I swear checking registers made sense to me a few weeks ago when I was troubleshooting multichannel audio issues on the McASP but for the last two days I have been stumped how it ever made sense to me! Doh!
I understand that 48038000 is the McASP base address.
When I run: /devmem2 0x48038000
I expected to get: 0x44300A02h
But instead I get:
./devmem2 0x48038000
/dev/mem opened.
Memory mapped at address 0xb6f3a000.
Value at address 0x48038000 (0xb6f3a000): 0x44307B02
Have I been looking at the TRM for too long and need some sleep!!!
From the AM335x TRM it says on page 4597: http://www.ti.com/lit/ug/spruh73k/spruh73k.pdf
22.3.1.1 REV Register (offset = 0h) [reset = 44300A02h]
REV is shown in Figure 22-38 and described in Table 22-9.
The revision identification register (REV) contains identification data for the peripheral.
Figure 22-38. REV Register
LEGEND: R/W = Read/Write; R = Read only; W1toCl = Write 1 to clear bit; -n = value after reset Table 22-9. REV Register Field Descriptions
Version of devmem2.c: wget http://sources.buildroot.net/devmem2.c
Build: gcc devmem2.c -o devmem2