/*
* novena-eim.c
* ------------
* This module contains the userland magic to set up and use the EIM bus.
*
*
* Author: Pavel Shatov
* Copyright (c) 2014-2015, NORDUnet A/S All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - 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.
*
* - Neither the name of the NORDUnet 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
* HOLDER 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.
*/
//------------------------------------------------------------------------------
// Headers
//------------------------------------------------------------------------------
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdint.h>
#include <sys/mman.h>
#include "novena-eim.h"
//------------------------------------------------------------------------------
// Defines
//------------------------------------------------------------------------------
#define MEMORY_DEVICE "/dev/mem"
#define IOMUXC_MUX_MODE_ALT0 0 // 000
#define IOMUXC_PAD_CTL_SRE_FAST 1 // 1
#define IOMUXC_PAD_CTL_DSE_33_OHM 7 // 111
#define IOMUXC_PAD_CTL_SPEED_MEDIUM_10 2 // 10
#define IOMUXC_PAD_CTL_ODE_DISABLED 0 // 0
#define IOMUXC_PAD_CTL_PKE_DISABLED 0 // 0
#define IOMUXC_PAD_CTL_PUE_PULL 1 // 1
#define IOMUXC_PAD_CTL_PUS_100K_OHM_PU 2 // 10
#define IOMUXC_PAD_CTL_HYS_DISABLED 0 // 0
#define CCM_CGR_OFF 0 // 00
#define CCM_CGR_ON_EXCEPT_STOP 3 // 11
//------------------------------------------------------------------------------
// CPU Registers
//------------------------------------------------------------------------------
enum IMX6DQ_REGISTER_OFFSET
{
IOMUXC_SW_MUX_CTL_PAD_EIM_CS0_B = 0x020E00F8,
IOMUXC_SW_MUX_CTL_PAD_EIM_OE_B = 0x020E0100,
IOMUXC_SW_MUX_CTL_PAD_EIM_RW = 0x020E0104,
IOMUXC_SW_MUX_CTL_PAD_EIM_LBA_B = 0x020E0108,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD00 = 0x020E0114,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD01 = 0x020E0118,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD02 = 0x020E011C,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD03 = 0x020E0120,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD04 = 0x020E0124,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD05 = 0x020E0128,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD06 = 0x020E012C,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD07 = 0x020E0130,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD08 = 0x020E0134,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD09 = 0x020E0138,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD10 = 0x020E013C,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD11 = 0x020E0140,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD12 = 0x020E0144,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD13 = 0x020E0148,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD14 = 0x020E014C,
IOMUXC_SW_MUX_CTL_PAD_EIM_AD15 = 0x020E0150,
IOMUXC_SW_MUX_CTL_PAD_EIM_WAIT_B = 0x020E0154,
IOMUXC_SW_MUX_CTL_PAD_EIM_BCLK = 0x020E0158,
IOMUXC_SW_PAD_CTL_PAD_EIM_CS0_B = 0x020E040C,
IOMUXC_SW_PAD_CTL_PAD_EIM_OE_B = 0x020E0414,
IOMUXC_SW_PAD_CTL_PAD_EIM_RW = 0x020E0418,
IOMUXC_SW_PAD_CTL_PAD_EIM_LBA_B = 0x020E041C,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD00 = 0x020E0428,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD01 = 0x020E042C,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD02 = 0x020E0430,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD03 = 0x020E0434,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD04 = 0x020E0438,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD05 = 0x020E043C,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD06 = 0x020E0440,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD07 = 0x020E0444,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD08 = 0x020E0448,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD09 = 0x020E044C,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD10 = 0x020E0450,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD11 = 0x020E0454,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD12 = 0x020E0458,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD13 = 0x020E045C,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD14 = 0x020E0460,
IOMUXC_SW_PAD_CTL_PAD_EIM_AD15 = 0x020E0464,
IOMUXC_SW_PAD_CTL_PAD_EIM_WAIT_B = 0x020E0468,
IOMUXC_SW_PAD_CTL_PAD_EIM_BCLK = 0x020E046C,
CCM_CCGR6 = 0x020C4080,
EIM_CS0GCR1 = 0x021B8000,
EIM_CS0GCR2 = 0x021B8004,
EIM_CS0RCR1 = 0x021B8008,
EIM_CS0RCR2 = 0x021B800C,
EIM_CS0WCR1 = 0x021B8010,
EIM_CS0WCR2 = 0x021B8014,
EIM_WCR = 0x021B8090,
EIM_WIAR = 0x021B8094,
EIM_EAR = 0x021B8098,
};
//------------------------------------------------------------------------------
// Structures
//------------------------------------------------------------------------------
struct IOMUXC_SW_MUX_CTL_PAD_EIM
{
unsigned int mux_mode : 3;
unsigned int reserved_3 : 1;
unsigned int sion : 1;
unsigned int reserved_31_5 : 27;
};
struct IOMUXC_SW_PAD_CTL_PAD_EIM
{
unsigned int sre : 1;
unsigned int reserved_2_1 : 2;
unsigned int dse : 3;
unsigned int speed : 2;
unsigned int reserved_10_8 : 3;
unsigned int ode : 1;
unsigned int pke : 1;
unsigned int pue : 1;
unsigned int pus : 2;
unsigned int hys : 1;
unsigned int reserved_31_17 : 15;
};
struct CCM_CCGR6
{
unsigned int cg0_usboh3 : 2;
unsigned int cg1_usdhc1 : 2;
unsigned int cg2_usdhc2 : 2;
unsigned int cg3_usdhc3 : 2;
unsigned int cg3_usdhc4 : 2;
unsigned int cg5_eim_slow : 2;
unsigned int cg6_vdoaxiclk : 2;
unsigned int cg7_vpu : 2;
unsigned int cg8_reserved : 2;
unsigned int cg9_reserved : 2;
unsigned int cg10_reserved : 2;
unsigned int cg11_reserved : 2;
unsigned int cg12_reserved : 2;
unsigned int cg13_reserved : 2;
unsigned int cg14_reserved : 2;
unsigned int cg15_reserved : 2;
};
struct EIM_CS_GCR1
{
unsigned int csen : 1;
unsigned int swr : 1;
unsigned int srd : 1;
unsigned int mum : 1;
unsigned int wfl : 1;
unsigned int rfl : 1;
unsigned int cre : 1;
unsigned int crep : 1;
unsigned int bl : 3;
unsigned int wc : 1;
unsigned int bcd : 2;
unsigned int bcs : 2;
unsigned int dsz : 3;
unsigned int sp : 1;
unsigned int csrec : 3;
unsigned int aus : 1;
unsigned int gbc : 3;
unsigned int wp : 1;
unsigned int psz : 4;
};
struct EIM_CS_GCR2
{
unsigned int adh : 2;
unsigned int reserved_3_2 : 2;
unsigned int daps : 4;
unsigned int dae : 1;
unsigned int dap : 1;
unsigned int reserved_11_10 : 2;
unsigned int mux16_byp_grant : 1;
unsigned int reserved_31_13 : 19;
};
struct EIM_CS_RCR1
{
unsigned int rcsn : 3;
unsigned int reserved_3 : 1;
unsigned int rcsa : 3;
unsigned int reserved_7 : 1;
unsigned int oen : 3;
unsigned int reserved_11 : 1;
unsigned int oea : 3;
unsigned int reserved_15 : 1;
unsigned int radvn : 3;
unsigned int ral : 1;
unsigned int radva : 3;
unsigned int reserved_23 : 1;
unsigned int rwsc : 6;
unsigned int reserved_31_30 : 2;
};
struct EIM_CS_RCR2
{
unsigned int rben : 3;
unsigned int rbe : 1;
unsigned int rbea : 3;
unsigned int reserved_7 : 1;
unsigned int rl : 2;
unsigned int reserved_11_10 : 2;
unsigned int pat : 3;
unsigned int apr : 1;
unsigned int reserved_31_16 : 16;
};
struct EIM_CS_WCR1
{
unsigned int wcsn : 3;
unsigned int wcsa : 3;
unsigned int wen : 3;
unsigned int wea : 3;
unsigned int wben : 3;
unsigned int wbea : 3;
unsigned int wadvn : 3;
unsigned int wadva : 3;
unsigned int wwsc : 6;
unsigned int wbed : 1;
unsigned int wal : 1;
};
struct EIM_CS_WCR2
{
unsigned int wbcdd : 1;
unsigned int reserved_31_1 : 31;
};
struct EIM_WCR
{
unsigned int bcm : 1;
unsigned int gbcd : 2;
unsigned int reserved_3 : 1;
unsigned int inten : 1;
unsigned int intpol : 1;
unsigned int reserved_7_6 : 2;
unsigned int wdog_en : 1;
unsigned int wdog_limit : 2;
unsigned int reserved_31_11 : 21;
};
struct EIM_WIAR
{
unsigned int ips_req : 1;
unsigned int ips_ack : 1;
unsigned int irq : 1;
unsigned int errst : 1;
unsigned int aclk_en : 1;
unsigned int reserved_31_5 : 27;
};
struct EIM_EAR
{
unsigned int error_addr : 32;
};
//------------------------------------------------------------------------------
// Variables
//------------------------------------------------------------------------------
static long mem_page_size = 0;
static int mem_dev_fd = -1;
static void * mem_map_ptr = MAP_FAILED;
static off_t mem_base_addr = 0;
//------------------------------------------------------------------------------
// Prototypes
//------------------------------------------------------------------------------
static void _eim_setup_iomuxc (void);
static void _eim_setup_ccm (void);
static void _eim_setup_eim (void);
static void _eim_cleanup (void);
static off_t _eim_calc_offset (off_t);
static void _eim_remap_mem (off_t);
//------------------------------------------------------------------------------
// Set up EIM bus. Returns 0 on success, -1 on failure.
//------------------------------------------------------------------------------
int eim_setup(void)
{
// register cleanup function
if (atexit(_eim_cleanup) != 0) {
fprintf(stderr, "ERROR: atexit() failed.\n");
return -1;
}
// determine memory page size to use in mmap()
mem_page_size = sysconf(_SC_PAGESIZE);
if (mem_page_size < 1) {
fprintf(stderr, "ERROR: sysconf(_SC_PAGESIZE) == %ld\n", mem_page_size);
return -1;
}
// try to open memory device
mem_dev_fd = open(MEMORY_DEVICE, O_RDWR | O_SYNC);
if (mem_dev_fd == -1) {
fprintf(stderr, "ERROR: open(%s) failed.\n", MEMORY_DEVICE);
return -1;
}
// configure IOMUXC
_eim_setup_iomuxc();
// configure Clock Controller Module
_eim_setup_ccm();
/* We need to properly configure EIM mode and all the corresponding parameters.
* That's a lot of code, let's do it now.
*/
_eim_setup_eim();
// done
return 0;
}
//------------------------------------------------------------------------------
// Shut down EIM bus. This is called automatically on exit().
//------------------------------------------------------------------------------
static void _eim_cleanup(void)
{
// unmap memory if needed
if (mem_map_ptr != MAP_FAILED)
if (munmap(mem_map_ptr, mem_page_size) != 0)
fprintf(stderr, "WARNING: munmap() failed.\n");
// close memory device if needed
if (mem_dev_fd != -1)
if (close(mem_dev_fd) != 0)
fprintf(stderr, "WARNING: close() failed.\n");
}
//------------------------------------------------------------------------------
// Several blocks in the CPU have common pins. We use the I/O MUX Controller
// to configure what block will actually use I/O pins. We wait for the EIM
// module to be able to communicate with the on-board FPGA.
//------------------------------------------------------------------------------
static void _eim_setup_iomuxc(void)
{
// create structures
struct IOMUXC_SW_MUX_CTL_PAD_EIM reg_mux; // mux control register
struct IOMUXC_SW_PAD_CTL_PAD_EIM reg_pad; // pad control register
// setup mux control register
reg_mux.mux_mode = IOMUXC_MUX_MODE_ALT0; // ALT0 mode must be used for EIM
reg_mux.sion = 0; // forced input not needed
reg_mux.reserved_3 = 0; // must be 0
reg_mux.reserved_31_5 = 0; // must be 0
// setup pad control register
reg_pad.sre = IOMUXC_PAD_CTL_SRE_FAST; // fast slew rate
reg_pad.dse = IOMUXC_PAD_CTL_DSE_33_OHM; // highest drive strength
reg_pad.speed = IOMUXC_PAD_CTL_SPEED_MEDIUM_10; // medium speed
reg_pad.ode = IOMUXC_PAD_CTL_ODE_DISABLED; // open drain not needed
reg_pad.pke = IOMUXC_PAD_CTL_PKE_DISABLED; // neither pull nor keeper are needed
reg_pad.pue = IOMUXC_PAD_CTL_PUE_PULL; // doesn't matter actually, because PKE is disabled
reg_pad.pus = IOMUXC_PAD_CTL_PUS_100K_OHM_PU; // doesn't matter actually, because PKE is disabled
reg_pad.hys = IOMUXC_PAD_CTL_HYS_DISABLED; // use CMOS, not Schmitt trigger input
reg_pad.reserved_2_1 = 0; // must be 0
reg_pad.reserved_10_8 = 0; // must be 0
reg_pad.reserved_31_17 = 0; // must be 0
// all the pins must be configured to use the same ALT0 mode
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_CS0_B, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_OE_B, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_RW, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_LBA_B, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD00, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD01, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD02, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD03, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD04, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD05, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD06, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD07, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD08, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD09, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD10, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD11, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD12, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD13, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD14, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD15, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_WAIT_B, (uint32_t *)®_mux);
eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_BCLK, (uint32_t *)®_mux);
// we need to configure all the I/O pads too
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_CS0_B, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_OE_B, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_RW, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_LBA_B, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD00, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD01, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD02, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD03, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD04, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD05, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD06, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD07, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD08, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD09, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD10, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD11, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD12, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD13, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD14, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD15, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_WAIT_B, (uint32_t *)®_pad);
eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_BCLK, (uint32_t *)®_pad);
}
//------------------------------------------------------------------------------
// Configure Clock Controller Module to enable clocking of EIM block.
//------------------------------------------------------------------------------
static void _eim_setup_ccm(void)
{
// create structure
struct CCM_CCGR6 ccm_ccgr6;
// read register
eim_read_32(CCM_CCGR6, (uint32_t *)&ccm_ccgr6);
// modify register
ccm_ccgr6.cg0_usboh3 = CCM_CGR_ON_EXCEPT_STOP;
ccm_ccgr6.cg1_usdhc1 = CCM_CGR_OFF;
ccm_ccgr6.cg2_usdhc2 = CCM_CGR_ON_EXCEPT_STOP;
ccm_ccgr6.cg3_usdhc3 = CCM_CGR_ON_EXCEPT_STOP;
ccm_ccgr6.cg3_usdhc4 = CCM_CGR_OFF;
ccm_ccgr6.cg5_eim_slow = CCM_CGR_ON_EXCEPT_STOP;
ccm_ccgr6.cg6_vdoaxiclk = CCM_CGR_OFF;
ccm_ccgr6.cg7_vpu = CCM_CGR_OFF;
ccm_ccgr6.cg8_reserved = 0;
ccm_ccgr6.cg9_reserved = 0;
ccm_ccgr6.cg10_reserved = 0;
ccm_ccgr6.cg11_reserved = 0;
ccm_ccgr6.cg12_reserved = 0;
ccm_ccgr6.cg13_reserved = 0;
ccm_ccgr6.cg14_reserved = 0;
ccm_ccgr6.cg15_reserved = 0;
// write register
eim_write_32(CCM_CCGR6, (uint32_t *)&ccm_ccgr6);
}
//------------------------------------------------------------------------------
// Configure EIM mode and all the corresponding parameters. That's a lot of code.
//------------------------------------------------------------------------------
static void _eim_setup_eim(void)
{
// create structures
struct EIM_CS_GCR1 gcr1;
struct EIM_CS_GCR2 gcr2;
struct EIM_CS_RCR1 rcr1;
struct EIM_CS_RCR2 rcr2;
struct EIM_CS_WCR1 wcr1;
struct EIM_CS_WCR2 wcr2;
struct EIM_WCR wcr;
struct EIM_WIAR wiar;
struct EIM_EAR ear;
// read all the registers
eim_read_32(EIM_CS0GCR1, (uint32_t *)&gcr1);
eim_read_32(EIM_CS0GCR2, (uint32_t *)&gcr2);
eim_read_32(EIM_CS0RCR1, (uint32_t *)&rcr1);
eim_read_32(EIM_CS0RCR2, (uint32_t *)&rcr2);
eim_read_32(EIM_CS0WCR1, (uint32_t *)&wcr1);
eim_read_32(EIM_CS0WCR2, (uint32_t *)&wcr2);
eim_read_32(EIM_WCR, (uint32_t *)&wcr);
eim_read_32(EIM_WIAR, (uint32_t *)&wiar);
eim_read_32(EIM_EAR, (uint32_t *)&ear);
// manipulate registers as needed
gcr1.csen = 1; // chip select is enabled
gcr1.swr = 1; // write is sync
gcr1.srd = 1; // read is sync
gcr1.mum = 1; // address and data are multiplexed
gcr1.wfl = 0; // write latency is not fixed
gcr1.rfl = 0; // read latency is not fixed
gcr1.cre = 0; // CRE signal not needed
//gcr1.crep = x; // don't care, CRE not used
gcr1.bl = 4; // burst length
gcr1.wc = 0; // write is not continuous
gcr1.bcd = 3; // BCLK divisor is 3+1=4
gcr1.bcs = 1; // delay from ~CS to BCLK is 1 cycle
gcr1.dsz = 1; // 16 bits per databeat at DATA[15:0]
gcr1.sp = 0; // supervisor protection is disabled
gcr1.csrec = 1; // ~CS recovery is 1 cycle
gcr1.aus = 1; // address is not shifted
gcr1.gbc = 1; // ~CS gap is 1 cycle
gcr1.wp = 0; // write protection is not enabled
//gcr1.psz = x; // don't care, page mode is not used
gcr2.adh = 0; // address hold duration is 1 cycle
//gcr2.daps = x; // don't care, DTACK is not used
gcr2.dae = 0; // DTACK is not used
//gcr2.dap = x; // don't care, DTACK is not used
gcr2.mux16_byp_grant= 1; // enable grant mechanism
gcr2.reserved_3_2 = 0; // must be 0
gcr2.reserved_11_10 = 0; // must be 0
gcr2.reserved_31_13 = 0; // must be 0
//rcr1.rcsn = x; // don't care in sync mode
rcr1.rcsa = 0; // no delay for ~CS needed
//rcr1.oen = x; // don't care in sync mode
rcr1.oea = 0; // no delay for ~OE needed
rcr1.radvn = 0; // no delay for ~LBA needed
rcr1.ral = 0; // clear ~LBA when needed
rcr1.radva = 0; // no delay for ~LBA needed
rcr1.rwsc = 1; // one wait state
rcr1.reserved_3 = 0; // must be 0
rcr1.reserved_7 = 0; // must be 0
rcr1.reserved_11 = 0; // must be 0
rcr1.reserved_15 = 0; // must be 0
rcr1.reserved_23 = 0; // must be 0
rcr1.reserved_31_30 = 0; // must be 0
//rcr2.rben = x; // don't care in sync mode
rcr2.rbe = 0; // BE is disabled
//rcr2.rbea = x; // don't care when BE is not used
rcr2.rl = 0; // read latency is 0
//rcr2.pat = x; // don't care when page read is not used
rcr2.apr = 0; // page read mode is not used
rcr2.reserved_7 = 0; // must be 0
rcr2.reserved_11_10 = 0; // must be 0
rcr2.reserved_31_16 = 0; // must be 0
//wcr1.wcsn = x; // don't care in sync mode
wcr1.wcsa = 0; // no delay for ~CS needed
//wcr1.wen = x; // don't care in sync mode
wcr1.wea = 0; // no delay for ~WR_N needed
//wcr1.wben = x; // don't care in sync mode
//wcr1.wbea = x; // don't care in sync mode
wcr1.wadvn = 0; // no delay for ~LBA needed
wcr1.wadva = 0; // no delay for ~LBA needed
wcr1.wwsc = 1; // no wait state in needed
wcr1.wbed = 1; // BE is disabled
wcr1.wal = 0; // clear ~LBA when needed
wcr2.wbcdd = 0; // write clock division is not needed
wcr2.reserved_31_1 = 0; // must be 0
wcr.bcm = 0; // clock is only active during access
//wcr.gbcd = x; // don't care when BCM=0
wcr.inten = 0; // interrupt is not used
//wcr.intpol = x; // don't care when interrupt is not used
wcr.wdog_en = 1; // watchdog is enabled
wcr.wdog_limit = 00; // timeout is 128 BCLK cycles
wcr.reserved_3 = 0; // must be 0
wcr.reserved_7_6 = 0; // must be 0
wcr.reserved_31_11 = 0; // must be 0
wiar.ips_req = 0; // IPS not needed
wiar.ips_ack = 0; // IPS not needed
//wiar.irq = x; // don't touch
//wiar.errst = x; // don't touch
wiar.aclk_en = 1; // clock is enabled
wiar.reserved_31_5 = 0; // must be 0
//ear.error_addr = x; // read-only
// write modified registers
eim_write_32(EIM_CS0GCR1, (uint32_t *)&gcr1);
eim_write_32(EIM_CS0GCR2, (uint32_t *)&gcr2);
eim_write_32(EIM_CS0RCR1, (uint32_t *)&rcr1);
eim_write_32(EIM_CS0RCR2, (uint32_t *)&rcr2);
eim_write_32(EIM_CS0WCR1, (uint32_t *)&wcr1);
eim_write_32(EIM_CS0WCR2, (uint32_t *)&wcr2);
eim_write_32(EIM_WCR, (uint32_t *)&wcr);
eim_write_32(EIM_WIAR, (uint32_t *)&wiar);
/* eim_write_32(EIM_EAR, (uint32_t *)&ear);*/
}
//------------------------------------------------------------------------------
// Write a 32-bit word to EIM.
// If EIM is not set up correctly, this will abort with a bus error.
//------------------------------------------------------------------------------
void eim_write_32(off_t offset, uint32_t *pvalue)
{
// calculate memory offset
uint32_t *ptr = (uint32_t *)_eim_calc_offset(offset);
// write data to memory
memcpy(ptr, pvalue, sizeof(uint32_t));
}
//------------------------------------------------------------------------------
// Read a 32-bit word from EIM.
// If EIM is not set up correctly, this will abort with a bus error.
//------------------------------------------------------------------------------
void eim_read_32(off_t offset, uint32_t *pvalue)
{
// calculate memory offset
uint32_t *ptr = (uint32_t *)_eim_calc_offset(offset);
// read data from memory
memcpy(pvalue, ptr, sizeof(uint32_t));
}
//------------------------------------------------------------------------------
// Calculate an offset into the currently-mapped EIM page.
//------------------------------------------------------------------------------
static off_t _eim_calc_offset(off_t offset)
{
// make sure that memory is mapped
if (mem_map_ptr == MAP_FAILED)
_eim_remap_mem(offset);
// calculate starting and ending addresses of currently mapped page
off_t offset_low = mem_base_addr;
off_t offset_high = mem_base_addr + (mem_page_size - 1);
// check that offset is in currently mapped page, remap new page otherwise
if ((offset < offset_low) || (offset > offset_high))
_eim_remap_mem(offset);
// calculate pointer
return (off_t)mem_map_ptr + (offset - mem_base_addr);
}
//------------------------------------------------------------------------------
// Map in a new EIM page.
//------------------------------------------------------------------------------
static void _eim_remap_mem(off_t offset)
{
// unmap old memory page if needed
if (mem_map_ptr != MAP_FAILED) {
if (munmap(mem_map_ptr, mem_page_size) != 0) {
fprintf(stderr, "ERROR: munmap() failed.\n");
exit(EXIT_FAILURE);
}
}
// calculate starting address of new page
while (offset % mem_page_size)
offset--;
// try to map new memory page
mem_map_ptr = mmap(NULL, mem_page_size, PROT_READ | PROT_WRITE, MAP_SHARED,
mem_dev_fd, offset);
if (mem_map_ptr == MAP_FAILED) {
fprintf(stderr, "ERROR: mmap() failed.\n");
exit(EXIT_FAILURE);
}
// save last mapped page address
mem_base_addr = offset;
}
//------------------------------------------------------------------------------
// End-of-File
//------------------------------------------------------------------------------
