tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
1/*
2 * Copyright 2010 Tilera Corporation. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation, version 2.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11 * NON INFRINGEMENT. See the GNU General Public License for
12 * more details.
13 */
14
15#ifndef _ASM_TILE_PAGE_H
16#define _ASM_TILE_PAGE_H
17
18#include <linux/const.h>
19#include <hv/pagesize.h>
20
21/* PAGE_SHIFT and HPAGE_SHIFT determine the page sizes. */
22#define PAGE_SHIFT HV_LOG2_PAGE_SIZE_SMALL
23#define HPAGE_SHIFT HV_LOG2_PAGE_SIZE_LARGE
24
25#define PAGE_SIZE (_AC(1, UL) << PAGE_SHIFT)
26#define HPAGE_SIZE (_AC(1, UL) << HPAGE_SHIFT)
27
28#define PAGE_MASK (~(PAGE_SIZE - 1))
29#define HPAGE_MASK (~(HPAGE_SIZE - 1))
30
31#ifdef __KERNEL__
32
33/*
34 * If the Kconfig doesn't specify, set a maximum zone order that
35 * is enough so that we can create huge pages from small pages given
36 * the respective sizes of the two page types. See <linux/mmzone.h>.
37 */
38#ifndef CONFIG_FORCE_MAX_ZONEORDER
39#define CONFIG_FORCE_MAX_ZONEORDER (HPAGE_SHIFT - PAGE_SHIFT + 1)
40#endif
41
42#include <hv/hypervisor.h>
43#include <arch/chip.h>
44
45#ifndef __ASSEMBLY__
46
47#include <linux/types.h>
48#include <linux/string.h>
49
50struct page;
51
52static inline void clear_page(void *page)
53{
54 memset(page, 0, PAGE_SIZE);
55}
56
57static inline void copy_page(void *to, void *from)
58{
59 memcpy(to, from, PAGE_SIZE);
60}
61
62static inline void clear_user_page(void *page, unsigned long vaddr,
63 struct page *pg)
64{
65 clear_page(page);
66}
67
68static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
69 struct page *topage)
70{
71 copy_page(to, from);
72}
73
74/*
75 * Hypervisor page tables are made of the same basic structure.
76 */
77
78typedef HV_PTE pte_t;
79typedef HV_PTE pgd_t;
80typedef HV_PTE pgprot_t;
81
82/*
83 * User L2 page tables are managed as one L2 page table per page,
84 * because we use the page allocator for them. This keeps the allocation
85 * simple and makes it potentially useful to implement HIGHPTE at some point.
86 * However, it's also inefficient, since L2 page tables are much smaller
87 * than pages (currently 2KB vs 64KB). So we should revisit this.
88 */
89typedef struct page *pgtable_t;
90
91/* Must be a macro since it is used to create constants. */
92#define __pgprot(val) hv_pte(val)
93
94static inline u64 pgprot_val(pgprot_t pgprot)
95{
96 return hv_pte_val(pgprot);
97}
98
99static inline u64 pte_val(pte_t pte)
100{
101 return hv_pte_val(pte);
102}
103
104static inline u64 pgd_val(pgd_t pgd)
105{
106 return hv_pte_val(pgd);
107}
108
109#ifdef __tilegx__
110
111typedef HV_PTE pmd_t;
112
113static inline u64 pmd_val(pmd_t pmd)
114{
115 return hv_pte_val(pmd);
116}
117
118#endif
119
120static inline __attribute_const__ int get_order(unsigned long size)
121{
122 return BITS_PER_LONG - __builtin_clzl((size - 1) >> PAGE_SHIFT);
123}
124
125#endif /* !__ASSEMBLY__ */
126
127#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)
128
129#define HUGE_MAX_HSTATE 2
130
131#ifdef CONFIG_HUGETLB_PAGE
132#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
133#endif
134
135/* Each memory controller has PAs distinct in their high bits. */
136#define NR_PA_HIGHBIT_SHIFT (CHIP_PA_WIDTH() - CHIP_LOG_NUM_MSHIMS())
137#define NR_PA_HIGHBIT_VALUES (1 << CHIP_LOG_NUM_MSHIMS())
138#define __pa_to_highbits(pa) ((phys_addr_t)(pa) >> NR_PA_HIGHBIT_SHIFT)
139#define __pfn_to_highbits(pfn) ((pfn) >> (NR_PA_HIGHBIT_SHIFT - PAGE_SHIFT))
140
141#ifdef __tilegx__
142
143/*
144 * We reserve the lower half of memory for user-space programs, and the
145 * upper half for system code. We re-map all of physical memory in the
146 * upper half, which takes a quarter of our VA space. Then we have
147 * the vmalloc regions. The supervisor code lives at 0xfffffff700000000,
148 * with the hypervisor above that.
149 *
150 * Loadable kernel modules are placed immediately after the static
151 * supervisor code, with each being allocated a 256MB region of
152 * address space, so we don't have to worry about the range of "jal"
153 * and other branch instructions.
154 *
155 * For now we keep life simple and just allocate one pmd (4GB) for vmalloc.
156 * Similarly, for now we don't play any struct page mapping games.
157 */
158
159#if CHIP_PA_WIDTH() + 2 > CHIP_VA_WIDTH()
160# error Too much PA to map with the VA available!
161#endif
162#define HALF_VA_SPACE (_AC(1, UL) << (CHIP_VA_WIDTH() - 1))
163
164#define MEM_LOW_END (HALF_VA_SPACE - 1) /* low half */
165#define MEM_HIGH_START (-HALF_VA_SPACE) /* high half */
166#define PAGE_OFFSET MEM_HIGH_START
167#define _VMALLOC_START _AC(0xfffffff500000000, UL) /* 4 GB */
168#define HUGE_VMAP_BASE _AC(0xfffffff600000000, UL) /* 4 GB */
169#define MEM_SV_START _AC(0xfffffff700000000, UL) /* 256 MB */
170#define MEM_SV_INTRPT MEM_SV_START
171#define MEM_MODULE_START _AC(0xfffffff710000000, UL) /* 256 MB */
172#define MEM_MODULE_END (MEM_MODULE_START + (256*1024*1024))
173#define MEM_HV_START _AC(0xfffffff800000000, UL) /* 32 GB */
174
175/* Highest DTLB address we will use */
176#define KERNEL_HIGH_VADDR MEM_SV_START
177
178/* Since we don't currently provide any fixmaps, we use an impossible VA. */
179#define FIXADDR_TOP MEM_HV_START
180
181#else /* !__tilegx__ */
182
183/*
184 * A PAGE_OFFSET of 0xC0000000 means that the kernel has
185 * a virtual address space of one gigabyte, which limits the
186 * amount of physical memory you can use to about 768MB.
187 * If you want more physical memory than this then see the CONFIG_HIGHMEM
188 * option in the kernel configuration.
189 *
190 * The top 16MB chunk in the table below is unavailable to Linux. Since
191 * the kernel interrupt vectors must live at ether 0xfe000000 or 0xfd000000
192 * (depending on whether the kernel is at PL2 or Pl1), we map all of the
193 * bottom of RAM at this address with a huge page table entry to minimize
194 * its ITLB footprint (as well as at PAGE_OFFSET). The last architected
195 * requirement is that user interrupt vectors live at 0xfc000000, so we
196 * make that range of memory available to user processes. The remaining
197 * regions are sized as shown; the first four addresses use the PL 1
198 * values, and after that, we show "typical" values, since the actual
199 * addresses depend on kernel #defines.
200 *
201 * MEM_HV_INTRPT 0xfe000000
202 * MEM_SV_INTRPT (kernel code) 0xfd000000
203 * MEM_USER_INTRPT (user vector) 0xfc000000
204 * FIX_KMAP_xxx 0xf8000000 (via NR_CPUS * KM_TYPE_NR)
205 * PKMAP_BASE 0xf7000000 (via LAST_PKMAP)
206 * HUGE_VMAP 0xf3000000 (via CONFIG_NR_HUGE_VMAPS)
207 * VMALLOC_START 0xf0000000 (via __VMALLOC_RESERVE)
208 * mapped LOWMEM 0xc0000000
209 */
210
211#define MEM_USER_INTRPT _AC(0xfc000000, UL)
212#if CONFIG_KERNEL_PL == 1
213#define MEM_SV_INTRPT _AC(0xfd000000, UL)
214#define MEM_HV_INTRPT _AC(0xfe000000, UL)
215#else
216#define MEM_GUEST_INTRPT _AC(0xfd000000, UL)
217#define MEM_SV_INTRPT _AC(0xfe000000, UL)
218#define MEM_HV_INTRPT _AC(0xff000000, UL)
219#endif
220
221#define INTRPT_SIZE 0x4000
222
223/* Tolerate page size larger than the architecture interrupt region size. */
224#if PAGE_SIZE > INTRPT_SIZE
225#undef INTRPT_SIZE
226#define INTRPT_SIZE PAGE_SIZE
227#endif
228
229#define KERNEL_HIGH_VADDR MEM_USER_INTRPT
230#define FIXADDR_TOP (KERNEL_HIGH_VADDR - PAGE_SIZE)
231
232#define PAGE_OFFSET _AC(CONFIG_PAGE_OFFSET, UL)
233
234/* On 32-bit architectures we mix kernel modules in with other vmaps. */
235#define MEM_MODULE_START VMALLOC_START
236#define MEM_MODULE_END VMALLOC_END
237
238#endif /* __tilegx__ */
239
240#ifndef __ASSEMBLY__
241
242#ifdef CONFIG_HIGHMEM
243
244/* Map kernel virtual addresses to page frames, in HPAGE_SIZE chunks. */
245extern unsigned long pbase_map[];
246extern void *vbase_map[];
247
248static inline unsigned long kaddr_to_pfn(const volatile void *_kaddr)
249{
250 unsigned long kaddr = (unsigned long)_kaddr;
251 return pbase_map[kaddr >> HPAGE_SHIFT] +
252 ((kaddr & (HPAGE_SIZE - 1)) >> PAGE_SHIFT);
253}
254
255static inline void *pfn_to_kaddr(unsigned long pfn)
256{
257 return vbase_map[__pfn_to_highbits(pfn)] + (pfn << PAGE_SHIFT);
258}
259
260static inline phys_addr_t virt_to_phys(const volatile void *kaddr)
261{
262 unsigned long pfn = kaddr_to_pfn(kaddr);
263 return ((phys_addr_t)pfn << PAGE_SHIFT) +
264 ((unsigned long)kaddr & (PAGE_SIZE-1));
265}
266
267static inline void *phys_to_virt(phys_addr_t paddr)
268{
269 return pfn_to_kaddr(paddr >> PAGE_SHIFT) + (paddr & (PAGE_SIZE-1));
270}
271
272/* With HIGHMEM, we pack PAGE_OFFSET through high_memory with all valid VAs. */
273static inline int virt_addr_valid(const volatile void *kaddr)
274{
275 extern void *high_memory; /* copied from <linux/mm.h> */
276 return ((unsigned long)kaddr >= PAGE_OFFSET && kaddr < high_memory);
277}
278
279#else /* !CONFIG_HIGHMEM */
280
281static inline unsigned long kaddr_to_pfn(const volatile void *kaddr)
282{
283 return ((unsigned long)kaddr - PAGE_OFFSET) >> PAGE_SHIFT;
284}
285
286static inline void *pfn_to_kaddr(unsigned long pfn)
287{
288 return (void *)((pfn << PAGE_SHIFT) + PAGE_OFFSET);
289}
290
291static inline phys_addr_t virt_to_phys(const volatile void *kaddr)
292{
293 return (phys_addr_t)((unsigned long)kaddr - PAGE_OFFSET);
294}
295
296static inline void *phys_to_virt(phys_addr_t paddr)
297{
298 return (void *)((unsigned long)paddr + PAGE_OFFSET);
299}
300
301/* Check that the given address is within some mapped range of PAs. */
302#define virt_addr_valid(kaddr) pfn_valid(kaddr_to_pfn(kaddr))
303
304#endif /* !CONFIG_HIGHMEM */
305
306/* All callers are not consistent in how they call these functions. */
307#define __pa(kaddr) virt_to_phys((void *)(unsigned long)(kaddr))
308#define __va(paddr) phys_to_virt((phys_addr_t)(paddr))
309
310extern int devmem_is_allowed(unsigned long pagenr);
311
312#ifdef CONFIG_FLATMEM
313static inline int pfn_valid(unsigned long pfn)
314{
315 return pfn < max_mapnr;
316}
317#endif
318
319/* Provide as macros since these require some other headers included. */
320#define page_to_pa(page) ((phys_addr_t)(page_to_pfn(page)) << PAGE_SHIFT)
321#define virt_to_page(kaddr) pfn_to_page(kaddr_to_pfn(kaddr))
322#define page_to_virt(page) pfn_to_kaddr(page_to_pfn(page))
323
324struct mm_struct;
325extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
326
327#endif /* !__ASSEMBLY__ */
328
329#define VM_DATA_DEFAULT_FLAGS \
330 (VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
331
332#include <asm-generic/memory_model.h>
333
334#endif /* __KERNEL__ */
335
336#endif /* _ASM_TILE_PAGE_H */