Add support for hardware rng

Author: twcook86

arch.mk

@@ -1128,9 +1128,12 @@ ifeq ($(TARGET),lpc55s69)
       -I$(MCUXPRESSO)/drivers/iap1 \
       -I$(MCUXPRESSO)/drivers/lpc_gpio \
       -I$(MCUXPRESSO)/drivers/lpc_iocon \
+      -I$(MCUXPRESSO)/drivers/rng_1 \
       -I$(MCUXPRESSO_CMSIS)/Include \
       -I$(MCUXPRESSO_CMSIS)/Core/Include
   CFLAGS+=-DCPU_$(MCUXPRESSO_CPU)
+  CFLAGS+=-DFSL_SDK_DISABLE_DRIVER_CLOCK_CONTROL=1
+  CFLAGS+=-DFSL_SDK_DISABLE_DRIVER_RESET_CONTROL=1
   CFLAGS+=-mcpu=cortex-m33 -DCORTEX_M33 -U__ARM_FEATURE_DSP
   LDFLAGS+=-mcpu=cortex-m33 -Wl,--no-warn-rwx-segments
   OBJS+=\
@@ -1140,6 +1143,9 @@ ifeq ($(TARGET),lpc55s69)
       $(MCUXPRESSO)/drivers/common/fsl_common_arm.o \
       $(MCUXPRESSO)/drivers/iap1/fsl_iap.o \
       $(MCUXPRESSO)/drivers/lpc_gpio/fsl_gpio.o
+  ifeq ($(WOLFCRYPT_TZ),1)
+    OBJS+=$(MCUXPRESSO)/drivers/rng_1/fsl_rng.o
+  endif
   ifeq ($(DEBUG_UART),1)
     OBJS+=\
       $(MCUXPRESSO_DRIVERS)/drivers/fsl_reset.o \

hal/lpc55s69.c

@@ -30,6 +30,7 @@
 #include "fsl_iap.h"
 #include "fsl_iocon.h"
 #include "fsl_reset.h"
+#include "fsl_rng.h"
 #include "fsl_usart.h"
 #include "loader.h"
 
@@ -166,6 +167,11 @@ int RAMFUNCTION hal_flash_is_erased_at(uint32_t address)
 #ifdef WOLFCRYPT_SECURE_MODE
 void hal_trng_init(void)
 {
+#ifdef __WOLFBOOT
+    CLOCK_EnableClock(kCLOCK_Rng);
+    RESET_PeripheralReset(kRNG_RST_SHIFT_RSTn);
+#endif
+    RNG_Init(RNG);
 }
 
 void hal_trng_fini(void)
@@ -174,8 +180,9 @@ void hal_trng_fini(void)
 
 int hal_trng_get_entropy(unsigned char *out, unsigned int len)
 {
-    (void)out;
-    (void)len;
+    if (RNG_GetRandomData(RNG, out, len) == kStatus_Success)
+        return 0;
+
     return -1;
 }
 #endif
@@ -222,6 +229,7 @@ void uart_init(void)
 
     /* attach 12 MHz clock to FLEXCOMM0 (debug console) */
     CLOCK_AttachClk(kFRO12M_to_FLEXCOMM0);
+    CLOCK_EnableClock(kCLOCK_FlexComm0);
     RESET_ClearPeripheralReset(kFC0_RST_SHIFT_RSTn);
 
     usart_config_t config;

test-app/Makefile

@@ -582,6 +582,9 @@ ifeq ($(TARGET),lpc55s69)
       $(MCUXPRESSO)/drivers/flexcomm/usart/fsl_usart.o \
       $(MCUXPRESSO)/drivers/iap1/fsl_iap.o \
       $(MCUXPRESSO)/drivers/lpc_gpio/fsl_gpio.o
+    ifeq ($(WOLFCRYPT_TZ),1)
+      APP_OBJS+=$(MCUXPRESSO)/drivers/rng_1/fsl_rng.o
+    endif
     ifeq (,$(findstring nosys.specs,$(LDFLAGS)))
       LDFLAGS+=--specs=nosys.specs
     endif