From a6bbbe9634e770f30324be5f05f144989a9be48d Mon Sep 17 00:00:00 2001
From: Arjob Mukherjee <arjobmukherjee@gmail.com>
Date: Sun, 17 Nov 2024 04:20:27 +0530
Subject: [PATCH] Now kdisp*() only defined for non-graphical, debug builds

We were writing to VGA text buffer even for graphics builds, which makes
no sense. With this change VGA Text related functions are only included
for non-graphical, debug builds.

Note:
* For Graphical, debug builds though kearly_printf will be defined,
  it will not print anywhere. It will later print to VirtualScreen, but
  its yet implemented.
---
 include/kernel.h              |  2 ++
 src/kernel/kpanic.c           |  2 ++
 src/kernel/printk.c           | 19 ++++++++++++-------
 src/kernel/x86/CMakeLists.txt |  5 ++++-
 src/kernel/x86/kernel.c       |  7 ++++++-
 5 files changed, 26 insertions(+), 9 deletions(-)

diff --git a/include/kernel.h b/include/kernel.h
index b84ab83..d6c65d4 100644
--- a/include/kernel.h
+++ b/include/kernel.h
@@ -16,7 +16,9 @@
 typedef struct KernelStateInfo {
     enum {
         KERNEL_PHASE_STATE_BOOT_COMPLETE = 0,
+#if defined(DEBUG) && !defined(GRAPHICS_MODE_ENABLED)
         KERNEL_PHASE_STATE_TEXTDISP_READY,
+#endif
         KERNEL_PHASE_STATE_PMM_READY,
         KERNEL_PHASE_STATE_SALLOC_READY,
         KERNEL_PHASE_STATE_VMM_READY,
diff --git a/src/kernel/kpanic.c b/src/kernel/kpanic.c
index df0b7b3..a505957 100644
--- a/src/kernel/kpanic.c
+++ b/src/kernel/kpanic.c
@@ -64,7 +64,9 @@ void kpanic_ndu (UINT line, const CHAR* file, const CHAR* fmt, ...)
 
 #ifdef DEBUG
     kdebug_printf ("%s", buffer);
+    #ifndef GRAPHICS_MODE_ENABLED
     kearly_printf (buffer);
+    #endif
 #endif
 
     k_halt();
diff --git a/src/kernel/printk.c b/src/kernel/printk.c
index 33e847d..a0ce355 100644
--- a/src/kernel/printk.c
+++ b/src/kernel/printk.c
@@ -29,13 +29,15 @@ static IntTypes s_readtype (const CHAR **fmt, CHAR *c);
 static U64 s_readint (IntTypes inttype, va_list *l);
 
 #if defined(DEBUG)
-static void s_prnstr (const CHAR *str);
+    #if !defined(GRAPHICS_MODE_ENABLED)
+static void s_prnstr (const CHAR* str);
 
-static void s_prnstr (const CHAR *str)
+static void s_prnstr (const CHAR* str)
 {
-    for (;*str;str++)
+    for (; *str; str++)
         kdisp_putc (*str);
 }
+    #endif
 
 /***************************************************************************************************
  * Prints on screen the arguments in the format specified.
@@ -50,8 +52,6 @@ static void s_prnstr (const CHAR *str)
  **************************************************************************************************/
 INT kearly_printf (const CHAR *fmt, ...)
 {
-    KERNEL_PHASE_VALIDATE(KERNEL_PHASE_STATE_TEXTDISP_READY);
-
     va_list l;
     va_start (l, fmt);
 
@@ -60,10 +60,15 @@ INT kearly_printf (const CHAR *fmt, ...)
 
     va_end (l);
 
-    s_prnstr (buffer);    
+    #if !defined(GRAPHICS_MODE_ENABLED)
+    KERNEL_PHASE_VALIDATE(KERNEL_PHASE_STATE_TEXTDISP_READY);
+    s_prnstr (buffer);
+    #else
+    // TODO: VirtualScreen not yet implemented.
+    #endif
     return len;
 }
-#endif
+#endif // DEBUG
 
 /***************************************************************************************************
  * Writes to a string pointer the arguments in the format specified.
diff --git a/src/kernel/x86/CMakeLists.txt b/src/kernel/x86/CMakeLists.txt
index 5a2ab2f..7185f69 100644
--- a/src/kernel/x86/CMakeLists.txt
+++ b/src/kernel/x86/CMakeLists.txt
@@ -9,9 +9,12 @@ set(KERNEL_X86_SOURCES
     ${CMAKE_CURRENT_SOURCE_DIR}/process.c
     ${CMAKE_CURRENT_SOURCE_DIR}/syscalls.c
     ${CMAKE_CURRENT_SOURCE_DIR}/tss.c
-    ${CMAKE_CURRENT_SOURCE_DIR}/vgadisp.c
     )
 
+    if (MOS_BUILD_MODE STREQUAL "DEBUG" AND NOT MOS_GRAPHICS_ENABLED)
+        LIST(APPEND KERNEL_X86_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/vgatext.c)
+    endif()
+
 compile_lib(
     NAME kernel_X86
     SOURCES ${KERNEL_X86_SOURCES}
diff --git a/src/kernel/x86/kernel.c b/src/kernel/x86/kernel.c
index ce268fe..c4eb370 100644
--- a/src/kernel/x86/kernel.c
+++ b/src/kernel/x86/kernel.c
@@ -62,8 +62,11 @@ void kernel_main ()
     FUNC_ENTRY();
 
     KERNEL_PHASE_SET(KERNEL_PHASE_STATE_BOOT_COMPLETE);
+
+#if defined(DEBUG) && !defined(GRAPHICS_MODE_ENABLED)
     // Initialize Text display
-    kdisp_init ();
+    kdisp_init();
+#endif
 
     // Initilaize Physical Memory Manger
     kpmm_init ();
@@ -148,9 +151,11 @@ void kernel_main ()
     KERNEL_PHASE_SET(KERNEL_PHASE_STATE_KERNEL_READY);
     kearly_printf ("\r[OK]");
 
+#if defined(DEBUG) && !defined(GRAPHICS_MODE_ENABLED)
     kdisp_ioctl (DISP_SETATTR,k_dispAttr (BLACK,GREEN,0));
     kearly_println ("Kernel initialization finished..");
     kdisp_ioctl (DISP_SETATTR,k_dispAttr (BLACK,LIGHT_GRAY,0));
+#endif
 
     //---------------
     int cpuflags_present = 0;