Errata regarding bus/physical address for BCM2835 #5
Description
In page 140 of your book, you mention that:
ARM bus address is 3f200000 - 3f2000b3 and ARM physical address is 0x7e200000
However reading page 6 of the BCM2835 ARM Peripheral document, it mentions that:
Physical addresses range from 0x3f000000 - 0x3fffffff and bus addresses start at 0x7e000000.
Finally it mentions that bus address 0x7fnnnnnn maps to 0x3fnnnnnn
The BCM2835 documentation is consistent with the output shown in page 139, and it makes sense as well that the left most column of /proc/iomem is the physical address and the one following @ is the bus address, because SYSTEM RAM will have a physical address but no bus address, while IO mapped devices will have both addresses.