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/*
* Copyright © 2017-2022 The Crust Firmware Authors.
* SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0-only
*/
#include <delay.h>
#include <mmio.h>
#include <stdbool.h>
#include <stdint.h>
#include <util.h>
#include "css.h"
static const uint8_t power_switch_on_sequence[] = {
0xfe, 0xf8, 0xe0, 0xc0, 0x80, 0x00,
};
void
css_set_power_switch(uintptr_t addr, bool enable)
{
if (enable) {
/* Avoid killing the power if the switch is already enabled. */
if (mmio_read_32(addr) == 0x00)
return;
/* Allwinner's blob uses 10, 20, and 30μs delays, depending on
* the iteration. However, the same code works fine in ATF with
* no delays. The 10μs delay is here just to be extra safe. */
const uint8_t *sequence = power_switch_on_sequence;
do {
mmio_write_32(addr, *sequence);
udelay(10);
} while (*sequence++ != 0x00);
} else {
mmio_write_32(addr, 0xff);
}
}
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