diff --git a/default-configs/ppc-softmmu.mak b/default-configs/ppc-softmmu.mak
index f5cd0bdcc0..f380ca47d7 100644
--- a/default-configs/ppc-softmmu.mak
+++ b/default-configs/ppc-softmmu.mak
@@ -41,6 +41,7 @@ CONFIG_I8259=y
 CONFIG_XILINX=y
 CONFIG_XILINX_ETHLITE=y
 CONFIG_OPENPIC=y
+CONFIG_PREP=y
 CONFIG_E500=y
 CONFIG_OPENPIC_KVM=$(and $(CONFIG_E500),$(CONFIG_KVM))
 # For PReP
diff --git a/default-configs/ppc64-softmmu.mak b/default-configs/ppc64-softmmu.mak
index fb34a9b074..fcc04529b4 100644
--- a/default-configs/ppc64-softmmu.mak
+++ b/default-configs/ppc64-softmmu.mak
@@ -42,6 +42,7 @@ CONFIG_XILINX=y
 CONFIG_XILINX_ETHLITE=y
 CONFIG_OPENPIC=y
 CONFIG_PSERIES=y
+CONFIG_PREP=y
 CONFIG_E500=y
 CONFIG_OPENPIC_KVM=$(and $(CONFIG_E500),$(CONFIG_KVM))
 # For pSeries
diff --git a/default-configs/ppcemb-softmmu.mak b/default-configs/ppcemb-softmmu.mak
index 4411203a9a..fdf1e14a95 100644
--- a/default-configs/ppcemb-softmmu.mak
+++ b/default-configs/ppcemb-softmmu.mak
@@ -10,11 +10,9 @@ CONFIG_VGA=y
 CONFIG_VGA_PCI=y
 CONFIG_SERIAL=y
 CONFIG_I8254=y
-CONFIG_PCKBD=y
 CONFIG_FDC=y
 CONFIG_I8257=y
 CONFIG_OPENPIC=y
-CONFIG_PREP_PCI=y
 CONFIG_MACIO=y
 CONFIG_CUDA=y
 CONFIG_ADB=y
@@ -38,6 +36,3 @@ CONFIG_XILINX_ETHLITE=y
 CONFIG_OPENPIC=y
 CONFIG_E500=y
 CONFIG_OPENPIC_KVM=$(and $(CONFIG_E500),$(CONFIG_KVM))
-# For PReP
-CONFIG_MC146818RTC=y
-CONFIG_ISA_TESTDEV=y
diff --git a/hw/ppc/Makefile.objs b/hw/ppc/Makefile.objs
index 7a1cd5d89e..2dd5284532 100644
--- a/hw/ppc/Makefile.objs
+++ b/hw/ppc/Makefile.objs
@@ -8,7 +8,7 @@ obj-$(CONFIG_PSERIES) += spapr_pci.o
 obj-y += ppc405_boards.o ppc4xx_devs.o ppc405_uc.o ppc440_bamboo.o
 obj-y += ppc4xx_pci.o
 # PReP
-obj-y += prep.o
+obj-$(CONFIG_PREP) += prep.o
 # OldWorld PowerMac
 obj-y += mac_oldworld.o
 # NewWorld PowerMac