rockbox/firmware/target/mips/ingenic_x1000/boot-x1000.h

/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2021 Aidan MacDonald
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/

#ifndef __BOOT_X1000_H__
#define __BOOT_X1000_H__

#include "x1000/cpm.h"
#include <stdbool.h>
#include <stdint.h>
#include <stddef.h>

enum {
    BOOT_OPTION_ROCKBOX = 0,
    BOOT_OPTION_OFW_PLAYER,
    BOOT_OPTION_OFW_RECOVERY,
};

enum {
    /* 3 bits to store the boot option selected by the SPL */
    BOOT_OPTION_MASK  = 0x7,
    BOOT_OPTION_SHIFT = 0,

    /* Set after running clk_init() and setting up system clocks */
    BOOT_FLAG_CLK_INIT = (1 << 31),

    /* Set by the SPL if it was loaded over USB boot */
    BOOT_FLAG_USB_BOOT = (1 << 30),
};

void x1000_boot_rockbox(const void* source, size_t length)
    __attribute__((section(".icode")));

/* Note: these functions are inlined to minimize SPL code size.
 * They are private to the X1000 early boot code anyway... */

static inline void cpm_scratch_set(uint32_t value)
{
    /* TODO: see if this holds its state over a WDT reset */
    REG_CPM_SCRATCH_PROT = 0x5a5a;
    REG_CPM_SCRATCH = value;
    REG_CPM_SCRATCH_PROT = 0xa5a5;
}

static inline void init_boot_flags(void)
{
    cpm_scratch_set(0);
}

static inline bool get_boot_flag(uint32_t bit)
{
    return (REG_CPM_SCRATCH & bit) != 0;
}

static inline void set_boot_flag(uint32_t bit)
{
    cpm_scratch_set(REG_CPM_SCRATCH | bit);
}

static inline void clr_boot_flag(uint32_t bit)
{
    cpm_scratch_set(REG_CPM_SCRATCH & ~bit);
}

static inline void set_boot_option(int opt)
{
    uint32_t r = REG_CPM_SCRATCH;
    r &= ~(BOOT_OPTION_MASK << BOOT_OPTION_SHIFT);
    r |= (opt & BOOT_OPTION_MASK) << BOOT_OPTION_SHIFT;
    cpm_scratch_set(r);
}

static inline int get_boot_option(void)
{
    uint32_t r = REG_CPM_SCRATCH;
    return (r >> BOOT_OPTION_SHIFT) & BOOT_OPTION_MASK;
}

#endif /* __BOOT_X1000_H__ */