1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * OpenRISC Linux 4 * 5 * Linux architectural port borrowing liberally from similar works of 6 * others. All original copyrights apply as per the original source 7 * declaration. 8 * 9 * OpenRISC implementation: 10 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com> 11 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se> 12 * et al. 13 */ 14 15 #ifndef __ASM_OPENRISC_FIXMAP_H 16 #define __ASM_OPENRISC_FIXMAP_H 17 18 /* Why exactly do we need 2 empty pages between the top of the fixed 19 * addresses and the top of virtual memory? Something is using that 20 * memory space but not sure what right now... If you find it, leave 21 * a comment here. 22 */ 23 #define FIXADDR_TOP ((unsigned long) (-2*PAGE_SIZE)) 24 25 #include <linux/kernel.h> 26 #include <linux/bug.h> 27 #include <asm/page.h> 28 29 /* 30 * On OpenRISC we use these special fixed_addresses for doing ioremap 31 * early in the boot process before memory initialization is complete. 32 * This is used, in particular, by the early serial console code. 33 * 34 * It's not really 'fixmap', per se, but fits loosely into the same 35 * paradigm. 36 */ 37 enum fixed_addresses { 38 /* 39 * FIX_IOREMAP entries are useful for mapping physical address 40 * space before ioremap() is useable, e.g. really early in boot 41 * before kmalloc() is working. 42 */ 43 #define FIX_N_IOREMAPS 32 44 FIX_IOREMAP_BEGIN, 45 FIX_IOREMAP_END = FIX_IOREMAP_BEGIN + FIX_N_IOREMAPS - 1, 46 __end_of_fixed_addresses 47 }; 48 49 #define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) 50 /* FIXADDR_BOTTOM might be a better name here... */ 51 #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) 52 53 #include <asm-generic/fixmap.h> 54 55 #endif 56