Soft reset for C6748 Generic Secure boot.

Tuyen Nguyen

Dear TI experts,

I am trying to give a soft reset to a DSP 6748 using generic secure boot by manipulating RSCTRL register. But I have the same problem with Marcin Wyrwas in the following post

http://e2e.ti.com/support/dsp/tms320c6000_high_performance_dsps/f/115/t/158002.aspx

Could you give us some hint how to do a soft reset with secure boot? I flash the encrypted image in SPI memory and boot firmware from there.

this is the code I used for soft reset

    unsigned int val;
   val = REG(SOC_PLLC_0_REGS + PLLC_RSCTRL);
   /* unlock reg */

   LOG("Before unlock PLLC_RSCTRL = 0x%x\n", val);
   val = val & ~(0x0000FFFF);
   val = val | 0x5A69;

   REG(SOC_PLLC_0_REGS + PLLC_RSCTRL) = val;

   val = REG(SOC_PLLC_0_REGS + PLLC_RSCTRL);

   LOG("After unlock PLLC_RSCTRL = 0x%x\n", val);
   if((val & 0xFFFF) == 0xC)
   {
       // reset;
       LOG("Reset\n");
       val = 0x5A69; \\ val=0x0;
       REG(SOC_PLLC_0_REGS + PLLC_RSCTRL) = val;
   }

These are the printings:

Before unlock PLLC_RSCTRL = 0x10003
After unlock PLLC_RSCTRL = 0x1000c
Reset

Thank you very much for your help!

Best regards,

Tuyen Nguyen

over 13 years ago

0 Rahul Prabhu over 13 years ago

TI__Guru** 116770 points

Hi Tuyen,

Sorry for the delayed response here.

Issuing a soft reset to boot the device in secure mode is not a supported feature on the generic secure devices. The secure boot features of this device are enabled only on power on reset . When you exit in non-secure mode the device basically goes through a secure to non secure override sequence and exits in non-secure mode. Once this has occured, the only way to enter secure boot state is a power on reset.

The software reset does a limited reset on the device. In case of this reset the device doesn`t scan through its efuses and latch the boot pins. only content of internal memory is retained while the PLLs are reset.

Regards,

Rahul

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Soft reset for C6748 Generic Secure boot.