[tools] Add qemu.sh options

Changes to qemu.sh:

- Now takes the -l/--log option to create the qemu log in jsix.log,
  otherwise does not ask qemu to log. (Way faster operations.)
- Remove the debug-isa-exit device when starting with the --debug flag,
  so that we can inspect panics
- Changed from 512M to 4G of ram

qemu.sh

@@ -3,9 +3,11 @@
 build="$(dirname $0)/build"
 assets="$(dirname $0)/assets"
 debug=""
+isaexit='-device isa-debug-exit,iobase=0xf4,iosize=0x04'
 debugtarget="${build}/jsix.elf"
 gfx="-nographic"
 vga="-vga none"
+log=""
 kvm=""
 cpu="Broadwell,+pdpe1gb"
 smp=4
@@ -19,6 +21,7 @@ while true; do
 			;;
 		-d | --debug)
 			debug="-s -S"
+            isaexit=""
             shift
 			;;
 		-g | --gfx)
@@ -38,6 +41,10 @@ while true; do
         -c | --cpus)
             smp=$2
             shift 2
+            ;;
+        -l | --log)
+            log="-d mmu,int,guest_errors -D jsix.log"
+            shift
             ;;
 		*)
             if [ -d "$1" ]; then
@@ -77,15 +84,12 @@ exec qemu-system-x86_64 \
 	-drive "if=pflash,format=raw,readonly,file=${assets}/ovmf/x64/ovmf_code.fd" \
 	-drive "if=pflash,format=raw,file=${build}/ovmf_vars.fd" \
 	-drive "format=raw,file=${build}/jsix.img" \
-	-device "isa-debug-exit,iobase=0xf4,iosize=0x04" \
 	-monitor telnet:localhost:45454,server,nowait \
 	-serial stdio \
 	-serial telnet:localhost:45455,server,nowait \
 	-smp "${smp}" \
-	-m 512 \
-	-d mmu,int,guest_errors \
-	-D jsix.log \
+	-m 4096 \
 	-cpu "${cpu}" \
 	-M q35 \
 	-no-reboot \
-	$gfx $vga $kvm $debug
+	$isaexit $log $gfx $vga $kvm $debug