/****************************************************************************
* configs/sama5d3x-ek/src/sam_norflash.c
*
* Copyright (C) 2013 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Most of this file derives from Atmel sample code for the SAMA5D3x-EK
* board. That sample code has licensing that is compatible with the NuttX
* modified BSD license:
*
* Copyright (c) 2012, Atmel Corporation
* All rights reserved.
*
* 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 Atmel 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <debug.h>
#include "up_arch.h"
#include "sam_periphclks.h"
#include "chip/sam_hsmc.h"
#include "sama5d3x-ek.h"
#ifdef CONFIG_SAMA5_BOOT_CS0FLASH
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* 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.
*
****************************************************************************/
void board_norflash_config(void)
{
uint32_t regval;
/* Make sure that the SMC peripheral is enabled (But of course it is... we
* are executing from NOR FLASH now).
*/
sam_hsmc_enableclk();
/* The SAMA5D3x-EK has 118MB of 16-bit NOR FLASH at CS0. The NOR FLASH
* has already been configured by the first level ROM bootloader... we
* simply need to modify the timing here.
*/
regval = HSMC_SETUP_NWE_SETUP(1) | HSMC_SETUP_NCS_WRSETUP(0) |
HSMC_SETUP_NRD_SETUP(2) | HSMC_SETUP_NCS_RDSETUP(0);
putreg32(regval, SAM_HSMC_SETUP(HSMC_CS0));
regval = HSMC_PULSE_NWE_PULSE(10) | HSMC_PULSE_NCS_WRPULSE(10) |
HSMC_PULSE_NRD_PULSE(11) | HSMC_PULSE_NCS_RDPULSE(11);
putreg32(regval, SAM_HSMC_PULSE(HSMC_CS0));
regval = HSMC_CYCLE_NWE_CYCLE(11) | HSMC_CYCLE_NRD_CYCLE(14);
putreg32(regval, SAM_HSMC_CYCLE(HSMC_CS0));
regval = HSMC_TIMINGS_TCLR(0) | HSMC_TIMINGS_TADL(0) |
HSMC_TIMINGS_TAR(0) | HSMC_TIMINGS_TRR(0) |
HSMC_TIMINGS_TWB(0) | HSMC_TIMINGS_RBNSEL(0);
putreg32(regval, SAM_HSMC_TIMINGS(HSMC_CS0));
regval = HSMC_MODE_READMODE | HSMC_MODE_WRITEMODE |
HSMC_MODE_EXNWMODE_DISABLED | HSMC_MODE_BIT_16 |
HSMC_MODE_TDFCYCLES(1);
putreg32(regval, SAM_HSMC_MODE(HSMC_CS0));
}
#endif /* CONFIG_SAMA5_BOOT_CS0FLASH */
