xref: /freebsd/sys/arm64/arm64/efirt_machdep.c (revision 9d40492e)
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
efi_destroy_1t1_map(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
efi_1t1_page(void)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 *
efi_1t1_l3(vm_offset_t va)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
efi_phys_to_kva(vm_paddr_t paddr)145 efi_phys_to_kva(vm_paddr_t paddr)
146 {
147 	if (PHYS_IN_DMAP(paddr))
148 		return (PHYS_TO_DMAP(paddr));
149 
150 	/* TODO: Map memory not in the DMAP */
151 
152 	return (0);
153 }
154 
155 /*
156  * Create the 1:1 virtual to physical map for EFI
157  */
158 bool
efi_create_1t1_map(struct efi_md * map,int ndesc,int descsz)159 efi_create_1t1_map(struct efi_md *map, int ndesc, int descsz)
160 {
161 	struct efi_md *p;
162 	pt_entry_t *l3, l3_attr;
163 	vm_offset_t va;
164 	vm_page_t efi_l0_page;
165 	uint64_t idx;
166 	int i, mode;
167 
168 	obj_1t1_pt = vm_pager_allocate(OBJT_PHYS, NULL, L0_ENTRIES +
169 	    L0_ENTRIES * Ln_ENTRIES + L0_ENTRIES * Ln_ENTRIES * Ln_ENTRIES +
170 	    L0_ENTRIES * Ln_ENTRIES * Ln_ENTRIES * Ln_ENTRIES,
171 	    VM_PROT_ALL, 0, NULL);
172 	VM_OBJECT_WLOCK(obj_1t1_pt);
173 	efi_l0_page = efi_1t1_page();
174 	VM_OBJECT_WUNLOCK(obj_1t1_pt);
175 	efi_l0 = (pd_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(efi_l0_page));
176 	efi_ttbr0 = ASID_TO_OPERAND(ASID_RESERVED_FOR_EFI) |
177 	    VM_PAGE_TO_PHYS(efi_l0_page);
178 
179 	for (i = 0, p = map; i < ndesc; i++, p = efi_next_descriptor(p,
180 	    descsz)) {
181 		if ((p->md_attr & EFI_MD_ATTR_RT) == 0)
182 			continue;
183 		if (p->md_virt != 0 && p->md_virt != p->md_phys) {
184 			if (bootverbose)
185 				printf("EFI Runtime entry %d is mapped\n", i);
186 			goto fail;
187 		}
188 		if ((p->md_phys & EFI_PAGE_MASK) != 0) {
189 			if (bootverbose)
190 				printf("EFI Runtime entry %d is not aligned\n",
191 				    i);
192 			goto fail;
193 		}
194 		if (p->md_phys + p->md_pages * EFI_PAGE_SIZE < p->md_phys ||
195 		    p->md_phys + p->md_pages * EFI_PAGE_SIZE >=
196 		    VM_MAXUSER_ADDRESS) {
197 			printf("EFI Runtime entry %d is not in mappable for RT:"
198 			    "base %#016jx %#jx pages\n",
199 			    i, (uintmax_t)p->md_phys,
200 			    (uintmax_t)p->md_pages);
201 			goto fail;
202 		}
203 		if ((p->md_attr & EFI_MD_ATTR_WB) != 0)
204 			mode = VM_MEMATTR_WRITE_BACK;
205 		else if ((p->md_attr & EFI_MD_ATTR_WT) != 0)
206 			mode = VM_MEMATTR_WRITE_THROUGH;
207 		else if ((p->md_attr & EFI_MD_ATTR_WC) != 0)
208 			mode = VM_MEMATTR_WRITE_COMBINING;
209 		else
210 			mode = VM_MEMATTR_DEVICE;
211 
212 		if (bootverbose) {
213 			printf("MAP %lx mode %x pages %lu\n",
214 			    p->md_phys, mode, p->md_pages);
215 		}
216 
217 		l3_attr = ATTR_DEFAULT | ATTR_S1_IDX(mode) |
218 		    ATTR_S1_AP(ATTR_S1_AP_RW) | ATTR_S1_nG | L3_PAGE;
219 		if (mode == VM_MEMATTR_DEVICE || p->md_attr & EFI_MD_ATTR_XP)
220 			l3_attr |= ATTR_S1_XN;
221 
222 		VM_OBJECT_WLOCK(obj_1t1_pt);
223 		for (va = p->md_phys, idx = 0; idx < p->md_pages;
224 		    idx += (PAGE_SIZE / EFI_PAGE_SIZE), va += PAGE_SIZE) {
225 			l3 = efi_1t1_l3(va);
226 			*l3 = va | l3_attr;
227 		}
228 		VM_OBJECT_WUNLOCK(obj_1t1_pt);
229 	}
230 
231 	return (true);
232 fail:
233 	efi_destroy_1t1_map();
234 	return (false);
235 }
236 
237 int
efi_arch_enter(void)238 efi_arch_enter(void)
239 {
240 
241 	CRITICAL_ASSERT(curthread);
242 
243 	/*
244 	 * Temporarily switch to EFI's page table.  However, we leave curpmap
245 	 * unchanged in order to prevent its ASID from being reclaimed before
246 	 * we switch back to its page table in efi_arch_leave().
247 	 */
248 	set_ttbr0(efi_ttbr0);
249 	if (PCPU_GET(bcast_tlbi_workaround) != 0)
250 		invalidate_local_icache();
251 
252 	return (0);
253 }
254 
255 void
efi_arch_leave(void)256 efi_arch_leave(void)
257 {
258 
259 	/*
260 	 * Restore the pcpu pointer. Some UEFI implementations trash it and
261 	 * we don't store it before calling into them. To fix this we need
262 	 * to restore it after returning to the kernel context. As reading
263 	 * curpmap will access x18 we need to restore it before loading
264 	 * the pmap pointer.
265 	 */
266 	__asm __volatile(
267 	    "mrs x18, tpidr_el1	\n"
268 	);
269 	set_ttbr0(pmap_to_ttbr0(PCPU_GET(curpmap)));
270 	if (PCPU_GET(bcast_tlbi_workaround) != 0)
271 		invalidate_local_icache();
272 }
273 
274 int
efi_rt_arch_call(struct efirt_callinfo * ec)275 efi_rt_arch_call(struct efirt_callinfo *ec)
276 {
277 
278 	panic("not implemented");
279 }
280