Zynq reads the internal temperature of the PHY chip.

Have you set the page address ?

Register 22 in any page sets the page to be accessed.

MK

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <linux/mii.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <linux/sockios.h>
#include <linux/types.h>
#include <netinet/in.h>
#include <unistd.h>
#include <time.h>

struct mii_ioctl_data
{
    __u16 phy_id;
    __u16 reg_num;
    __u16 val_in;
    __u16 val_out;
}

void help()
{
    printf("mdio:\n");
    printf("read operation: mdio phy_addr reg_addr\n");
    printf("write operation: mdio  phy_addr reg_addr value\n");
    printf("For example:\n");
    printf("mdio eth0 6 27\n");
    printf("mdio eth0 6 27 0x12\n\n");
}


int main(int nArgc, char *pArgv[])
{
    if (nArgc == 1 || !strcmp(pArgv[1], "-h"))
    {
        help();
        return 0;
    }

    struct mii_ioctl_data *pMiiData = NULL;
    struct ifreq oRegInfo;
    memset(&oRegInfo, 0, sizeof(oRegInfo));
    strncpy(oRegInfo.ifr_name, pArgv[1], IFNAMSIZ - 1);
    printf("ifreq name : %s\n", oRegInfo.ifr_name);

    int nRet = 0;
    int nSockFd = -1;

    do
    {
        nSockFd = socket(PF_LOCAL, SOCK_DGRAM, 0);
        if (nSockFd < 0)
        {
            break;
        }
        // get phy address in smi bus
        printf("Get phy address in smi bus...\n");
        nRet = ioctl(nSockFd, SIOCGMIIPHY, &oRegInfo);
        if (nRet < 0)
        {
            break;
        }

        pMiiData = (struct mii_ioctl_data*) &oRegInfo.ifr_data;
        if (4 == nArgc)
        {
            pMiiData->phy_id = (uint16_t) strtoul(pArgv[2], NULL, 0);;
            pMiiData->reg_num = (uint16_t) strtoul(pArgv[3], NULL, 0);
            printf("pht_id = %d, reg_num = %d\n", pMiiData->phy_id , pMiiData->reg_num);

            for (int nIdx = 0; nIdx != 1000; ++nIdx)
            {
                nRet = ioctl(nSockFd, SIOCGMIIREG, &oRegInfo);
                if (nRet < 0)
                {
                    printf("get register value failed\n");
                    break;
                }
                printf("read phy addr: 0x%x reg: 0x%x value : 0x%x\n\n",
                pMiiData->phy_id, pMiiData->reg_num, pMiiData->val_out);
                int nTempValue = ((pMiiData->val_out & 0xFF) - 25) * 1000;
                printf("Round %d temperature : %d\n", nIdx, nTempValue);

                struct timespec t;
                t.tv_sec = 1;
                t.tv_nsec = 0;
                nanosleep(&t, NULL);
            }
        }
        else if (5 == nArgc)
        {
            pMiiData->phy_id = (uint16_t) strtoul(pArgv[2], NULL, 0);;
            pMiiData->reg_num = (uint16_t) strtoul(pArgv[3], NULL, 0);
            pMiiData->val_in = (uint16_t) strtoul(pArgv[4], NULL, 0);
            printf("pht_id = %d, reg_num = %d, set_value = %d\n", pMiiData->phy_id , pMiiData->reg_num, pMiiData->val_in);
            nRet = ioctl(nSockFd, SIOCSMIIREG, &oRegInfo);
            if (nRet < 0)
            {
                printf("set register value failed\n");
                break;
            }
            printf("write phy addr: 0x%x reg: 0x%x value : 0x%x\n\n",
            pMiiData->phy_id, pMiiData->reg_num, pMiiData->val_in);

            for (int nIdx = 0; nIdx != 1000; ++nIdx)
            {
                nRet = ioctl(nSockFd, SIOCGMIIREG, &oRegInfo);
                if (nRet < 0)
                {
                    printf("get register value failed\n");
                    break;
                }
                printf("read phy addr: 0x%x reg: 0x%x value : 0x%x\n\n",
                pMiiData->phy_id, pMiiData->reg_num, pMiiData->val_out);

                int nTempValue = ((pMiiData->val_out & 0xFF) - 25) * 1000;
                printf("Round %d temperature : %d\n", nIdx, nTempValue);

                struct timespec t;
                t.tv_sec = 1;
                t.tv_nsec = 0;
                nanosleep(&t, NULL);
            }
        }
    } while (0);

    if (nSockFd >= 0)
    {
        close(nSockFd);
        nSockFd = -1;
    }
    return 0;
}

My code goes like this. Input argument examples are provided in sub-function HELP starting on line 23 above.

I've had a very quick look at your code  - I don't have time to pick through it all but:

The phy has an ID, that's in case there are more than one on the MDIO bus,

Inside the phy are several pages of registers, and the page you get access to depends on what is in register 22 which is common to all pages

Your code only seems to set phy_id and reg_num to access registers - you have to look after the page as well.

Find some registers on different pages in the data sheet and check the contents. Then adjust register 22 and do it again.

I think you'll find that you are operating with register 22 set to zero (power up default).

The Marvel data sheet does describe all this (I can't quite go so far as to suggest that it explains any of it very well )

MK

Hi MK:

Thanks for the tip, and that does the trick.