i.MX Processors中的主题 Re: How to enable A7 LDO?

How to enable A7 LDO?

stanley_yeh — Thu, 08 Aug 2019 09:19:57 GMT

Hi,

I am using i.MX7ULP now and I want to enable A7 LDO.

I got some clues in 36.2.3.1 of IMX7ULPRMV2_RevC.pdf.

However, I don't know how to modify the parameter (please refer to the following image) of eFuse.

As I know, once the parameter be enabled, M4 will set PMC_0_CTRL[LDOEN] bit and the current of A7 domain will be from the internal LDO. Isn't it?

In addition, I can't find "fuse map" in the document as well.

Could you help me, please?

Re: How to enable A7 LDO?

igorpadykov — Fri, 09 Aug 2019 10:25:22 GMT

Hi Stanley

fuse map can be found in attachment section of Reference Manual,

also attached below.

i.MX 7ULP Applications Processor Reference Manual

Best regards
igor
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Re: How to enable A7 LDO?

stanley_yeh — Wed, 14 Aug 2019 09:58:12 GMT

Hi igorpadykov,

Thank you for your help.

In addition, if I want to set the "A7 LDO Enable" bit as 1, which value of u-boot command is correct?

A. fuse prog 2 3 0x00000001

B. fuse prog 2 3 0x01000000

Thanks a lot.

Re: How to enable A7 LDO?

igorpadykov — Wed, 14 Aug 2019 12:24:27 GMT

Hi Stanley

for fuses programming one can look on

Burning eFuses on i.MX6 and i.MX7 - i.MXDev Blog

Best regards
igor

Re: How to enable A7 LDO?

stanley_yeh — Thu, 15 Aug 2019 02:22:33 GMT

Hi igorpadykov,

I know how to program.

What I don't know is the address order, little-endian or big-endian?

In the Bank 2 Word 3, the byte order is "0x530 0x531 0x532 0x533" or "0x533 0x532 0x531 0x530"?

If I want to set the "A7 LDO Enable" bit as 1, which value of u-boot command is correct? 0x00000001 or 0x01000000?

Thanks.