1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright (C) 2001 Mike Corrigan & Dave Engebretsen, IBM Corporation
4  * Rewrite, cleanup:
5  * Copyright (C) 2004 Olof Johansson <olof@lixom.net>, IBM Corporation
6  */
7 
8 #ifndef _ASM_IOMMU_H
9 #define _ASM_IOMMU_H
10 #ifdef __KERNEL__
11 
12 #include <linux/compiler.h>
13 #include <linux/spinlock.h>
14 #include <linux/device.h>
15 #include <linux/dma-map-ops.h>
16 #include <linux/bitops.h>
17 #include <asm/machdep.h>
18 #include <asm/types.h>
19 #include <asm/pci-bridge.h>
20 #include <asm/asm-const.h>
21 
22 #define IOMMU_PAGE_SHIFT_4K      12
23 #define IOMMU_PAGE_SIZE_4K       (ASM_CONST(1) << IOMMU_PAGE_SHIFT_4K)
24 #define IOMMU_PAGE_MASK_4K       (~((1 << IOMMU_PAGE_SHIFT_4K) - 1))
25 #define IOMMU_PAGE_ALIGN_4K(addr) ALIGN(addr, IOMMU_PAGE_SIZE_4K)
26 
27 #define IOMMU_PAGE_SIZE(tblptr) (ASM_CONST(1) << (tblptr)->it_page_shift)
28 #define IOMMU_PAGE_MASK(tblptr) (~((1 << (tblptr)->it_page_shift) - 1))
29 #define IOMMU_PAGE_ALIGN(addr, tblptr) ALIGN(addr, IOMMU_PAGE_SIZE(tblptr))
30 
31 /* Boot time flags */
32 extern int iommu_is_off;
33 extern int iommu_force_on;
34 
35 struct iommu_table_ops {
36 	/*
37 	 * When called with direction==DMA_NONE, it is equal to clear().
38 	 * uaddr is a linear map address.
39 	 */
40 	int (*set)(struct iommu_table *tbl,
41 			long index, long npages,
42 			unsigned long uaddr,
43 			enum dma_data_direction direction,
44 			unsigned long attrs);
45 #ifdef CONFIG_IOMMU_API
46 	/*
47 	 * Exchanges existing TCE with new TCE plus direction bits;
48 	 * returns old TCE and DMA direction mask.
49 	 * @tce is a physical address.
50 	 */
51 	int (*xchg_no_kill)(struct iommu_table *tbl,
52 			long index,
53 			unsigned long *hpa,
54 			enum dma_data_direction *direction);
55 
56 	void (*tce_kill)(struct iommu_table *tbl,
57 			unsigned long index,
58 			unsigned long pages);
59 
60 	__be64 *(*useraddrptr)(struct iommu_table *tbl, long index, bool alloc);
61 #endif
62 	void (*clear)(struct iommu_table *tbl,
63 			long index, long npages);
64 	/* get() returns a physical address */
65 	unsigned long (*get)(struct iommu_table *tbl, long index);
66 	void (*flush)(struct iommu_table *tbl);
67 	void (*free)(struct iommu_table *tbl);
68 };
69 
70 /* These are used by VIO */
71 extern struct iommu_table_ops iommu_table_lpar_multi_ops;
72 extern struct iommu_table_ops iommu_table_pseries_ops;
73 
74 /*
75  * IOMAP_MAX_ORDER defines the largest contiguous block
76  * of dma space we can get.  IOMAP_MAX_ORDER = 13
77  * allows up to 2**12 pages (4096 * 4096) = 16 MB
78  */
79 #define IOMAP_MAX_ORDER		13
80 
81 #define IOMMU_POOL_HASHBITS	2
82 #define IOMMU_NR_POOLS		(1 << IOMMU_POOL_HASHBITS)
83 
84 struct iommu_pool {
85 	unsigned long start;
86 	unsigned long end;
87 	unsigned long hint;
88 	spinlock_t lock;
89 } ____cacheline_aligned_in_smp;
90 
91 struct iommu_table {
92 	unsigned long  it_busno;     /* Bus number this table belongs to */
93 	unsigned long  it_size;      /* Size of iommu table in entries */
94 	unsigned long  it_indirect_levels;
95 	unsigned long  it_level_size;
96 	unsigned long  it_allocated_size;
97 	unsigned long  it_offset;    /* Offset into global table */
98 	unsigned long  it_base;      /* mapped address of tce table */
99 	unsigned long  it_index;     /* which iommu table this is */
100 	unsigned long  it_type;      /* type: PCI or Virtual Bus */
101 	unsigned long  it_blocksize; /* Entries in each block (cacheline) */
102 	unsigned long  poolsize;
103 	unsigned long  nr_pools;
104 	struct iommu_pool large_pool;
105 	struct iommu_pool pools[IOMMU_NR_POOLS];
106 	unsigned long *it_map;       /* A simple allocation bitmap for now */
107 	unsigned long  it_page_shift;/* table iommu page size */
108 	struct list_head it_group_list;/* List of iommu_table_group_link */
109 	__be64 *it_userspace; /* userspace view of the table */
110 	struct iommu_table_ops *it_ops;
111 	struct kref    it_kref;
112 	int it_nid;
113 	unsigned long it_reserved_start; /* Start of not-DMA-able (MMIO) area */
114 	unsigned long it_reserved_end;
115 };
116 
117 #define IOMMU_TABLE_USERSPACE_ENTRY_RO(tbl, entry) \
118 		((tbl)->it_ops->useraddrptr((tbl), (entry), false))
119 #define IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry) \
120 		((tbl)->it_ops->useraddrptr((tbl), (entry), true))
121 
122 /* Pure 2^n version of get_order */
123 static inline __attribute_const__
get_iommu_order(unsigned long size,struct iommu_table * tbl)124 int get_iommu_order(unsigned long size, struct iommu_table *tbl)
125 {
126 	return __ilog2((size - 1) >> tbl->it_page_shift) + 1;
127 }
128 
129 
130 struct scatterlist;
131 
132 #ifdef CONFIG_PPC64
133 
set_iommu_table_base(struct device * dev,struct iommu_table * base)134 static inline void set_iommu_table_base(struct device *dev,
135 					struct iommu_table *base)
136 {
137 	dev->archdata.iommu_table_base = base;
138 }
139 
get_iommu_table_base(struct device * dev)140 static inline void *get_iommu_table_base(struct device *dev)
141 {
142 	return dev->archdata.iommu_table_base;
143 }
144 
145 extern int dma_iommu_dma_supported(struct device *dev, u64 mask);
146 
147 extern struct iommu_table *iommu_tce_table_get(struct iommu_table *tbl);
148 extern int iommu_tce_table_put(struct iommu_table *tbl);
149 
150 /* Initializes an iommu_table based in values set in the passed-in
151  * structure
152  */
153 extern struct iommu_table *iommu_init_table(struct iommu_table *tbl,
154 		int nid, unsigned long res_start, unsigned long res_end);
155 bool iommu_table_in_use(struct iommu_table *tbl);
156 
157 #define IOMMU_TABLE_GROUP_MAX_TABLES	2
158 
159 struct iommu_table_group;
160 
161 struct iommu_table_group_ops {
162 	unsigned long (*get_table_size)(
163 			__u32 page_shift,
164 			__u64 window_size,
165 			__u32 levels);
166 	long (*create_table)(struct iommu_table_group *table_group,
167 			int num,
168 			__u32 page_shift,
169 			__u64 window_size,
170 			__u32 levels,
171 			struct iommu_table **ptbl);
172 	long (*set_window)(struct iommu_table_group *table_group,
173 			int num,
174 			struct iommu_table *tblnew);
175 	long (*unset_window)(struct iommu_table_group *table_group,
176 			int num);
177 	/* Switch ownership from platform code to external user (e.g. VFIO) */
178 	void (*take_ownership)(struct iommu_table_group *table_group);
179 	/* Switch ownership from external user (e.g. VFIO) back to core */
180 	void (*release_ownership)(struct iommu_table_group *table_group);
181 };
182 
183 struct iommu_table_group_link {
184 	struct list_head next;
185 	struct rcu_head rcu;
186 	struct iommu_table_group *table_group;
187 };
188 
189 struct iommu_table_group {
190 	/* IOMMU properties */
191 	__u32 tce32_start;
192 	__u32 tce32_size;
193 	__u64 pgsizes; /* Bitmap of supported page sizes */
194 	__u32 max_dynamic_windows_supported;
195 	__u32 max_levels;
196 
197 	struct iommu_group *group;
198 	struct iommu_table *tables[IOMMU_TABLE_GROUP_MAX_TABLES];
199 	struct iommu_table_group_ops *ops;
200 };
201 
202 #ifdef CONFIG_IOMMU_API
203 
204 extern void iommu_register_group(struct iommu_table_group *table_group,
205 				 int pci_domain_number, unsigned long pe_num);
206 extern int iommu_add_device(struct iommu_table_group *table_group,
207 		struct device *dev);
208 extern void iommu_del_device(struct device *dev);
209 extern long iommu_tce_xchg(struct mm_struct *mm, struct iommu_table *tbl,
210 		unsigned long entry, unsigned long *hpa,
211 		enum dma_data_direction *direction);
212 extern long iommu_tce_xchg_no_kill(struct mm_struct *mm,
213 		struct iommu_table *tbl,
214 		unsigned long entry, unsigned long *hpa,
215 		enum dma_data_direction *direction);
216 extern void iommu_tce_kill(struct iommu_table *tbl,
217 		unsigned long entry, unsigned long pages);
218 #else
iommu_register_group(struct iommu_table_group * table_group,int pci_domain_number,unsigned long pe_num)219 static inline void iommu_register_group(struct iommu_table_group *table_group,
220 					int pci_domain_number,
221 					unsigned long pe_num)
222 {
223 }
224 
iommu_add_device(struct iommu_table_group * table_group,struct device * dev)225 static inline int iommu_add_device(struct iommu_table_group *table_group,
226 		struct device *dev)
227 {
228 	return 0;
229 }
230 
iommu_del_device(struct device * dev)231 static inline void iommu_del_device(struct device *dev)
232 {
233 }
234 #endif /* !CONFIG_IOMMU_API */
235 
236 u64 dma_iommu_get_required_mask(struct device *dev);
237 #else
238 
get_iommu_table_base(struct device * dev)239 static inline void *get_iommu_table_base(struct device *dev)
240 {
241 	return NULL;
242 }
243 
dma_iommu_dma_supported(struct device * dev,u64 mask)244 static inline int dma_iommu_dma_supported(struct device *dev, u64 mask)
245 {
246 	return 0;
247 }
248 
249 #endif /* CONFIG_PPC64 */
250 
251 extern int ppc_iommu_map_sg(struct device *dev, struct iommu_table *tbl,
252 			    struct scatterlist *sglist, int nelems,
253 			    unsigned long mask,
254 			    enum dma_data_direction direction,
255 			    unsigned long attrs);
256 extern void ppc_iommu_unmap_sg(struct iommu_table *tbl,
257 			       struct scatterlist *sglist,
258 			       int nelems,
259 			       enum dma_data_direction direction,
260 			       unsigned long attrs);
261 
262 extern void *iommu_alloc_coherent(struct device *dev, struct iommu_table *tbl,
263 				  size_t size, dma_addr_t *dma_handle,
264 				  unsigned long mask, gfp_t flag, int node);
265 extern void iommu_free_coherent(struct iommu_table *tbl, size_t size,
266 				void *vaddr, dma_addr_t dma_handle);
267 extern dma_addr_t iommu_map_page(struct device *dev, struct iommu_table *tbl,
268 				 struct page *page, unsigned long offset,
269 				 size_t size, unsigned long mask,
270 				 enum dma_data_direction direction,
271 				 unsigned long attrs);
272 extern void iommu_unmap_page(struct iommu_table *tbl, dma_addr_t dma_handle,
273 			     size_t size, enum dma_data_direction direction,
274 			     unsigned long attrs);
275 
276 void __init iommu_init_early_pSeries(void);
277 extern void iommu_init_early_dart(struct pci_controller_ops *controller_ops);
278 extern void iommu_init_early_pasemi(void);
279 
280 #if defined(CONFIG_PPC64) && defined(CONFIG_PM)
iommu_restore(void)281 static inline void iommu_restore(void)
282 {
283 	if (ppc_md.iommu_restore)
284 		ppc_md.iommu_restore();
285 }
286 #endif
287 
288 /* The API to support IOMMU operations for VFIO */
289 extern int iommu_tce_check_ioba(unsigned long page_shift,
290 		unsigned long offset, unsigned long size,
291 		unsigned long ioba, unsigned long npages);
292 extern int iommu_tce_check_gpa(unsigned long page_shift,
293 		unsigned long gpa);
294 
295 #define iommu_tce_clear_param_check(tbl, ioba, tce_value, npages) \
296 		(iommu_tce_check_ioba((tbl)->it_page_shift,       \
297 				(tbl)->it_offset, (tbl)->it_size, \
298 				(ioba), (npages)) || (tce_value))
299 #define iommu_tce_put_param_check(tbl, ioba, gpa)                 \
300 		(iommu_tce_check_ioba((tbl)->it_page_shift,       \
301 				(tbl)->it_offset, (tbl)->it_size, \
302 				(ioba), 1) ||                     \
303 		iommu_tce_check_gpa((tbl)->it_page_shift, (gpa)))
304 
305 extern void iommu_flush_tce(struct iommu_table *tbl);
306 extern int iommu_take_ownership(struct iommu_table *tbl);
307 extern void iommu_release_ownership(struct iommu_table *tbl);
308 
309 extern enum dma_data_direction iommu_tce_direction(unsigned long tce);
310 extern unsigned long iommu_direction_to_tce_perm(enum dma_data_direction dir);
311 
312 #ifdef CONFIG_PPC_CELL_NATIVE
313 extern bool iommu_fixed_is_weak;
314 #else
315 #define iommu_fixed_is_weak false
316 #endif
317 
318 extern const struct dma_map_ops dma_iommu_ops;
319 
320 #endif /* __KERNEL__ */
321 #endif /* _ASM_IOMMU_H */
322