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Remove redundant RAM address and data scrambling

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The RAM address and data scrambling API was called twice, once before filling
RAM with random values, and once after. Since moving to a significantly
better PRNG (xorwow) this is now deemed unnecessary. See issue #225.

This changes both FPGA and firmware hashes.
This commit is contained in:
dehanj 2024-06-12 15:12:09 +02:00
parent 92712a11bf
commit b4c525695a
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GPG key ID: 3707A9DBF4BB8F1A
3 changed files with 3 additions and 8 deletions
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7
hw/application_fpga/fw/tk1/main.c
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@ -377,10 +377,6 @@ static void scramble_ram(void)
{
uint32_t *ram = (uint32_t *)(TK1_RAM_BASE);
// Set RAM address and data scrambling values
*ram_rand = rnd_word();
*ram_scramble = rnd_word();
// Fill RAM with random data
// Get random state and accumulator seeds.
uint32_t data_state = rnd_word();
@ -391,8 +387,7 @@ static void scramble_ram(void)
ram[w] = data_state;
}
// Set new address and RAM scrambling values,
// for all use of RAM by app.
// Set RAM address and data scrambling parameters
*ram_rand = rnd_word();
*ram_scramble = rnd_word();
}