From: Alan Cox <alan@linux.intel.com>
Date: Sun, 1 Nov 2015 21:02:56 +0000 (+0000)
Subject: ubee: missed this in the old commits
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=9ca7344353302e1ddfc89eb0592bf9557b72dc31;p=FUZIX.git

ubee: missed this in the old commits

Not yet anything useful here... still need to write the disk manipulation
toolchain
---

diff --git a/Kernel/platform-ubee/crt0.s b/Kernel/platform-ubee/crt0.s
new file mode 100644
index 00000000..78fe134b
--- /dev/null
+++ b/Kernel/platform-ubee/crt0.s
@@ -0,0 +1,68 @@
+	        ; Ordering of segments for the linker.
+	        ; WRS: Note we list all our segments here, even though
+	        ; we don't use them all, because their ordering is set
+	        ; when they are first seen.	
+	        .area _CODE
+	        .area _CODE2
+		.area _VIDEO
+	        .area _CONST
+	        .area _INITIALIZED
+	        .area _DATA
+	        .area _BSEG
+	        .area _BSS
+	        .area _HEAP
+	        ; note that areas below here may be overwritten by the heap at runtime, so
+	        ; put initialisation stuff in here
+	        .area _INITIALIZER
+	        .area _GSINIT
+	        .area _GSFINAL
+	        .area _COMMONMEM
+		.area _DISCARD
+
+        	; imported symbols
+        	.globl _fuzix_main
+	        .globl init_early
+	        .globl init_hardware
+	        .globl s__DATA
+	        .globl l__DATA
+	        .globl s__DISCARD
+	        .globl l__DISCARD
+	        .globl s__COMMONMEM
+	        .globl l__COMMONMEM
+		.globl s__INITIALIZER
+	        .globl kstack_top
+
+	        ; startup code
+	        .area _CODE
+
+;
+;	Once the loader completes it jumps here
+;
+start:
+		ld sp, #kstack_top
+		; move the common memory where it belongs    
+		ld hl, #s__DATA
+		ld de, #s__COMMONMEM
+		ld bc, #l__COMMONMEM
+		ldir
+		; then the discard
+		ld de, #s__DISCARD
+		ld bc, #l__DISCARD
+		ldir
+		; then zero the data area
+		ld hl, #s__DATA
+		ld de, #s__DATA + 1
+		ld bc, #l__DATA - 1
+		ld (hl), #0
+		ldir
+
+;	TODO: Move the common into the other bank, pain as we may well have
+;	code in low bank and __COMMON packed in high. Needs to be in
+;	.COMMONMEM and map the other page low
+;
+		call init_early
+		call init_hardware
+		call _fuzix_main
+		di
+stop:		halt
+		jr stop