i.MX ProcessorsのトピックRe: uSDHC shared resources

uSDHC shared resources

RooperK — Fri, 23 Apr 2021 09:21:38 GMT

I have encountered a bit of understanding gap in which parts of a controller are common and which are dedicated to each channel.

Do reset registers on SYS_CTRL(RSTC, RSTD and RSTA) reset whole circuit or only channel, on which they are set(also, are RSTC and D necessary before RSTA)?
Are DLL and clock seperate or each time driver operates with another card it has to switch clock?

Re: uSDHC shared resources

igorpadykov — Fri, 23 Apr 2021 10:34:11 GMT

Hi Rooper

1. for uSDHC usage one can look at SDK example

https://github.com/RT-Thread/rt-thread/tree/master/bsp/imx6sx/iMX6_Platform_SDK/sdk/drivers/usdhc

2. all uSDHC instances are independent modules. So SYS_CTRL resets only one module.

Best regards
igor

Re: uSDHC shared resources

RooperK — Fri, 23 Apr 2021 12:45:19 GMT

Thank you for answer. As I understand, since each instance is seperate module, buffer, DLL and clock are seperate too? Documentation specifies broadcast commands, which are send to all cards. Are they confined to module or send to all modules?

Re: uSDHC shared resources

igorpadykov — Fri, 23 Apr 2021 13:49:26 GMT

yes they are separate.

Best regards
igor