rtems/bsps/arm/raspberrypi/start/bspstarthooks.c

/**
 * @file
 *
 * @ingroup arm_start
 *
 * @brief Rasberry Pi startup code.
 */

/*
 * Copyright (c) 2013. Hesham AL-Matary
 * Copyright (c) 2013 by Alan Cudmore
 * based on work by:
 * Copyright (c) 2009
 * embedded brains GmbH
 * Obere Lagerstr. 30
 * D-82178 Puchheim
 * Germany
 * <rtems@embedded-brains.de>
 *
 * The license and distribution terms for this file may be
 * found in the file LICENSE in this distribution or at
 * http://www.rtems.org/license/LICENSE
 */

#include <bspopts.h>
#include <bsp/start.h>
#include <bsp/raspberrypi.h>
#include <libcpu/arm-cp15.h>
#include <bsp.h>
#include <bsp/bootcard.h>
#include <bsp/linker-symbols.h>
#include <bsp/arm-cp15-start.h>

#ifdef RTEMS_SMP
#include <rtems/score/smp.h>
#endif

#if defined(HAS_UBOOT) && !defined(BSP_DISABLE_UBOOT_WORK_AREA_CONFIG)
  #define USE_UBOOT
#endif

#ifdef USE_UBOOT
  #include <bsp/u-boot.h>
#else
  #include <bsp/vc.h>
#endif

BSP_START_DATA_SECTION static arm_cp15_start_section_config
raspberrypi_mmu_config_table[] = {
  ARMV7_CP15_START_DEFAULT_SECTIONS,
  {
    .begin = RPI_PERIPHERAL_BASE,
    .end =   RPI_PERIPHERAL_BASE + RPI_PERIPHERAL_SIZE,
    .flags = ARMV7_MMU_DEVICE
  }
#if (BSP_IS_RPI2 == 1)
  /* Core local peripherals area - timer, mailboxes */
  , {
    .begin = BCM2836_CORE_LOCAL_PERIPH_BASE,
    .end =   BCM2836_CORE_LOCAL_PERIPH_BASE + BCM2836_CORE_LOCAL_PERIPH_SIZE,
    .flags = ARMV7_MMU_DEVICE
  }
#endif
};

void BSP_START_TEXT_SECTION bsp_start_hook_0(void)
{
  uint32_t sctlr_val;
#ifdef RTEMS_SMP
  uint32_t cpu_index_self = _SMP_Get_current_processor();
#endif /* RTEMS_SMP */

  sctlr_val = arm_cp15_get_control();

  /*
   * Current U-boot loader seems to start kernel image
   * with I and D caches on and MMU enabled.
   * If RTEMS application image finds that cache is on
   * during startup then disable caches.
   */
  if (sctlr_val & (ARM_CP15_CTRL_I | ARM_CP15_CTRL_C | ARM_CP15_CTRL_M)) {
    if (sctlr_val & (ARM_CP15_CTRL_C | ARM_CP15_CTRL_M)) {
      /*
       * If the data cache is on then ensure that it is clean
       * before switching off to be extra carefull.
       */
#ifdef RTEMS_SMP
      if (cpu_index_self != 0) {
        arm_cp15_data_cache_clean_level(0);
        arm_cp15_cache_invalidate_level(0, 0);
      } else
#endif /* RTEMS_SMP */
      {
        rtems_cache_flush_entire_data();
        rtems_cache_invalidate_entire_data();
      }
    }
    arm_cp15_flush_prefetch_buffer();
    sctlr_val &= ~(ARM_CP15_CTRL_I | ARM_CP15_CTRL_C | ARM_CP15_CTRL_M | ARM_CP15_CTRL_A);
    arm_cp15_set_control(sctlr_val);
  }
#ifdef RTEMS_SMP
  if (cpu_index_self != 0) {
    arm_cp15_cache_invalidate_level(0, 0);
  } else
#endif /* RTEMS_SMP */
  {
    rtems_cache_invalidate_entire_data();
  }
  rtems_cache_invalidate_entire_instruction();
  arm_cp15_branch_predictor_invalidate_all();
  arm_cp15_tlb_invalidate();
  arm_cp15_flush_prefetch_buffer();

  /* Clear Translation Table Base Control Register */
  arm_cp15_set_translation_table_base_control_register(0);

  /* Clear Secure or Non-secure Vector Base Address Register */
  arm_cp15_set_vector_base_address(bsp_vector_table_begin);

#ifdef RTEMS_SMP
  if (cpu_index_self == 0) {
    rpi_ipi_initialize();
  } else {
    rpi_start_rtems_on_secondary_processor();
  }
#endif
}

BSP_START_TEXT_SECTION static uintptr_t raspberrypi_get_ram_end(void)
{
  uintptr_t ram_end;

#ifdef USE_UBOOT
  ram_end = (uintptr_t) bsp_uboot_board_info.bi_memstart +
                        bsp_uboot_board_info.bi_memsize;
#else
  bcm2835_get_arm_memory_entries spec;

  if (bcm2835_mailbox_get_arm_memory( &spec ) >= 0) {
    ram_end = spec.base + spec.size;
  } else {
    /* Use the workspace end from the linker command file for fallback. */
    ram_end = (uintptr_t) bsp_section_work_end;
  }
#endif

  return ram_end;
}

BSP_START_TEXT_SECTION static void bsp_memory_management_initialize(void)
{
  uintptr_t ram_end = raspberrypi_get_ram_end();
  uint32_t ctrl = arm_cp15_get_control();

  ctrl |= ARM_CP15_CTRL_AFE | ARM_CP15_CTRL_S | ARM_CP15_CTRL_XP;

  raspberrypi_mmu_config_table[ARMV7_CP15_START_WORKSPACE_ENTRY_INDEX].end =
    ram_end;

  arm_cp15_start_setup_translation_table_and_enable_mmu_and_cache(
    ctrl,
    (uint32_t *) bsp_translation_table_base,
    ARM_MMU_DEFAULT_CLIENT_DOMAIN,
    &raspberrypi_mmu_config_table[0],
    RTEMS_ARRAY_SIZE(raspberrypi_mmu_config_table)
  );
}

void BSP_START_TEXT_SECTION bsp_start_hook_1(void)
{
  bsp_start_copy_sections();
  bsp_memory_management_initialize();
  bsp_start_clear_bss();

  rpi_video_init();
}

void bsp_work_area_initialize(void)
{
  uintptr_t begin;
  uintptr_t end;

  begin = raspberrypi_mmu_config_table[ARMV7_CP15_START_WORKSPACE_ENTRY_INDEX]
          .begin;
  end = raspberrypi_mmu_config_table[ARMV7_CP15_START_WORKSPACE_ENTRY_INDEX]
        .end;

  bsp_work_area_initialize_default((void *) begin, end - begin);
}