1 /*
2 * omap iommu: omap2/3 architecture specific functions
3 *
4 * Copyright (C) 2008-2009 Nokia Corporation
5 *
6 * Written by Hiroshi DOYU <Hiroshi.DOYU@nokia.com>,
7 * Paul Mundt and Toshihiro Kobayashi
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 */
13
14 #include <linux/err.h>
15 #include <linux/device.h>
16 #include <linux/io.h>
17 #include <linux/jiffies.h>
18 #include <linux/module.h>
19 #include <linux/omap-iommu.h>
20 #include <linux/slab.h>
21 #include <linux/stringify.h>
22 #include <linux/platform_data/iommu-omap.h>
23
24 #include "omap-iommu.h"
25
26 /*
27 * omap2 architecture specific register bit definitions
28 */
29 #define IOMMU_ARCH_VERSION 0x00000011
30
31 /* IRQSTATUS & IRQENABLE */
32 #define MMU_IRQ_MULTIHITFAULT (1 << 4)
33 #define MMU_IRQ_TABLEWALKFAULT (1 << 3)
34 #define MMU_IRQ_EMUMISS (1 << 2)
35 #define MMU_IRQ_TRANSLATIONFAULT (1 << 1)
36 #define MMU_IRQ_TLBMISS (1 << 0)
37
38 #define __MMU_IRQ_FAULT \
39 (MMU_IRQ_MULTIHITFAULT | MMU_IRQ_EMUMISS | MMU_IRQ_TRANSLATIONFAULT)
40 #define MMU_IRQ_MASK \
41 (__MMU_IRQ_FAULT | MMU_IRQ_TABLEWALKFAULT | MMU_IRQ_TLBMISS)
42 #define MMU_IRQ_TWL_MASK (__MMU_IRQ_FAULT | MMU_IRQ_TABLEWALKFAULT)
43 #define MMU_IRQ_TLB_MISS_MASK (__MMU_IRQ_FAULT | MMU_IRQ_TLBMISS)
44
45 /* MMU_CNTL */
46 #define MMU_CNTL_SHIFT 1
47 #define MMU_CNTL_MASK (7 << MMU_CNTL_SHIFT)
48 #define MMU_CNTL_EML_TLB (1 << 3)
49 #define MMU_CNTL_TWL_EN (1 << 2)
50 #define MMU_CNTL_MMU_EN (1 << 1)
51
52 #define get_cam_va_mask(pgsz) \
53 (((pgsz) == MMU_CAM_PGSZ_16M) ? 0xff000000 : \
54 ((pgsz) == MMU_CAM_PGSZ_1M) ? 0xfff00000 : \
55 ((pgsz) == MMU_CAM_PGSZ_64K) ? 0xffff0000 : \
56 ((pgsz) == MMU_CAM_PGSZ_4K) ? 0xfffff000 : 0)
57
58 /* IOMMU errors */
59 #define OMAP_IOMMU_ERR_TLB_MISS (1 << 0)
60 #define OMAP_IOMMU_ERR_TRANS_FAULT (1 << 1)
61 #define OMAP_IOMMU_ERR_EMU_MISS (1 << 2)
62 #define OMAP_IOMMU_ERR_TBLWALK_FAULT (1 << 3)
63 #define OMAP_IOMMU_ERR_MULTIHIT_FAULT (1 << 4)
64
__iommu_set_twl(struct omap_iommu * obj,bool on)65 static void __iommu_set_twl(struct omap_iommu *obj, bool on)
66 {
67 u32 l = iommu_read_reg(obj, MMU_CNTL);
68
69 if (on)
70 iommu_write_reg(obj, MMU_IRQ_TWL_MASK, MMU_IRQENABLE);
71 else
72 iommu_write_reg(obj, MMU_IRQ_TLB_MISS_MASK, MMU_IRQENABLE);
73
74 l &= ~MMU_CNTL_MASK;
75 if (on)
76 l |= (MMU_CNTL_MMU_EN | MMU_CNTL_TWL_EN);
77 else
78 l |= (MMU_CNTL_MMU_EN);
79
80 iommu_write_reg(obj, l, MMU_CNTL);
81 }
82
83
omap2_iommu_enable(struct omap_iommu * obj)84 static int omap2_iommu_enable(struct omap_iommu *obj)
85 {
86 u32 l, pa;
87
88 if (!obj->iopgd || !IS_ALIGNED((u32)obj->iopgd, SZ_16K))
89 return -EINVAL;
90
91 pa = virt_to_phys(obj->iopgd);
92 if (!IS_ALIGNED(pa, SZ_16K))
93 return -EINVAL;
94
95 l = iommu_read_reg(obj, MMU_REVISION);
96 dev_info(obj->dev, "%s: version %d.%d\n", obj->name,
97 (l >> 4) & 0xf, l & 0xf);
98
99 iommu_write_reg(obj, pa, MMU_TTB);
100
101 if (obj->has_bus_err_back)
102 iommu_write_reg(obj, MMU_GP_REG_BUS_ERR_BACK_EN, MMU_GP_REG);
103
104 __iommu_set_twl(obj, true);
105
106 return 0;
107 }
108
omap2_iommu_disable(struct omap_iommu * obj)109 static void omap2_iommu_disable(struct omap_iommu *obj)
110 {
111 u32 l = iommu_read_reg(obj, MMU_CNTL);
112
113 l &= ~MMU_CNTL_MASK;
114 iommu_write_reg(obj, l, MMU_CNTL);
115
116 dev_dbg(obj->dev, "%s is shutting down\n", obj->name);
117 }
118
omap2_iommu_set_twl(struct omap_iommu * obj,bool on)119 static void omap2_iommu_set_twl(struct omap_iommu *obj, bool on)
120 {
121 __iommu_set_twl(obj, false);
122 }
123
omap2_iommu_fault_isr(struct omap_iommu * obj,u32 * ra)124 static u32 omap2_iommu_fault_isr(struct omap_iommu *obj, u32 *ra)
125 {
126 u32 stat, da;
127 u32 errs = 0;
128
129 stat = iommu_read_reg(obj, MMU_IRQSTATUS);
130 stat &= MMU_IRQ_MASK;
131 if (!stat) {
132 *ra = 0;
133 return 0;
134 }
135
136 da = iommu_read_reg(obj, MMU_FAULT_AD);
137 *ra = da;
138
139 if (stat & MMU_IRQ_TLBMISS)
140 errs |= OMAP_IOMMU_ERR_TLB_MISS;
141 if (stat & MMU_IRQ_TRANSLATIONFAULT)
142 errs |= OMAP_IOMMU_ERR_TRANS_FAULT;
143 if (stat & MMU_IRQ_EMUMISS)
144 errs |= OMAP_IOMMU_ERR_EMU_MISS;
145 if (stat & MMU_IRQ_TABLEWALKFAULT)
146 errs |= OMAP_IOMMU_ERR_TBLWALK_FAULT;
147 if (stat & MMU_IRQ_MULTIHITFAULT)
148 errs |= OMAP_IOMMU_ERR_MULTIHIT_FAULT;
149 iommu_write_reg(obj, stat, MMU_IRQSTATUS);
150
151 return errs;
152 }
153
omap2_tlb_read_cr(struct omap_iommu * obj,struct cr_regs * cr)154 static void omap2_tlb_read_cr(struct omap_iommu *obj, struct cr_regs *cr)
155 {
156 cr->cam = iommu_read_reg(obj, MMU_READ_CAM);
157 cr->ram = iommu_read_reg(obj, MMU_READ_RAM);
158 }
159
omap2_tlb_load_cr(struct omap_iommu * obj,struct cr_regs * cr)160 static void omap2_tlb_load_cr(struct omap_iommu *obj, struct cr_regs *cr)
161 {
162 iommu_write_reg(obj, cr->cam | MMU_CAM_V, MMU_CAM);
163 iommu_write_reg(obj, cr->ram, MMU_RAM);
164 }
165
omap2_cr_to_virt(struct cr_regs * cr)166 static u32 omap2_cr_to_virt(struct cr_regs *cr)
167 {
168 u32 page_size = cr->cam & MMU_CAM_PGSZ_MASK;
169 u32 mask = get_cam_va_mask(cr->cam & page_size);
170
171 return cr->cam & mask;
172 }
173
omap2_alloc_cr(struct omap_iommu * obj,struct iotlb_entry * e)174 static struct cr_regs *omap2_alloc_cr(struct omap_iommu *obj,
175 struct iotlb_entry *e)
176 {
177 struct cr_regs *cr;
178
179 if (e->da & ~(get_cam_va_mask(e->pgsz))) {
180 dev_err(obj->dev, "%s:\twrong alignment: %08x\n", __func__,
181 e->da);
182 return ERR_PTR(-EINVAL);
183 }
184
185 cr = kmalloc(sizeof(*cr), GFP_KERNEL);
186 if (!cr)
187 return ERR_PTR(-ENOMEM);
188
189 cr->cam = (e->da & MMU_CAM_VATAG_MASK) | e->prsvd | e->pgsz | e->valid;
190 cr->ram = e->pa | e->endian | e->elsz | e->mixed;
191
192 return cr;
193 }
194
omap2_cr_valid(struct cr_regs * cr)195 static inline int omap2_cr_valid(struct cr_regs *cr)
196 {
197 return cr->cam & MMU_CAM_V;
198 }
199
omap2_get_pte_attr(struct iotlb_entry * e)200 static u32 omap2_get_pte_attr(struct iotlb_entry *e)
201 {
202 u32 attr;
203
204 attr = e->mixed << 5;
205 attr |= e->endian;
206 attr |= e->elsz >> 3;
207 attr <<= (((e->pgsz == MMU_CAM_PGSZ_4K) ||
208 (e->pgsz == MMU_CAM_PGSZ_64K)) ? 0 : 6);
209 return attr;
210 }
211
212 static ssize_t
omap2_dump_cr(struct omap_iommu * obj,struct cr_regs * cr,char * buf)213 omap2_dump_cr(struct omap_iommu *obj, struct cr_regs *cr, char *buf)
214 {
215 char *p = buf;
216
217 /* FIXME: Need more detail analysis of cam/ram */
218 p += sprintf(p, "%08x %08x %01x\n", cr->cam, cr->ram,
219 (cr->cam & MMU_CAM_P) ? 1 : 0);
220
221 return p - buf;
222 }
223
224 #define pr_reg(name) \
225 do { \
226 ssize_t bytes; \
227 const char *str = "%20s: %08x\n"; \
228 const int maxcol = 32; \
229 bytes = snprintf(p, maxcol, str, __stringify(name), \
230 iommu_read_reg(obj, MMU_##name)); \
231 p += bytes; \
232 len -= bytes; \
233 if (len < maxcol) \
234 goto out; \
235 } while (0)
236
237 static ssize_t
omap2_iommu_dump_ctx(struct omap_iommu * obj,char * buf,ssize_t len)238 omap2_iommu_dump_ctx(struct omap_iommu *obj, char *buf, ssize_t len)
239 {
240 char *p = buf;
241
242 pr_reg(REVISION);
243 pr_reg(IRQSTATUS);
244 pr_reg(IRQENABLE);
245 pr_reg(WALKING_ST);
246 pr_reg(CNTL);
247 pr_reg(FAULT_AD);
248 pr_reg(TTB);
249 pr_reg(LOCK);
250 pr_reg(LD_TLB);
251 pr_reg(CAM);
252 pr_reg(RAM);
253 pr_reg(GFLUSH);
254 pr_reg(FLUSH_ENTRY);
255 pr_reg(READ_CAM);
256 pr_reg(READ_RAM);
257 pr_reg(EMU_FAULT_AD);
258 out:
259 return p - buf;
260 }
261
omap2_iommu_save_ctx(struct omap_iommu * obj)262 static void omap2_iommu_save_ctx(struct omap_iommu *obj)
263 {
264 int i;
265 u32 *p = obj->ctx;
266
267 for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) {
268 p[i] = iommu_read_reg(obj, i * sizeof(u32));
269 dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i, p[i]);
270 }
271
272 BUG_ON(p[0] != IOMMU_ARCH_VERSION);
273 }
274
omap2_iommu_restore_ctx(struct omap_iommu * obj)275 static void omap2_iommu_restore_ctx(struct omap_iommu *obj)
276 {
277 int i;
278 u32 *p = obj->ctx;
279
280 for (i = 0; i < (MMU_REG_SIZE / sizeof(u32)); i++) {
281 iommu_write_reg(obj, p[i], i * sizeof(u32));
282 dev_dbg(obj->dev, "%s\t[%02d] %08x\n", __func__, i, p[i]);
283 }
284
285 BUG_ON(p[0] != IOMMU_ARCH_VERSION);
286 }
287
omap2_cr_to_e(struct cr_regs * cr,struct iotlb_entry * e)288 static void omap2_cr_to_e(struct cr_regs *cr, struct iotlb_entry *e)
289 {
290 e->da = cr->cam & MMU_CAM_VATAG_MASK;
291 e->pa = cr->ram & MMU_RAM_PADDR_MASK;
292 e->valid = cr->cam & MMU_CAM_V;
293 e->pgsz = cr->cam & MMU_CAM_PGSZ_MASK;
294 e->endian = cr->ram & MMU_RAM_ENDIAN_MASK;
295 e->elsz = cr->ram & MMU_RAM_ELSZ_MASK;
296 e->mixed = cr->ram & MMU_RAM_MIXED;
297 }
298
299 static const struct iommu_functions omap2_iommu_ops = {
300 .version = IOMMU_ARCH_VERSION,
301
302 .enable = omap2_iommu_enable,
303 .disable = omap2_iommu_disable,
304 .set_twl = omap2_iommu_set_twl,
305 .fault_isr = omap2_iommu_fault_isr,
306
307 .tlb_read_cr = omap2_tlb_read_cr,
308 .tlb_load_cr = omap2_tlb_load_cr,
309
310 .cr_to_e = omap2_cr_to_e,
311 .cr_to_virt = omap2_cr_to_virt,
312 .alloc_cr = omap2_alloc_cr,
313 .cr_valid = omap2_cr_valid,
314 .dump_cr = omap2_dump_cr,
315
316 .get_pte_attr = omap2_get_pte_attr,
317
318 .save_ctx = omap2_iommu_save_ctx,
319 .restore_ctx = omap2_iommu_restore_ctx,
320 .dump_ctx = omap2_iommu_dump_ctx,
321 };
322
omap2_iommu_init(void)323 static int __init omap2_iommu_init(void)
324 {
325 return omap_install_iommu_arch(&omap2_iommu_ops);
326 }
327 module_init(omap2_iommu_init);
328
omap2_iommu_exit(void)329 static void __exit omap2_iommu_exit(void)
330 {
331 omap_uninstall_iommu_arch(&omap2_iommu_ops);
332 }
333 module_exit(omap2_iommu_exit);
334
335 MODULE_AUTHOR("Hiroshi DOYU, Paul Mundt and Toshihiro Kobayashi");
336 MODULE_DESCRIPTION("omap iommu: omap2/3 architecture specific functions");
337 MODULE_LICENSE("GPL v2");
338