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mimxrt/mphalport: Fix strict aliasing error with unique id.

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This commit is contained in:
Jared Hancock 2022-05-30 11:05:39 -04:00 committed by Damien George
parent 6bda80d811
commit 2f4aca0381
1 changed files with 6 additions and 6 deletions
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12
ports/mimxrt/mphalport.c
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@ -140,8 +140,8 @@ uint64_t mp_hal_time_ns(void) {
// MAC address
void mp_hal_get_unique_id(uint8_t id[]) {
*(uint32_t *)&id[0] = OCOTP->CFG0;
*(uint32_t *)&id[4] = OCOTP->CFG1;
*(uint32_t *)id = OCOTP->CFG0;
*(uint32_t *)(id + 4) = OCOTP->CFG1;
}
// Generate a random locally administered MAC address (LAA)
@ -150,12 +150,12 @@ void mp_hal_generate_laa_mac(int idx, uint8_t buf[6]) {
unsigned char id[8];
mp_hal_get_unique_id(id);
uint32_t pt1 = *(uint32_t *)&id[0];
uint32_t pt2 = *(uint32_t *)&id[4];
uint32_t *pt1 = (uint32_t *)id;
uint32_t *pt2 = (uint32_t *)(id + 4);
buf[0] = 0x02; // Locally Administered MAC
*(uint32_t *)&buf[1] = pt1 ^ (pt1 >> 8);
*(uint16_t *)&buf[4] = (uint16_t)(pt2 ^ pt2 >> 16);
*(uint32_t *)&buf[1] = *pt1 ^ (*pt1 >> 8);
*(uint16_t *)&buf[4] = (uint16_t)(*pt2 ^ *pt2 >> 16);
buf[5] ^= (uint8_t)idx;
}