xref: /openbmc/linux/drivers/iommu/mtk_iommu.c (revision 31eeb6b0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2015-2016 MediaTek Inc.
4  * Author: Yong Wu <yong.wu@mediatek.com>
5  */
6 #include <linux/bitfield.h>
7 #include <linux/bug.h>
8 #include <linux/clk.h>
9 #include <linux/component.h>
10 #include <linux/device.h>
11 #include <linux/dma-direct.h>
12 #include <linux/err.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/iommu.h>
16 #include <linux/iopoll.h>
17 #include <linux/list.h>
18 #include <linux/mfd/syscon.h>
19 #include <linux/module.h>
20 #include <linux/of_address.h>
21 #include <linux/of_irq.h>
22 #include <linux/of_platform.h>
23 #include <linux/platform_device.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/regmap.h>
26 #include <linux/slab.h>
27 #include <linux/spinlock.h>
28 #include <linux/soc/mediatek/infracfg.h>
29 #include <asm/barrier.h>
30 #include <soc/mediatek/smi.h>
31 
32 #include "mtk_iommu.h"
33 
34 #define REG_MMU_PT_BASE_ADDR			0x000
35 #define MMU_PT_ADDR_MASK			GENMASK(31, 7)
36 
37 #define REG_MMU_INVALIDATE			0x020
38 #define F_ALL_INVLD				0x2
39 #define F_MMU_INV_RANGE				0x1
40 
41 #define REG_MMU_INVLD_START_A			0x024
42 #define REG_MMU_INVLD_END_A			0x028
43 
44 #define REG_MMU_INV_SEL_GEN2			0x02c
45 #define REG_MMU_INV_SEL_GEN1			0x038
46 #define F_INVLD_EN0				BIT(0)
47 #define F_INVLD_EN1				BIT(1)
48 
49 #define REG_MMU_MISC_CTRL			0x048
50 #define F_MMU_IN_ORDER_WR_EN_MASK		(BIT(1) | BIT(17))
51 #define F_MMU_STANDARD_AXI_MODE_MASK		(BIT(3) | BIT(19))
52 
53 #define REG_MMU_DCM_DIS				0x050
54 #define REG_MMU_WR_LEN_CTRL			0x054
55 #define F_MMU_WR_THROT_DIS_MASK			(BIT(5) | BIT(21))
56 
57 #define REG_MMU_CTRL_REG			0x110
58 #define F_MMU_TF_PROT_TO_PROGRAM_ADDR		(2 << 4)
59 #define F_MMU_PREFETCH_RT_REPLACE_MOD		BIT(4)
60 #define F_MMU_TF_PROT_TO_PROGRAM_ADDR_MT8173	(2 << 5)
61 
62 #define REG_MMU_IVRP_PADDR			0x114
63 
64 #define REG_MMU_VLD_PA_RNG			0x118
65 #define F_MMU_VLD_PA_RNG(EA, SA)		(((EA) << 8) | (SA))
66 
67 #define REG_MMU_INT_CONTROL0			0x120
68 #define F_L2_MULIT_HIT_EN			BIT(0)
69 #define F_TABLE_WALK_FAULT_INT_EN		BIT(1)
70 #define F_PREETCH_FIFO_OVERFLOW_INT_EN		BIT(2)
71 #define F_MISS_FIFO_OVERFLOW_INT_EN		BIT(3)
72 #define F_PREFETCH_FIFO_ERR_INT_EN		BIT(5)
73 #define F_MISS_FIFO_ERR_INT_EN			BIT(6)
74 #define F_INT_CLR_BIT				BIT(12)
75 
76 #define REG_MMU_INT_MAIN_CONTROL		0x124
77 						/* mmu0 | mmu1 */
78 #define F_INT_TRANSLATION_FAULT			(BIT(0) | BIT(7))
79 #define F_INT_MAIN_MULTI_HIT_FAULT		(BIT(1) | BIT(8))
80 #define F_INT_INVALID_PA_FAULT			(BIT(2) | BIT(9))
81 #define F_INT_ENTRY_REPLACEMENT_FAULT		(BIT(3) | BIT(10))
82 #define F_INT_TLB_MISS_FAULT			(BIT(4) | BIT(11))
83 #define F_INT_MISS_TRANSACTION_FIFO_FAULT	(BIT(5) | BIT(12))
84 #define F_INT_PRETETCH_TRANSATION_FIFO_FAULT	(BIT(6) | BIT(13))
85 
86 #define REG_MMU_CPE_DONE			0x12C
87 
88 #define REG_MMU_FAULT_ST1			0x134
89 #define F_REG_MMU0_FAULT_MASK			GENMASK(6, 0)
90 #define F_REG_MMU1_FAULT_MASK			GENMASK(13, 7)
91 
92 #define REG_MMU0_FAULT_VA			0x13c
93 #define F_MMU_INVAL_VA_31_12_MASK		GENMASK(31, 12)
94 #define F_MMU_INVAL_VA_34_32_MASK		GENMASK(11, 9)
95 #define F_MMU_INVAL_PA_34_32_MASK		GENMASK(8, 6)
96 #define F_MMU_FAULT_VA_WRITE_BIT		BIT(1)
97 #define F_MMU_FAULT_VA_LAYER_BIT		BIT(0)
98 
99 #define REG_MMU0_INVLD_PA			0x140
100 #define REG_MMU1_FAULT_VA			0x144
101 #define REG_MMU1_INVLD_PA			0x148
102 #define REG_MMU0_INT_ID				0x150
103 #define REG_MMU1_INT_ID				0x154
104 #define F_MMU_INT_ID_COMM_ID(a)			(((a) >> 9) & 0x7)
105 #define F_MMU_INT_ID_SUB_COMM_ID(a)		(((a) >> 7) & 0x3)
106 #define F_MMU_INT_ID_LARB_ID(a)			(((a) >> 7) & 0x7)
107 #define F_MMU_INT_ID_PORT_ID(a)			(((a) >> 2) & 0x1f)
108 
109 #define MTK_PROTECT_PA_ALIGN			256
110 
111 #define HAS_4GB_MODE			BIT(0)
112 /* HW will use the EMI clock if there isn't the "bclk". */
113 #define HAS_BCLK			BIT(1)
114 #define HAS_VLD_PA_RNG			BIT(2)
115 #define RESET_AXI			BIT(3)
116 #define OUT_ORDER_WR_EN			BIT(4)
117 #define HAS_SUB_COMM			BIT(5)
118 #define WR_THROT_EN			BIT(6)
119 #define HAS_LEGACY_IVRP_PADDR		BIT(7)
120 #define IOVA_34_EN			BIT(8)
121 
122 #define MTK_IOMMU_HAS_FLAG(pdata, _x) \
123 		((((pdata)->flags) & (_x)) == (_x))
124 
125 struct mtk_iommu_domain {
126 	struct io_pgtable_cfg		cfg;
127 	struct io_pgtable_ops		*iop;
128 
129 	struct mtk_iommu_data		*data;
130 	struct iommu_domain		domain;
131 };
132 
133 static const struct iommu_ops mtk_iommu_ops;
134 
135 static int mtk_iommu_hw_init(const struct mtk_iommu_data *data);
136 
137 #define MTK_IOMMU_TLB_ADDR(iova) ({					\
138 	dma_addr_t _addr = iova;					\
139 	((lower_32_bits(_addr) & GENMASK(31, 12)) | upper_32_bits(_addr));\
140 })
141 
142 /*
143  * In M4U 4GB mode, the physical address is remapped as below:
144  *
145  * CPU Physical address:
146  * ====================
147  *
148  * 0      1G       2G     3G       4G     5G
149  * |---A---|---B---|---C---|---D---|---E---|
150  * +--I/O--+------------Memory-------------+
151  *
152  * IOMMU output physical address:
153  *  =============================
154  *
155  *                                 4G      5G     6G      7G      8G
156  *                                 |---E---|---B---|---C---|---D---|
157  *                                 +------------Memory-------------+
158  *
159  * The Region 'A'(I/O) can NOT be mapped by M4U; For Region 'B'/'C'/'D', the
160  * bit32 of the CPU physical address always is needed to set, and for Region
161  * 'E', the CPU physical address keep as is.
162  * Additionally, The iommu consumers always use the CPU phyiscal address.
163  */
164 #define MTK_IOMMU_4GB_MODE_REMAP_BASE	 0x140000000UL
165 
166 static LIST_HEAD(m4ulist);	/* List all the M4U HWs */
167 
168 #define for_each_m4u(data)	list_for_each_entry(data, &m4ulist, list)
169 
170 struct mtk_iommu_iova_region {
171 	dma_addr_t		iova_base;
172 	unsigned long long	size;
173 };
174 
175 static const struct mtk_iommu_iova_region single_domain[] = {
176 	{.iova_base = 0,		.size = SZ_4G},
177 };
178 
179 static const struct mtk_iommu_iova_region mt8192_multi_dom[] = {
180 	{ .iova_base = 0x0,		.size = SZ_4G},		/* disp: 0 ~ 4G */
181 	#if IS_ENABLED(CONFIG_ARCH_DMA_ADDR_T_64BIT)
182 	{ .iova_base = SZ_4G,		.size = SZ_4G},		/* vdec: 4G ~ 8G */
183 	{ .iova_base = SZ_4G * 2,	.size = SZ_4G},		/* CAM/MDP: 8G ~ 12G */
184 	{ .iova_base = 0x240000000ULL,	.size = 0x4000000},	/* CCU0 */
185 	{ .iova_base = 0x244000000ULL,	.size = 0x4000000},	/* CCU1 */
186 	#endif
187 };
188 
189 /*
190  * There may be 1 or 2 M4U HWs, But we always expect they are in the same domain
191  * for the performance.
192  *
193  * Here always return the mtk_iommu_data of the first probed M4U where the
194  * iommu domain information is recorded.
195  */
196 static struct mtk_iommu_data *mtk_iommu_get_m4u_data(void)
197 {
198 	struct mtk_iommu_data *data;
199 
200 	for_each_m4u(data)
201 		return data;
202 
203 	return NULL;
204 }
205 
206 static struct mtk_iommu_domain *to_mtk_domain(struct iommu_domain *dom)
207 {
208 	return container_of(dom, struct mtk_iommu_domain, domain);
209 }
210 
211 static void mtk_iommu_tlb_flush_all(struct mtk_iommu_data *data)
212 {
213 	for_each_m4u(data) {
214 		if (pm_runtime_get_if_in_use(data->dev) <= 0)
215 			continue;
216 
217 		writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
218 			       data->base + data->plat_data->inv_sel_reg);
219 		writel_relaxed(F_ALL_INVLD, data->base + REG_MMU_INVALIDATE);
220 		wmb(); /* Make sure the tlb flush all done */
221 
222 		pm_runtime_put(data->dev);
223 	}
224 }
225 
226 static void mtk_iommu_tlb_flush_range_sync(unsigned long iova, size_t size,
227 					   size_t granule,
228 					   struct mtk_iommu_data *data)
229 {
230 	bool has_pm = !!data->dev->pm_domain;
231 	unsigned long flags;
232 	int ret;
233 	u32 tmp;
234 
235 	for_each_m4u(data) {
236 		if (has_pm) {
237 			if (pm_runtime_get_if_in_use(data->dev) <= 0)
238 				continue;
239 		}
240 
241 		spin_lock_irqsave(&data->tlb_lock, flags);
242 		writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
243 			       data->base + data->plat_data->inv_sel_reg);
244 
245 		writel_relaxed(MTK_IOMMU_TLB_ADDR(iova),
246 			       data->base + REG_MMU_INVLD_START_A);
247 		writel_relaxed(MTK_IOMMU_TLB_ADDR(iova + size - 1),
248 			       data->base + REG_MMU_INVLD_END_A);
249 		writel_relaxed(F_MMU_INV_RANGE,
250 			       data->base + REG_MMU_INVALIDATE);
251 
252 		/* tlb sync */
253 		ret = readl_poll_timeout_atomic(data->base + REG_MMU_CPE_DONE,
254 						tmp, tmp != 0, 10, 1000);
255 		if (ret) {
256 			dev_warn(data->dev,
257 				 "Partial TLB flush timed out, falling back to full flush\n");
258 			mtk_iommu_tlb_flush_all(data);
259 		}
260 		/* Clear the CPE status */
261 		writel_relaxed(0, data->base + REG_MMU_CPE_DONE);
262 		spin_unlock_irqrestore(&data->tlb_lock, flags);
263 
264 		if (has_pm)
265 			pm_runtime_put(data->dev);
266 	}
267 }
268 
269 static irqreturn_t mtk_iommu_isr(int irq, void *dev_id)
270 {
271 	struct mtk_iommu_data *data = dev_id;
272 	struct mtk_iommu_domain *dom = data->m4u_dom;
273 	unsigned int fault_larb, fault_port, sub_comm = 0;
274 	u32 int_state, regval, va34_32, pa34_32;
275 	u64 fault_iova, fault_pa;
276 	bool layer, write;
277 
278 	/* Read error info from registers */
279 	int_state = readl_relaxed(data->base + REG_MMU_FAULT_ST1);
280 	if (int_state & F_REG_MMU0_FAULT_MASK) {
281 		regval = readl_relaxed(data->base + REG_MMU0_INT_ID);
282 		fault_iova = readl_relaxed(data->base + REG_MMU0_FAULT_VA);
283 		fault_pa = readl_relaxed(data->base + REG_MMU0_INVLD_PA);
284 	} else {
285 		regval = readl_relaxed(data->base + REG_MMU1_INT_ID);
286 		fault_iova = readl_relaxed(data->base + REG_MMU1_FAULT_VA);
287 		fault_pa = readl_relaxed(data->base + REG_MMU1_INVLD_PA);
288 	}
289 	layer = fault_iova & F_MMU_FAULT_VA_LAYER_BIT;
290 	write = fault_iova & F_MMU_FAULT_VA_WRITE_BIT;
291 	if (MTK_IOMMU_HAS_FLAG(data->plat_data, IOVA_34_EN)) {
292 		va34_32 = FIELD_GET(F_MMU_INVAL_VA_34_32_MASK, fault_iova);
293 		pa34_32 = FIELD_GET(F_MMU_INVAL_PA_34_32_MASK, fault_iova);
294 		fault_iova = fault_iova & F_MMU_INVAL_VA_31_12_MASK;
295 		fault_iova |= (u64)va34_32 << 32;
296 		fault_pa |= (u64)pa34_32 << 32;
297 	}
298 
299 	fault_port = F_MMU_INT_ID_PORT_ID(regval);
300 	if (MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_SUB_COMM)) {
301 		fault_larb = F_MMU_INT_ID_COMM_ID(regval);
302 		sub_comm = F_MMU_INT_ID_SUB_COMM_ID(regval);
303 	} else {
304 		fault_larb = F_MMU_INT_ID_LARB_ID(regval);
305 	}
306 	fault_larb = data->plat_data->larbid_remap[fault_larb][sub_comm];
307 
308 	if (report_iommu_fault(&dom->domain, data->dev, fault_iova,
309 			       write ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ)) {
310 		dev_err_ratelimited(
311 			data->dev,
312 			"fault type=0x%x iova=0x%llx pa=0x%llx larb=%d port=%d layer=%d %s\n",
313 			int_state, fault_iova, fault_pa, fault_larb, fault_port,
314 			layer, write ? "write" : "read");
315 	}
316 
317 	/* Interrupt clear */
318 	regval = readl_relaxed(data->base + REG_MMU_INT_CONTROL0);
319 	regval |= F_INT_CLR_BIT;
320 	writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL0);
321 
322 	mtk_iommu_tlb_flush_all(data);
323 
324 	return IRQ_HANDLED;
325 }
326 
327 static int mtk_iommu_get_domain_id(struct device *dev,
328 				   const struct mtk_iommu_plat_data *plat_data)
329 {
330 	const struct mtk_iommu_iova_region *rgn = plat_data->iova_region;
331 	const struct bus_dma_region *dma_rgn = dev->dma_range_map;
332 	int i, candidate = -1;
333 	dma_addr_t dma_end;
334 
335 	if (!dma_rgn || plat_data->iova_region_nr == 1)
336 		return 0;
337 
338 	dma_end = dma_rgn->dma_start + dma_rgn->size - 1;
339 	for (i = 0; i < plat_data->iova_region_nr; i++, rgn++) {
340 		/* Best fit. */
341 		if (dma_rgn->dma_start == rgn->iova_base &&
342 		    dma_end == rgn->iova_base + rgn->size - 1)
343 			return i;
344 		/* ok if it is inside this region. */
345 		if (dma_rgn->dma_start >= rgn->iova_base &&
346 		    dma_end < rgn->iova_base + rgn->size)
347 			candidate = i;
348 	}
349 
350 	if (candidate >= 0)
351 		return candidate;
352 	dev_err(dev, "Can NOT find the iommu domain id(%pad 0x%llx).\n",
353 		&dma_rgn->dma_start, dma_rgn->size);
354 	return -EINVAL;
355 }
356 
357 static void mtk_iommu_config(struct mtk_iommu_data *data, struct device *dev,
358 			     bool enable, unsigned int domid)
359 {
360 	struct mtk_smi_larb_iommu    *larb_mmu;
361 	unsigned int                 larbid, portid;
362 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
363 	const struct mtk_iommu_iova_region *region;
364 	int i;
365 
366 	for (i = 0; i < fwspec->num_ids; ++i) {
367 		larbid = MTK_M4U_TO_LARB(fwspec->ids[i]);
368 		portid = MTK_M4U_TO_PORT(fwspec->ids[i]);
369 
370 		larb_mmu = &data->larb_imu[larbid];
371 
372 		region = data->plat_data->iova_region + domid;
373 		larb_mmu->bank[portid] = upper_32_bits(region->iova_base);
374 
375 		dev_dbg(dev, "%s iommu for larb(%s) port %d dom %d bank %d.\n",
376 			enable ? "enable" : "disable", dev_name(larb_mmu->dev),
377 			portid, domid, larb_mmu->bank[portid]);
378 
379 		if (enable)
380 			larb_mmu->mmu |= MTK_SMI_MMU_EN(portid);
381 		else
382 			larb_mmu->mmu &= ~MTK_SMI_MMU_EN(portid);
383 	}
384 }
385 
386 static int mtk_iommu_domain_finalise(struct mtk_iommu_domain *dom,
387 				     struct mtk_iommu_data *data,
388 				     unsigned int domid)
389 {
390 	const struct mtk_iommu_iova_region *region;
391 
392 	/* Use the exist domain as there is only one pgtable here. */
393 	if (data->m4u_dom) {
394 		dom->iop = data->m4u_dom->iop;
395 		dom->cfg = data->m4u_dom->cfg;
396 		dom->domain.pgsize_bitmap = data->m4u_dom->cfg.pgsize_bitmap;
397 		goto update_iova_region;
398 	}
399 
400 	dom->cfg = (struct io_pgtable_cfg) {
401 		.quirks = IO_PGTABLE_QUIRK_ARM_NS |
402 			IO_PGTABLE_QUIRK_NO_PERMS |
403 			IO_PGTABLE_QUIRK_ARM_MTK_EXT,
404 		.pgsize_bitmap = mtk_iommu_ops.pgsize_bitmap,
405 		.ias = MTK_IOMMU_HAS_FLAG(data->plat_data, IOVA_34_EN) ? 34 : 32,
406 		.iommu_dev = data->dev,
407 	};
408 
409 	if (MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE))
410 		dom->cfg.oas = data->enable_4GB ? 33 : 32;
411 	else
412 		dom->cfg.oas = 35;
413 
414 	dom->iop = alloc_io_pgtable_ops(ARM_V7S, &dom->cfg, data);
415 	if (!dom->iop) {
416 		dev_err(data->dev, "Failed to alloc io pgtable\n");
417 		return -EINVAL;
418 	}
419 
420 	/* Update our support page sizes bitmap */
421 	dom->domain.pgsize_bitmap = dom->cfg.pgsize_bitmap;
422 
423 update_iova_region:
424 	/* Update the iova region for this domain */
425 	region = data->plat_data->iova_region + domid;
426 	dom->domain.geometry.aperture_start = region->iova_base;
427 	dom->domain.geometry.aperture_end = region->iova_base + region->size - 1;
428 	dom->domain.geometry.force_aperture = true;
429 	return 0;
430 }
431 
432 static struct iommu_domain *mtk_iommu_domain_alloc(unsigned type)
433 {
434 	struct mtk_iommu_domain *dom;
435 
436 	if (type != IOMMU_DOMAIN_DMA)
437 		return NULL;
438 
439 	dom = kzalloc(sizeof(*dom), GFP_KERNEL);
440 	if (!dom)
441 		return NULL;
442 
443 	return &dom->domain;
444 }
445 
446 static void mtk_iommu_domain_free(struct iommu_domain *domain)
447 {
448 	kfree(to_mtk_domain(domain));
449 }
450 
451 static int mtk_iommu_attach_device(struct iommu_domain *domain,
452 				   struct device *dev)
453 {
454 	struct mtk_iommu_data *data = dev_iommu_priv_get(dev);
455 	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
456 	struct device *m4udev = data->dev;
457 	int ret, domid;
458 
459 	domid = mtk_iommu_get_domain_id(dev, data->plat_data);
460 	if (domid < 0)
461 		return domid;
462 
463 	if (!dom->data) {
464 		if (mtk_iommu_domain_finalise(dom, data, domid))
465 			return -ENODEV;
466 		dom->data = data;
467 	}
468 
469 	if (!data->m4u_dom) { /* Initialize the M4U HW */
470 		ret = pm_runtime_resume_and_get(m4udev);
471 		if (ret < 0)
472 			return ret;
473 
474 		ret = mtk_iommu_hw_init(data);
475 		if (ret) {
476 			pm_runtime_put(m4udev);
477 			return ret;
478 		}
479 		data->m4u_dom = dom;
480 		writel(dom->cfg.arm_v7s_cfg.ttbr & MMU_PT_ADDR_MASK,
481 		       data->base + REG_MMU_PT_BASE_ADDR);
482 
483 		pm_runtime_put(m4udev);
484 	}
485 
486 	mtk_iommu_config(data, dev, true, domid);
487 	return 0;
488 }
489 
490 static void mtk_iommu_detach_device(struct iommu_domain *domain,
491 				    struct device *dev)
492 {
493 	struct mtk_iommu_data *data = dev_iommu_priv_get(dev);
494 
495 	mtk_iommu_config(data, dev, false, 0);
496 }
497 
498 static int mtk_iommu_map(struct iommu_domain *domain, unsigned long iova,
499 			 phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
500 {
501 	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
502 
503 	/* The "4GB mode" M4U physically can not use the lower remap of Dram. */
504 	if (dom->data->enable_4GB)
505 		paddr |= BIT_ULL(32);
506 
507 	/* Synchronize with the tlb_lock */
508 	return dom->iop->map(dom->iop, iova, paddr, size, prot, gfp);
509 }
510 
511 static size_t mtk_iommu_unmap(struct iommu_domain *domain,
512 			      unsigned long iova, size_t size,
513 			      struct iommu_iotlb_gather *gather)
514 {
515 	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
516 
517 	iommu_iotlb_gather_add_range(gather, iova, size);
518 	return dom->iop->unmap(dom->iop, iova, size, gather);
519 }
520 
521 static void mtk_iommu_flush_iotlb_all(struct iommu_domain *domain)
522 {
523 	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
524 
525 	mtk_iommu_tlb_flush_all(dom->data);
526 }
527 
528 static void mtk_iommu_iotlb_sync(struct iommu_domain *domain,
529 				 struct iommu_iotlb_gather *gather)
530 {
531 	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
532 	size_t length = gather->end - gather->start + 1;
533 
534 	mtk_iommu_tlb_flush_range_sync(gather->start, length, gather->pgsize,
535 				       dom->data);
536 }
537 
538 static void mtk_iommu_sync_map(struct iommu_domain *domain, unsigned long iova,
539 			       size_t size)
540 {
541 	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
542 
543 	mtk_iommu_tlb_flush_range_sync(iova, size, size, dom->data);
544 }
545 
546 static phys_addr_t mtk_iommu_iova_to_phys(struct iommu_domain *domain,
547 					  dma_addr_t iova)
548 {
549 	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
550 	phys_addr_t pa;
551 
552 	pa = dom->iop->iova_to_phys(dom->iop, iova);
553 	if (IS_ENABLED(CONFIG_PHYS_ADDR_T_64BIT) &&
554 	    dom->data->enable_4GB &&
555 	    pa >= MTK_IOMMU_4GB_MODE_REMAP_BASE)
556 		pa &= ~BIT_ULL(32);
557 
558 	return pa;
559 }
560 
561 static struct iommu_device *mtk_iommu_probe_device(struct device *dev)
562 {
563 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
564 	struct mtk_iommu_data *data;
565 
566 	if (!fwspec || fwspec->ops != &mtk_iommu_ops)
567 		return ERR_PTR(-ENODEV); /* Not a iommu client device */
568 
569 	data = dev_iommu_priv_get(dev);
570 
571 	return &data->iommu;
572 }
573 
574 static void mtk_iommu_release_device(struct device *dev)
575 {
576 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
577 
578 	if (!fwspec || fwspec->ops != &mtk_iommu_ops)
579 		return;
580 
581 	iommu_fwspec_free(dev);
582 }
583 
584 static struct iommu_group *mtk_iommu_device_group(struct device *dev)
585 {
586 	struct mtk_iommu_data *data = mtk_iommu_get_m4u_data();
587 	struct iommu_group *group;
588 	int domid;
589 
590 	if (!data)
591 		return ERR_PTR(-ENODEV);
592 
593 	domid = mtk_iommu_get_domain_id(dev, data->plat_data);
594 	if (domid < 0)
595 		return ERR_PTR(domid);
596 
597 	group = data->m4u_group[domid];
598 	if (!group) {
599 		group = iommu_group_alloc();
600 		if (!IS_ERR(group))
601 			data->m4u_group[domid] = group;
602 	} else {
603 		iommu_group_ref_get(group);
604 	}
605 	return group;
606 }
607 
608 static int mtk_iommu_of_xlate(struct device *dev, struct of_phandle_args *args)
609 {
610 	struct platform_device *m4updev;
611 
612 	if (args->args_count != 1) {
613 		dev_err(dev, "invalid #iommu-cells(%d) property for IOMMU\n",
614 			args->args_count);
615 		return -EINVAL;
616 	}
617 
618 	if (!dev_iommu_priv_get(dev)) {
619 		/* Get the m4u device */
620 		m4updev = of_find_device_by_node(args->np);
621 		if (WARN_ON(!m4updev))
622 			return -EINVAL;
623 
624 		dev_iommu_priv_set(dev, platform_get_drvdata(m4updev));
625 	}
626 
627 	return iommu_fwspec_add_ids(dev, args->args, 1);
628 }
629 
630 static void mtk_iommu_get_resv_regions(struct device *dev,
631 				       struct list_head *head)
632 {
633 	struct mtk_iommu_data *data = dev_iommu_priv_get(dev);
634 	unsigned int domid = mtk_iommu_get_domain_id(dev, data->plat_data), i;
635 	const struct mtk_iommu_iova_region *resv, *curdom;
636 	struct iommu_resv_region *region;
637 	int prot = IOMMU_WRITE | IOMMU_READ;
638 
639 	if ((int)domid < 0)
640 		return;
641 	curdom = data->plat_data->iova_region + domid;
642 	for (i = 0; i < data->plat_data->iova_region_nr; i++) {
643 		resv = data->plat_data->iova_region + i;
644 
645 		/* Only reserve when the region is inside the current domain */
646 		if (resv->iova_base <= curdom->iova_base ||
647 		    resv->iova_base + resv->size >= curdom->iova_base + curdom->size)
648 			continue;
649 
650 		region = iommu_alloc_resv_region(resv->iova_base, resv->size,
651 						 prot, IOMMU_RESV_RESERVED);
652 		if (!region)
653 			return;
654 
655 		list_add_tail(&region->list, head);
656 	}
657 }
658 
659 static const struct iommu_ops mtk_iommu_ops = {
660 	.domain_alloc	= mtk_iommu_domain_alloc,
661 	.domain_free	= mtk_iommu_domain_free,
662 	.attach_dev	= mtk_iommu_attach_device,
663 	.detach_dev	= mtk_iommu_detach_device,
664 	.map		= mtk_iommu_map,
665 	.unmap		= mtk_iommu_unmap,
666 	.flush_iotlb_all = mtk_iommu_flush_iotlb_all,
667 	.iotlb_sync	= mtk_iommu_iotlb_sync,
668 	.iotlb_sync_map	= mtk_iommu_sync_map,
669 	.iova_to_phys	= mtk_iommu_iova_to_phys,
670 	.probe_device	= mtk_iommu_probe_device,
671 	.release_device	= mtk_iommu_release_device,
672 	.device_group	= mtk_iommu_device_group,
673 	.of_xlate	= mtk_iommu_of_xlate,
674 	.get_resv_regions = mtk_iommu_get_resv_regions,
675 	.put_resv_regions = generic_iommu_put_resv_regions,
676 	.pgsize_bitmap	= SZ_4K | SZ_64K | SZ_1M | SZ_16M,
677 	.owner		= THIS_MODULE,
678 };
679 
680 static int mtk_iommu_hw_init(const struct mtk_iommu_data *data)
681 {
682 	u32 regval;
683 
684 	if (data->plat_data->m4u_plat == M4U_MT8173) {
685 		regval = F_MMU_PREFETCH_RT_REPLACE_MOD |
686 			 F_MMU_TF_PROT_TO_PROGRAM_ADDR_MT8173;
687 	} else {
688 		regval = readl_relaxed(data->base + REG_MMU_CTRL_REG);
689 		regval |= F_MMU_TF_PROT_TO_PROGRAM_ADDR;
690 	}
691 	writel_relaxed(regval, data->base + REG_MMU_CTRL_REG);
692 
693 	regval = F_L2_MULIT_HIT_EN |
694 		F_TABLE_WALK_FAULT_INT_EN |
695 		F_PREETCH_FIFO_OVERFLOW_INT_EN |
696 		F_MISS_FIFO_OVERFLOW_INT_EN |
697 		F_PREFETCH_FIFO_ERR_INT_EN |
698 		F_MISS_FIFO_ERR_INT_EN;
699 	writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL0);
700 
701 	regval = F_INT_TRANSLATION_FAULT |
702 		F_INT_MAIN_MULTI_HIT_FAULT |
703 		F_INT_INVALID_PA_FAULT |
704 		F_INT_ENTRY_REPLACEMENT_FAULT |
705 		F_INT_TLB_MISS_FAULT |
706 		F_INT_MISS_TRANSACTION_FIFO_FAULT |
707 		F_INT_PRETETCH_TRANSATION_FIFO_FAULT;
708 	writel_relaxed(regval, data->base + REG_MMU_INT_MAIN_CONTROL);
709 
710 	if (MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_LEGACY_IVRP_PADDR))
711 		regval = (data->protect_base >> 1) | (data->enable_4GB << 31);
712 	else
713 		regval = lower_32_bits(data->protect_base) |
714 			 upper_32_bits(data->protect_base);
715 	writel_relaxed(regval, data->base + REG_MMU_IVRP_PADDR);
716 
717 	if (data->enable_4GB &&
718 	    MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_VLD_PA_RNG)) {
719 		/*
720 		 * If 4GB mode is enabled, the validate PA range is from
721 		 * 0x1_0000_0000 to 0x1_ffff_ffff. here record bit[32:30].
722 		 */
723 		regval = F_MMU_VLD_PA_RNG(7, 4);
724 		writel_relaxed(regval, data->base + REG_MMU_VLD_PA_RNG);
725 	}
726 	writel_relaxed(0, data->base + REG_MMU_DCM_DIS);
727 	if (MTK_IOMMU_HAS_FLAG(data->plat_data, WR_THROT_EN)) {
728 		/* write command throttling mode */
729 		regval = readl_relaxed(data->base + REG_MMU_WR_LEN_CTRL);
730 		regval &= ~F_MMU_WR_THROT_DIS_MASK;
731 		writel_relaxed(regval, data->base + REG_MMU_WR_LEN_CTRL);
732 	}
733 
734 	if (MTK_IOMMU_HAS_FLAG(data->plat_data, RESET_AXI)) {
735 		/* The register is called STANDARD_AXI_MODE in this case */
736 		regval = 0;
737 	} else {
738 		regval = readl_relaxed(data->base + REG_MMU_MISC_CTRL);
739 		regval &= ~F_MMU_STANDARD_AXI_MODE_MASK;
740 		if (MTK_IOMMU_HAS_FLAG(data->plat_data, OUT_ORDER_WR_EN))
741 			regval &= ~F_MMU_IN_ORDER_WR_EN_MASK;
742 	}
743 	writel_relaxed(regval, data->base + REG_MMU_MISC_CTRL);
744 
745 	if (devm_request_irq(data->dev, data->irq, mtk_iommu_isr, 0,
746 			     dev_name(data->dev), (void *)data)) {
747 		writel_relaxed(0, data->base + REG_MMU_PT_BASE_ADDR);
748 		dev_err(data->dev, "Failed @ IRQ-%d Request\n", data->irq);
749 		return -ENODEV;
750 	}
751 
752 	return 0;
753 }
754 
755 static const struct component_master_ops mtk_iommu_com_ops = {
756 	.bind		= mtk_iommu_bind,
757 	.unbind		= mtk_iommu_unbind,
758 };
759 
760 static int mtk_iommu_probe(struct platform_device *pdev)
761 {
762 	struct mtk_iommu_data   *data;
763 	struct device           *dev = &pdev->dev;
764 	struct device_node	*larbnode, *smicomm_node;
765 	struct platform_device	*plarbdev;
766 	struct device_link	*link;
767 	struct resource         *res;
768 	resource_size_t		ioaddr;
769 	struct component_match  *match = NULL;
770 	struct regmap		*infracfg;
771 	void                    *protect;
772 	int                     i, larb_nr, ret;
773 	u32			val;
774 	char                    *p;
775 
776 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
777 	if (!data)
778 		return -ENOMEM;
779 	data->dev = dev;
780 	data->plat_data = of_device_get_match_data(dev);
781 
782 	/* Protect memory. HW will access here while translation fault.*/
783 	protect = devm_kzalloc(dev, MTK_PROTECT_PA_ALIGN * 2, GFP_KERNEL);
784 	if (!protect)
785 		return -ENOMEM;
786 	data->protect_base = ALIGN(virt_to_phys(protect), MTK_PROTECT_PA_ALIGN);
787 
788 	if (MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_4GB_MODE)) {
789 		switch (data->plat_data->m4u_plat) {
790 		case M4U_MT2712:
791 			p = "mediatek,mt2712-infracfg";
792 			break;
793 		case M4U_MT8173:
794 			p = "mediatek,mt8173-infracfg";
795 			break;
796 		default:
797 			p = NULL;
798 		}
799 
800 		infracfg = syscon_regmap_lookup_by_compatible(p);
801 
802 		if (IS_ERR(infracfg))
803 			return PTR_ERR(infracfg);
804 
805 		ret = regmap_read(infracfg, REG_INFRA_MISC, &val);
806 		if (ret)
807 			return ret;
808 		data->enable_4GB = !!(val & F_DDR_4GB_SUPPORT_EN);
809 	}
810 
811 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
812 	data->base = devm_ioremap_resource(dev, res);
813 	if (IS_ERR(data->base))
814 		return PTR_ERR(data->base);
815 	ioaddr = res->start;
816 
817 	data->irq = platform_get_irq(pdev, 0);
818 	if (data->irq < 0)
819 		return data->irq;
820 
821 	if (MTK_IOMMU_HAS_FLAG(data->plat_data, HAS_BCLK)) {
822 		data->bclk = devm_clk_get(dev, "bclk");
823 		if (IS_ERR(data->bclk))
824 			return PTR_ERR(data->bclk);
825 	}
826 
827 	larb_nr = of_count_phandle_with_args(dev->of_node,
828 					     "mediatek,larbs", NULL);
829 	if (larb_nr < 0)
830 		return larb_nr;
831 
832 	for (i = 0; i < larb_nr; i++) {
833 		u32 id;
834 
835 		larbnode = of_parse_phandle(dev->of_node, "mediatek,larbs", i);
836 		if (!larbnode)
837 			return -EINVAL;
838 
839 		if (!of_device_is_available(larbnode)) {
840 			of_node_put(larbnode);
841 			continue;
842 		}
843 
844 		ret = of_property_read_u32(larbnode, "mediatek,larb-id", &id);
845 		if (ret)/* The id is consecutive if there is no this property */
846 			id = i;
847 
848 		plarbdev = of_find_device_by_node(larbnode);
849 		if (!plarbdev) {
850 			of_node_put(larbnode);
851 			return -EPROBE_DEFER;
852 		}
853 		data->larb_imu[id].dev = &plarbdev->dev;
854 
855 		component_match_add_release(dev, &match, release_of,
856 					    compare_of, larbnode);
857 	}
858 
859 	/* Get smi-common dev from the last larb. */
860 	smicomm_node = of_parse_phandle(larbnode, "mediatek,smi", 0);
861 	if (!smicomm_node)
862 		return -EINVAL;
863 
864 	plarbdev = of_find_device_by_node(smicomm_node);
865 	of_node_put(smicomm_node);
866 	data->smicomm_dev = &plarbdev->dev;
867 
868 	pm_runtime_enable(dev);
869 
870 	link = device_link_add(data->smicomm_dev, dev,
871 			DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME);
872 	if (!link) {
873 		dev_err(dev, "Unable to link %s.\n", dev_name(data->smicomm_dev));
874 		ret = -EINVAL;
875 		goto out_runtime_disable;
876 	}
877 
878 	platform_set_drvdata(pdev, data);
879 
880 	ret = iommu_device_sysfs_add(&data->iommu, dev, NULL,
881 				     "mtk-iommu.%pa", &ioaddr);
882 	if (ret)
883 		goto out_link_remove;
884 
885 	ret = iommu_device_register(&data->iommu, &mtk_iommu_ops, dev);
886 	if (ret)
887 		goto out_sysfs_remove;
888 
889 	spin_lock_init(&data->tlb_lock);
890 	list_add_tail(&data->list, &m4ulist);
891 
892 	if (!iommu_present(&platform_bus_type)) {
893 		ret = bus_set_iommu(&platform_bus_type, &mtk_iommu_ops);
894 		if (ret)
895 			goto out_list_del;
896 	}
897 
898 	ret = component_master_add_with_match(dev, &mtk_iommu_com_ops, match);
899 	if (ret)
900 		goto out_bus_set_null;
901 	return ret;
902 
903 out_bus_set_null:
904 	bus_set_iommu(&platform_bus_type, NULL);
905 out_list_del:
906 	list_del(&data->list);
907 	iommu_device_unregister(&data->iommu);
908 out_sysfs_remove:
909 	iommu_device_sysfs_remove(&data->iommu);
910 out_link_remove:
911 	device_link_remove(data->smicomm_dev, dev);
912 out_runtime_disable:
913 	pm_runtime_disable(dev);
914 	return ret;
915 }
916 
917 static int mtk_iommu_remove(struct platform_device *pdev)
918 {
919 	struct mtk_iommu_data *data = platform_get_drvdata(pdev);
920 
921 	iommu_device_sysfs_remove(&data->iommu);
922 	iommu_device_unregister(&data->iommu);
923 
924 	if (iommu_present(&platform_bus_type))
925 		bus_set_iommu(&platform_bus_type, NULL);
926 
927 	clk_disable_unprepare(data->bclk);
928 	device_link_remove(data->smicomm_dev, &pdev->dev);
929 	pm_runtime_disable(&pdev->dev);
930 	devm_free_irq(&pdev->dev, data->irq, data);
931 	component_master_del(&pdev->dev, &mtk_iommu_com_ops);
932 	return 0;
933 }
934 
935 static int __maybe_unused mtk_iommu_runtime_suspend(struct device *dev)
936 {
937 	struct mtk_iommu_data *data = dev_get_drvdata(dev);
938 	struct mtk_iommu_suspend_reg *reg = &data->reg;
939 	void __iomem *base = data->base;
940 
941 	reg->wr_len_ctrl = readl_relaxed(base + REG_MMU_WR_LEN_CTRL);
942 	reg->misc_ctrl = readl_relaxed(base + REG_MMU_MISC_CTRL);
943 	reg->dcm_dis = readl_relaxed(base + REG_MMU_DCM_DIS);
944 	reg->ctrl_reg = readl_relaxed(base + REG_MMU_CTRL_REG);
945 	reg->int_control0 = readl_relaxed(base + REG_MMU_INT_CONTROL0);
946 	reg->int_main_control = readl_relaxed(base + REG_MMU_INT_MAIN_CONTROL);
947 	reg->ivrp_paddr = readl_relaxed(base + REG_MMU_IVRP_PADDR);
948 	reg->vld_pa_rng = readl_relaxed(base + REG_MMU_VLD_PA_RNG);
949 	clk_disable_unprepare(data->bclk);
950 	return 0;
951 }
952 
953 static int __maybe_unused mtk_iommu_runtime_resume(struct device *dev)
954 {
955 	struct mtk_iommu_data *data = dev_get_drvdata(dev);
956 	struct mtk_iommu_suspend_reg *reg = &data->reg;
957 	struct mtk_iommu_domain *m4u_dom = data->m4u_dom;
958 	void __iomem *base = data->base;
959 	int ret;
960 
961 	ret = clk_prepare_enable(data->bclk);
962 	if (ret) {
963 		dev_err(data->dev, "Failed to enable clk(%d) in resume\n", ret);
964 		return ret;
965 	}
966 
967 	/*
968 	 * Uppon first resume, only enable the clk and return, since the values of the
969 	 * registers are not yet set.
970 	 */
971 	if (!m4u_dom)
972 		return 0;
973 
974 	writel_relaxed(reg->wr_len_ctrl, base + REG_MMU_WR_LEN_CTRL);
975 	writel_relaxed(reg->misc_ctrl, base + REG_MMU_MISC_CTRL);
976 	writel_relaxed(reg->dcm_dis, base + REG_MMU_DCM_DIS);
977 	writel_relaxed(reg->ctrl_reg, base + REG_MMU_CTRL_REG);
978 	writel_relaxed(reg->int_control0, base + REG_MMU_INT_CONTROL0);
979 	writel_relaxed(reg->int_main_control, base + REG_MMU_INT_MAIN_CONTROL);
980 	writel_relaxed(reg->ivrp_paddr, base + REG_MMU_IVRP_PADDR);
981 	writel_relaxed(reg->vld_pa_rng, base + REG_MMU_VLD_PA_RNG);
982 	writel(m4u_dom->cfg.arm_v7s_cfg.ttbr & MMU_PT_ADDR_MASK, base + REG_MMU_PT_BASE_ADDR);
983 	return 0;
984 }
985 
986 static const struct dev_pm_ops mtk_iommu_pm_ops = {
987 	SET_RUNTIME_PM_OPS(mtk_iommu_runtime_suspend, mtk_iommu_runtime_resume, NULL)
988 	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
989 				     pm_runtime_force_resume)
990 };
991 
992 static const struct mtk_iommu_plat_data mt2712_data = {
993 	.m4u_plat     = M4U_MT2712,
994 	.flags        = HAS_4GB_MODE | HAS_BCLK | HAS_VLD_PA_RNG,
995 	.inv_sel_reg  = REG_MMU_INV_SEL_GEN1,
996 	.iova_region  = single_domain,
997 	.iova_region_nr = ARRAY_SIZE(single_domain),
998 	.larbid_remap = {{0}, {1}, {2}, {3}, {4}, {5}, {6}, {7}},
999 };
1000 
1001 static const struct mtk_iommu_plat_data mt6779_data = {
1002 	.m4u_plat      = M4U_MT6779,
1003 	.flags         = HAS_SUB_COMM | OUT_ORDER_WR_EN | WR_THROT_EN,
1004 	.inv_sel_reg   = REG_MMU_INV_SEL_GEN2,
1005 	.iova_region   = single_domain,
1006 	.iova_region_nr = ARRAY_SIZE(single_domain),
1007 	.larbid_remap  = {{0}, {1}, {2}, {3}, {5}, {7, 8}, {10}, {9}},
1008 };
1009 
1010 static const struct mtk_iommu_plat_data mt8167_data = {
1011 	.m4u_plat     = M4U_MT8167,
1012 	.flags        = RESET_AXI | HAS_LEGACY_IVRP_PADDR,
1013 	.inv_sel_reg  = REG_MMU_INV_SEL_GEN1,
1014 	.iova_region  = single_domain,
1015 	.iova_region_nr = ARRAY_SIZE(single_domain),
1016 	.larbid_remap = {{0}, {1}, {2}}, /* Linear mapping. */
1017 };
1018 
1019 static const struct mtk_iommu_plat_data mt8173_data = {
1020 	.m4u_plat     = M4U_MT8173,
1021 	.flags	      = HAS_4GB_MODE | HAS_BCLK | RESET_AXI |
1022 			HAS_LEGACY_IVRP_PADDR,
1023 	.inv_sel_reg  = REG_MMU_INV_SEL_GEN1,
1024 	.iova_region  = single_domain,
1025 	.iova_region_nr = ARRAY_SIZE(single_domain),
1026 	.larbid_remap = {{0}, {1}, {2}, {3}, {4}, {5}}, /* Linear mapping. */
1027 };
1028 
1029 static const struct mtk_iommu_plat_data mt8183_data = {
1030 	.m4u_plat     = M4U_MT8183,
1031 	.flags        = RESET_AXI,
1032 	.inv_sel_reg  = REG_MMU_INV_SEL_GEN1,
1033 	.iova_region  = single_domain,
1034 	.iova_region_nr = ARRAY_SIZE(single_domain),
1035 	.larbid_remap = {{0}, {4}, {5}, {6}, {7}, {2}, {3}, {1}},
1036 };
1037 
1038 static const struct mtk_iommu_plat_data mt8192_data = {
1039 	.m4u_plat       = M4U_MT8192,
1040 	.flags          = HAS_BCLK | HAS_SUB_COMM | OUT_ORDER_WR_EN |
1041 			  WR_THROT_EN | IOVA_34_EN,
1042 	.inv_sel_reg    = REG_MMU_INV_SEL_GEN2,
1043 	.iova_region    = mt8192_multi_dom,
1044 	.iova_region_nr = ARRAY_SIZE(mt8192_multi_dom),
1045 	.larbid_remap   = {{0}, {1}, {4, 5}, {7}, {2}, {9, 11, 19, 20},
1046 			   {0, 14, 16}, {0, 13, 18, 17}},
1047 };
1048 
1049 static const struct of_device_id mtk_iommu_of_ids[] = {
1050 	{ .compatible = "mediatek,mt2712-m4u", .data = &mt2712_data},
1051 	{ .compatible = "mediatek,mt6779-m4u", .data = &mt6779_data},
1052 	{ .compatible = "mediatek,mt8167-m4u", .data = &mt8167_data},
1053 	{ .compatible = "mediatek,mt8173-m4u", .data = &mt8173_data},
1054 	{ .compatible = "mediatek,mt8183-m4u", .data = &mt8183_data},
1055 	{ .compatible = "mediatek,mt8192-m4u", .data = &mt8192_data},
1056 	{}
1057 };
1058 
1059 static struct platform_driver mtk_iommu_driver = {
1060 	.probe	= mtk_iommu_probe,
1061 	.remove	= mtk_iommu_remove,
1062 	.driver	= {
1063 		.name = "mtk-iommu",
1064 		.of_match_table = mtk_iommu_of_ids,
1065 		.pm = &mtk_iommu_pm_ops,
1066 	}
1067 };
1068 module_platform_driver(mtk_iommu_driver);
1069 
1070 MODULE_DESCRIPTION("IOMMU API for MediaTek M4U implementations");
1071 MODULE_LICENSE("GPL v2");
1072