^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) /* SPDX-License-Identifier: GPL-2.0-or-later */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * OpenRISC Linux
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Linux architectural port borrowing liberally from similar works of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * others. All original copyrights apply as per the original source
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * declaration.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * OpenRISC implementation:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) * et al.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #ifndef __ASM_OPENRISC_FIXMAP_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #define __ASM_OPENRISC_FIXMAP_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) /* Why exactly do we need 2 empty pages between the top of the fixed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) * addresses and the top of virtual memory? Something is using that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) * memory space but not sure what right now... If you find it, leave
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) * a comment here.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #define FIXADDR_TOP ((unsigned long) (-2*PAGE_SIZE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) #include <linux/bug.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) #include <asm/page.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * On OpenRISC we use these special fixed_addresses for doing ioremap
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * early in the boot process before memory initialization is complete.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) * This is used, in particular, by the early serial console code.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) * It's not really 'fixmap', per se, but fits loosely into the same
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) * paradigm.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) enum fixed_addresses {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) * FIX_IOREMAP entries are useful for mapping physical address
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) * space before ioremap() is useable, e.g. really early in boot
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) * before kmalloc() is working.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) #define FIX_N_IOREMAPS 32
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) FIX_IOREMAP_BEGIN,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) FIX_IOREMAP_END = FIX_IOREMAP_BEGIN + FIX_N_IOREMAPS - 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) __end_of_fixed_addresses
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) #define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) /* FIXADDR_BOTTOM might be a better name here... */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) #define __fix_to_virt(x) (FIXADDR_TOP - ((x) << PAGE_SHIFT))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) #define __virt_to_fix(x) ((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) * 'index to address' translation. If anyone tries to use the idx
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) * directly without tranlation, we catch the bug with a NULL-deference
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) * kernel oops. Illegal ranges of incoming indices are caught too.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) static __always_inline unsigned long fix_to_virt(const unsigned int idx)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) * this branch gets completely eliminated after inlining,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) * except when someone tries to use fixaddr indices in an
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) * illegal way. (such as mixing up address types or using
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) * out-of-range indices).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) * If it doesn't get removed, the linker will complain
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) * loudly with a reasonably clear error message..
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) if (idx >= __end_of_fixed_addresses)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) BUG();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) return __fix_to_virt(idx);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) static inline unsigned long virt_to_fix(const unsigned long vaddr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) return __virt_to_fix(vaddr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) #endif
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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