1 /*
2  * Copyright (c) 2017-2024, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <common/debug.h>
8 #include <cdefs.h>
9 #include <drivers/arm/smmu_v3.h>
10 #include <drivers/delay_timer.h>
11 #include <lib/mmio.h>
12 #include <arch_features.h>
13 
14 /* SMMU poll number of retries */
15 #define SMMU_POLL_TIMEOUT_US	U(1000)
16 
smmuv3_poll(uintptr_t smmu_reg,uint32_t mask,uint32_t value)17 static int smmuv3_poll(uintptr_t smmu_reg, uint32_t mask,
18 				uint32_t value)
19 {
20 	uint32_t reg_val;
21 	uint64_t timeout;
22 
23 	/* Set 1ms timeout value */
24 	timeout = timeout_init_us(SMMU_POLL_TIMEOUT_US);
25 	do {
26 		reg_val = mmio_read_32(smmu_reg);
27 		if ((reg_val & mask) == value)
28 			return 0;
29 	} while (!timeout_elapsed(timeout));
30 
31 	ERROR("Timeout polling SMMUv3 register @%p\n", (void *)smmu_reg);
32 	ERROR("Read value 0x%x, expected 0x%x\n", reg_val,
33 		value == 0U ? reg_val & ~mask : reg_val | mask);
34 	return -1;
35 }
36 
37 /*
38  * Abort all incoming transactions in order to implement a default
39  * deny policy on reset.
40  */
smmuv3_security_init(uintptr_t smmu_base)41 int __init smmuv3_security_init(uintptr_t smmu_base)
42 {
43 	/* Attribute update has completed when SMMU_(S)_GBPA.Update bit is 0 */
44 	if (smmuv3_poll(smmu_base + SMMU_GBPA, SMMU_GBPA_UPDATE, 0U) != 0U)
45 		return -1;
46 
47 	/*
48 	 * SMMU_(S)_CR0 resets to zero with all streams bypassing the SMMU,
49 	 * so just abort all incoming transactions.
50 	 */
51 	mmio_setbits_32(smmu_base + SMMU_GBPA,
52 			SMMU_GBPA_UPDATE | SMMU_GBPA_ABORT);
53 
54 	if (smmuv3_poll(smmu_base + SMMU_GBPA, SMMU_GBPA_UPDATE, 0U) != 0U)
55 		return -1;
56 
57 	/* Check if the SMMU supports secure state */
58 	if ((mmio_read_32(smmu_base + SMMU_S_IDR1) &
59 				SMMU_S_IDR1_SECURE_IMPL) == 0U)
60 		return 0;
61 
62 	/* Abort all incoming secure transactions */
63 	if (smmuv3_poll(smmu_base + SMMU_S_GBPA, SMMU_S_GBPA_UPDATE, 0U) != 0U)
64 		return -1;
65 
66 	mmio_setbits_32(smmu_base + SMMU_S_GBPA,
67 			SMMU_S_GBPA_UPDATE | SMMU_S_GBPA_ABORT);
68 
69 	return smmuv3_poll(smmu_base + SMMU_S_GBPA, SMMU_S_GBPA_UPDATE, 0U);
70 }
71 
72 /* Initialize the SMMU by invalidating all secure caches and TLBs. */
smmuv3_init(uintptr_t smmu_base)73 int __init smmuv3_init(uintptr_t smmu_base)
74 {
75 	/*
76 	 * Initiate invalidation of secure caches and TLBs if the SMMU
77 	 * supports secure state. If not, it's implementation defined
78 	 * as to how SMMU_S_INIT register is accessed.
79 	 * As per Arm SMMUv3 specification the SMMU_S_INIT register in a SMMU
80 	 * with RME implementation has following properties:
81 	 * a) all SMMU registers that are specified to be accessible only in
82 	 *    the Secure physical address space are additionally accessible in
83 	 *    Root physical address space.
84 	 * b) as GPT information is permitted to be cached in a TLB, the
85 	 *    SMMU_S_INIT.INV_ALL operation also invalidates all GPT information
86 	 *    cached in TLBs.
87 	 * Additionally, it is Root firmware’s responsibility to write to
88 	 * INV_ALL before enabling SMMU_ROOT_CR0.{ACCESSEN,GPCEN}.
89 	 */
90 	mmio_write_32(smmu_base + SMMU_S_INIT, SMMU_S_INIT_INV_ALL);
91 
92 	/* Wait for global invalidation operation to finish */
93 	if (smmuv3_poll(smmu_base + SMMU_S_INIT,
94 			SMMU_S_INIT_INV_ALL, 0U) != 0) {
95 		return -1;
96 	}
97 
98 #if ENABLE_RME
99 
100 	if (is_feat_rme_present()) {
101 		if ((mmio_read_32(smmu_base + SMMU_ROOT_IDR0) &
102 				  SMMU_ROOT_IDR0_ROOT_IMPL) == 0U) {
103 			WARN("Skip SMMU GPC configuration.\n");
104 		} else {
105 			uint64_t gpccr_el3 = read_gpccr_el3();
106 			uint64_t gptbr_el3 = read_gptbr_el3();
107 
108 			/* SMMU_ROOT_GPT_BASE_CFG[16] is RES0. */
109 			gpccr_el3 &= ~(1UL << 16);
110 
111 			/*
112 			 * TODO: SMMU_ROOT_GPT_BASE_CFG is 64b in the spec,
113 			 * but SMMU model only accepts 32b access.
114 			 */
115 			mmio_write_32(smmu_base + SMMU_ROOT_GPT_BASE_CFG,
116 				      gpccr_el3);
117 
118 			/*
119 			 * pa_gpt_table_base[51:12] maps to GPTBR_EL3[39:0]
120 			 * whereas it maps to SMMU_ROOT_GPT_BASE[51:12]
121 			 * hence needs a 12 bit left shit.
122 			 */
123 			mmio_write_64(smmu_base + SMMU_ROOT_GPT_BASE,
124 				      gptbr_el3 << 12);
125 
126 			/*
127 			 * ACCESSEN=1: SMMU- and client-originated accesses are
128 			 *             not terminated by this mechanism.
129 			 * GPCEN=1: All clients and SMMU-originated accesses,
130 			 *          except GPT-walks, are subject to GPC.
131 			 */
132 			mmio_setbits_32(smmu_base + SMMU_ROOT_CR0,
133 					SMMU_ROOT_CR0_GPCEN |
134 					SMMU_ROOT_CR0_ACCESSEN);
135 
136 			/* Poll for ACCESSEN and GPCEN ack bits. */
137 			if (smmuv3_poll(smmu_base + SMMU_ROOT_CR0ACK,
138 					SMMU_ROOT_CR0_GPCEN |
139 					SMMU_ROOT_CR0_ACCESSEN,
140 					SMMU_ROOT_CR0_GPCEN |
141 					SMMU_ROOT_CR0_ACCESSEN) != 0) {
142 				WARN("Failed enabling SMMU GPC.\n");
143 
144 				/*
145 				 * Do not return in error, but fall back to
146 				 * invalidating all entries through the secure
147 				 * register file.
148 				 */
149 			}
150 		}
151 	}
152 
153 #endif /* ENABLE_RME */
154 
155 	return 0;
156 }
157 
smmuv3_ns_set_abort_all(uintptr_t smmu_base)158 int smmuv3_ns_set_abort_all(uintptr_t smmu_base)
159 {
160 	/* Attribute update has completed when SMMU_GBPA.Update bit is 0 */
161 	if (smmuv3_poll(smmu_base + SMMU_GBPA, SMMU_GBPA_UPDATE, 0U) != 0U) {
162 		return -1;
163 	}
164 
165 	/*
166 	 * Set GBPA's ABORT bit. Other GBPA fields are presumably ignored then,
167 	 * so simply preserve their value.
168 	 */
169 	mmio_setbits_32(smmu_base + SMMU_GBPA, SMMU_GBPA_UPDATE | SMMU_GBPA_ABORT);
170 	if (smmuv3_poll(smmu_base + SMMU_GBPA, SMMU_GBPA_UPDATE, 0U) != 0U) {
171 		return -1;
172 	}
173 
174 	/* Disable the SMMU to engage the GBPA fields previously configured. */
175 	mmio_clrbits_32(smmu_base + SMMU_CR0, SMMU_CR0_SMMUEN);
176 	if (smmuv3_poll(smmu_base + SMMU_CR0ACK, SMMU_CR0_SMMUEN, 0U) != 0U) {
177 		return -1;
178 	}
179 
180 	return 0;
181 }
182