 4 -m 128M		\
-	-nographic -bios none -kernel $KERNEL.elf	\
-	-device loader,file=$APP0.bin,addr=0x80010000	\
-	-device loader,file=$APP1.bin,addr=0x80020000	\
-	$@
diff --git a/scripts/qemu.sh b/scripts/qemu.sh
index dcb7961b..9a23b3a6 100755
--- a/scripts/qemu.sh
+++ b/scripts/qemu.sh
@@ -15,4 +15,4 @@ if [[ -z "$QEMU_SMP" ]]; then
 fi
 
 qemu-system-riscv64 -M $QEMU_MACHINE -smp $QEMU_SMP -m 128M -nographic -bios none \
-	$LOADER $@
+	$LOADER $QEMU_OPTIONS $@