1 /*
2  * Copyright (c) 2017-2021, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <stdbool.h>
9 
10 #include <platform_def.h>
11 
12 #include <arch.h>
13 #include <arch_features.h>
14 #include <arch_helpers.h>
15 #include <lib/cassert.h>
16 #include <lib/utils_def.h>
17 #include <lib/xlat_tables/xlat_tables_v2.h>
18 
19 #include "../xlat_tables_private.h"
20 
21 #if (ARM_ARCH_MAJOR == 7) && !defined(ARMV7_SUPPORTS_LARGE_PAGE_ADDRESSING)
22 #error ARMv7 target does not support LPAE MMU descriptors
23 #endif
24 
25 /*
26  * Returns true if the provided granule size is supported, false otherwise.
27  */
xlat_arch_is_granule_size_supported(size_t size)28 bool xlat_arch_is_granule_size_supported(size_t size)
29 {
30 	/*
31 	 * The library uses the long descriptor translation table format, which
32 	 * supports 4 KiB pages only.
33 	 */
34 	return size == PAGE_SIZE_4KB;
35 }
36 
xlat_arch_get_max_supported_granule_size(void)37 size_t xlat_arch_get_max_supported_granule_size(void)
38 {
39 	return PAGE_SIZE_4KB;
40 }
41 
42 /*
43  * Determine the physical address space encoded in the 'attr' parameter.
44  *
45  * The physical address will fall into one of two spaces; secure or
46  * nonsecure.
47  */
xlat_arch_get_pas(uint32_t attr)48 uint32_t xlat_arch_get_pas(uint32_t attr)
49 {
50 	uint32_t pas = MT_PAS(attr);
51 
52 	if (pas == MT_NS) {
53 		return LOWER_ATTRS(NS);
54 	} else { /* MT_SECURE */
55 		return 0U;
56 	}
57 }
58 
59 #if ENABLE_ASSERTIONS
xlat_arch_get_max_supported_pa(void)60 unsigned long long xlat_arch_get_max_supported_pa(void)
61 {
62 	/* Physical address space size for long descriptor format. */
63 	return (1ULL << 40) - 1ULL;
64 }
65 
66 /*
67  * Return minimum virtual address space size supported by the architecture
68  */
xlat_get_min_virt_addr_space_size(void)69 uintptr_t xlat_get_min_virt_addr_space_size(void)
70 {
71 	return MIN_VIRT_ADDR_SPACE_SIZE;
72 }
73 #endif /* ENABLE_ASSERTIONS*/
74 
is_mmu_enabled_ctx(const xlat_ctx_t * ctx)75 bool is_mmu_enabled_ctx(const xlat_ctx_t *ctx)
76 {
77 	if (ctx->xlat_regime == EL1_EL0_REGIME) {
78 		assert(xlat_arch_current_el() == 1U);
79 		return (read_sctlr() & SCTLR_M_BIT) != 0U;
80 	} else {
81 		assert(ctx->xlat_regime == EL2_REGIME);
82 		assert(xlat_arch_current_el() == 2U);
83 		return (read_hsctlr() & HSCTLR_M_BIT) != 0U;
84 	}
85 }
86 
is_dcache_enabled(void)87 bool is_dcache_enabled(void)
88 {
89 	if (IS_IN_EL2()) {
90 		return (read_hsctlr() & HSCTLR_C_BIT) != 0U;
91 	} else {
92 		return (read_sctlr() & SCTLR_C_BIT) != 0U;
93 	}
94 }
95 
xlat_arch_regime_get_xn_desc(int xlat_regime)96 uint64_t xlat_arch_regime_get_xn_desc(int xlat_regime)
97 {
98 	if (xlat_regime == EL1_EL0_REGIME) {
99 		return UPPER_ATTRS(XN) | UPPER_ATTRS(PXN);
100 	} else {
101 		assert(xlat_regime == EL2_REGIME);
102 		return UPPER_ATTRS(XN);
103 	}
104 }
105 
xlat_arch_tlbi_va(uintptr_t va,int xlat_regime)106 void xlat_arch_tlbi_va(uintptr_t va, int xlat_regime)
107 {
108 	/*
109 	 * Ensure the translation table write has drained into memory before
110 	 * invalidating the TLB entry.
111 	 */
112 	dsbishst();
113 
114 	if (xlat_regime == EL1_EL0_REGIME) {
115 		tlbimvaais(TLBI_ADDR(va));
116 	} else {
117 		assert(xlat_regime == EL2_REGIME);
118 		tlbimvahis(TLBI_ADDR(va));
119 	}
120 }
121 
xlat_arch_tlbi_va_sync(void)122 void xlat_arch_tlbi_va_sync(void)
123 {
124 	/* Invalidate all entries from branch predictors. */
125 	bpiallis();
126 
127 	/*
128 	 * A TLB maintenance instruction can complete at any time after
129 	 * it is issued, but is only guaranteed to be complete after the
130 	 * execution of DSB by the PE that executed the TLB maintenance
131 	 * instruction. After the TLB invalidate instruction is
132 	 * complete, no new memory accesses using the invalidated TLB
133 	 * entries will be observed by any observer of the system
134 	 * domain. See section D4.8.2 of the ARMv8 (issue k), paragraph
135 	 * "Ordering and completion of TLB maintenance instructions".
136 	 */
137 	dsbish();
138 
139 	/*
140 	 * The effects of a completed TLB maintenance instruction are
141 	 * only guaranteed to be visible on the PE that executed the
142 	 * instruction after the execution of an ISB instruction by the
143 	 * PE that executed the TLB maintenance instruction.
144 	 */
145 	isb();
146 }
147 
xlat_arch_current_el(void)148 unsigned int xlat_arch_current_el(void)
149 {
150 	if (IS_IN_HYP()) {
151 		return 2U;
152 	} else {
153 		assert(IS_IN_SVC() || IS_IN_MON());
154 		/*
155 		 * If EL3 is in AArch32 mode, all secure PL1 modes (Monitor,
156 		 * System, SVC, Abort, UND, IRQ and FIQ modes) execute at EL3.
157 		 *
158 		 * The PL1&0 translation regime in AArch32 behaves like the
159 		 * EL1&0 regime in AArch64 except for the XN bits, but we set
160 		 * and unset them at the same time, so there's no difference in
161 		 * practice.
162 		 */
163 		return 1U;
164 	}
165 }
166 
167 /*******************************************************************************
168  * Function for enabling the MMU in PL1 or PL2, assuming that the page tables
169  * have already been created.
170  ******************************************************************************/
setup_mmu_cfg(uint64_t * params,unsigned int flags,const uint64_t * base_table,unsigned long long max_pa,uintptr_t max_va,__unused int xlat_regime)171 void setup_mmu_cfg(uint64_t *params, unsigned int flags,
172 		   const uint64_t *base_table, unsigned long long max_pa,
173 		   uintptr_t max_va, __unused int xlat_regime)
174 {
175 	uint64_t mair, ttbr0;
176 	uint32_t ttbcr;
177 
178 	/* Set attributes in the right indices of the MAIR */
179 	mair = MAIR0_ATTR_SET(ATTR_DEVICE, ATTR_DEVICE_INDEX);
180 	mair |= MAIR0_ATTR_SET(ATTR_IWBWA_OWBWA_NTR,
181 			ATTR_IWBWA_OWBWA_NTR_INDEX);
182 	mair |= MAIR0_ATTR_SET(ATTR_NON_CACHEABLE,
183 			ATTR_NON_CACHEABLE_INDEX);
184 
185 	/*
186 	 * Configure the control register for stage 1 of the PL1&0 or EL2
187 	 * translation regimes.
188 	 */
189 
190 	/* Use the Long-descriptor translation table format. */
191 	ttbcr = TTBCR_EAE_BIT;
192 
193 	if (xlat_regime == EL1_EL0_REGIME) {
194 		assert(IS_IN_SVC() || IS_IN_MON());
195 		/*
196 		 * Disable translation table walk for addresses that are
197 		 * translated using TTBR1. Therefore, only TTBR0 is used.
198 		 */
199 		ttbcr |= TTBCR_EPD1_BIT;
200 	} else {
201 		assert(xlat_regime == EL2_REGIME);
202 		assert(IS_IN_HYP());
203 
204 		/*
205 		 * Set HTCR bits as well. Set HTTBR table properties
206 		 * as Inner & outer WBWA & shareable.
207 		 */
208 		ttbcr |= HTCR_RES1 |
209 			 HTCR_SH0_INNER_SHAREABLE | HTCR_RGN0_OUTER_WBA |
210 			 HTCR_RGN0_INNER_WBA;
211 	}
212 
213 	/*
214 	 * Limit the input address ranges and memory region sizes translated
215 	 * using TTBR0 to the given virtual address space size, if smaller than
216 	 * 32 bits.
217 	 */
218 	if (max_va != UINT32_MAX) {
219 		uintptr_t virtual_addr_space_size = max_va + 1U;
220 
221 		assert(virtual_addr_space_size >=
222 			xlat_get_min_virt_addr_space_size());
223 		assert(IS_POWER_OF_TWO(virtual_addr_space_size));
224 
225 		/*
226 		 * __builtin_ctzll(0) is undefined but here we are guaranteed
227 		 * that virtual_addr_space_size is in the range [1, UINT32_MAX].
228 		 */
229 		int t0sz = 32 - __builtin_ctzll(virtual_addr_space_size);
230 
231 		ttbcr |= (uint32_t) t0sz;
232 	}
233 
234 	/*
235 	 * Set the cacheability and shareability attributes for memory
236 	 * associated with translation table walks using TTBR0.
237 	 */
238 	if ((flags & XLAT_TABLE_NC) != 0U) {
239 		/* Inner & outer non-cacheable non-shareable. */
240 		ttbcr |= TTBCR_SH0_NON_SHAREABLE | TTBCR_RGN0_OUTER_NC |
241 			TTBCR_RGN0_INNER_NC;
242 	} else {
243 		/* Inner & outer WBWA & shareable. */
244 		ttbcr |= TTBCR_SH0_INNER_SHAREABLE | TTBCR_RGN0_OUTER_WBA |
245 			TTBCR_RGN0_INNER_WBA;
246 	}
247 
248 	/* Set TTBR0 bits as well */
249 	ttbr0 = (uint64_t)(uintptr_t) base_table;
250 
251 	if (is_armv8_2_ttcnp_present()) {
252 		/* Enable CnP bit so as to share page tables with all PEs. */
253 		ttbr0 |= TTBR_CNP_BIT;
254 	}
255 
256 	/* Now populate MMU configuration */
257 	params[MMU_CFG_MAIR] = mair;
258 	params[MMU_CFG_TCR] = (uint64_t) ttbcr;
259 	params[MMU_CFG_TTBR0] = ttbr0;
260 }
261