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bootloader_support: read random from register

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morris
2020-02-26 18:40:21 +08:00
parent f735b8891e
commit ddcba3d574
1 changed files with 0 additions and 7 deletions
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7
components/bootloader_support/src/bootloader_random.c
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@@ -40,9 +40,7 @@ void bootloader_fill_random(void *buffer, size_t length)
{ {
uint8_t *buffer_bytes = (uint8_t *)buffer; uint8_t *buffer_bytes = (uint8_t *)buffer;
uint32_t random; uint32_t random;
#if CONFIG_IDF_TARGET_ESP32
uint32_t start, now; uint32_t start, now;
#endif
assert(buffer != NULL); assert(buffer != NULL);
@@ -55,17 +53,12 @@ void bootloader_fill_random(void *buffer, size_t length)
as-is, we repeatedly read the RNG register and XOR all as-is, we repeatedly read the RNG register and XOR all
values. values.
*/ */
#if CONFIG_IDF_TARGET_ESP32
random = REG_READ(WDEV_RND_REG); random = REG_READ(WDEV_RND_REG);
RSR(CCOUNT, start); RSR(CCOUNT, start);
do { do {
random ^= REG_READ(WDEV_RND_REG); random ^= REG_READ(WDEV_RND_REG);
RSR(CCOUNT, now); RSR(CCOUNT, now);
} while (now - start < 80 * 32 * 2); /* extra factor of 2 is precautionary */ } while (now - start < 80 * 32 * 2); /* extra factor of 2 is precautionary */
#elif CONFIG_IDF_TARGET_ESP32S2
// ToDo: Get random from register
random = 12345678;
#endif
} }
buffer_bytes[i] = random >> ((i % 4) * 8); buffer_bytes[i] = random >> ((i % 4) * 8);
} }