arch/arm/cpu/armv8/sec_firmware.c

   1 /*
   2  * Copyright 2016 NXP Semiconductor, Inc.
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8 #include <errno.h>
   9 #include <linux/kernel.h>
  10 #include <asm/io.h>
  11 #include <asm/system.h>
  12 #include <asm/types.h>
  13 #include <asm/macro.h>
  14 #include <asm/armv8/sec_firmware.h>
  15
  16 DECLARE_GLOBAL_DATA_PTR;
  17 extern void c_runtime_cpu_setup(void);
  18
  19 #define SEC_FIRMWARE_LOADED     0x1
  20 #define SEC_FIRMWARE_RUNNING    0x2
  21 #define SEC_FIRMWARE_ADDR_MASK  (~0x3)
  22         /*
  23          * Secure firmware load addr
  24          * Flags used: 0x1 secure firmware has been loaded to secure memory
  25          *             0x2 secure firmware is running
  26          */
  27         phys_addr_t sec_firmware_addr;
  28
  29 static int sec_firmware_get_data(const void *sec_firmware_img,
  30                                 const void **data, size_t *size)
  31 {
  32         int conf_node_off, fw_node_off;
  33         char *conf_node_name = NULL;
  34         char *desc;
  35         int ret;
  36
  37         conf_node_name = SEC_FIRMEWARE_FIT_CNF_NAME;
  38
  39         conf_node_off = fit_conf_get_node(sec_firmware_img, conf_node_name);
  40         if (conf_node_off < 0) {
  41                 printf("SEC Firmware: %s: no such config\n", conf_node_name);
  42                 return -ENOENT;
  43         }
  44
  45         fw_node_off = fit_conf_get_prop_node(sec_firmware_img, conf_node_off,
  46                         SEC_FIRMWARE_FIT_IMAGE);
  47         if (fw_node_off < 0) {
  48                 printf("SEC Firmware: No '%s' in config\n",
  49                        SEC_FIRMWARE_FIT_IMAGE);
  50                 return -ENOLINK;
  51         }
  52
  53         /* Verify secure firmware image */
  54         if (!(fit_image_verify(sec_firmware_img, fw_node_off))) {
  55                 printf("SEC Firmware: Bad firmware image (bad CRC)\n");
  56                 return -EINVAL;
  57         }
  58
  59         if (fit_image_get_data(sec_firmware_img, fw_node_off, data, size)) {
  60                 printf("SEC Firmware: Can't get %s subimage data/size",
  61                        SEC_FIRMWARE_FIT_IMAGE);
  62                 return -ENOENT;
  63         }
  64
  65         ret = fit_get_desc(sec_firmware_img, fw_node_off, &desc);
  66         if (ret)
  67                 printf("SEC Firmware: Can't get description\n");
  68         else
  69                 printf("%s\n", desc);
  70
  71         return ret;
  72 }
  73
  74 /*
  75  * SEC Firmware FIT image parser checks if the image is in FIT
  76  * format, verifies integrity of the image and calculates raw
  77  * image address and size values.
  78  *
  79  * Returns 0 on success and a negative errno on error task fail.
  80  */
  81 static int sec_firmware_parse_image(const void *sec_firmware_img,
  82                                         const void **raw_image_addr,
  83                                         size_t *raw_image_size)
  84 {
  85         int ret;
  86
  87         ret = sec_firmware_get_data(sec_firmware_img, raw_image_addr,
  88                                         raw_image_size);
  89         if (ret)
  90                 return ret;
  91
  92         debug("SEC Firmware: raw_image_addr = 0x%p, raw_image_size = 0x%lx\n",
  93               *raw_image_addr, *raw_image_size);
  94
  95         return 0;
  96 }
  97
  98 static int sec_firmware_copy_image(const char *title,
  99                          u64 image_addr, u32 image_size, u64 sec_firmware)
 100 {
 101         debug("%s copied to address 0x%p\n", title, (void *)sec_firmware);
 102         memcpy((void *)sec_firmware, (void *)image_addr, image_size);
 103         flush_dcache_range(sec_firmware, sec_firmware + image_size);
 104
 105         return 0;
 106 }
 107
 108 /*
 109  * This function will parse the SEC Firmware image, and then load it
 110  * to secure memory.
 111  */
 112 static int sec_firmware_load_image(const void *sec_firmware_img)
 113 {
 114         const void *raw_image_addr;
 115         size_t raw_image_size = 0;
 116         int ret;
 117
 118         /*
 119          * The Excetpion Level must be EL3 to load and initialize
 120          * the SEC Firmware.
 121          */
 122         if (current_el() != 3) {
 123                 ret = -EACCES;
 124                 goto out;
 125         }
 126
 127 #ifdef CONFIG_SYS_MEM_RESERVE_SECURE
 128         /*
 129          * The SEC Firmware must be stored in secure memory.
 130          * Append SEC Firmware to secure mmu table.
 131          */
 132         if (!(gd->arch.secure_ram & MEM_RESERVE_SECURE_MAINTAINED)) {
 133                 ret = -ENXIO;
 134                 goto out;
 135         }
 136
 137         sec_firmware_addr = (gd->arch.secure_ram & MEM_RESERVE_SECURE_ADDR_MASK) +
 138                         gd->arch.tlb_size;
 139 #else
 140 #error "The CONFIG_SYS_MEM_RESERVE_SECURE must be defined when enabled SEC Firmware support"
 141 #endif
 142
 143         /* Align SEC Firmware base address to 4K */
 144         sec_firmware_addr = (sec_firmware_addr + 0xfff) & ~0xfff;
 145         debug("SEC Firmware: Load address: 0x%llx\n",
 146               sec_firmware_addr & SEC_FIRMWARE_ADDR_MASK);
 147
 148         ret = sec_firmware_parse_image(sec_firmware_img, &raw_image_addr,
 149                         &raw_image_size);
 150         if (ret)
 151                 goto out;
 152
 153         /* TODO:
 154          * Check if the end addr of SEC Firmware has been extend the secure
 155          * memory.
 156          */
 157
 158         /* Copy the secure firmware to secure memory */
 159         ret = sec_firmware_copy_image("SEC Firmware", (u64)raw_image_addr,
 160                         raw_image_size, sec_firmware_addr &
 161                         SEC_FIRMWARE_ADDR_MASK);
 162         if (ret)
 163                 goto out;
 164
 165         sec_firmware_addr |= SEC_FIRMWARE_LOADED;
 166         debug("SEC Firmware: Entry point: 0x%llx\n",
 167               sec_firmware_addr & SEC_FIRMWARE_ADDR_MASK);
 168
 169         return 0;
 170
 171 out:
 172         printf("SEC Firmware: error (%d)\n", ret);
 173         sec_firmware_addr = 0;
 174
 175         return ret;
 176 }
 177
 178 static int sec_firmware_entry(u32 *eret_hold_l, u32 *eret_hold_h)
 179 {
 180         const void *entry = (void *)(sec_firmware_addr &
 181                                 SEC_FIRMWARE_ADDR_MASK);
 182
 183         return _sec_firmware_entry(entry, eret_hold_l, eret_hold_h);
 184 }
 185
 186 /* Check the secure firmware FIT image */
 187 __weak bool sec_firmware_is_valid(const void *sec_firmware_img)
 188 {
 189         if (fdt_check_header(sec_firmware_img)) {
 190                 printf("SEC Firmware: Bad firmware image (not a FIT image)\n");
 191                 return false;
 192         }
 193
 194         if (!fit_check_format(sec_firmware_img)) {
 195                 printf("SEC Firmware: Bad firmware image (bad FIT header)\n");
 196                 return false;
 197         }
 198
 199         return true;
 200 }
 201
 202 #ifdef CONFIG_ARMV8_PSCI
 203 /*
 204  * The PSCI_VERSION function is added from PSCI v0.2. When the PSCI
 205  * v0.1 received this function, the NOT_SUPPORTED (0xffff_ffff) error
 206  * number will be returned according to SMC Calling Conventions. But
 207  * when getting the NOT_SUPPORTED error number, we cannot ensure if
 208  * the PSCI version is v0.1 or other error occurred. So, PSCI v0.1
 209  * won't be supported by this framework.
 210  * And if the secure firmware isn't running, return NOT_SUPPORTED.
 211  *
 212  * The return value on success is PSCI version in format
 213  * major[31:16]:minor[15:0].
 214  */
 215 unsigned int sec_firmware_support_psci_version(void)
 216 {
 217         if (sec_firmware_addr & SEC_FIRMWARE_RUNNING)
 218                 return _sec_firmware_support_psci_version();
 219
 220         return 0xffffffff;
 221 }
 222 #endif
 223
 224 /*
 225  * sec_firmware_init - Initialize the SEC Firmware
 226  * @sec_firmware_img:   the SEC Firmware image address
 227  * @eret_hold_l:        the address to hold exception return address low
 228  * @eret_hold_h:        the address to hold exception return address high
 229  */
 230 int sec_firmware_init(const void *sec_firmware_img,
 231                         u32 *eret_hold_l,
 232                         u32 *eret_hold_h)
 233 {
 234         int ret;
 235
 236         if (!sec_firmware_is_valid(sec_firmware_img))
 237                 return -EINVAL;
 238
 239         ret = sec_firmware_load_image(sec_firmware_img);
 240         if (ret) {
 241                 printf("SEC Firmware: Failed to load image\n");
 242                 return ret;
 243         } else if (sec_firmware_addr & SEC_FIRMWARE_LOADED) {
 244                 ret = sec_firmware_entry(eret_hold_l, eret_hold_h);
 245                 if (ret) {
 246                         printf("SEC Firmware: Failed to initialize\n");
 247                         return ret;
 248                 }
 249         }
 250
 251         debug("SEC Firmware: Return from SEC Firmware: current_el = %d\n",
 252               current_el());
 253
 254         /*
 255          * The PE will be turned into target EL when returned from
 256          * SEC Firmware.
 257          */
 258         if (current_el() != SEC_FIRMWARE_TARGET_EL)
 259                 return -EACCES;
 260
 261         sec_firmware_addr |= SEC_FIRMWARE_RUNNING;
 262
 263         /* Set exception table and enable caches if it isn't EL3 */
 264         if (current_el() != 3) {
 265                 c_runtime_cpu_setup();
 266                 enable_caches();
 267         }
 268
 269         return 0;
 270 }