1 /*
2  * Copyright (c) 2017-2022, 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 /*
73  * Initialize the SMMU by invalidating all secure caches and TLBs.
74  * Abort all incoming transactions in order to implement a default
75  * deny policy on reset
76  */
smmuv3_init(uintptr_t smmu_base)77 int __init smmuv3_init(uintptr_t smmu_base)
78 {
79 	/* Abort all incoming transactions */
80 	if (smmuv3_security_init(smmu_base) != 0)
81 		return -1;
82 
83 #if ENABLE_RME
84 
85 	if (get_armv9_2_feat_rme_support() != 0U) {
86 		if ((mmio_read_32(smmu_base + SMMU_ROOT_IDR0) &
87 				  SMMU_ROOT_IDR0_ROOT_IMPL) == 0U) {
88 			WARN("Skip SMMU GPC configuration.\n");
89 		} else {
90 			uint64_t gpccr_el3 = read_gpccr_el3();
91 			uint64_t gptbr_el3 = read_gptbr_el3();
92 
93 			/* SMMU_ROOT_GPT_BASE_CFG[16] is RES0. */
94 			gpccr_el3 &= ~(1UL << 16);
95 
96 			/*
97 			 * TODO: SMMU_ROOT_GPT_BASE_CFG is 64b in the spec,
98 			 * but SMMU model only accepts 32b access.
99 			 */
100 			mmio_write_32(smmu_base + SMMU_ROOT_GPT_BASE_CFG,
101 				      gpccr_el3);
102 
103 			/*
104 			 * pa_gpt_table_base[51:12] maps to GPTBR_EL3[39:0]
105 			 * whereas it maps to SMMU_ROOT_GPT_BASE[51:12]
106 			 * hence needs a 12 bit left shit.
107 			 */
108 			mmio_write_64(smmu_base + SMMU_ROOT_GPT_BASE,
109 				      gptbr_el3 << 12);
110 
111 			/*
112 			 * ACCESSEN=1: SMMU- and client-originated accesses are
113 			 *             not terminated by this mechanism.
114 			 * GPCEN=1: All clients and SMMU-originated accesses,
115 			 *          except GPT-walks, are subject to GPC.
116 			 */
117 			mmio_setbits_32(smmu_base + SMMU_ROOT_CR0,
118 					SMMU_ROOT_CR0_GPCEN |
119 					SMMU_ROOT_CR0_ACCESSEN);
120 
121 			/* Poll for ACCESSEN and GPCEN ack bits. */
122 			if (smmuv3_poll(smmu_base + SMMU_ROOT_CR0ACK,
123 					SMMU_ROOT_CR0_GPCEN |
124 					SMMU_ROOT_CR0_ACCESSEN,
125 					SMMU_ROOT_CR0_GPCEN |
126 					SMMU_ROOT_CR0_ACCESSEN) != 0) {
127 				WARN("Failed enabling SMMU GPC.\n");
128 
129 				/*
130 				 * Do not return in error, but fall back to
131 				 * invalidating all entries through the secure
132 				 * register file.
133 				 */
134 			}
135 		}
136 	}
137 
138 #endif /* ENABLE_RME */
139 
140 	/*
141 	 * Initiate invalidation of secure caches and TLBs if the SMMU
142 	 * supports secure state. If not, it's implementation defined
143 	 * as to how SMMU_S_INIT register is accessed.
144 	 * Arm SMMU Arch RME supplement, section 3.4: all SMMU registers
145 	 * specified to be accessible only in secure physical address space are
146 	 * additionally accessible in root physical address space in an SMMU
147 	 * with RME.
148 	 * Section 3.3: as GPT information is permitted to be cached in a TLB,
149 	 * the SMMU_S_INIT.INV_ALL mechanism also invalidates GPT information
150 	 * cached in TLBs.
151 	 */
152 	mmio_write_32(smmu_base + SMMU_S_INIT, SMMU_S_INIT_INV_ALL);
153 
154 	/* Wait for global invalidation operation to finish */
155 	return smmuv3_poll(smmu_base + SMMU_S_INIT,
156 				SMMU_S_INIT_INV_ALL, 0U);
157 }
158 
smmuv3_ns_set_abort_all(uintptr_t smmu_base)159 int smmuv3_ns_set_abort_all(uintptr_t smmu_base)
160 {
161 	/* Attribute update has completed when SMMU_GBPA.Update bit is 0 */
162 	if (smmuv3_poll(smmu_base + SMMU_GBPA, SMMU_GBPA_UPDATE, 0U) != 0U) {
163 		return -1;
164 	}
165 
166 	/*
167 	 * Set GBPA's ABORT bit. Other GBPA fields are presumably ignored then,
168 	 * so simply preserve their value.
169 	 */
170 	mmio_setbits_32(smmu_base + SMMU_GBPA, SMMU_GBPA_UPDATE | SMMU_GBPA_ABORT);
171 	if (smmuv3_poll(smmu_base + SMMU_GBPA, SMMU_GBPA_UPDATE, 0U) != 0U) {
172 		return -1;
173 	}
174 
175 	/* Disable the SMMU to engage the GBPA fields previously configured. */
176 	mmio_clrbits_32(smmu_base + SMMU_CR0, SMMU_CR0_SMMUEN);
177 	if (smmuv3_poll(smmu_base + SMMU_CR0ACK, SMMU_CR0_SMMUEN, 0U) != 0U) {
178 		return -1;
179 	}
180 
181 	return 0;
182 }
183