logohack exit on escape

[bootcensus] / src / startup.s

diff --git a/src/startup.s b/src/startup.s
index 42e4b21..0a36b67 100644 (file)
--- a/src/startup.s
+++ b/src/startup.s
@@ -15,19 +15,37 @@
 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
        .code32
-       .section .startup
+       .section .startup,"ax"
 
        .extern _bss_start
        .extern _bss_end
+       .extern pcboot_main
+       .extern wait_vsync
+       .extern kb_getkey
 
+       # move the stack to the top of the conventional memory
+       movl $0x80000, %esp
+
+       # zero the BSS section
        xor %eax, %eax
-       mov _bss_start, %edi
-       mov _bss_size, %ecx
+       mov $_bss_start, %edi
+       mov $_bss_size, %ecx
+       cmp $0, %ecx
+       jz skip_bss_zero
        shr $4, %ecx
        rep stosl
+skip_bss_zero:
 
+       call pcboot_main
+       # pcboot_main never returns
+0:     cli
+       hlt
+       jmp 0b
 
+       .global logohack
 logohack:
+       pusha
+
        # copy palette
        mov $logo_pal, %esi
        xor %cl, %cl
@@ -117,22 +135,22 @@ xloop:
 
        incl frameno
 
-       # wait vsync
-       mov $0x3da, %dx
-0:     in %dx, %al
-       and $8, %al
-       jnz 0b
-0:     in %dx, %al
-       and $8, %al
-       jz 0b
+       call wait_vsync
+
+       # check for escape keypress
+       call kb_getkey
+       cmp $27, %eax
+       jz 0f
+
        jmp frameloop
 
+0:     popa
+       ret
+
 xval: .long 0
 yval: .long 0
 frameno: .long 0
 
-numbuf: .space 16
-
 logo_pal:
        .incbin "logo.pal"