Merge pull request #1805 from antonio-nino-diaz-arm/an/generic-timer

drivers: generic_delay_timer: Assert presence of Generic Timer

drivers/delay_timer/generic_delay_timer.c

 /*
- * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
 #include <assert.h>
 
+#include <arch_features.h>
 #include <arch_helpers.h>
 #include <common/bl_common.h>
 #include <common/debug.h>
@@ -43,6 +44,8 @@ void generic_delay_timer_init_args(uint32_t mult, uint32_t div)
 
 void generic_delay_timer_init(void)
 {
+	assert(is_armv7_gentimer_present());
+
 	/* Value in ticks */
 	unsigned int mult = MHZ_TICKS_PER_SEC;
 

include/arch/aarch32/arch.h

@@ -114,6 +114,8 @@
 #define ID_PFR1_VIRTEXT_MASK	U(0xf)
 #define GET_VIRT_EXT(id)	(((id) >> ID_PFR1_VIRTEXT_SHIFT) \
 				 & ID_PFR1_VIRTEXT_MASK)
+#define ID_PFR1_GENTIMER_SHIFT	U(16)
+#define ID_PFR1_GENTIMER_MASK	U(0xf)
 #define ID_PFR1_GIC_SHIFT	U(28)
 #define ID_PFR1_GIC_MASK	U(0xf)
 

include/arch/aarch32/arch_features.h

@@ -11,6 +11,12 @@
 
 #include <arch_helpers.h>
 
+static inline bool is_armv7_gentimer_present(void)
+{
+	return ((read_id_pfr1() >> ID_PFR1_GENTIMER_SHIFT) &
+		ID_PFR1_GENTIMER_MASK) != 0U;
+}
+
 static inline bool is_armv8_2_ttcnp_present(void)
 {
 	return ((read_id_mmfr4() >> ID_MMFR4_CNP_SHIFT) &

include/arch/aarch64/arch_features.h

@@ -11,6 +11,12 @@
 
 #include <arch_helpers.h>
 
+static inline bool is_armv7_gentimer_present(void)
+{
+	/* The Generic Timer is always present in an ARMv8-A implementation */
+	return true;
+}
+
 static inline bool is_armv8_2_ttcnp_present(void)
 {
 	return ((read_id_aa64mmfr2_el1() >> ID_AA64MMFR2_EL1_CNP_SHIFT) &