The LogiCORE™ IP AXI IIC Bus Interface connects to the AMBA® AXI specification and provides a low-speed, two-wire,serial bus interface to a large number of popular devices. This product specification defines the architecture,hardware (signal) interface, software (register) interface, and parameterization options for the AXI IIC Bus Interface module.

HW IP Features

Compliant to industry standard I2C protocol
Register access through AXI4-Lite interface
Master or slave operation
Multi-master operation
Software selectable acknowledge bit
Arbitration lost interrupt with automatic mode switching from master to slave
Calling address identification interrupt with automatic mode switching from master to slave
START and STOP signal generation and detection
Repeated START signal generation •
Acknowledge bit generation and detection
Bus busy detection •
Fast-Mode Plus 1 MHz, Fast Mode 400 kHz, or Standard Mode 100 kHz operation
7-bit or 10-bit addressing • General call enable or disable
Transmit and receive FIFOs – 16 bytes deep
Throttling
General purpose output, 1-bit to 8 bits wide
Dynamic Start and Stop generation

Known Issues and limitations

No slave mode support as of now.
No bus recovery. This is because the controller does not give the status of the scl / sda pins and therefore getting the status may be difficult.
Receive data length maximum up to 255 bytes.

Kernel Configuration

I2C is not enabled in the current default kernel configuration. The following steps may be used to enable the driver in the kernel configuration

CONFIG_I2C_XILINX=y

Devicetree

https://github.com/Xilinx/linux-xlnx/blob/master/Documentation/devicetree/bindings/i2c/i2c-xiic.txt

IIC: i2c@81600000 {
    compatible = "xlnx,xps-iic-2.00.a";
    interrupt-parent = <&xps_intc_0>;
    interrupts = < 6 2 >;
    #address-cells = <1>;
    #size-cells = <0>;
 
    m24c08@50 {
        compatible = "at,24c08";
        reg = <0x50>;
    };
} ;

Test procedure

I2C EEPROM From A User Space Application

The following example reads and writes through the I2C EEPROM on the KC705 board. This example can be downloaded at the following link.

This assumes the /dev/i2c device file was created by the user or using udev.

NOTE: The EEPROM higher level driver referenced below cannot be built into the kernel for this example to work. An error that indicates the application cannot set the I2C address will occur if this is the case.

/*****************************************************************************/
/**
* @file i2c_test.c
* This file contains the linux example for i2c.
* Note:    10-bit addressing is not supported in the current linux driver.
* Repeated start also not supported in the current linux driver.
*
*
*
* @note     None.
*
*
******************************************************************************/
 
/***************************** Include Files *********************************/
 
#include <fcntl.h>
#include <stdio.h>
#include <linux/i2c-dev.h>
 
/************************** Constant Definitions *****************************/
 
#define I2C_SLAVE_FORCE 0x0706
#define I2C_SLAVE    0x0703    /* Change slave address            */
#define I2C_FUNCS    0x0705    /* Get the adapter functionality */
#define I2C_RDWR    0x0707    /* Combined R/W transfer (one stop only)*/
 
#define MUX_ADDR            0x74
#define EEPROM_ADDR            0x54
#define MUX_CHANNEL_KINTEX7        0x04
 
/*
 * Page size of the EEPROM. This depends on the type of the EEPROM available
 * on board.
 */
#define PAGESIZE                            16
 
/**************************** Type Definitions *******************************/
 
typedef unsigned char   Xuint8;
typedef char            Xint8;      /**< signed 8-bit */
typedef unsigned short  Xuint16;    /**< unsigned 16-bit */
typedef short           Xint16;     /**< signed 16-bit */
typedef unsigned long   Xuint32;    /**< unsigned 32-bit */
typedef long            Xint32;     /**< signed 32-bit */
typedef float           Xfloat32;   /**< 32-bit floating point */
typedef double          Xfloat64;   /**< 64-bit double precision floating point */
typedef unsigned long   Xboolean;   /**< boolean (XTRUE or XFALSE) */
typedef  Xuint8 AddressType;
 
/***************** Macros (Inline Functions) Definitions *********************/
 
/************************** Function Prototypes ******************************/
 
static int IicRead(void);
static int IicWrite(void);
static Xuint8 ReadEepromData(Xuint8 ReadBuffer[], Xuint8 NoOfBytes);
static Xuint8 WriteEepromData(Xuint8 ReadBuffer[], Xuint8 NoOfBytes);
static int IicMuxEnable(void);
 
/************************** Variable Definitions *****************************/
 
/*
 * FD of the IIC device opened.
 */
int Fdiic;
 
 
/**************************** Function Definitions ***************************/
 
/*****************************************************************************/
/**
*
* Entry point for integration tests on IIC.
*
* @param    .
*
* @return   0 if successful else -1.
*
* @note     None.
*
******************************************************************************/
int main()
{
    int Status;
    int TestLoops=1;
 
    /*
     * Open the device.
     */
    Fdiic = open("/dev/i2c", O_RDWR);
    if(Fdiic < 0)
    {
        printf("Cannot open the IIC device\n");
 
        return 1;
    }
 
    Status = IicMuxEnable();
     if (Status)
    {
        printf("Cannot Enable Mux device\n");
        close(Fdiic);
        return 1;
    }
 
    Status = IicWrite();
     if (Status)
    {
        printf("Cannot Wtite into EEPROM device\n");
        close(Fdiic);
        return 1;
    }
 
    Status = IicRead();
     if (Status)
    {
        printf("Cannot Read from EEPROM \n");
        close(Fdiic);
        return 1;
    }
 
    printf("eerprom test successfull \n");
    close(Fdiic);
 
    return 0;
}
 
 
 
/*****************************************************************************/
/**
*
* Read the data from the EEPROM.
*
* @param    TestLoops - indicates the number of time to execute the test.
*
* @return   Status of the read from EEPROM
*
* @note     None.
*
******************************************************************************/
static int IicRead()
{
    Xuint8 WriteBuffer [2];    /* Buffer to hold location address.*/
    Xuint8 ReadBuffer [PAGESIZE];    /* Buffer to hold data read.*/
    Xuint16 BytesToRead=PAGESIZE;
    Xuint8 BytesWritten;
    Xuint8 BytesRead=0;            /* Number of Bytes read from the IIC device. */
    Xuint16 Index;                /* Loop variable. */
    Xuint16 OffsetAddr = 0x0;    /* Address offset in EEPROM to be written. */
    Xuint8 ReadBytes;
    int Status = 0;
    Status = ioctl(Fdiic, I2C_SLAVE_FORCE, EEPROM_ADDR);
    if(Status < 0)
    {
        printf("\n Unable to set the EEPROM address\n");
 
        return -1;
    }
 
    OffsetAddr = EEPROM_ADDR;
    if(sizeof(AddressType) == 1)
    {
        WriteBuffer[0] = (Xuint8)(OffsetAddr);
    }
    else
    {
        WriteBuffer[0] = (Xuint8)(OffsetAddr >> 8);
        WriteBuffer[1] = (Xuint8)(OffsetAddr);
    }
 
    /*
     * Position the address pointer in EEPROM.
     */
    BytesWritten = write(Fdiic, WriteBuffer, sizeof(AddressType));
 
 
    /*
     * limit the bytes to be read to the Page size.
     */
    if(BytesToRead > PAGESIZE)
    {
        ReadBytes = PAGESIZE;
    }
    else
    {
        ReadBytes = BytesToRead;
    }
 
    /*
     * Read the bytes.
     */
    while(BytesToRead > 0)
    {
        printf ("Performing Read operation\n");
        BytesRead = ReadEepromData(ReadBuffer, ReadBytes);
        if(BytesRead != ReadBytes)
        {
            printf("\nITP_IIC_TEST1: Test Failed in read\n");
 
            return -1;
        }
 
        /*
         * Update the read counter.
         */
        BytesToRead -= BytesRead;
        if(BytesToRead > PAGESIZE)
        {
            ReadBytes = PAGESIZE;
        }
        else
        {
            ReadBytes = BytesToRead;
        }
 
    }
 
    printf("\nRead EEPROM Succesful\n");
 
    return 0;
}
 
/*****************************************************************************/
/**
*
* Write data to the EEPROM.
*
* @param    TestLoops - indicates the number of time to execute the test.
*
* @return   None.
*
* @note     None.
*
******************************************************************************/
static int IicWrite()
{
    Xuint8 WriteBuffer[PAGESIZE + sizeof(AddressType)]; /* Buffer to hold data to be written */
    Xuint16 BytesToWrite = PAGESIZE;
    Xuint8 BytesWritten;    /* Number of Bytes written to the IIC device. */
    Xuint16 Index;                /* Loop variable. */
    Xuint16 OffsetAddr = 0x0;    /* Address offset in EEPROM to be written. */
    Xuint16 OffsetAddrNew = 0x0;
    Xuint8 WriteBytes;
    Xuint8 Data = 0x0;
    char Input[8];
    int Status = 0;
    Status = ioctl(Fdiic, I2C_SLAVE_FORCE, EEPROM_ADDR);
    if(Status < 0)
    {
        printf("\n Unable to set the EEPROM address\n");
 
        return -1;
    }
 
    Data = 0x11;
    OffsetAddr = EEPROM_ADDR;
    /*
     * Load the offset address inside EEPROM where data need to be written.
     */
        if(sizeof(AddressType) == 1)
    {
        WriteBuffer[0] = (Xuint8)(OffsetAddr);
     }
    else
    {
        WriteBuffer[0] = (Xuint8)(OffsetAddr >> 8);
        WriteBuffer[1] = (Xuint8)(OffsetAddr);
    }
 
    /*
     * Load the data to be written into the buffer.
     */
    for(Index = 0; Index < PAGESIZE; Index++)
    {
        WriteBuffer[Index + sizeof(AddressType)] = Data;
    }
 
    /*
     * Limit the number of bytes to the page size.
     */
    if(BytesToWrite > PAGESIZE)
    {
        WriteBytes = PAGESIZE + sizeof(AddressType);
    }
    else
    {
        WriteBytes = BytesToWrite + sizeof(AddressType);
    }
 
    while(BytesToWrite > 0)
    {
        /*
         * Write the data.
         */
        BytesWritten = WriteEepromData(WriteBuffer, WriteBytes);
        if(BytesWritten != WriteBytes)
        {
            printf("\nTest Failed in write\n");
            return -1;
        }
 
        /*
         * Update the write counter.
         */
        BytesToWrite -= (BytesWritten - sizeof(AddressType));
        if(BytesToWrite > PAGESIZE)
        {
            WriteBytes = PAGESIZE + sizeof(AddressType);
        }
        else
        {
            WriteBytes = BytesToWrite + sizeof(AddressType);
        }
 
        /*
         * Increment the offset address.
         */
        OffsetAddr += PAGESIZE;
 
        /*
         * Increment the data.
         */
        Data++;
 
        /*
         * load the new offset address.
         */
        if(sizeof(AddressType) == 1)
        {
            WriteBuffer[0] = (Xuint8)(OffsetAddr);
        }
        else
        {
            WriteBuffer[0] = (Xuint8)(OffsetAddr >> 8);
            WriteBuffer[1] = (Xuint8)(OffsetAddr);
         }
 
        /*
         * load the new data into buffer.
         */
        for(Index = 0; Index < PAGESIZE; Index++)
        {
            WriteBuffer[Index + sizeof(AddressType)] = Data;
        }
    }
 
    printf("\nWrite EEPROM Succesful\n");
 
    return 0;
}
 
/*****************************************************************************/
/**
*
* Write the data to the Slave device.
*
* @param    WriteBuffer - Buffer to hold the data to be transmitted on the Bus.
* @param    NoOfBytes    - Number of bytes to be written onto the bus.
*
* @return   Number of bytes written onto the bus.
*
* @note     None.
*
******************************************************************************/
static Xuint8 WriteEepromData(Xuint8 WriteBuffer[], Xuint8 NoOfBytes)
{
    Xuint8 BytesWritten;    /* Number of Bytes written to the IIC device. */
 
    /*
     * Write the bytes onto the bus.
     */
    BytesWritten = write(Fdiic, WriteBuffer, NoOfBytes);
 
    /*
     * Wait till the EEPROM internally completes the write cycle.
     */
    sleep(1);
 
    return BytesWritten;
}
 
/*****************************************************************************/
/**
*
* Read the data from the Slave device.
*
* @param    ReadBuffer  - Buffer to hold the data received on the bus.
* @param    NoOfBytes    - Number of bytes to be read from the bus.
*
* @return   Number of bytes read from the bus.
*
* @note     None.
*
******************************************************************************/
static Xuint8 ReadEepromData(Xuint8 ReadBuffer[], Xuint8 NoOfBytes)
{
    Xuint8 BytesRead;    /* Number of Bytes read from the device. */
 
    /*
     * Read the bytes from the bus.
     */
    BytesRead = read(Fdiic, ReadBuffer, NoOfBytes);
 
    return BytesRead;
}
 
 
 
/*****************************************************************************/
/**
*
* Enable the MUX Switch that routes to EEPROM. Mux Reg = 0x04 for Kintex-7
*
* @return   None.
*
* @note     None.
*
******************************************************************************/
 
 
static int IicMuxEnable(void)
{
    Xuint8 WriteBuffer[2];    /* Buffer to hold location address.*/
    Xuint8 ReadBuffer = 0x0;    /* Buffer to hold data read.*/
    Xuint16 BytesToRead;
    Xuint8 BytesWritten;
    Xuint8 BytesRead;            /* Number of Bytes read from the IIC device. */
    Xuint16 Index;                /* Loop variable. */
    Xuint16 Sel_Channel = 0x0;
    Xuint32 Mux_Reg = 0x1;
    Xuint8 ReadBytes;
    int Status;
    char Input[8];
 
    Status = ioctl(Fdiic, I2C_SLAVE_FORCE, MUX_ADDR);
    if(Status < 0)
    {
        printf("\n Unable to set the Mux address\n");
 
        return -1;
    }
 
    Sel_Channel = MUX_CHANNEL_KINTEX7;
 
    Mux_Reg = Mux_Reg << (Sel_Channel - 1);
    WriteBuffer[0] = Mux_Reg;
 
    printf("Selected Channel [%d] Mux Reg Value[%x]\n", Sel_Channel, Mux_Reg);
 
    /*
     * Position the address pointer in EEPROM.
     */
    BytesWritten = write(Fdiic, WriteBuffer, 1);
    if(BytesWritten != 1)
    {
        printf("Write Mux Reg failed\n");
        return -1;
    }
 
    BytesToRead = read(Fdiic, &ReadBuffer, 1);
    if(BytesToRead != 1)
    {
        printf("Read Mux Reg failed\n");
        return -1;
    }
    printf("Mux Reg Expected[%x] Actual[%x]\n", Mux_Reg, ReadBuffer);
 
    printf("\nMux Enable for EEPROM Succesful\n");
 
    return 0;
}

Using An I2C EEPROM Driver As A Higher Layer

I2C EEPROM Driver Kernel Configuration

There are higher layer drivers that allow the I2C driver to be used to access other devices such as the I2C serial EEPROM on the ML507 board. The following steps may be used to enable the driver in the kernel configuration.

From the device drivers menu, select Misc devices
Select EEPROM Support
Select I2C EEPROMs from most vendors

Adding An I2C EEPROM To The Device Tree

The following example shows adding the I2C EEPROM for the ML507 to it's device tree. The value of 0x050 is the I2C address of the EEPROM.

The device-tree generator for the EDK does not create this device on the I2C bus.

IIC: i2c@81600000 {
    compatible = "xlnx,xps-iic-2.00.a";
    interrupt-parent = <&xps_intc_0>;
    interrupts = < 6 2 >;
    reg = < 0x81600000 0x10000 >;
    #address-cells = <1>;
    #size-cells = <0>;
 
    m24c08@50 {
        compatible = "at,24c08";
        reg = <0x50>;
    };
} ;

Expected Output

The following kernel output (or similar) shows the EEPROM driver was started.

Device Tree Probing 'i2c'
81600000.i2c #0 at 0x81600000 mapped to 0xD1020000, irq=20
at24 0-0050: 1024 byte 24c08 EEPROM (writable)

U-Boot 2016.07 (Nov 30 2016 - 10:58:35 +0530)
 
 
 
DRAM:  ECC disabled 1 GiB
 
MMC:   sdhci@e0100000: 0
 
SF: Detected N25Q128A with page size 256 Bytes, erase size 64 KiB, total 16 MiB
 
*** Warning - bad CRC, using default environment
 
 
 
In:    serial
 
Out:   serial
 
Err:   serial
 
Net:   ZYNQ GEM: e000b000, phyaddr 7, interface rgmii-id
 
eth0: ethernet@e000b000
 
U-BOOT for
 
 
 
ethernet@e000b000 Waiting for PHY auto negotiation to complete...... done
 
BOOTP broadcast 1
 
BOOTP broadcast 2
 
BOOTP broadcast 3
 
DHCP client bound to address 10.10.70.5 (1003 ms)
 
Hit any key to stop autoboot:  4  0
 
U-Boot-PetaLinux> bootm 0x3000000
 
## Loading kernel from FIT Image at 03000000 ...
 
   Using 'conf@1' configuration
 
   Verifying Hash Integrity ... OK
 
   Trying 'kernel@1' kernel subimage
 
     Description:  PetaLinux Kernel
 
     Type:         Kernel Image
 
     Compression:  gzip compressed
 
     Data Start:   0x030000f0
 
     Data Size:    7967175 Bytes = 7.6 MiB
 
     Architecture: ARM
 
     OS:           Linux
 
     Load Address: 0x00008000
 
     Entry Point:  0x00008000
 
     Hash algo:    crc32
 
     Hash value:   12d074ef
 
   Verifying Hash Integrity ... crc32+ OK
 
## Loading fdt from FIT Image at 03000000 ...
 
   Using 'conf@1' configuration
 
   Trying 'fdt@1' fdt subimage
 
     Description:  Flattened Device Tree blob
 
     Type:         Flat Device Tree
 
     Compression:  uncompressed
 
     Data Start:   0x0379939c
 
     Data Size:    15832 Bytes = 15.5 KiB
 
     Architecture: ARM
 
     Hash algo:    crc32
 
     Hash value:   d105e61e
 
   Verifying Hash Integrity ... crc32+ OK
 
   Booting using the fdt blob at 0x379939c
 
   Uncompressing Kernel Image ... OK
 
   Loading Device Tree to 07ff9000, end 07fffdd7 ... OK
 
 
 
Starting kernel ...
 
 
 
Booting Linux on physical CPU 0x0
 
 
Linux version 4.6.0-xilinx (sivaraj@xhdrfl23) (gcc version 5.2.1 20151005 (Linaro GCC 5.2-2015.11-2) ) #2 SMP PREEMPT Wed Nov 30 11:01:30 IST 2016
 
 
CPU: ARMv7 Processor [413fc090] revision 0 (ARMv7), cr=18c5387d
 
 
CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache
 
 
Machine model: Xilinx-ZC702-2016.3
 
 
bootconsole [earlycon0] enabled
 
 
cma: Reserved 16 MiB at 0x3f000000
 
 
Memory policy: Data cache writealloc
 
 
percpu: Embedded 12 pages/cpu @ef7d1000 s19968 r8192 d20992 u49152
 
 
Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 260608
 
 
Kernel command line: console=ttyPS0,115200 earlyprintk
 
 
PID hash table entries: 4096 (order: 2, 16384 bytes)
 
 
Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
 
 
Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
 
 
Memory: 1010264K/1048576K available (5280K kernel code, 221K rwdata, 1812K rodata, 5120K init, 211K bss, 21928K reserved, 16384K cma-reserved, 245760K highmem)
 
 
Virtual kernel memory layout:
 
 
    vector  : 0xffff0000 - 0xffff1000   (   4 kB)
 
 
    fixmap  : 0xffc00000 - 0xfff00000   (3072 kB)
 
 
    vmalloc : 0xf0800000 - 0xff800000   ( 240 MB)
 
 
    lowmem  : 0xc0000000 - 0xf0000000   ( 768 MB)
 
 
    pkmap   : 0xbfe00000 - 0xc0000000   (   2 MB)
 
 
    modules : 0xbf000000 - 0xbfe00000   (  14 MB)
 
 
      .text : 0xc0008000 - 0xc07ed3f4   (8085 kB)
 
 
      .init : 0xc0800000 - 0xc0d00000   (5120 kB)
 
 
      .data : 0xc0d00000 - 0xc0d37760   ( 222 kB)
 
 
       .bss : 0xc0d37760 - 0xc0d6c700   ( 212 kB)
 
 
Preemptible hierarchical RCU implementation.
 
 
    Build-time adjustment of leaf fanout to 32.
 
 
    RCU restricting CPUs from NR_CPUS=4 to nr_cpu_ids=2.
 
 
RCU: Adjusting geometry for rcu_fanout_leaf=32, nr_cpu_ids=2
 
 
NR_IRQS:16 nr_irqs:16 16
 
 
efuse mapped to f0802000
 
 
slcr mapped to f0804000
 
 
L2C: platform modifies aux control register: 0x72360000 -> 0x72760000
 
 
L2C: DT/platform modifies aux control register: 0x72360000 -> 0x72760000
 
 
L2C-310 erratum 769419 enabled
 
 
L2C-310 enabling early BRESP for Cortex-A9
 
 
L2C-310 full line of zeros enabled for Cortex-A9
 
 
L2C-310 ID prefetch enabled, offset 1 lines
 
 
L2C-310 dynamic clock gating enabled, standby mode enabled
 
 
L2C-310 cache controller enabled, 8 ways, 512 kB
 
 
L2C-310: CACHE_ID 0x410000c8, AUX_CTRL 0x76760001
 
 
zynq_clock_init: clkc starts at f0804100
 
 
Zynq clock init
 
 
sched_clock: 64 bits at 333MHz, resolution 3ns, wraps every 4398046511103ns
 
 
clocksource: arm_global_timer: mask: 0xffffffffffffffff max_cycles: 0x4ce07af025, max_idle_ns: 440795209040 ns
 
 
Switching to timer-based delay loop, resolution 3ns
 
 
clocksource: ttc_clocksource: mask: 0xffff max_cycles: 0xffff, max_idle_ns: 537538477 ns
 
 
timer #0 at f080c000, irq=17
 
 
Console: colour dummy device 80x30
 
 
Calibrating delay loop (skipped), value calculated using timer frequency.. 666.66 BogoMIPS (lpj=3333333)
 
 
pid_max: default: 32768 minimum: 301
 
 
Mount-cache hash table entries: 2048 (order: 1, 8192 bytes)
 
 
Mountpoint-cache hash table entries: 2048 (order: 1, 8192 bytes)
 
 
CPU: Testing write buffer coherency: ok
 
 
CPU0: thread -1, cpu 0, socket 0, mpidr 80000000
 
 
Setting up static identity map for 0x100000 - 0x100058
 
 
CPU1: thread -1, cpu 1, socket 0, mpidr 80000001
 
 
Brought up 2 CPUs
 
 
SMP: Total of 2 processors activated (1333.33 BogoMIPS).
 
 
CPU: All CPU(s) started in SVC mode.
 
 
devtmpfs: initialized
 
 
VFP support v0.3: implementor 41 architecture 3 part 30 variant 9 rev 4
 
 
clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns
 
 
pinctrl core: initialized pinctrl subsystem
 
 
NET: Registered protocol family 16
 
 
DMA: preallocated 256 KiB pool for atomic coherent allocations
 
 
cpuidle: using governor ladder
 
 
cpuidle: using governor menu
 
 
hw-breakpoint: found 5 (+1 reserved) breakpoint and 1 watchpoint registers.
 
 
hw-breakpoint: maximum watchpoint size is 4 bytes.
 
 
zynq-ocm f800c000.ocmc: ZYNQ OCM pool: 256 KiB @ 0xf0880000
 
 
zynq-pinctrl 700.pinctrl: zynq pinctrl initialized
 
 
GPIO IRQ not connected
 
 
XGpio: /amba_pl/gpio@41200000: registered, base is 902
 
 
vgaarb: loaded
 
 
SCSI subsystem initialized
 
 
usbcore: registered new interface driver usbfs
 
 
usbcore: registered new interface driver hub
 
 
usbcore: registered new device driver usb
 
 
media: Linux media interface: v0.10
 
 
Linux video capture interface: v2.00
 
 
pps_core: LinuxPPS API ver. 1 registered
 
 
pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti <giometti@linux.it>
 
 
PTP clock support registered
 
 
EDAC MC: Ver: 3.0.0
 
 
Advanced Linux Sound Architecture Driver Initialized.
 
 
clocksource: Switched to clocksource arm_global_timer
 
 
NET: Registered protocol family 2
 
 
TCP established hash table entries: 8192 (order: 3, 32768 bytes)
 
 
TCP bind hash table entries: 8192 (order: 4, 65536 bytes)
 
 
TCP: Hash tables configured (established 8192 bind 8192)
 
 
UDP hash table entries: 512 (order: 2, 16384 bytes)
 
 
UDP-Lite hash table entries: 512 (order: 2, 16384 bytes)
 
 
NET: Registered protocol family 1
 
 
RPC: Registered named UNIX socket transport module.
 
 
RPC: Registered udp transport module.
 
 
RPC: Registered tcp transport module.
 
 
RPC: Registered tcp NFSv4.1 backchannel transport module.
 
 
hw perfevents: enabled with armv7_cortex_a9 PMU driver, 7 counters available
 
 
futex hash table entries: 512 (order: 3, 32768 bytes)
 
 
workingset: timestamp_bits=28 max_order=18 bucket_order=0
 
 
jffs2: version 2.2. (NAND) (SUMMARY)  Â© 2001-2006 Red Hat, Inc.
 
 
bounce: pool size: 64 pages
 
 
io scheduler noop registered
 
 
io scheduler deadline registered
 
 
io scheduler cfq registered (default)
 
 
dma-pl330 f8003000.dmac: Loaded driver for PL330 DMAC-241330
 
 
dma-pl330 f8003000.dmac:     DBUFF-128x8bytes Num_Chans-8 Num_Peri-4 Num_Events-16
 
 
e0001000.serial: ttyPS0 at MMIO 0xe0001000 (irq = 144, base_baud = 3125000) is a xuartps
 
àconsole [ttyPS0] enabled
 
console [ttyPS0] enabled
 
 
bootconsole [earlycon0] disabled
 
bootconsole [earlycon0] disabled
 
 
xdevcfg f8007000.devcfg: ioremap 0xf8007000 to f0904000
 
[drm] Initialized drm 1.1.0 20060810
 
brd: module loaded
 
loop: module loaded
 
m25p80 spi0.0: found n25q128a11, expected n25q128a13
 
m25p80 spi0.0: n25q128a11 (16384 Kbytes)
 
4 ofpart partitions found on MTD device spi0.0
 
Creating 4 MTD partitions on "spi0.0":
 
0x000000000000-0x000000500000 : "boot"
 
0x000000500000-0x000000520000 : "bootenv"
 
0x000000520000-0x000000fa0000 : "kernel"
 
0x000000fa0000-0x000001000000 : "spare"
 
CAN device driver interface
 
gpiod_set_value: invalid GPIO
 
libphy: MACB_mii_bus: probed
 
mdio_bus e000b000.etherne:07: mdio_device_register
 
macb e000b000.ethernet eth0: no PHY found
 
e1000e: Intel(R) PRO/1000 Network Driver - 3.2.6-k
 
e1000e: Copyright(c) 1999 - 2015 Intel Corporation.
 
ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
 
ehci-pci: EHCI PCI platform driver
 
usbcore: registered new interface driver usb-storage
 
e0002000.usb supply vbus not found, using dummy regulator
 
ULPI transceiver vendor/product ID 0x0424/0x0007
 
Found SMSC USB3320 ULPI transceiver.
 
ULPI integrity check: passed.
 
ci_hdrc ci_hdrc.0: EHCI Host Controller
 
ci_hdrc ci_hdrc.0: new USB bus registered, assigned bus number 1
 
ci_hdrc ci_hdrc.0: USB 2.0 started, EHCI 1.00
 
hub 1-0:1.0: USB hub found
 
hub 1-0:1.0: 1 port detected
 
mousedev: PS/2 mouse device common for all mice
 
i2c /dev entries driver
 
i2c i2c-0: Added multiplexed i2c bus 1
 
i2c i2c-0: Added multiplexed i2c bus 2
 
at24 3-0054: 1024 byte 24c08 EEPROM, writable, 1 bytes/write
 
i2c i2c-0: Added multiplexed i2c bus 3
 
i2c i2c-0: Added multiplexed i2c bus 4
 
rtc-pcf8563 5-0051: chip found, driver version 0.4.4
 
rtc-pcf8563 5-0051: rtc core: registered rtc-pcf8563 as rtc0
 
i2c i2c-0: Added multiplexed i2c bus 5
 
i2c i2c-0: Added multiplexed i2c bus 6
 
i2c i2c-0: Added multiplexed i2c bus 7
 
i2c i2c-0: Added multiplexed i2c bus 8
 
pca954x 0-0074: registered 8 multiplexed busses for I2C switch pca9548
 
Xilinx Zynq CpuIdle Driver started
 
sdhci: Secure Digital Host Controller Interface driver
 
sdhci: Copyright(c) Pierre Ossman
 
sdhci-pltfm: SDHCI platform and OF driver helper
 
mmc0: SDHCI controller on e0100000.sdhci [e0100000.sdhci] using DMA
 
ledtrig-cpu: registered to indicate activity on CPUs
 
usbcore: registered new interface driver usbhid
 
usbhid: USB HID core driver
 
si570 1-005d: registered, current frequency 148500000 Hz
 
NET: Registered protocol family 17
 
can: controller area network core (rev 20120528 abi 9)
 
NET: Registered protocol family 29
 
can: raw protocol (rev 20120528)
 
can: broadcast manager protocol (rev 20120528 t)
 
can: netlink gateway (rev 20130117) max_hops=1
 
Registering SWP/SWPB emulation handler
 
rtc-pcf8563 5-0051: setting system clock to 2016-11-30 05:34:07 UTC (1480484047)
 
ALSA device list:
 
  No soundcards found.
 
Freeing unused kernel memory: 5120K (c0800000 - c0d00000)
 
 
INIT: version 2.88 booting
 
 
usb 1-1: new high-speed USB device number 2 using ci_hdrc
 
mmc0: new high speed SDHC card at address 1234
 
mmcblk0: mmc0:1234 SA04G 3.64 GiB
 
 mmcblk0: p1
 
usb-storage 1-1:1.0: USB Mass Storage device detected
 
scsi host0: usb-storage 1-1:1.0
 
FAT-fs (mmcblk0p1): Invalid FSINFO signature: 0x00000689, 0x00000702 (sector = 1)
 
FAT-fs (mmcblk0p1): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
 
bootlogd: cannot allocate pseudo tty: No such file or directory
 
Creating /dev/flash/* device nodes
 
random: dd urandom read with 4 bits of entropy available
 
Starting internet superserver: inetd.
 
 
INIT: Entering runlevel: 5
 
 
Configuring network interfaces... ifconfig: SIOCGIFFLAGS: No such device
 
scsi 0:0:0:0: Direct-Access     SanDisk  Cruzer           1.26 PQ: 0 ANSI: 6
 
sd 0:0:0:0: Attached scsi generic sg0 type 0
 
sd 0:0:0:0: [sda] 15633408 512-byte logical blocks: (8.00 GB/7.45 GiB)
 
 
 
 
PetaLinux 2016.3 Xilinx-ZC702-2016_3 /dev/ttyPS0
 
 
Xilinx-ZC702-2016_3 login: sd 0:0:0:0: [sda] Write Protect is off
 
sd 0:0:0:0: [sda] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
 
 sda: sda1
 
sd 0:0:0:0: [sda] Attached SCSI disk
 
root
 
Password:
 
login[966]: root login on 'ttyPS0'
 
 
 
 
7[r[999;999H[6n8root@Xilinx-ZC702-2016_3:~# pwd
 
/home/root
 
root@Xilinx-ZC702-2016_3:~# i2cdetect -l | grep  xiic-i2c
 
i2c-0    i2c           xiic-i2c                            I2C adapter
 
root@Xilinx-ZC702-2016_3:~# i2cdetect -y 0x3
 
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
 
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
 
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
50: -- -- -- -- UU UU UU UU -- -- -- -- -- -- -- --
 
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
70: -- -- -- -- UU -- -- --
 
root@Xilinx-ZC702-2016_3:~#  i2cdump -y  -f 0x3 0x54
 
No size specified (using byte-data access)
 
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f    0123456789abcdef
 
00: 01 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
10: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
20: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
30: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
40: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
50: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
60: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
70: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
80: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
90: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
a0: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
b0: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
c0: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
d0: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
e0: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
f0: 0a 0b 0c 0d 0e 0f 10 11 12 13 14 15 16 17 18 19    ????????????????
 
root@Xilinx-ZC702-2016_3:~# i2cget -y -f 0x3 0x54 0
 
0x01
 
root@Xilinx-ZC702-2016_3:~# i2cset -y -f  0x3 0x54 0 1
 
root@Xilinx-ZC702-2016_3:~# i2cget -y -f 0x3 0x54 0 | grep 0x01
 
0x01
 
root@Xilinx-ZC702-2016_3:~# i2cget -y -f 0x3 0x54 0 | grep 0x01 | if [ $? -ne 0
 
 
]; then echo Unsuccessful ;else echo Passed;  fi
 
Passed
 
root@Xilinx-ZC702-2016_3:~#
 
root@Xilinx-ZC702-2016_3:~#

root@Xilinx-KC705-2013:~#

SysFS Interface.
The EEPROM driver allows the contents of the EEPROM to be seen in the sys file system at /sys/bus/i2c/devices/0-0050/eeprom.
The file,eeporm, is a file that can be read and written from user space.
If the sys file system is not mounted (no /sys dir), then the following commands will create and mount it.

bash > mkdir /sys/
bash > mount -t sysfs sysfs sys

The following shell commands can view the contents of the eeprom by 1st capturing it and then displaying the file as binary data.

bash> more /sys/bus/i2c/devices/0-0050/eeprom > eeprom.txt | od -x

The following command will write "01234567890DEADBEEFCAFE" to the EEPROM. Be careful as the ethernet MAC address is in the EEPROM and can be overwritten.

echo 0123456789DEADBEEFCAFE > /sys/bus/i2c/devices/0-0050/eeprom

code
Using An Aardvark I2C/SPI Activity Board For I2C EEPROM Testing

TotalPhase, the company that sells the Aardvark I2C test equipment, also sells a small board that we can use for our own testing, independent of the Aardvark. The board has an I2C EEPROM and an SPI EEPROM on it such that it can be connected to an FPGA board pretty easy.

http://www.totalphase.com/products/activity_board/
http://www.totalphase.com/download/pdf/activity-board-v1.00.pdf
http://www.totalphase.com/products/split_cable/

The point of this exercise is to have a standard test for the I2C that can be used across all boards.

See the following page, I2C With The Aardvark Board, for more information on how to do it.

Mainline Status

This driver is currently in sync with mainline kernel driver.

Change Log

2025.1

Summary:

improve error message when transfer fails to start
Wait for TX empty to avoid missed TX NAKs
Try re-initialization on bus busy timeout
Fix pm_runtime_set_suspended() with runtime pm enabled
Relocate xiic_i2c_runtime_suspend and xiic_i2c_runtime_resume to facilitate atomic mode
Add atomic transfer support

Commits:

ee1691d - i2c: xiic: improve error message when transfer fails to start

521da1e - i2c: xiic: Wait for TX empty to avoid missed TX NAKs

1d4a1ad - i2c: xiic: Try re-initialization on bus busy timeout

0c8d604 - i2c: xiic: Fix pm_runtime_set_suspended() with runtime pm enabled

84e2695 - i2c: xiic: Relocate xiic_i2c_runtime_suspend and xiic_i2c_runtime_resume to facilitate atomic mode

78efe95 - i2c: xiic: Add atomic transfer support

2024.2

None.

2024.1

Summary:

Remove some dead code
hide OF related data for COMPILE_TEST
Use devm_platform_get_and_ioremap_resource()
Fix runtime PM leak on error path
Convert to platform remove callback returning void
Use devm_clk_get_enabled()
Don't try to handle more interrupt events after error
Correct return value check for xiic_reinit()

Commits:

8c266d0 - i2c: xiic: Remove some dead code

58c043d - i2c: xiic: hide OF related data for COMPILE_TEST

0cc9841 - i2c: xiic: Use devm_platform_get_and_ioremap_resource()

d663d93 - i2c: xiic: xiic_xfer(): Fix runtime PM leak on error path

e190a0c - i2c: Convert to platform remove callback returning void

8390dc7 - i2c: xiic: Use devm_clk_get_enabled()

cb6e45c - i2c: xiic: Don't try to handle more interrupt events after error

59851fb - i2c: xiic: Correct return value check for xiic_reinit()

2023.2

None

2023.1

Summary:

Return value of xiic_reinit
Fix coding style issues
Fix Tx Interrupt path for grouped messages
Correct the datatype for rx_watermark
Fix the type check for xiic_wakeup
Add platform module alias
Add standard mode support for > 255 byte
Fix Rx and Tx paths in standard mode
Switch to Xiic standard mode for i2c-read
Add wait for FIFO empty in send_tx
Add smbus_block_read functionality
Remove interrupt enable/disable in Rx path
Update compatible with new IP version
Add SCL frequency configuration support
Make sure to disable clock on .remove()

Commits:

9de79b0 - i2c: xiic: return value of xiic_reinit

b3672b1 - i2c: xiic: Fix coding style issues

e323b54 - i2c: xiic: Fix Tx Interrupt path for grouped messages

3c9fedf - i2c: xiic: Correct the datatype for rx_watermark

e749e4f - i2c: xiic: Fix the type check for xiic_wakeup

b8caf0a - i2c: xiic: Add platform module alias

467d591 - i2c: xiic: Add standard mode support for > 255 byte

a411926 - i2c: xiic: Fix Rx and Tx paths in standard mode

6a0bb6c - i2c: xiic: Switch to Xiic standard mode for i2c-read

8dfacfb - i2c: xiic: Add wait for FIFO empty in send_tx

dfa73e8 - i2c: xiic: Add smbus_block_read functionality

c03d6cc - i2c: xiic: Remove interrupt enable/disable in Rx path

05e6c4a - i2c: xiic: Update compatible with new IP version

5375a17 - i2c: xiic: Add SCL frequency configuration support

c939c23 - i2c: xiic: Make sure to disable clock on .remove()

2022.2

Summary:

Make bus names unique

Commits:

1ef47d9 - i2c: xiic: Make bus names unique

2022.1

Summary:

Correct the BNB interrupt enable sequence

Commits:

7599019 - i2c: xiic: Correct the BNB interrupt enable sequence

Related Links

Xilinx Wiki

Linux I2C Driver

Table of Contents

HW IP Features

Known Issues and limitations

Kernel Configuration

Devicetree

Test procedure

Expected Output

Mainline Status

Change Log

2025.1

2024.2

2024.1

2023.2

2023.1

2022.2

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