nuttx/configs/sam4s-xplained/src/sam_sram.c

135 lines
4.7 KiB
C
Raw Normal View History

2013-06-26 18:57:25 +02:00
/************************************************************************************
* configs/sam4s-xplained/src/sam_sram.c
*
* Copyright (C) 2013 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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.
*
************************************************************************************/
/************************************************************************************
* Included Files
************************************************************************************/
#include <nuttx/config.h>
#include <debug.h>
#include "up_arch.h"
#include "sam4s_periphclks.h"
#include "chip/sam3u_smc.h"
2013-06-26 18:57:25 +02:00
#include "sam4s-xplained.h"
#ifdef CONFIG_ARCH_EXTSRAM0
/************************************************************************************
* Pre-processor Definitions
************************************************************************************/
#define NPINS (3+8+19+1)
/************************************************************************************
* Private Data
************************************************************************************/
static const gpio_pinset_t g_srampins[NPINS] =
{
GPIO_SMC_NCS0, GPIO_SMC_NRD, GPIO_SMC_NWE,
GPIO_SMC_D0, GPIO_SMC_D1, GPIO_SMC_D2, GPIO_SMC_D3,
GPIO_SMC_D4, GPIO_SMC_D5, GPIO_SMC_D6, GPIO_SMC_D7,
GPIO_SMC_A0, GPIO_SMC_A1, GPIO_SMC_A2, GPIO_SMC_A3,
GPIO_SMC_A4, GPIO_SMC_A5, GPIO_SMC_A6, GPIO_SMC_A7,
GPIO_SMC_A8, GPIO_SMC_A9, GPIO_SMC_A10, GPIO_SMC_A11,
GPIO_SMC_A12, GPIO_SMC_A13, GPIO_SMC_A14, GPIO_SMC_A15,
GPIO_SMC_A16, GPIO_SMC_A17, GPIO_SMC_A18,
GPIO_EBI_NLB
};
/************************************************************************************
* Private Functions
************************************************************************************/
/************************************************************************************
* Public Functions
************************************************************************************/
/************************************************************************************
* Name: sam_sram_initialize
*
* Description:
* Configure and enable SRAM on board the SAM4S Xplained
*
************************************************************************************/
void sam_sram_initialize(void)
{
int i;
/* Configure GPIO pins (leaving SRAM in the disabled state) */
for (i = 0; i < NPINS; i++)
{
sam_configgpio(g_srampins[i]);
}
/* Enable PMC clock to the SMC */
sam_smc_enableclk();
/* Configure SMC setup timing */
putreg32(SMCCS_SETUP_NWESETUP(1) | SMCCS_SETUP_NCSWRSETUP(1) |
SMCCS_SETUP_NRDSETUP(1) | SMCCS_SETUP_NCSRDSETUP(1),
SAM_SMCCS0_SETUP);
/* Configure the SMC pulse timing */
putreg32(SMCCS_PULSE_NWEPULSE(6) | SMCCS_PULSE_NCSWRPULSE(6) |
SMCCS_PULSE_NRDPULSE(6) | SMCCS_PULSE_NCSRDPULSE(6),
SAM_SMCCS0_PULSE);
/* Configure the SMC cycle timing */
putreg32(SMCCS_CYCLE_NWECYCLE(7) | SMCCS_CYCLE_NRDCYCLE(7),
SAM_SMCCS0_CYCLE);
/* Configure the SMC mode */
putreg32(SMCCS_MODE_READMODE | SMCCS_MODE_WRITEMODE, SAM_SMCCS0_MODE);
/* Enable SRAM access (active low) */
sam_gpiowrite(GPIO_EBI_NLB, false);
}
#endif /* CONFIG_ARCH_EXTSRAM0 */