# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1462395898 -7200
# Node ID eda8506725e5a6b20792eccd2fdd26c7400a8703
# Parent  010e441bc874e01d9c4e32b55b6cbd0e313e4e45
Made an inline function for address space conversion.
Defined the end of the memory in the linker script for consistency.

diff -r 010e441bc874 -r eda8506725e5 stage2/Makefile
--- a/stage2/Makefile	Wed May 04 22:57:56 2016 +0200
+++ b/stage2/Makefile	Wed May 04 23:04:58 2016 +0200
@@ -61,9 +61,10 @@
 DEFS = $(BOARD_DEFS)
 
 # Ordering of objects is important and cannot be left to replacement rules.
+# In particular the head2 file must appear first.
 
-SRC = head2.S entry.S handlers.S stage2.c cpu.c cpu_op.S lcd.c jzlcd.c board.c irq.c tasks.c example.c $(BOARD_SRC)
-OBJ = head2.o entry.o handlers.o stage2.o cpu.o cpu_op.o lcd.o jzlcd.o board.o irq.o tasks.o example.o $(BOARD_OBJ)
+SRC = head2.S entry.S handlers.S stage2.c cpu.c cpu_op.S lcd.c jzlcd.c board.c irq.c paging.c tasks.c example.c $(BOARD_SRC)
+OBJ = head2.o entry.o handlers.o stage2.o cpu.o cpu_op.o lcd.o jzlcd.o board.o irq.o paging.o tasks.o example.o $(BOARD_OBJ)
 
 .PHONY:	all clean distclean
 
diff -r 010e441bc874 -r eda8506725e5 stage2/paging.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/stage2/paging.c	Wed May 04 23:04:58 2016 +0200
@@ -0,0 +1,25 @@
+/*
+ * Paging utilities.
+ *
+ * Copyright (C) 2016 Paul Boddie <paul@boddie.org.uk>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "paging.h"
+
+inline u32 user_address(u32 addr)
+{
+	return addr & USER_ADDRESS_MASK;
+}
diff -r 010e441bc874 -r eda8506725e5 stage2/paging.h
--- a/stage2/paging.h	Wed May 04 22:57:56 2016 +0200
+++ b/stage2/paging.h	Wed May 04 23:04:58 2016 +0200
@@ -4,4 +4,14 @@
 #define page_table_start	0x81400000
 #define page_table_task_size	0x00008000
 
+#define USER_ADDRESS_MASK	0x7fffffff
+
+#ifndef __ASSEMBLER__
+
+#include "xburst_types.h"
+
+u32 user_address(u32 addr);
+
+#endif /* __ASSEMBLER__ */
+
 #endif /* __PAGING_H__ */
diff -r 010e441bc874 -r eda8506725e5 stage2/stage2.ld
--- a/stage2/stage2.ld	Wed May 04 22:57:56 2016 +0200
+++ b/stage2/stage2.ld	Wed May 04 23:04:58 2016 +0200
@@ -36,5 +36,6 @@
 		. += _got_end - _got_start;
 	}
 	_got_copy_end = ABSOLUTE(.);
+	_memory_end = 0x82000000;
 }
 
diff -r 010e441bc874 -r eda8506725e5 stage2/tasks.c
--- a/stage2/tasks.c	Wed May 04 22:57:56 2016 +0200
+++ b/stage2/tasks.c	Wed May 04 23:04:58 2016 +0200
@@ -41,9 +41,9 @@
 
 extern u32 _got_start, _got_copy_start, _got_copy_end;
 
-/* A reference to the start of the payload. */
+/* A reference to the start of the payload and end of memory locations. */
 
-extern u32 _payload_start;
+extern u32 _payload_start, _memory_end;
 
 /* Task management functions. */
 
@@ -89,18 +89,18 @@
 
 	/* Map the global object table for the task. */
 
-	init_page_table(page_table_start, (u32) &_got_start & 0x7fffffff, (u32) &_got_copy_start & 0x7fffffff, pagesize, 0x1e, task);
+	init_page_table(page_table_start, user_address((u32) &_got_start), user_address((u32) &_got_copy_start), pagesize, 0x1e, task);
 
 	/* Map all shared pages for the task. */
 
 	for (address = (u32) &_payload_start; address < (u32) &_got_start; address += pagesize * 2)
 	{
-		init_page_table(page_table_start, address & 0x7fffffff, address & 0x7fffffff, pagesize, 0x1e, task);
+		init_page_table(page_table_start, user_address(address), user_address(address), pagesize, 0x1e, task);
 	}
 
-	for (address = (u32) &_got_copy_end + pagesize * 2; address < 0x82000000; address += pagesize * 2)
+	for (address = (u32) &_got_copy_end + pagesize * 2; address < (u32) &_memory_end; address += pagesize * 2)
 	{
-		init_page_table(page_table_start, address & 0x7fffffff, address & 0x7fffffff, pagesize, 0x1e, task);
+		init_page_table(page_table_start, user_address(address), user_address(address), pagesize, 0x1e, task);
 	}
 }