Merge pull request #885 from antonio-nino-diaz-arm/an/console-flush

Implement console_flush()

25 files changed, 319 insertions, 30 deletions

diff --git a/bl1/bl1_main.c b/bl1/bl1_main.c
index 90c06afe..89664cd0 100644
--- a/bl1/bl1_main.c
+++ b/bl1/bl1_main.c
@@ -34,6 +34,7 @@
 #include <auth_mod.h>
 #include <bl1.h>
 #include <bl_common.h>
+#include <console.h>
 #include <debug.h>
 #include <errata_report.h>
 #include <platform.h>
@@ -166,6 +167,8 @@ void bl1_main(void)
 		NOTICE("BL1-FWU: *******FWU Process Started*******\n");
 
 	bl1_prepare_next_image(image_id);
+
+	console_flush();
 }
 
 /*******************************************************************************
diff --git a/bl2/bl2_main.c b/bl2/bl2_main.c
index 514c0053..d187f2e3 100644
--- a/bl2/bl2_main.c
+++ b/bl2/bl2_main.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -32,6 +32,7 @@
 #include <auth_mod.h>
 #include <bl1.h>
 #include <bl_common.h>
+#include <console.h>
 #include <debug.h>
 #include <platform.h>
 #include "bl2_private.h"
@@ -69,6 +70,8 @@ void bl2_main(void)
 	disable_mmu_icache_secure();
 #endif /* AARCH32 */
 
+	console_flush();
+
 	/*
 	 * Run next BL image via an SMC to BL1. Information on how to pass
 	 * control to the BL32 (if present) and BL33 software images will
diff --git a/bl2u/bl2u_main.c b/bl2u/bl2u_main.c
index 515ddfb7..3ed5be73 100644
--- a/bl2u/bl2u_main.c
+++ b/bl2u/bl2u_main.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -34,6 +34,7 @@
 #include <auth_mod.h>
 #include <bl_common.h>
 #include <bl1.h>
+#include <console.h>
 #include <debug.h>
 #include <platform.h>
 #include <platform_def.h>
@@ -63,6 +64,8 @@ void bl2u_main(void)
 	/* Perform platform setup in BL2U after loading SCP_BL2U */
 	bl2u_platform_setup();
 
+	console_flush();
+
 	/*
 	 * Indicate that BL2U is done and resume back to
 	 * normal world via an SMC to BL1.
diff --git a/bl31/aarch64/crash_reporting.S b/bl31/aarch64/crash_reporting.S
index 8e603862..c6d5c6c3 100644
--- a/bl31/aarch64/crash_reporting.S
+++ b/bl31/aarch64/crash_reporting.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2014-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -349,6 +349,8 @@ func do_crash_reporting
 	/* Print some platform registers */
 	plat_crash_print_regs
 
+	bl	plat_crash_console_flush
+
 	/* Done reporting */
 	no_ret	plat_panic_handler
 endfunc do_crash_reporting
diff --git a/bl31/bl31_main.c b/bl31/bl31_main.c
index 85b3ea1e..c74b72b7 100644
--- a/bl31/bl31_main.c
+++ b/bl31/bl31_main.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -33,6 +33,7 @@
 #include <assert.h>
 #include <bl_common.h>
 #include <bl31.h>
+#include <console.h>
 #include <context_mgmt.h>
 #include <debug.h>
 #include <platform.h>
@@ -129,6 +130,8 @@ void bl31_main(void)
 	 */
 	bl31_prepare_next_image_entry();
 
+	console_flush();
+
 	/*
 	 * Perform any platform specific runtime setup prior to cold boot exit
 	 * from BL31
diff --git a/common/aarch32/debug.S b/common/aarch32/debug.S
index ecf9faff..77298a12 100644
--- a/common/aarch32/debug.S
+++ b/common/aarch32/debug.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -70,9 +70,12 @@ func do_panic
 	/* Print new line */
 	ldr	r4, =panic_end
 	bl	asm_print_str
+
+	bl	plat_crash_console_flush
+
 1:
 	mov	lr, r6
-	b	plat_panic_handler
+	no_ret	plat_panic_handler
 endfunc do_panic
 
 	/***********************************************************
@@ -140,6 +143,9 @@ dec_print_loop:
 	udiv	r5, r5, r6			/* Reduce divisor */
 	cmp	r5, #0
 	bne	dec_print_loop
+
+	bl	plat_crash_console_flush
+
 1:
 	no_ret	plat_panic_handler
 endfunc asm_assert
diff --git a/common/aarch64/debug.S b/common/aarch64/debug.S
index 9dd53ca9..fb6924ea 100644
--- a/common/aarch64/debug.S
+++ b/common/aarch64/debug.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2014-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -96,8 +96,9 @@ func asm_assert
 	b.ne	_assert_loop
 	mov	x4, x6
 	asm_print_line_dec
+	bl	plat_crash_console_flush
 _assert_loop:
-	b	_assert_loop
+	no_ret	plat_panic_handler
 endfunc asm_assert
 #endif
 
@@ -187,6 +188,8 @@ el3_panic:
 	sub	x4, x4, #4
 	bl	asm_print_hex
 
+	bl	plat_crash_console_flush
+
 _panic_handler:
 	/* Pass to plat_panic_handler the address from where el3_panic was
 	 * called, not the address of the call from el3_panic. */
diff --git a/docs/porting-guide.md b/docs/porting-guide.md
index 690f307a..0189ec40 100644
--- a/docs/porting-guide.md
+++ b/docs/porting-guide.md
@@ -2242,6 +2242,17 @@ designated crash console. It must only use general purpose registers x1 and
 x2 to do its work. The parameter and the return value are in general purpose
 register x0.
 
+### Function : plat_crash_console_flush
+
+    Argument : void
+    Return   : int
+
+This API is used by the crash reporting mechanism to force write of all buffered
+data on the designated crash console. It should only use general purpose
+registers x0 and x1 to do its work. The return value is 0 on successful
+completion; otherwise the return value is -1.
+
+
 4.  Build flags
 ---------------
 
diff --git a/drivers/arm/pl011/aarch32/pl011_console.S b/drivers/arm/pl011/aarch32/pl011_console.S
index 5b735283..6c4046a6 100644
--- a/drivers/arm/pl011/aarch32/pl011_console.S
+++ b/drivers/arm/pl011/aarch32/pl011_console.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -40,6 +40,7 @@
 	.globl	console_core_init
 	.globl	console_core_putc
 	.globl	console_core_getc
+	.globl	console_core_flush
 
 
 	/* -----------------------------------------------
@@ -158,3 +159,29 @@ getc_error:
 	mov	r0, #-1
 	bx	lr
 endfunc console_core_getc
+
+	/* ---------------------------------------------
+	 * int console_core_flush(uintptr_t base_addr)
+	 * Function to force a write of all buffered
+	 * data that hasn't been output.
+	 * In : r0 - console base address
+	 * Out : return -1 on error else return 0.
+	 * Clobber list : r0, r1
+	 * ---------------------------------------------
+	 */
+func console_core_flush
+	cmp	r0, #0
+	beq	flush_error
+
+1:
+	/* Loop while the transmit FIFO is busy */
+	ldr	r1, [r0, #UARTFR]
+	tst	r1, #PL011_UARTFR_BUSY
+	bne	1b
+
+	mov	r0, #0
+	bx	lr
+flush_error:
+	mov	r0, #-1
+	bx	lr
+endfunc console_core_flush
diff --git a/drivers/arm/pl011/aarch64/pl011_console.S b/drivers/arm/pl011/aarch64/pl011_console.S
index 11e3df77..11030089 100644
--- a/drivers/arm/pl011/aarch64/pl011_console.S
+++ b/drivers/arm/pl011/aarch64/pl011_console.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -41,6 +41,7 @@
 	.globl	console_core_init
 	.globl	console_core_putc
 	.globl	console_core_getc
+	.globl	console_core_flush
 
 
 	/* -----------------------------------------------
@@ -151,3 +152,27 @@ getc_error:
 	mov	w0, #-1
 	ret
 endfunc console_core_getc
+
+	/* ---------------------------------------------
+	 * int console_core_flush(uintptr_t base_addr)
+	 * Function to force a write of all buffered
+	 * data that hasn't been output.
+	 * In : x0 - console base address
+	 * Out : return -1 on error else return 0.
+	 * Clobber list : x0, x1
+	 * ---------------------------------------------
+	 */
+func console_core_flush
+	cbz	x0, flush_error
+
+1:
+	/* Loop until the transmit FIFO is empty */
+	ldr	w1, [x0, #UARTFR]
+	tbnz	w1, #PL011_UARTFR_BUSY_BIT, 1b
+
+	mov	w0, #0
+	ret
+flush_error:
+	mov	w0, #-1
+	ret
+endfunc console_core_flush
diff --git a/drivers/cadence/uart/aarch64/cdns_console.S b/drivers/cadence/uart/aarch64/cdns_console.S
index 2c7960d8..e16646e8 100644
--- a/drivers/cadence/uart/aarch64/cdns_console.S
+++ b/drivers/cadence/uart/aarch64/cdns_console.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -31,9 +31,10 @@
 #include <asm_macros.S>
 #include <cadence/cdns_uart.h>
 
-        .globl  console_core_init
-        .globl  console_core_putc
-        .globl  console_core_getc
+	.globl  console_core_init
+	.globl  console_core_putc
+	.globl  console_core_getc
+	.globl	console_core_flush
 
 	/* -----------------------------------------------
 	 * int console_core_init(unsigned long base_addr,
@@ -125,3 +126,18 @@ getc_error:
 	mov	w0, #-1
 	ret
 endfunc console_core_getc
+
+	/* ---------------------------------------------
+	 * int console_core_flush(uintptr_t base_addr)
+	 * Function to force a write of all buffered
+	 * data that hasn't been output.
+	 * In : x0 - console base address
+	 * Out : return -1 on error else return 0.
+	 * Clobber list : x0, x1
+	 * ---------------------------------------------
+	 */
+func console_core_flush
+	/* Placeholder */
+	mov	w0, #0
+	ret
+endfunc console_core_flush
diff --git a/drivers/console/aarch32/console.S b/drivers/console/aarch32/console.S
index 29933452..6f85a21f 100644
--- a/drivers/console/aarch32/console.S
+++ b/drivers/console/aarch32/console.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -33,6 +33,7 @@
 	.globl	console_uninit
 	.globl	console_putc
 	.globl	console_getc
+	.globl	console_flush
 
 	/*
 	 *  The console base is in the data section and not in .bss
@@ -112,3 +113,18 @@ func console_getc
 	ldr	r0, [r1]
 	b	console_core_getc
 endfunc console_getc
+
+	/* ---------------------------------------------
+	 * int console_flush(void)
+	 * Function to force a write of all buffered
+	 * data that hasn't been output. It returns 0
+	 * upon successful completion, otherwise it
+	 * returns -1.
+	 * Clobber list : r0, r1
+	 * ---------------------------------------------
+	 */
+func console_flush
+	ldr	r1, =console_base
+	ldr	r0, [r1]
+	b	console_core_flush
+endfunc console_flush
diff --git a/drivers/console/aarch32/skeleton_console.S b/drivers/console/aarch32/skeleton_console.S
index 383874e6..0b60bc75 100644
--- a/drivers/console/aarch32/skeleton_console.S
+++ b/drivers/console/aarch32/skeleton_console.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -38,6 +38,7 @@
 	.globl	console_core_init
 	.globl	console_core_putc
 	.globl	console_core_getc
+	.globl	console_core_flush
 
 	/* -----------------------------------------------
 	 * int console_core_init(uintptr_t base_addr,
@@ -109,3 +110,23 @@ getc_error:
 	mov	r0, #-1
 	bx	lr
 endfunc console_core_getc
+
+	/* ---------------------------------------------
+	 * int console_core_flush(uintptr_t base_addr)
+	 * Function to force a write of all buffered
+	 * data that hasn't been output.
+	 * In : r0 - console base address
+	 * Out : return -1 on error else return 0.
+	 * Clobber list : r0, r1
+	 * ---------------------------------------------
+	 */
+func console_core_flush
+	cmp	r0, #0
+	beq	flush_error
+	/* Insert implementation here */
+	mov	r0, #0
+	bx	lr
+flush_error:
+	mov	r0, #-1
+	bx	lr
+endfunc console_core_flush
diff --git a/drivers/console/aarch64/console.S b/drivers/console/aarch64/console.S
index bdd5f4c3..cd6579cf 100644
--- a/drivers/console/aarch64/console.S
+++ b/drivers/console/aarch64/console.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -33,6 +33,7 @@
 	.globl	console_uninit
 	.globl	console_putc
 	.globl	console_getc
+	.globl	console_flush
 
 	/*
 	 *  The console base is in the data section and not in .bss
@@ -111,3 +112,18 @@ func console_getc
 	ldr	x0, [x1, :lo12:console_base]
 	b	console_core_getc
 endfunc console_getc
+
+	/* ---------------------------------------------
+	 * int console_flush(void)
+	 * Function to force a write of all buffered
+	 * data that hasn't been output. It returns 0
+	 * upon successful completion, otherwise it
+	 * returns -1.
+	 * Clobber list : x0, x1
+	 * ---------------------------------------------
+	 */
+func console_flush
+	adrp	x1, console_base
+	ldr	x0, [x1, :lo12:console_base]
+	b	console_core_flush
+endfunc console_flush
diff --git a/drivers/console/aarch64/skeleton_console.S b/drivers/console/aarch64/skeleton_console.S
index 1583ee7d..01a42672 100644
--- a/drivers/console/aarch64/skeleton_console.S
+++ b/drivers/console/aarch64/skeleton_console.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -38,6 +38,7 @@
 	.globl	console_core_init
 	.globl	console_core_putc
 	.globl	console_core_getc
+	.globl	console_core_flush
 
 	/* -----------------------------------------------
 	 * int console_core_init(uintptr_t base_addr,
@@ -104,3 +105,22 @@ getc_error:
 	mov	w0, #-1
 	ret
 endfunc console_core_getc
+
+	/* ---------------------------------------------
+	 * int console_core_flush(uintptr_t base_addr)
+	 * Function to force a write of all buffered
+	 * data that hasn't been output.
+	 * In : x0 - console base address
+	 * Out : return -1 on error else return 0.
+	 * Clobber list : x0, x1
+	 * ---------------------------------------------
+	 */
+func console_core_flush
+	cbz	x0, flush_error
+	/* Insert implementation here */
+	mov	w0, #0
+	ret
+flush_error:
+	mov	w0, #-1
+	ret
+endfunc console_core_flush
diff --git a/drivers/ti/uart/aarch64/16550_console.S b/drivers/ti/uart/aarch64/16550_console.S
index 84664829..489fcbea 100644
--- a/drivers/ti/uart/aarch64/16550_console.S
+++ b/drivers/ti/uart/aarch64/16550_console.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -35,6 +35,7 @@
 	.globl	console_core_init
 	.globl	console_core_putc
 	.globl	console_core_getc
+	.globl	console_core_flush
 
 	/* -----------------------------------------------
 	 * int console_core_init(unsigned long base_addr,
@@ -153,3 +154,18 @@ getc_error:
 	mov	w0, #-1
 	ret
 endfunc console_core_getc
+
+	/* ---------------------------------------------
+	 * int console_core_flush(uintptr_t base_addr)
+	 * Function to force a write of all buffered
+	 * data that hasn't been output.
+	 * In : x0 - console base address
+	 * Out : return -1 on error else return 0.
+	 * Clobber list : x0, x1
+	 * ---------------------------------------------
+	 */
+func console_core_flush
+	/* Placeholder */
+	mov	w0, #0
+	ret
+endfunc console_core_flush
diff --git a/include/drivers/console.h b/include/drivers/console.h
index 69ad0bd7..e6e3a1cb 100644
--- a/include/drivers/console.h
+++ b/include/drivers/console.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -38,6 +38,7 @@ int console_init(uintptr_t base_addr,
 void console_uninit(void);
 int console_putc(int c);
 int console_getc(void);
+int console_flush(void);
 
 #endif /* __CONSOLE_H__ */
 
diff --git a/include/plat/common/platform.h b/include/plat/common/platform.h
index f13b30d8..ddb1cab1 100644
--- a/include/plat/common/platform.h
+++ b/include/plat/common/platform.h
@@ -100,6 +100,7 @@ uintptr_t plat_get_my_stack(void);
 void plat_report_exception(unsigned int exception_type);
 int plat_crash_console_init(void);
 int plat_crash_console_putc(int c);
+int plat_crash_console_flush(void);
 void plat_error_handler(int err) __dead2;
 void plat_panic_handler(void) __dead2;
 
diff --git a/lib/psci/psci_system_off.c b/lib/psci/psci_system_off.c
index de9ec643..eb3e7fbc 100644
--- a/lib/psci/psci_system_off.c
+++ b/lib/psci/psci_system_off.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2014-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -31,6 +31,7 @@
 #include <stddef.h>
 #include <arch_helpers.h>
 #include <assert.h>
+#include <console.h>
 #include <debug.h>
 #include <platform.h>
 #include "psci_private.h"
@@ -46,6 +47,8 @@ void psci_system_off(void)
 		psci_spd_pm->svc_system_off();
 	}
 
+	console_flush();
+
 	/* Call the platform specific hook */
 	psci_plat_pm_ops->system_off();
 
@@ -63,6 +66,8 @@ void psci_system_reset(void)
 		psci_spd_pm->svc_system_reset();
 	}
 
+	console_flush();
+
 	/* Call the platform specific hook */
 	psci_plat_pm_ops->system_reset();
 
diff --git a/lib/stdlib/assert.c b/lib/stdlib/assert.c
index 90a1afe5..3486e50b 100644
--- a/lib/stdlib/assert.c
+++ b/lib/stdlib/assert.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2014, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -28,7 +28,9 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <console.h>
 #include <debug.h>
+#include <platform.h>
 
 /*
  * This is a basic implementation. This could be improved.
@@ -37,5 +39,8 @@ void __assert (const char *function, const char *file, unsigned int line,
 		const char *assertion)
 {
 	tf_printf("ASSERT: %s <%d> : %s\n", function, line, assertion);
-	while(1);
+
+	console_flush();
+
+	plat_panic_handler();
 }
diff --git a/plat/arm/common/aarch32/arm_helpers.S b/plat/arm/common/aarch32/arm_helpers.S
index 5d238ecb..51e5ee9a 100644
--- a/plat/arm/common/aarch32/arm_helpers.S
+++ b/plat/arm/common/aarch32/arm_helpers.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -31,9 +31,10 @@
 #include <platform_def.h>
 
 	.weak	plat_arm_calc_core_pos
-	.weak	plat_crash_console_init
-	.weak	plat_crash_console_putc
 	.weak	plat_my_core_pos
+	.globl	plat_crash_console_init
+	.globl	plat_crash_console_putc
+	.globl	plat_crash_console_flush
 
 	/* -----------------------------------------------------
 	 *  unsigned int plat_my_core_pos(void)
@@ -85,3 +86,16 @@ func plat_crash_console_putc
 	ldr	r1, =PLAT_ARM_CRASH_UART_BASE
 	b	console_core_putc
 endfunc plat_crash_console_putc
+
+	/* ---------------------------------------------
+	 * int plat_crash_console_flush()
+	 * Function to force a write of all buffered
+	 * data that hasn't been output.
+	 * Out : return -1 on error else return 0.
+	 * Clobber list : r0 - r1
+	 * ---------------------------------------------
+	 */
+func plat_crash_console_flush
+	ldr	r1, =PLAT_ARM_CRASH_UART_BASE
+	b	console_core_flush
+endfunc plat_crash_console_flush
diff --git a/plat/arm/common/aarch64/arm_helpers.S b/plat/arm/common/aarch64/arm_helpers.S
index d782020a..60ff834a 100644
--- a/plat/arm/common/aarch64/arm_helpers.S
+++ b/plat/arm/common/aarch64/arm_helpers.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -34,6 +34,7 @@
 	.weak	plat_my_core_pos
 	.globl	plat_crash_console_init
 	.globl	plat_crash_console_putc
+	.globl	plat_crash_console_flush
 	.globl	platform_mem_init
 
 
@@ -88,6 +89,19 @@ func plat_crash_console_putc
 	b	console_core_putc
 endfunc plat_crash_console_putc
 
+	/* ---------------------------------------------
+	 * int plat_crash_console_flush()
+	 * Function to force a write of all buffered
+	 * data that hasn't been output.
+	 * Out : return -1 on error else return 0.
+	 * Clobber list : r0 - r1
+	 * ---------------------------------------------
+	 */
+func plat_crash_console_flush
+	mov_imm	x1, PLAT_ARM_CRASH_UART_BASE
+	b	console_core_flush
+endfunc plat_crash_console_flush
+
 	/* ---------------------------------------------------------------------
 	 * We don't need to carry out any memory initialization on ARM
 	 * platforms. The Secure RAM is accessible straight away.
diff --git a/plat/common/aarch32/platform_helpers.S b/plat/common/aarch32/platform_helpers.S
index 802e1fe6..357719bf 100644
--- a/plat/common/aarch32/platform_helpers.S
+++ b/plat/common/aarch32/platform_helpers.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -31,6 +31,9 @@
 #include <arch.h>
 #include <asm_macros.S>
 
+	.weak	plat_crash_console_init
+	.weak	plat_crash_console_putc
+	.weak	plat_crash_console_flush
 	.weak	plat_reset_handler
 	.weak	plat_disable_acp
 	.weak	platform_mem_init
@@ -41,6 +44,35 @@
 	 * each platform.
 	 * -----------------------------------------------------
 	 */
+func plat_crash_console_init
+	mov	r0, #0
+	bx	lr
+endfunc plat_crash_console_init
+
+	/* -----------------------------------------------------
+	 * Placeholder function which should be redefined by
+	 * each platform.
+	 * -----------------------------------------------------
+	 */
+func plat_crash_console_putc
+	bx	lr
+endfunc plat_crash_console_putc
+
+	/* -----------------------------------------------------
+	 * Placeholder function which should be redefined by
+	 * each platform.
+	 * -----------------------------------------------------
+	 */
+func plat_crash_console_flush
+	mov	r0, #0
+	bx	lr
+endfunc plat_crash_console_flush
+
+	/* -----------------------------------------------------
+	 * Placeholder function which should be redefined by
+	 * each platform.
+	 * -----------------------------------------------------
+	 */
 func plat_reset_handler
 	bx	lr
 endfunc plat_reset_handler
diff --git a/plat/common/aarch64/platform_helpers.S b/plat/common/aarch64/platform_helpers.S
index 68bda223..ce477384 100644
--- a/plat/common/aarch64/platform_helpers.S
+++ b/plat/common/aarch64/platform_helpers.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -35,6 +35,7 @@
 	.weak	plat_report_exception
 	.weak	plat_crash_console_init
 	.weak	plat_crash_console_putc
+	.weak	plat_crash_console_flush
 	.weak	plat_reset_handler
 	.weak	plat_disable_acp
 	.weak	bl1_plat_prepare_exit
@@ -98,6 +99,15 @@ endfunc plat_crash_console_putc
 
 	/* -----------------------------------------------------
 	 * Placeholder function which should be redefined by
+	 * each platform.
+	 * -----------------------------------------------------
+	 */
+func plat_crash_console_flush
+	ret
+endfunc plat_crash_console_flush
+
+	/* -----------------------------------------------------
+	 * Placeholder function which should be redefined by
 	 * each platform. This function should preserve x19 - x29.
 	 * -----------------------------------------------------
 	 */
diff --git a/plat/mediatek/common/drivers/uart/8250_console.S b/plat/mediatek/common/drivers/uart/8250_console.S
index 5b0ae6df..8da248c1 100644
--- a/plat/mediatek/common/drivers/uart/8250_console.S
+++ b/plat/mediatek/common/drivers/uart/8250_console.S
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -33,6 +33,7 @@
 	.globl	console_core_init
 	.globl	console_core_putc
 	.globl	console_core_getc
+	.globl	console_core_flush
 
 	/* -----------------------------------------------
 	 * int console_core_init(unsigned long base_addr,
@@ -170,3 +171,18 @@ getc_error:
 	mov	w0, #-1
 	ret
 endfunc console_core_getc
+
+	/* ---------------------------------------------
+	 * int console_core_flush(uintptr_t base_addr)
+	 * Function to force a write of all buffered
+	 * data that hasn't been output.
+	 * In : x0 - console base address
+	 * Out : return -1 on error else return 0.
+	 * Clobber list : x0, x1
+	 * ---------------------------------------------
+	 */
+func console_core_flush
+	/* Placeholder */
+	mov	w0, #0
+	ret
+endfunc console_core_flush