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-rw-r--r--src/novena-eim.c708
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diff --git a/src/novena-eim.c b/src/novena-eim.c
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+/*
+ * 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 *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_OE_B, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_RW, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_LBA_B, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD00, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD01, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD02, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD03, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD04, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD05, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD06, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD07, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD08, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD09, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD10, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD11, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD12, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD13, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD14, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_AD15, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_WAIT_B, (uint32_t *)&reg_mux);
+ eim_write_32(IOMUXC_SW_MUX_CTL_PAD_EIM_BCLK, (uint32_t *)&reg_mux);
+
+ // we need to configure all the I/O pads too
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_CS0_B, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_OE_B, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_RW, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_LBA_B, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD00, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD01, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD02, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD03, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD04, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD05, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD06, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD07, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD08, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD09, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD10, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD11, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD12, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD13, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD14, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_AD15, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_WAIT_B, (uint32_t *)&reg_pad);
+ eim_write_32(IOMUXC_SW_PAD_CTL_PAD_EIM_BCLK, (uint32_t *)&reg_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
+//------------------------------------------------------------------------------