xref: /freebsd/sys/arm64/arm64/efirt_machdep.c (revision 4b9d6057)
1 /*-
2  * Copyright (c) 2004 Marcel Moolenaar
3  * Copyright (c) 2001 Doug Rabson
4  * Copyright (c) 2016 The FreeBSD Foundation
5  * Copyright (c) 2017 Andrew Turner
6  * All rights reserved.
7  *
8  * Portions of this software were developed by Konstantin Belousov
9  * under sponsorship from the FreeBSD Foundation.
10  *
11  * This software was developed by SRI International and the University of
12  * Cambridge Computer Laboratory under DARPA/AFRL contract FA8750-10-C-0237
13  * ("CTSRD"), as part of the DARPA CRASH research programme.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include <sys/param.h>
38 #include <sys/efi.h>
39 #include <sys/kernel.h>
40 #include <sys/linker.h>
41 #include <sys/lock.h>
42 #include <sys/mutex.h>
43 #include <sys/proc.h>
44 #include <sys/rwlock.h>
45 #include <sys/systm.h>
46 #include <sys/vmmeter.h>
47 
48 #include <machine/pte.h>
49 #include <machine/vmparam.h>
50 
51 #include <vm/vm.h>
52 #include <vm/pmap.h>
53 #include <vm/vm_map.h>
54 #include <vm/vm_object.h>
55 #include <vm/vm_page.h>
56 #include <vm/vm_pager.h>
57 
58 static vm_object_t obj_1t1_pt;
59 static vm_pindex_t efi_1t1_idx;
60 static pd_entry_t *efi_l0;
61 static uint64_t efi_ttbr0;
62 
63 void
64 efi_destroy_1t1_map(void)
65 {
66 	vm_page_t m;
67 
68 	if (obj_1t1_pt != NULL) {
69 		VM_OBJECT_RLOCK(obj_1t1_pt);
70 		TAILQ_FOREACH(m, &obj_1t1_pt->memq, listq)
71 			m->ref_count = VPRC_OBJREF;
72 		vm_wire_sub(obj_1t1_pt->resident_page_count);
73 		VM_OBJECT_RUNLOCK(obj_1t1_pt);
74 		vm_object_deallocate(obj_1t1_pt);
75 	}
76 
77 	obj_1t1_pt = NULL;
78 	efi_1t1_idx = 0;
79 	efi_l0 = NULL;
80 	efi_ttbr0 = 0;
81 }
82 
83 static vm_page_t
84 efi_1t1_page(void)
85 {
86 
87 	return (vm_page_grab(obj_1t1_pt, efi_1t1_idx++, VM_ALLOC_NOBUSY |
88 	    VM_ALLOC_WIRED | VM_ALLOC_ZERO));
89 }
90 
91 static pt_entry_t *
92 efi_1t1_l3(vm_offset_t va)
93 {
94 	pd_entry_t *l0, *l1, *l2;
95 	pt_entry_t *l3;
96 	vm_pindex_t l0_idx, l1_idx, l2_idx;
97 	vm_page_t m;
98 	vm_paddr_t mphys;
99 
100 	l0_idx = pmap_l0_index(va);
101 	l0 = &efi_l0[l0_idx];
102 	if (*l0 == 0) {
103 		m = efi_1t1_page();
104 		mphys = VM_PAGE_TO_PHYS(m);
105 		*l0 = PHYS_TO_PTE(mphys) | L0_TABLE;
106 	} else {
107 		mphys = PTE_TO_PHYS(*l0);
108 	}
109 
110 	l1 = (pd_entry_t *)PHYS_TO_DMAP(mphys);
111 	l1_idx = pmap_l1_index(va);
112 	l1 += l1_idx;
113 	if (*l1 == 0) {
114 		m = efi_1t1_page();
115 		mphys = VM_PAGE_TO_PHYS(m);
116 		*l1 = PHYS_TO_PTE(mphys) | L1_TABLE;
117 	} else {
118 		mphys = PTE_TO_PHYS(*l1);
119 	}
120 
121 	l2 = (pd_entry_t *)PHYS_TO_DMAP(mphys);
122 	l2_idx = pmap_l2_index(va);
123 	l2 += l2_idx;
124 	if (*l2 == 0) {
125 		m = efi_1t1_page();
126 		mphys = VM_PAGE_TO_PHYS(m);
127 		*l2 = PHYS_TO_PTE(mphys) | L2_TABLE;
128 	} else {
129 		mphys = PTE_TO_PHYS(*l2);
130 	}
131 
132 	l3 = (pt_entry_t *)PHYS_TO_DMAP(mphys);
133 	l3 += pmap_l3_index(va);
134 	KASSERT(*l3 == 0, ("%s: Already mapped: va %#jx *pt %#jx", __func__,
135 	    va, *l3));
136 
137 	return (l3);
138 }
139 
140 /*
141  * Map a physical address from EFI runtime space into KVA space.  Returns 0 to
142  * indicate a failed mapping so that the caller may handle error.
143  */
144 vm_offset_t
145 efi_phys_to_kva(vm_paddr_t paddr)
146 {
147 	vm_offset_t vaddr;
148 
149 	if (PHYS_IN_DMAP(paddr)) {
150 		vaddr = PHYS_TO_DMAP(paddr);
151 		if (pmap_klookup(vaddr, NULL))
152 			return (vaddr);
153 	}
154 
155 	/* TODO: Map memory not in the DMAP */
156 
157 	return (0);
158 }
159 
160 /*
161  * Create the 1:1 virtual to physical map for EFI
162  */
163 bool
164 efi_create_1t1_map(struct efi_md *map, int ndesc, int descsz)
165 {
166 	struct efi_md *p;
167 	pt_entry_t *l3, l3_attr;
168 	vm_offset_t va;
169 	vm_page_t efi_l0_page;
170 	uint64_t idx;
171 	int i, mode;
172 
173 	obj_1t1_pt = vm_pager_allocate(OBJT_PHYS, NULL, L0_ENTRIES +
174 	    L0_ENTRIES * Ln_ENTRIES + L0_ENTRIES * Ln_ENTRIES * Ln_ENTRIES +
175 	    L0_ENTRIES * Ln_ENTRIES * Ln_ENTRIES * Ln_ENTRIES,
176 	    VM_PROT_ALL, 0, NULL);
177 	VM_OBJECT_WLOCK(obj_1t1_pt);
178 	efi_l0_page = efi_1t1_page();
179 	VM_OBJECT_WUNLOCK(obj_1t1_pt);
180 	efi_l0 = (pd_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(efi_l0_page));
181 	efi_ttbr0 = ASID_TO_OPERAND(ASID_RESERVED_FOR_EFI) |
182 	    VM_PAGE_TO_PHYS(efi_l0_page);
183 
184 	for (i = 0, p = map; i < ndesc; i++, p = efi_next_descriptor(p,
185 	    descsz)) {
186 		if ((p->md_attr & EFI_MD_ATTR_RT) == 0)
187 			continue;
188 		if (p->md_virt != 0 && p->md_virt != p->md_phys) {
189 			if (bootverbose)
190 				printf("EFI Runtime entry %d is mapped\n", i);
191 			goto fail;
192 		}
193 		if ((p->md_phys & EFI_PAGE_MASK) != 0) {
194 			if (bootverbose)
195 				printf("EFI Runtime entry %d is not aligned\n",
196 				    i);
197 			goto fail;
198 		}
199 		if (p->md_phys + p->md_pages * EFI_PAGE_SIZE < p->md_phys ||
200 		    p->md_phys + p->md_pages * EFI_PAGE_SIZE >=
201 		    VM_MAXUSER_ADDRESS) {
202 			printf("EFI Runtime entry %d is not in mappable for RT:"
203 			    "base %#016jx %#jx pages\n",
204 			    i, (uintmax_t)p->md_phys,
205 			    (uintmax_t)p->md_pages);
206 			goto fail;
207 		}
208 		if ((p->md_attr & EFI_MD_ATTR_WB) != 0)
209 			mode = VM_MEMATTR_WRITE_BACK;
210 		else if ((p->md_attr & EFI_MD_ATTR_WT) != 0)
211 			mode = VM_MEMATTR_WRITE_THROUGH;
212 		else if ((p->md_attr & EFI_MD_ATTR_WC) != 0)
213 			mode = VM_MEMATTR_WRITE_COMBINING;
214 		else
215 			mode = VM_MEMATTR_DEVICE;
216 
217 		if (bootverbose) {
218 			printf("MAP %lx mode %x pages %lu\n",
219 			    p->md_phys, mode, p->md_pages);
220 		}
221 
222 		l3_attr = ATTR_DEFAULT | ATTR_S1_IDX(mode) |
223 		    ATTR_S1_AP(ATTR_S1_AP_RW) | ATTR_S1_nG | L3_PAGE;
224 		if (mode == VM_MEMATTR_DEVICE || p->md_attr & EFI_MD_ATTR_XP)
225 			l3_attr |= ATTR_S1_XN;
226 
227 		VM_OBJECT_WLOCK(obj_1t1_pt);
228 		for (va = p->md_phys, idx = 0; idx < p->md_pages;
229 		    idx += (PAGE_SIZE / EFI_PAGE_SIZE), va += PAGE_SIZE) {
230 			l3 = efi_1t1_l3(va);
231 			*l3 = va | l3_attr;
232 		}
233 		VM_OBJECT_WUNLOCK(obj_1t1_pt);
234 	}
235 
236 	return (true);
237 fail:
238 	efi_destroy_1t1_map();
239 	return (false);
240 }
241 
242 int
243 efi_arch_enter(void)
244 {
245 
246 	CRITICAL_ASSERT(curthread);
247 
248 	/*
249 	 * Temporarily switch to EFI's page table.  However, we leave curpmap
250 	 * unchanged in order to prevent its ASID from being reclaimed before
251 	 * we switch back to its page table in efi_arch_leave().
252 	 */
253 	set_ttbr0(efi_ttbr0);
254 	if (PCPU_GET(bcast_tlbi_workaround) != 0)
255 		invalidate_local_icache();
256 
257 	return (0);
258 }
259 
260 void
261 efi_arch_leave(void)
262 {
263 
264 	/*
265 	 * Restore the pcpu pointer. Some UEFI implementations trash it and
266 	 * we don't store it before calling into them. To fix this we need
267 	 * to restore it after returning to the kernel context. As reading
268 	 * curpmap will access x18 we need to restore it before loading
269 	 * the pmap pointer.
270 	 */
271 	__asm __volatile(
272 	    "mrs x18, tpidr_el1	\n"
273 	);
274 	set_ttbr0(pmap_to_ttbr0(PCPU_GET(curpmap)));
275 	if (PCPU_GET(bcast_tlbi_workaround) != 0)
276 		invalidate_local_icache();
277 }
278 
279 int
280 efi_rt_arch_call(struct efirt_callinfo *ec)
281 {
282 
283 	panic("not implemented");
284 }
285