/**************************************************************************** * arch/arm/src/sama5/sam_clockconfig.h * * Copyright (C) 2013-2014 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * 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. * ****************************************************************************/ #ifndef __ARCH_ARM_SRC_SAMA5_SAM_CLOCKCONFIG_H #define __ARCH_ARM_SRC_SAMA5_SAM_CLOCKCONFIG_H /**************************************************************************** * Included Files ****************************************************************************/ #include #include "up_internal.h" /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /**************************************************************************** * Public Types ****************************************************************************/ /**************************************************************************** * Inline Functions ****************************************************************************/ #ifndef __ASSEMBLY__ /**************************************************************************** * Public Data ****************************************************************************/ #undef EXTERN #if defined(__cplusplus) #define EXTERN extern "C" extern "C" { #else #define EXTERN extern #endif /**************************************************************************** * Public Function Prototypes ****************************************************************************/ /**************************************************************************** * Name: sam_clockconfig * * Description: * Called to initialize the SAM3/4. This does whatever setup is needed to * put the SoC in a usable state. This includes the initialization of * clocking using the settings in board.h. * ****************************************************************************/ void __ramfunc__ sam_clockconfig(void); /**************************************************************************** * Name: board_norflash_config * * Description: * If CONFIG_SAMA5_BOOT_CS0FLASH, then the system is boot directly off * CS0 NOR FLASH. In this case, we assume that we get here from the * primary boot loader under these conditions: * * "If BMS signal is tied to 0, BMS_BIT is read at 1. The ROM Code * allows execution of the code contained into the memory connected to * Chip Select 0 of the External Bus Interface. * * "To achieve that, the following sequence is preformed by the ROM * Code: * * - The main clock is the on-chip 12 MHz RC oscillator, * - The Static Memory Controller is configured with timing allowing * code execution inCS0 external memory at 12 MHz * - AXI matrix is configured to remap EBI CS0 address at 0x0 * - 0x0 is loaded in the Program Counter register * * "The user software in the external memory must perform the next * operation in order to complete the clocks and SMC timings * configuration to run at a higher clock frequency: * * - Enable the 32768 Hz oscillator if best accuracy is needed * - Reprogram the SMC setup, cycle, hold, mode timing registers * for EBI CS0, to adapt them to the new clock * - Program the PMC (Main Oscillator Enable or Bypass mode) * - Program and Start the PLL * - Switch the system clock to the new value" * * This function provides the board-specific implementation of the logic * to reprogram the SMC. * ****************************************************************************/ #ifdef CONFIG_SAMA5_BOOT_CS0FLASH void board_norflash_config(void); #endif #undef EXTERN #if defined(__cplusplus) } #endif #endif /* __ASSEMBLY__ */ #endif /* __ARCH_ARM_SRC_SAMA5_SAM_CLOCKCONFIG_H */