[PATCH] bsps: Add BSP_FLUSH_KERNEL_CHAR_OUTPUT option

[Sebastian Huber]

Make the kernel I/O output character device flushing configurable.  The
bsp_reset() function should reset the unit and do nothing else.
---
 bsps/aarch64/xilinx-zynqmp/console/console.c  |  3 ++-
 bsps/aarch64/xilinx-zynqmp/include/bsp.h      |  2 --
 .../console/console-config.c                  |  3 ++-
 bsps/arm/xilinx-zynqmp-rpu/include/bsp.h      |  2 --
 bsps/arm/xilinx-zynqmp-rpu/start/bspreset.c   |  3 ---
 .../xilinx-zynqmp/console/console-config.c    |  2 +-
 bsps/arm/xilinx-zynqmp/include/bsp.h          |  2 --
 bsps/arm/xilinx-zynqmp/start/bspreset.c       |  4 +---
 bsps/include/bsp/bootcard.h                   |  5 +++++
 bsps/shared/start/bspfatal-default.c          |  4 ++++
 spec/build/bsps/bspopts.yml                   |  2 ++
 spec/build/bsps/optflushkerncharout.yml       | 20 +++++++++++++++++++
 12 files changed, 37 insertions(+), 15 deletions(-)
 create mode 100644 spec/build/bsps/optflushkerncharout.yml

diff --git a/bsps/aarch64/xilinx-zynqmp/console/console.c b/bsps/aarch64/xilinx-zynqmp/console/console.c
index 9ce0b1da63..d1b2850952 100644
--- a/bsps/aarch64/xilinx-zynqmp/console/console.c
+++ b/bsps/aarch64/xilinx-zynqmp/console/console.c
@@ -41,6 +41,7 @@
 #include <rtems/termiostypes.h>
 
 #include <bsp/aarch64-mmu.h>
+#include <bsp/bootcard.h>
 #include <bsp/fdt.h>
 #include <bsp/irq.h>
 
@@ -234,7 +235,7 @@ rtems_status_code console_initialize(
   return RTEMS_SUCCESSFUL;
 }
 
-void zynqmp_debug_console_flush(void)
+void bsp_flush_kernel_char_output(void)
 {
   zynq_uart_reset_tx_flush(&zynqmp_uart_instances[BSP_CONSOLE_MINOR]);
 }
diff --git a/bsps/aarch64/xilinx-zynqmp/include/bsp.h b/bsps/aarch64/xilinx-zynqmp/include/bsp.h
index 0ccca8b196..d36abde415 100644
--- a/bsps/aarch64/xilinx-zynqmp/include/bsp.h
+++ b/bsps/aarch64/xilinx-zynqmp/include/bsp.h
@@ -86,8 +86,6 @@ BSP_START_TEXT_SECTION void zynqmp_setup_mmu_and_cache(void);
  */
 BSP_START_TEXT_SECTION void zynqmp_setup_secondary_cpu_mmu_and_cache( void );
 
-void zynqmp_debug_console_flush(void);
-
 uint32_t zynqmp_clock_i2c0(void);
 
 uint32_t zynqmp_clock_i2c1(void);
diff --git a/bsps/arm/xilinx-zynqmp-rpu/console/console-config.c b/bsps/arm/xilinx-zynqmp-rpu/console/console-config.c
index f52e008f2b..196b2dec58 100644
--- a/bsps/arm/xilinx-zynqmp-rpu/console/console-config.c
+++ b/bsps/arm/xilinx-zynqmp-rpu/console/console-config.c
@@ -35,6 +35,7 @@
 #include <rtems/sysinit.h>
 #include <rtems/termiostypes.h>
 
+#include <bsp/bootcard.h>
 #include <bsp/irq.h>
 #include <dev/serial/zynq-uart.h>
 
@@ -79,7 +80,7 @@ rtems_status_code console_initialize(
   return RTEMS_SUCCESSFUL;
 }
 
-void zynqmp_debug_console_flush(void)
+void bsp_flush_kernel_char_output(void)
 {
   zynq_uart_reset_tx_flush(&zynqmp_uart_instances[BSP_CONSOLE_MINOR]);
 }
diff --git a/bsps/arm/xilinx-zynqmp-rpu/include/bsp.h b/bsps/arm/xilinx-zynqmp-rpu/include/bsp.h
index e386bd4b26..060147967c 100644
--- a/bsps/arm/xilinx-zynqmp-rpu/include/bsp.h
+++ b/bsps/arm/xilinx-zynqmp-rpu/include/bsp.h
@@ -83,8 +83,6 @@ extern "C" {
  */
 BSP_START_TEXT_SECTION void zynqmp_setup_mpu_and_cache(void);
 
-void zynqmp_debug_console_flush(void);
-
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */
diff --git a/bsps/arm/xilinx-zynqmp-rpu/start/bspreset.c b/bsps/arm/xilinx-zynqmp-rpu/start/bspreset.c
index eecb4da838..a894f55f6e 100644
--- a/bsps/arm/xilinx-zynqmp-rpu/start/bspreset.c
+++ b/bsps/arm/xilinx-zynqmp-rpu/start/bspreset.c
@@ -30,13 +30,10 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <bsp.h>
 #include <bsp/bootcard.h>
 
 void bsp_reset(void)
 {
-  zynqmp_debug_console_flush();
-
   while (true) {
     /* Wait */
   }
diff --git a/bsps/arm/xilinx-zynqmp/console/console-config.c b/bsps/arm/xilinx-zynqmp/console/console-config.c
index eadd7f11a2..360d193ba2 100644
--- a/bsps/arm/xilinx-zynqmp/console/console-config.c
+++ b/bsps/arm/xilinx-zynqmp/console/console-config.c
@@ -81,7 +81,7 @@ rtems_status_code console_initialize(
   return RTEMS_SUCCESSFUL;
 }
 
-void zynqmp_debug_console_flush(void)
+void bsp_flush_kernel_char_output(void)
 {
   zynq_uart_reset_tx_flush(&zynqmp_uart_instances[BSP_CONSOLE_MINOR]);
 }
diff --git a/bsps/arm/xilinx-zynqmp/include/bsp.h b/bsps/arm/xilinx-zynqmp/include/bsp.h
index a08a5feee9..2785e4c2e0 100644
--- a/bsps/arm/xilinx-zynqmp/include/bsp.h
+++ b/bsps/arm/xilinx-zynqmp/include/bsp.h
@@ -79,8 +79,6 @@ extern "C" {
  */
 BSP_START_TEXT_SECTION void zynqmp_setup_mmu_and_cache(void);
 
-void zynqmp_debug_console_flush(void);
-
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */
diff --git a/bsps/arm/xilinx-zynqmp/start/bspreset.c b/bsps/arm/xilinx-zynqmp/start/bspreset.c
index b43b19b05f..ed2f4da83a 100644
--- a/bsps/arm/xilinx-zynqmp/start/bspreset.c
+++ b/bsps/arm/xilinx-zynqmp/start/bspreset.c
@@ -30,12 +30,10 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include <bsp.h>
+#include <bsp/bootcard.h>
 
 void bsp_reset(void)
 {
-  zynqmp_debug_console_flush();
-
   while (true) {
     /* Wait */
   }
diff --git a/bsps/include/bsp/bootcard.h b/bsps/include/bsp/bootcard.h
index 5f339d65f8..dfdc3ae7e0 100644
--- a/bsps/include/bsp/bootcard.h
+++ b/bsps/include/bsp/bootcard.h
@@ -94,6 +94,11 @@ struct Per_CPU_Control;
  */
 void bsp_start_on_secondary_processor(struct Per_CPU_Control *cpu_self);
 
+/**
+ * @brief Flushes the kernel I/O output character device provided by the BSP.
+ */
+void bsp_flush_kernel_char_output(void);
+
 /** @} */
 
 #ifdef __cplusplus
diff --git a/bsps/shared/start/bspfatal-default.c b/bsps/shared/start/bspfatal-default.c
index 557a0960fa..de3f414407 100644
--- a/bsps/shared/start/bspfatal-default.c
+++ b/bsps/shared/start/bspfatal-default.c
@@ -184,6 +184,10 @@ void bsp_fatal_extension(
     printk("\n");
   #endif
 
+  #if BSP_FLUSH_KERNEL_CHAR_OUTPUT
+    bsp_flush_kernel_char_output();
+  #endif
+
   /*
    *  Check both conditions -- if you want to ask for reboot, then
    *  you must have meant to reset the board.
diff --git a/spec/build/bsps/bspopts.yml b/spec/build/bsps/bspopts.yml
index 8128a56330..bdab4b72f3 100644
--- a/spec/build/bsps/bspopts.yml
+++ b/spec/build/bsps/bspopts.yml
@@ -29,6 +29,8 @@ links:
   uid: optincludes
 - role: build-dependency
   uid: optcflags
+- role: build-dependency
+  uid: optflushkerncharout
 - role: build-dependency
   uid: optlinkflags
 - role: build-dependency
diff --git a/spec/build/bsps/optflushkerncharout.yml b/spec/build/bsps/optflushkerncharout.yml
new file mode 100644
index 0000000000..c250229dd9
--- /dev/null
+++ b/spec/build/bsps/optflushkerncharout.yml
@@ -0,0 +1,20 @@
+SPDX-License-Identifier: CC-BY-SA-4.0 OR BSD-2-Clause
+actions:
+- get-integer: null
+- define: null
+build-type: option
+copyrights:
+- Copyright (C) 2024 embedded brains GmbH & Co. KG
+default:
+- enabled-by: bsps/arm/xilinx-zynq
+  value: 1
+- enabled-by: true
+  value: 0
+description: |
+  If defined to a non-zero value, flush the kernel I/O output character device
+  provided by the BSP when the application exits.
+enabled-by: true
+format: '{}'
+links: []
+name: BSP_FLUSH_KERNEL_CHAR_OUTPUT
+type: build
-- 
2.35.3