feat(versal-net): add jtag dcc support

Add support for JTAG Debug Communication Channel(DCC), using the dcc
console driver, for Versal NET platform.
UART0/UART1 is not configured when the JTAG DCC is used as console for
the platform.
Though DCC is not using any UART, VERSAL_NET_UART_BASE needs
to be defined in the platform code. If its not defined, build errors
are observed.
Now VERSAL_NET_UART_BASE by default points to UART0 base.
Check for valid console(pl011, pl011_0, pl011_1, dcc) is
being done in the platform makefile, the error condition in
setting the value of VERSAL_NET_UART_BASE is redundant, thus the error
message is removed from the code.

Change-Id: I1085433055abea13526230cff4d4183ff7a01477
Signed-off-by: Akshay Belsare <akshay.belsare@amd.com>

4 files changed, 35 insertions, 16 deletions

diff --git a/docs/plat/xilinx-versal-net.rst b/docs/plat/xilinx-versal-net.rst
index 5d2e663e5..5d0463943 100644
--- a/docs/plat/xilinx-versal-net.rst
+++ b/docs/plat/xilinx-versal-net.rst
@@ -14,6 +14,11 @@ To build:
 make RESET_TO_BL31=1 CROSS_COMPILE=aarch64-none-elf- PLAT=versal_net bl31
 ```
 
+To build TF-A for JTAG DCC console:
+```bash
+make RESET_TO_BL31=1 CROSS_COMPILE=aarch64-none-elf- PLAT=versal_net VERSAL_NET_CONSOLE=dcc bl31
+```
+
 Xilinx Versal NET platform specific build options
 -------------------------------------------------
 
@@ -23,8 +28,9 @@ Xilinx Versal NET platform specific build options
 *   `VERSAL_NET_BL32_MEM_SIZE`: Specifies the size of the memory region of the bl32 binary.
 
 *   `VERSAL_NET_CONSOLE`: Select the console driver. Options:
-    -   `pl011`, `pl011_0`: ARM pl011 UART 0
+    -   `pl011`, `pl011_0`: ARM pl011 UART 0 (default)
     -   `pl011_1`         : ARM pl011 UART 1
+    -   `dcc`             : JTAG Debug Communication Channel(DCC)
 
 *   `TFA_NO_PM` : Platform Management support.
     -    0 : Enable Platform Management (Default)
diff --git a/plat/xilinx/versal_net/bl31_versal_net_setup.c b/plat/xilinx/versal_net/bl31_versal_net_setup.c
index c9942d6a5..2a073b01e 100644
--- a/plat/xilinx/versal_net/bl31_versal_net_setup.c
+++ b/plat/xilinx/versal_net/bl31_versal_net_setup.c
@@ -1,7 +1,7 @@
 /*
  * Copyright (c) 2018-2020, ARM Limited and Contributors. All rights reserved.
  * Copyright (c) 2018-2022, Xilinx, Inc. All rights reserved.
- * Copyright (C) 2022, Advanced Micro Devices, Inc. All rights reserved.
+ * Copyright (C) 2022-2023, Advanced Micro Devices, Inc. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -14,6 +14,7 @@
 #include <common/debug.h>
 #include <common/fdt_fixup.h>
 #include <common/fdt_wrappers.h>
+#include <drivers/arm/dcc.h>
 #include <drivers/arm/pl011.h>
 #include <drivers/console.h>
 #include <lib/mmio.h>
@@ -28,7 +29,6 @@
 
 static entry_point_info_t bl32_image_ep_info;
 static entry_point_info_t bl33_image_ep_info;
-static console_t versal_net_runtime_console;
 
 /*
  * Return a pointer to the 'entry_point_info' structure of the next image for
@@ -95,16 +95,28 @@ void bl31_early_platform_setup2(u_register_t arg0, u_register_t arg1,
 		panic();
 	}
 
-	/* Initialize the console to provide early debug support */
-	rc = console_pl011_register(VERSAL_NET_UART_BASE, uart_clock,
+	if (VERSAL_NET_CONSOLE_IS(pl011_0) || VERSAL_NET_CONSOLE_IS(pl011_1)) {
+		static console_t versal_net_runtime_console;
+
+		/* Initialize the console to provide early debug support */
+		rc = console_pl011_register(VERSAL_NET_UART_BASE, uart_clock,
 				    VERSAL_NET_UART_BAUDRATE,
 				    &versal_net_runtime_console);
-	if (rc == 0) {
-		panic();
-	}
+		if (rc == 0) {
+			panic();
+		}
 
-	console_set_scope(&versal_net_runtime_console, CONSOLE_FLAG_BOOT |
-			  CONSOLE_FLAG_RUNTIME);
+		console_set_scope(&versal_net_runtime_console, CONSOLE_FLAG_BOOT |
+				CONSOLE_FLAG_RUNTIME);
+	} else if (VERSAL_NET_CONSOLE_IS(dcc)) {
+		/* Initialize the dcc console for debug.
+		 * dcc is over jtag and does not configures uart0 or uart1.
+		 */
+		rc = console_dcc_register();
+		if (rc == 0) {
+			panic();
+		}
+	}
 
 	NOTICE("TF-A running on Xilinx %s %d.%d\n", board_name_decode(),
 	       platform_version / 10U, platform_version % 10U);
diff --git a/plat/xilinx/versal_net/include/versal_net_def.h b/plat/xilinx/versal_net/include/versal_net_def.h
index 14e63d575..9d1b7c278 100644
--- a/plat/xilinx/versal_net/include/versal_net_def.h
+++ b/plat/xilinx/versal_net/include/versal_net_def.h
@@ -1,7 +1,7 @@
 /*
  * Copyright (c) 2022, ARM Limited and Contributors. All rights reserved.
  * Copyright (c) 2021-2022, Xilinx, Inc. All rights reserved.
- * Copyright (C) 2022, Advanced Micro Devices, Inc. All rights reserved.
+ * Copyright (C) 2022-2023, Advanced Micro Devices, Inc. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -24,6 +24,7 @@
 #define VERSAL_NET_CONSOLE_ID_pl011	U(1)
 #define VERSAL_NET_CONSOLE_ID_pl011_0	U(1)
 #define VERSAL_NET_CONSOLE_ID_pl011_1	U(2)
+#define VERSAL_NET_CONSOLE_ID_dcc	U(3)
 
 #define VERSAL_NET_CONSOLE_IS(con)	(VERSAL_NET_CONSOLE_ID_ ## con == VERSAL_NET_CONSOLE)
 
@@ -142,12 +143,11 @@
 
 #define VERSAL_NET_UART_BAUDRATE	115200
 
-#if VERSAL_NET_CONSOLE_IS(pl011) || VERSAL_NET_CONSOLE_IS(pl011_0)
-#define VERSAL_NET_UART_BASE		VERSAL_NET_UART0_BASE
-#elif VERSAL_NET_CONSOLE_IS(pl011_1)
+#if VERSAL_NET_CONSOLE_IS(pl011_1)
 #define VERSAL_NET_UART_BASE		VERSAL_NET_UART1_BASE
 #else
-# error "invalid VERSAL_NET_CONSOLE"
+/* Default console is UART0 */
+#define VERSAL_NET_UART_BASE            VERSAL_NET_UART0_BASE
 #endif
 
 #define PLAT_VERSAL_NET_CRASH_UART_BASE		VERSAL_NET_UART_BASE
diff --git a/plat/xilinx/versal_net/platform.mk b/plat/xilinx/versal_net/platform.mk
index 622ae98c2..28e329519 100644
--- a/plat/xilinx/versal_net/platform.mk
+++ b/plat/xilinx/versal_net/platform.mk
@@ -53,7 +53,7 @@ USE_COHERENT_MEM := 0
 HW_ASSISTED_COHERENCY := 1
 
 VERSAL_NET_CONSOLE	?=	pl011
-ifeq (${VERSAL_NET_CONSOLE}, $(filter ${VERSAL_NET_CONSOLE},pl011 pl011_0 pl011_1))
+ifeq (${VERSAL_NET_CONSOLE}, $(filter ${VERSAL_NET_CONSOLE},pl011 pl011_0 pl011_1 dcc))
 else
   $(error Please define VERSAL_NET_CONSOLE)
 endif
@@ -72,6 +72,7 @@ include lib/xlat_tables_v2/xlat_tables.mk
 include lib/libfdt/libfdt.mk
 
 PLAT_BL_COMMON_SOURCES	:=	\
+				drivers/arm/dcc/dcc_console.c			\
 				drivers/delay_timer/delay_timer.c		\
 				drivers/delay_timer/generic_delay_timer.c	\
 				${GICV3_SOURCES}				\