18 May
2012
18 May
'12
5:55 p.m.
On 05/18/2012 04:57 AM, Chang-Ming.Huang@freescale.com wrote:
From: Jerry Huang Chang-Ming.Huang@freescale.com
For FSL low-end processors (VVN2.2), in order to detect the SD card, we should enable PEREN, HCKEN and IPGEN to enable the clock. Otherwise, after booting the u-boot, and then inserting the SD card, the SD card can't be detected. For SDHC VVN2.3 IP, these bits are reserved, and SDCLKEN is used. And when accessing to these reserved bit, no any impact happened.
Again, have you talked to a hardware designer and confirmed that there's no impact from setting these bits on chips where they're reserved? Just because you don't notice any obvious impact doesn't mean it's totally safe.
-Scott