xref: /openbmc/linux/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c (revision a242f4297cfe3f4589a7620dcd42cc503607fc6b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2019, The Linux Foundation. All rights reserved.
4  */
5 
6 #include <linux/acpi.h>
7 #include <linux/adreno-smmu-priv.h>
8 #include <linux/of_device.h>
9 #include <linux/qcom_scm.h>
10 
11 #include "arm-smmu.h"
12 
13 struct qcom_smmu {
14 	struct arm_smmu_device smmu;
15 	bool bypass_quirk;
16 	u8 bypass_cbndx;
17 };
18 
19 static struct qcom_smmu *to_qcom_smmu(struct arm_smmu_device *smmu)
20 {
21 	return container_of(smmu, struct qcom_smmu, smmu);
22 }
23 
24 static void qcom_adreno_smmu_write_sctlr(struct arm_smmu_device *smmu, int idx,
25 		u32 reg)
26 {
27 	/*
28 	 * On the GPU device we want to process subsequent transactions after a
29 	 * fault to keep the GPU from hanging
30 	 */
31 	reg |= ARM_SMMU_SCTLR_HUPCF;
32 
33 	arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_SCTLR, reg);
34 }
35 
36 #define QCOM_ADRENO_SMMU_GPU_SID 0
37 
38 static bool qcom_adreno_smmu_is_gpu_device(struct device *dev)
39 {
40 	struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
41 	int i;
42 
43 	/*
44 	 * The GPU will always use SID 0 so that is a handy way to uniquely
45 	 * identify it and configure it for per-instance pagetables
46 	 */
47 	for (i = 0; i < fwspec->num_ids; i++) {
48 		u16 sid = FIELD_GET(ARM_SMMU_SMR_ID, fwspec->ids[i]);
49 
50 		if (sid == QCOM_ADRENO_SMMU_GPU_SID)
51 			return true;
52 	}
53 
54 	return false;
55 }
56 
57 static const struct io_pgtable_cfg *qcom_adreno_smmu_get_ttbr1_cfg(
58 		const void *cookie)
59 {
60 	struct arm_smmu_domain *smmu_domain = (void *)cookie;
61 	struct io_pgtable *pgtable =
62 		io_pgtable_ops_to_pgtable(smmu_domain->pgtbl_ops);
63 	return &pgtable->cfg;
64 }
65 
66 /*
67  * Local implementation to configure TTBR0 with the specified pagetable config.
68  * The GPU driver will call this to enable TTBR0 when per-instance pagetables
69  * are active
70  */
71 
72 static int qcom_adreno_smmu_set_ttbr0_cfg(const void *cookie,
73 		const struct io_pgtable_cfg *pgtbl_cfg)
74 {
75 	struct arm_smmu_domain *smmu_domain = (void *)cookie;
76 	struct io_pgtable *pgtable = io_pgtable_ops_to_pgtable(smmu_domain->pgtbl_ops);
77 	struct arm_smmu_cfg *cfg = &smmu_domain->cfg;
78 	struct arm_smmu_cb *cb = &smmu_domain->smmu->cbs[cfg->cbndx];
79 
80 	/* The domain must have split pagetables already enabled */
81 	if (cb->tcr[0] & ARM_SMMU_TCR_EPD1)
82 		return -EINVAL;
83 
84 	/* If the pagetable config is NULL, disable TTBR0 */
85 	if (!pgtbl_cfg) {
86 		/* Do nothing if it is already disabled */
87 		if ((cb->tcr[0] & ARM_SMMU_TCR_EPD0))
88 			return -EINVAL;
89 
90 		/* Set TCR to the original configuration */
91 		cb->tcr[0] = arm_smmu_lpae_tcr(&pgtable->cfg);
92 		cb->ttbr[0] = FIELD_PREP(ARM_SMMU_TTBRn_ASID, cb->cfg->asid);
93 	} else {
94 		u32 tcr = cb->tcr[0];
95 
96 		/* Don't call this again if TTBR0 is already enabled */
97 		if (!(cb->tcr[0] & ARM_SMMU_TCR_EPD0))
98 			return -EINVAL;
99 
100 		tcr |= arm_smmu_lpae_tcr(pgtbl_cfg);
101 		tcr &= ~(ARM_SMMU_TCR_EPD0 | ARM_SMMU_TCR_EPD1);
102 
103 		cb->tcr[0] = tcr;
104 		cb->ttbr[0] = pgtbl_cfg->arm_lpae_s1_cfg.ttbr;
105 		cb->ttbr[0] |= FIELD_PREP(ARM_SMMU_TTBRn_ASID, cb->cfg->asid);
106 	}
107 
108 	arm_smmu_write_context_bank(smmu_domain->smmu, cb->cfg->cbndx);
109 
110 	return 0;
111 }
112 
113 static int qcom_adreno_smmu_alloc_context_bank(struct arm_smmu_domain *smmu_domain,
114 					       struct arm_smmu_device *smmu,
115 					       struct device *dev, int start)
116 {
117 	int count;
118 
119 	/*
120 	 * Assign context bank 0 to the GPU device so the GPU hardware can
121 	 * switch pagetables
122 	 */
123 	if (qcom_adreno_smmu_is_gpu_device(dev)) {
124 		start = 0;
125 		count = 1;
126 	} else {
127 		start = 1;
128 		count = smmu->num_context_banks;
129 	}
130 
131 	return __arm_smmu_alloc_bitmap(smmu->context_map, start, count);
132 }
133 
134 static bool qcom_adreno_can_do_ttbr1(struct arm_smmu_device *smmu)
135 {
136 	const struct device_node *np = smmu->dev->of_node;
137 
138 	if (of_device_is_compatible(np, "qcom,msm8996-smmu-v2"))
139 		return false;
140 
141 	return true;
142 }
143 
144 static int qcom_adreno_smmu_init_context(struct arm_smmu_domain *smmu_domain,
145 		struct io_pgtable_cfg *pgtbl_cfg, struct device *dev)
146 {
147 	struct adreno_smmu_priv *priv;
148 
149 	/* Only enable split pagetables for the GPU device (SID 0) */
150 	if (!qcom_adreno_smmu_is_gpu_device(dev))
151 		return 0;
152 
153 	/*
154 	 * All targets that use the qcom,adreno-smmu compatible string *should*
155 	 * be AARCH64 stage 1 but double check because the arm-smmu code assumes
156 	 * that is the case when the TTBR1 quirk is enabled
157 	 */
158 	if (qcom_adreno_can_do_ttbr1(smmu_domain->smmu) &&
159 	    (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) &&
160 	    (smmu_domain->cfg.fmt == ARM_SMMU_CTX_FMT_AARCH64))
161 		pgtbl_cfg->quirks |= IO_PGTABLE_QUIRK_ARM_TTBR1;
162 
163 	/*
164 	 * Initialize private interface with GPU:
165 	 */
166 
167 	priv = dev_get_drvdata(dev);
168 	priv->cookie = smmu_domain;
169 	priv->get_ttbr1_cfg = qcom_adreno_smmu_get_ttbr1_cfg;
170 	priv->set_ttbr0_cfg = qcom_adreno_smmu_set_ttbr0_cfg;
171 
172 	return 0;
173 }
174 
175 static const struct of_device_id qcom_smmu_client_of_match[] __maybe_unused = {
176 	{ .compatible = "qcom,adreno" },
177 	{ .compatible = "qcom,mdp4" },
178 	{ .compatible = "qcom,mdss" },
179 	{ .compatible = "qcom,sc7180-mdss" },
180 	{ .compatible = "qcom,sc7180-mss-pil" },
181 	{ .compatible = "qcom,sc8180x-mdss" },
182 	{ .compatible = "qcom,sdm845-mdss" },
183 	{ .compatible = "qcom,sdm845-mss-pil" },
184 	{ }
185 };
186 
187 static int qcom_smmu_cfg_probe(struct arm_smmu_device *smmu)
188 {
189 	unsigned int last_s2cr = ARM_SMMU_GR0_S2CR(smmu->num_mapping_groups - 1);
190 	struct qcom_smmu *qsmmu = to_qcom_smmu(smmu);
191 	u32 reg;
192 	u32 smr;
193 	int i;
194 
195 	/*
196 	 * With some firmware versions writes to S2CR of type FAULT are
197 	 * ignored, and writing BYPASS will end up written as FAULT in the
198 	 * register. Perform a write to S2CR to detect if this is the case and
199 	 * if so reserve a context bank to emulate bypass streams.
200 	 */
201 	reg = FIELD_PREP(ARM_SMMU_S2CR_TYPE, S2CR_TYPE_BYPASS) |
202 	      FIELD_PREP(ARM_SMMU_S2CR_CBNDX, 0xff) |
203 	      FIELD_PREP(ARM_SMMU_S2CR_PRIVCFG, S2CR_PRIVCFG_DEFAULT);
204 	arm_smmu_gr0_write(smmu, last_s2cr, reg);
205 	reg = arm_smmu_gr0_read(smmu, last_s2cr);
206 	if (FIELD_GET(ARM_SMMU_S2CR_TYPE, reg) != S2CR_TYPE_BYPASS) {
207 		qsmmu->bypass_quirk = true;
208 		qsmmu->bypass_cbndx = smmu->num_context_banks - 1;
209 
210 		set_bit(qsmmu->bypass_cbndx, smmu->context_map);
211 
212 		arm_smmu_cb_write(smmu, qsmmu->bypass_cbndx, ARM_SMMU_CB_SCTLR, 0);
213 
214 		reg = FIELD_PREP(ARM_SMMU_CBAR_TYPE, CBAR_TYPE_S1_TRANS_S2_BYPASS);
215 		arm_smmu_gr1_write(smmu, ARM_SMMU_GR1_CBAR(qsmmu->bypass_cbndx), reg);
216 	}
217 
218 	for (i = 0; i < smmu->num_mapping_groups; i++) {
219 		smr = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_SMR(i));
220 
221 		if (FIELD_GET(ARM_SMMU_SMR_VALID, smr)) {
222 			/* Ignore valid bit for SMR mask extraction. */
223 			smr &= ~ARM_SMMU_SMR_VALID;
224 			smmu->smrs[i].id = FIELD_GET(ARM_SMMU_SMR_ID, smr);
225 			smmu->smrs[i].mask = FIELD_GET(ARM_SMMU_SMR_MASK, smr);
226 			smmu->smrs[i].valid = true;
227 
228 			smmu->s2crs[i].type = S2CR_TYPE_BYPASS;
229 			smmu->s2crs[i].privcfg = S2CR_PRIVCFG_DEFAULT;
230 			smmu->s2crs[i].cbndx = 0xff;
231 		}
232 	}
233 
234 	return 0;
235 }
236 
237 static void qcom_smmu_write_s2cr(struct arm_smmu_device *smmu, int idx)
238 {
239 	struct arm_smmu_s2cr *s2cr = smmu->s2crs + idx;
240 	struct qcom_smmu *qsmmu = to_qcom_smmu(smmu);
241 	u32 cbndx = s2cr->cbndx;
242 	u32 type = s2cr->type;
243 	u32 reg;
244 
245 	if (qsmmu->bypass_quirk) {
246 		if (type == S2CR_TYPE_BYPASS) {
247 			/*
248 			 * Firmware with quirky S2CR handling will substitute
249 			 * BYPASS writes with FAULT, so point the stream to the
250 			 * reserved context bank and ask for translation on the
251 			 * stream
252 			 */
253 			type = S2CR_TYPE_TRANS;
254 			cbndx = qsmmu->bypass_cbndx;
255 		} else if (type == S2CR_TYPE_FAULT) {
256 			/*
257 			 * Firmware with quirky S2CR handling will ignore FAULT
258 			 * writes, so trick it to write FAULT by asking for a
259 			 * BYPASS.
260 			 */
261 			type = S2CR_TYPE_BYPASS;
262 			cbndx = 0xff;
263 		}
264 	}
265 
266 	reg = FIELD_PREP(ARM_SMMU_S2CR_TYPE, type) |
267 	      FIELD_PREP(ARM_SMMU_S2CR_CBNDX, cbndx) |
268 	      FIELD_PREP(ARM_SMMU_S2CR_PRIVCFG, s2cr->privcfg);
269 	arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_S2CR(idx), reg);
270 }
271 
272 static int qcom_smmu_def_domain_type(struct device *dev)
273 {
274 	const struct of_device_id *match =
275 		of_match_device(qcom_smmu_client_of_match, dev);
276 
277 	return match ? IOMMU_DOMAIN_IDENTITY : 0;
278 }
279 
280 static int qcom_sdm845_smmu500_reset(struct arm_smmu_device *smmu)
281 {
282 	int ret;
283 
284 	/*
285 	 * To address performance degradation in non-real time clients,
286 	 * such as USB and UFS, turn off wait-for-safe on sdm845 based boards,
287 	 * such as MTP and db845, whose firmwares implement secure monitor
288 	 * call handlers to turn on/off the wait-for-safe logic.
289 	 */
290 	ret = qcom_scm_qsmmu500_wait_safe_toggle(0);
291 	if (ret)
292 		dev_warn(smmu->dev, "Failed to turn off SAFE logic\n");
293 
294 	return ret;
295 }
296 
297 static int qcom_smmu500_reset(struct arm_smmu_device *smmu)
298 {
299 	const struct device_node *np = smmu->dev->of_node;
300 
301 	arm_mmu500_reset(smmu);
302 
303 	if (of_device_is_compatible(np, "qcom,sdm845-smmu-500"))
304 		return qcom_sdm845_smmu500_reset(smmu);
305 
306 	return 0;
307 }
308 
309 static const struct arm_smmu_impl qcom_smmu_impl = {
310 	.cfg_probe = qcom_smmu_cfg_probe,
311 	.def_domain_type = qcom_smmu_def_domain_type,
312 	.reset = qcom_smmu500_reset,
313 	.write_s2cr = qcom_smmu_write_s2cr,
314 };
315 
316 static const struct arm_smmu_impl qcom_adreno_smmu_impl = {
317 	.init_context = qcom_adreno_smmu_init_context,
318 	.def_domain_type = qcom_smmu_def_domain_type,
319 	.reset = qcom_smmu500_reset,
320 	.alloc_context_bank = qcom_adreno_smmu_alloc_context_bank,
321 	.write_sctlr = qcom_adreno_smmu_write_sctlr,
322 };
323 
324 static struct arm_smmu_device *qcom_smmu_create(struct arm_smmu_device *smmu,
325 		const struct arm_smmu_impl *impl)
326 {
327 	struct qcom_smmu *qsmmu;
328 
329 	/* Check to make sure qcom_scm has finished probing */
330 	if (!qcom_scm_is_available())
331 		return ERR_PTR(-EPROBE_DEFER);
332 
333 	qsmmu = devm_krealloc(smmu->dev, smmu, sizeof(*qsmmu), GFP_KERNEL);
334 	if (!qsmmu)
335 		return ERR_PTR(-ENOMEM);
336 
337 	qsmmu->smmu.impl = impl;
338 
339 	return &qsmmu->smmu;
340 }
341 
342 static const struct of_device_id __maybe_unused qcom_smmu_impl_of_match[] = {
343 	{ .compatible = "qcom,msm8998-smmu-v2" },
344 	{ .compatible = "qcom,sc7180-smmu-500" },
345 	{ .compatible = "qcom,sc8180x-smmu-500" },
346 	{ .compatible = "qcom,sdm630-smmu-v2" },
347 	{ .compatible = "qcom,sdm845-smmu-500" },
348 	{ .compatible = "qcom,sm6125-smmu-500" },
349 	{ .compatible = "qcom,sm8150-smmu-500" },
350 	{ .compatible = "qcom,sm8250-smmu-500" },
351 	{ .compatible = "qcom,sm8350-smmu-500" },
352 	{ }
353 };
354 
355 static struct acpi_platform_list qcom_acpi_platlist[] = {
356 	{ "LENOVO", "CB-01   ", 0x8180, ACPI_SIG_IORT, equal, "QCOM SMMU" },
357 	{ "QCOM  ", "QCOMEDK2", 0x8180, ACPI_SIG_IORT, equal, "QCOM SMMU" },
358 	{ }
359 };
360 
361 struct arm_smmu_device *qcom_smmu_impl_init(struct arm_smmu_device *smmu)
362 {
363 	const struct device_node *np = smmu->dev->of_node;
364 
365 	if (np == NULL) {
366 		/* Match platform for ACPI boot */
367 		if (acpi_match_platform_list(qcom_acpi_platlist) >= 0)
368 			return qcom_smmu_create(smmu, &qcom_smmu_impl);
369 	}
370 
371 	if (of_match_node(qcom_smmu_impl_of_match, np))
372 		return qcom_smmu_create(smmu, &qcom_smmu_impl);
373 
374 	if (of_device_is_compatible(np, "qcom,adreno-smmu"))
375 		return qcom_smmu_create(smmu, &qcom_adreno_smmu_impl);
376 
377 	return smmu;
378 }
379