rtems/bsps/riscv/shared/start/bspgetworkarea.c

/* SPDX-License-Identifier: BSD-2-Clause */

/**
 * @file
 *
 * @brief BSP specific initialization support routines
 *
 */

/*
 * COPYRIGHT (c) 1989-2020.
 * On-Line Applications Research Corporation (OAR).
 * Cobham Gaisler AB.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <bsp.h>
#include <bsp/fdt.h>

#include <rtems/sysinit.h>

#include <libfdt.h>

/*
 *  These are provided by the linkcmds for ALL of the BSPs which use this file.
 */
extern char WorkAreaBase[];
extern char RamEnd[];

static Memory_Area _Memory_Areas[ 1 ];

static const char memory_path[] = "/memory";

static void* get_end_of_memory_from_fdt(void)
{
  const void *fdt;
  const void *val;
  int node;
  int parent;
  int ac;
  int sc;
  int len;
  uintptr_t start;
  uintptr_t size;

  fdt = bsp_fdt_get();

  node = fdt_path_offset_namelen(
    fdt,
    memory_path,
    (int) sizeof(memory_path) - 1
  );

  if (node < 0) {
    return NULL;
  }

  parent = fdt_parent_offset(fdt, node);
  if (parent < 0) {
    return NULL;
  }

  ac = fdt_address_cells(fdt, parent);
  if (ac != 1 && ac != 2) {
    return NULL;
  }

  sc = fdt_size_cells(fdt, parent);
  if (sc != 1 && sc != 2) {
    return NULL;
  }

  if (sc > ac) {
    return NULL;
  }

  val = fdt_getprop(fdt, node, "reg", &len);
  if (len < sc + ac) {
    return NULL;
  }

  if (ac == 1) {
    start = fdt32_to_cpu(((fdt32_t *)val)[0]);
    size = fdt32_to_cpu(((fdt32_t *)val)[1]);
  }

  if (ac == 2) {
    start = fdt64_to_cpu(((fdt64_t *)val)[0]);

    if (sc == 1)
      size = fdt32_to_cpu(((fdt32_t *)(val+8))[0]);
    else
      size = fdt64_to_cpu(((fdt64_t *)val)[1]);
  }

  return (void*) (start + size);
}

static void bsp_memory_initialize( void )
{
  void *end;

  /* get end of memory from the "/memory" node in the fdt */
  end = get_end_of_memory_from_fdt();
  if (end == NULL) {
    /* fall back to linker symbol if "/memory" node not found or invalid */
    end = RamEnd;
  }
  _Memory_Initialize( &_Memory_Areas[ 0 ], WorkAreaBase, end );
}

RTEMS_SYSINIT_ITEM(
  bsp_memory_initialize,
  RTEMS_SYSINIT_MEMORY,
  RTEMS_SYSINIT_ORDER_MIDDLE
);

static const Memory_Information _Memory_Information =
  MEMORY_INFORMATION_INITIALIZER( _Memory_Areas );

const Memory_Information *_Memory_Get( void )
{
  return &_Memory_Information;
}