drivers/vga: map and register VGA console only when supported

Signed-off-by: Pawel Wieczorkiewicz <[email protected]>
KernelTestFramework · Aug 30, 2021 · 3868874 · 3868874
1 parent 3100556
commit 3868874
Showing 1 changed file with 12 additions and 4 deletions.
diff --git a/common/setup.c b/common/setup.c
@@ -157,9 +157,7 @@ static void __text_init init_console(void) {
     get_com_ports();
 
     uart_init(com_ports[0], DEFAULT_BAUD_SPEED);
-
     register_console_callback(serial_console_write);
-    register_console_callback(vga_console_write);
 
     printk("COM1: %x, COM2: %x\n", com_ports[0], com_ports[1]);
 }
@@ -183,7 +181,7 @@ void zap_boot_mappings(void) {
     }
 }
 
-static void map_bios_area(void) {
+static void __text_init map_bios_area(void) {
     vmap_4k(paddr_to_virt(BDA_ADDR_START), paddr_to_mfn(BDA_ADDR_START), L1_PROT_RO);
     kmap_4k(paddr_to_mfn(BDA_ADDR_START), L1_PROT_RO);
 
@@ -196,6 +194,15 @@ static void map_bios_area(void) {
         kmap_4k(bios_mfn, L1_PROT_RO);
 }
 
+static void __text_init init_vga_console(void) {
+    if (!boot_flags.vga)
+        return;
+
+    printk("Enabling VGA support\n");
+    map_vga_area();
+    register_console_callback(vga_console_write);
+}
+
 void __noreturn __text_init kernel_start(uint32_t multiboot_magic,
                                          multiboot_info_t *mbi) {
     /* Zero-out BSS sections */
@@ -239,7 +246,6 @@ void __noreturn __text_init kernel_start(uint32_t multiboot_magic,
 
     map_multiboot_areas();
     map_bios_area();
-    map_vga_area();
 
     write_cr3(cr3.paddr);
     boot_flags.virt = true;
@@ -260,6 +266,8 @@ void __noreturn __text_init kernel_start(uint32_t multiboot_magic,
         BUG();
     }
 
+    init_vga_console();
+
     init_apic(get_bsp_cpu_id(), APIC_MODE_XAPIC);
 
     init_tasks();