hc
2023-12-11 d2ccde1c8e90d38cee87a1b0309ad2827f3fd30d
kernel/drivers/firmware/efi/libstub/arm32-stub.c
....@@ -1,19 +1,54 @@
1
+// SPDX-License-Identifier: GPL-2.0
12 /*
23 * Copyright (C) 2013 Linaro Ltd; <roy.franz@linaro.org>
3
- *
4
- * This program is free software; you can redistribute it and/or modify
5
- * it under the terms of the GNU General Public License version 2 as
6
- * published by the Free Software Foundation.
7
- *
84 */
95 #include <linux/efi.h>
106 #include <asm/efi.h>
117
128 #include "efistub.h"
139
14
-efi_status_t check_platform_features(efi_system_table_t *sys_table_arg)
10
+static efi_guid_t cpu_state_guid = LINUX_EFI_ARM_CPU_STATE_TABLE_GUID;
11
+
12
+struct efi_arm_entry_state *efi_entry_state;
13
+
14
+static void get_cpu_state(u32 *cpsr, u32 *sctlr)
1515 {
16
+ asm("mrs %0, cpsr" : "=r"(*cpsr));
17
+ if ((*cpsr & MODE_MASK) == HYP_MODE)
18
+ asm("mrc p15, 4, %0, c1, c0, 0" : "=r"(*sctlr));
19
+ else
20
+ asm("mrc p15, 0, %0, c1, c0, 0" : "=r"(*sctlr));
21
+}
22
+
23
+efi_status_t check_platform_features(void)
24
+{
25
+ efi_status_t status;
26
+ u32 cpsr, sctlr;
1627 int block;
28
+
29
+ get_cpu_state(&cpsr, &sctlr);
30
+
31
+ efi_info("Entering in %s mode with MMU %sabled\n",
32
+ ((cpsr & MODE_MASK) == HYP_MODE) ? "HYP" : "SVC",
33
+ (sctlr & 1) ? "en" : "dis");
34
+
35
+ status = efi_bs_call(allocate_pool, EFI_LOADER_DATA,
36
+ sizeof(*efi_entry_state),
37
+ (void **)&efi_entry_state);
38
+ if (status != EFI_SUCCESS) {
39
+ efi_err("allocate_pool() failed\n");
40
+ return status;
41
+ }
42
+
43
+ efi_entry_state->cpsr_before_ebs = cpsr;
44
+ efi_entry_state->sctlr_before_ebs = sctlr;
45
+
46
+ status = efi_bs_call(install_configuration_table, &cpu_state_guid,
47
+ efi_entry_state);
48
+ if (status != EFI_SUCCESS) {
49
+ efi_err("install_configuration_table() failed\n");
50
+ goto free_state;
51
+ }
1752
1853 /* non-LPAE kernels can run anywhere */
1954 if (!IS_ENABLED(CONFIG_ARM_LPAE))
....@@ -22,15 +57,28 @@
2257 /* LPAE kernels need compatible hardware */
2358 block = cpuid_feature_extract(CPUID_EXT_MMFR0, 0);
2459 if (block < 5) {
25
- pr_efi_err(sys_table_arg, "This LPAE kernel is not supported by your CPU\n");
26
- return EFI_UNSUPPORTED;
60
+ efi_err("This LPAE kernel is not supported by your CPU\n");
61
+ status = EFI_UNSUPPORTED;
62
+ goto drop_table;
2763 }
2864 return EFI_SUCCESS;
65
+
66
+drop_table:
67
+ efi_bs_call(install_configuration_table, &cpu_state_guid, NULL);
68
+free_state:
69
+ efi_bs_call(free_pool, efi_entry_state);
70
+ return status;
71
+}
72
+
73
+void efi_handle_post_ebs_state(void)
74
+{
75
+ get_cpu_state(&efi_entry_state->cpsr_after_ebs,
76
+ &efi_entry_state->sctlr_after_ebs);
2977 }
3078
3179 static efi_guid_t screen_info_guid = LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID;
3280
33
-struct screen_info *alloc_screen_info(efi_system_table_t *sys_table_arg)
81
+struct screen_info *alloc_screen_info(void)
3482 {
3583 struct screen_info *si;
3684 efi_status_t status;
....@@ -41,209 +89,82 @@
4189 * its contents while we hand over to the kernel proper from the
4290 * decompressor.
4391 */
44
- status = efi_call_early(allocate_pool, EFI_RUNTIME_SERVICES_DATA,
45
- sizeof(*si), (void **)&si);
92
+ status = efi_bs_call(allocate_pool, EFI_RUNTIME_SERVICES_DATA,
93
+ sizeof(*si), (void **)&si);
4694
4795 if (status != EFI_SUCCESS)
4896 return NULL;
4997
50
- status = efi_call_early(install_configuration_table,
51
- &screen_info_guid, si);
98
+ status = efi_bs_call(install_configuration_table,
99
+ &screen_info_guid, si);
52100 if (status == EFI_SUCCESS)
53101 return si;
54102
55
- efi_call_early(free_pool, si);
103
+ efi_bs_call(free_pool, si);
56104 return NULL;
57105 }
58106
59
-void free_screen_info(efi_system_table_t *sys_table_arg, struct screen_info *si)
107
+void free_screen_info(struct screen_info *si)
60108 {
61109 if (!si)
62110 return;
63111
64
- efi_call_early(install_configuration_table, &screen_info_guid, NULL);
65
- efi_call_early(free_pool, si);
112
+ efi_bs_call(install_configuration_table, &screen_info_guid, NULL);
113
+ efi_bs_call(free_pool, si);
66114 }
67115
68
-static efi_status_t reserve_kernel_base(efi_system_table_t *sys_table_arg,
69
- unsigned long dram_base,
70
- unsigned long *reserve_addr,
71
- unsigned long *reserve_size)
72
-{
73
- efi_physical_addr_t alloc_addr;
74
- efi_memory_desc_t *memory_map;
75
- unsigned long nr_pages, map_size, desc_size, buff_size;
76
- efi_status_t status;
77
- unsigned long l;
78
-
79
- struct efi_boot_memmap map = {
80
- .map = &memory_map,
81
- .map_size = &map_size,
82
- .desc_size = &desc_size,
83
- .desc_ver = NULL,
84
- .key_ptr = NULL,
85
- .buff_size = &buff_size,
86
- };
87
-
88
- /*
89
- * Reserve memory for the uncompressed kernel image. This is
90
- * all that prevents any future allocations from conflicting
91
- * with the kernel. Since we can't tell from the compressed
92
- * image how much DRAM the kernel actually uses (due to BSS
93
- * size uncertainty) we allocate the maximum possible size.
94
- * Do this very early, as prints can cause memory allocations
95
- * that may conflict with this.
96
- */
97
- alloc_addr = dram_base + MAX_UNCOMP_KERNEL_SIZE;
98
- nr_pages = MAX_UNCOMP_KERNEL_SIZE / EFI_PAGE_SIZE;
99
- status = efi_call_early(allocate_pages, EFI_ALLOCATE_MAX_ADDRESS,
100
- EFI_BOOT_SERVICES_DATA, nr_pages, &alloc_addr);
101
- if (status == EFI_SUCCESS) {
102
- if (alloc_addr == dram_base) {
103
- *reserve_addr = alloc_addr;
104
- *reserve_size = MAX_UNCOMP_KERNEL_SIZE;
105
- return EFI_SUCCESS;
106
- }
107
- /*
108
- * If we end up here, the allocation succeeded but starts below
109
- * dram_base. This can only occur if the real base of DRAM is
110
- * not a multiple of 128 MB, in which case dram_base will have
111
- * been rounded up. Since this implies that a part of the region
112
- * was already occupied, we need to fall through to the code
113
- * below to ensure that the existing allocations don't conflict.
114
- * For this reason, we use EFI_BOOT_SERVICES_DATA above and not
115
- * EFI_LOADER_DATA, which we wouldn't able to distinguish from
116
- * allocations that we want to disallow.
117
- */
118
- }
119
-
120
- /*
121
- * If the allocation above failed, we may still be able to proceed:
122
- * if the only allocations in the region are of types that will be
123
- * released to the OS after ExitBootServices(), the decompressor can
124
- * safely overwrite them.
125
- */
126
- status = efi_get_memory_map(sys_table_arg, &map);
127
- if (status != EFI_SUCCESS) {
128
- pr_efi_err(sys_table_arg,
129
- "reserve_kernel_base(): Unable to retrieve memory map.\n");
130
- return status;
131
- }
132
-
133
- for (l = 0; l < map_size; l += desc_size) {
134
- efi_memory_desc_t *desc;
135
- u64 start, end;
136
-
137
- desc = (void *)memory_map + l;
138
- start = desc->phys_addr;
139
- end = start + desc->num_pages * EFI_PAGE_SIZE;
140
-
141
- /* Skip if entry does not intersect with region */
142
- if (start >= dram_base + MAX_UNCOMP_KERNEL_SIZE ||
143
- end <= dram_base)
144
- continue;
145
-
146
- switch (desc->type) {
147
- case EFI_BOOT_SERVICES_CODE:
148
- case EFI_BOOT_SERVICES_DATA:
149
- /* Ignore types that are released to the OS anyway */
150
- continue;
151
-
152
- case EFI_CONVENTIONAL_MEMORY:
153
- /*
154
- * Reserve the intersection between this entry and the
155
- * region.
156
- */
157
- start = max(start, (u64)dram_base);
158
- end = min(end, (u64)dram_base + MAX_UNCOMP_KERNEL_SIZE);
159
-
160
- status = efi_call_early(allocate_pages,
161
- EFI_ALLOCATE_ADDRESS,
162
- EFI_LOADER_DATA,
163
- (end - start) / EFI_PAGE_SIZE,
164
- &start);
165
- if (status != EFI_SUCCESS) {
166
- pr_efi_err(sys_table_arg,
167
- "reserve_kernel_base(): alloc failed.\n");
168
- goto out;
169
- }
170
- break;
171
-
172
- case EFI_LOADER_CODE:
173
- case EFI_LOADER_DATA:
174
- /*
175
- * These regions may be released and reallocated for
176
- * another purpose (including EFI_RUNTIME_SERVICE_DATA)
177
- * at any time during the execution of the OS loader,
178
- * so we cannot consider them as safe.
179
- */
180
- default:
181
- /*
182
- * Treat any other allocation in the region as unsafe */
183
- status = EFI_OUT_OF_RESOURCES;
184
- goto out;
185
- }
186
- }
187
-
188
- status = EFI_SUCCESS;
189
-out:
190
- efi_call_early(free_pool, memory_map);
191
- return status;
192
-}
193
-
194
-efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
195
- unsigned long *image_addr,
116
+efi_status_t handle_kernel_image(unsigned long *image_addr,
196117 unsigned long *image_size,
197118 unsigned long *reserve_addr,
198119 unsigned long *reserve_size,
199
- unsigned long dram_base,
200120 efi_loaded_image_t *image)
201121 {
122
+ const int slack = TEXT_OFFSET - 5 * PAGE_SIZE;
123
+ int alloc_size = MAX_UNCOMP_KERNEL_SIZE + EFI_PHYS_ALIGN;
124
+ unsigned long alloc_base, kernel_base;
202125 efi_status_t status;
203126
204127 /*
205
- * Verify that the DRAM base address is compatible with the ARM
206
- * boot protocol, which determines the base of DRAM by masking
207
- * off the low 27 bits of the address at which the zImage is
208
- * loaded. These assumptions are made by the decompressor,
209
- * before any memory map is available.
128
+ * Allocate space for the decompressed kernel as low as possible.
129
+ * The region should be 16 MiB aligned, but the first 'slack' bytes
130
+ * are not used by Linux, so we allow those to be occupied by the
131
+ * firmware.
210132 */
211
- dram_base = round_up(dram_base, SZ_128M);
212
-
213
- status = reserve_kernel_base(sys_table, dram_base, reserve_addr,
214
- reserve_size);
133
+ status = efi_low_alloc_above(alloc_size, EFI_PAGE_SIZE, &alloc_base, 0x0);
215134 if (status != EFI_SUCCESS) {
216
- pr_efi_err(sys_table, "Unable to allocate memory for uncompressed kernel.\n");
135
+ efi_err("Unable to allocate memory for uncompressed kernel.\n");
217136 return status;
218137 }
219138
220
- /*
221
- * Relocate the zImage, so that it appears in the lowest 128 MB
222
- * memory window.
223
- */
224
- *image_size = image->image_size;
225
- status = efi_relocate_kernel(sys_table, image_addr, *image_size,
226
- *image_size,
227
- dram_base + MAX_UNCOMP_KERNEL_SIZE, 0);
228
- if (status != EFI_SUCCESS) {
229
- pr_efi_err(sys_table, "Failed to relocate kernel.\n");
230
- efi_free(sys_table, *reserve_size, *reserve_addr);
231
- *reserve_size = 0;
232
- return status;
139
+ if ((alloc_base % EFI_PHYS_ALIGN) > slack) {
140
+ /*
141
+ * More than 'slack' bytes are already occupied at the base of
142
+ * the allocation, so we need to advance to the next 16 MiB block.
143
+ */
144
+ kernel_base = round_up(alloc_base, EFI_PHYS_ALIGN);
145
+ efi_info("Free memory starts at 0x%lx, setting kernel_base to 0x%lx\n",
146
+ alloc_base, kernel_base);
147
+ } else {
148
+ kernel_base = round_down(alloc_base, EFI_PHYS_ALIGN);
233149 }
234150
235
- /*
236
- * Check to see if we were able to allocate memory low enough
237
- * in memory. The kernel determines the base of DRAM from the
238
- * address at which the zImage is loaded.
239
- */
240
- if (*image_addr + *image_size > dram_base + ZIMAGE_OFFSET_LIMIT) {
241
- pr_efi_err(sys_table, "Failed to relocate kernel, no low memory available.\n");
242
- efi_free(sys_table, *reserve_size, *reserve_addr);
243
- *reserve_size = 0;
244
- efi_free(sys_table, *image_size, *image_addr);
245
- *image_size = 0;
246
- return EFI_LOAD_ERROR;
151
+ *reserve_addr = kernel_base + slack;
152
+ *reserve_size = MAX_UNCOMP_KERNEL_SIZE;
153
+
154
+ /* now free the parts that we will not use */
155
+ if (*reserve_addr > alloc_base) {
156
+ efi_bs_call(free_pages, alloc_base,
157
+ (*reserve_addr - alloc_base) / EFI_PAGE_SIZE);
158
+ alloc_size -= *reserve_addr - alloc_base;
247159 }
160
+ efi_bs_call(free_pages, *reserve_addr + MAX_UNCOMP_KERNEL_SIZE,
161
+ (alloc_size - MAX_UNCOMP_KERNEL_SIZE) / EFI_PAGE_SIZE);
162
+
163
+ *image_addr = kernel_base + TEXT_OFFSET;
164
+ *image_size = 0;
165
+
166
+ efi_debug("image addr == 0x%lx, reserve_addr == 0x%lx\n",
167
+ *image_addr, *reserve_addr);
168
+
248169 return EFI_SUCCESS;
249170 }