Re: RFC: ARM Boot standard for passing device tree blob
From: Russell King - ARM Linux <hidden>
Date: 2010-03-26 23:00:59
Also in:
linux-arm-kernel
Possibly related (same subject, not in this thread)
- 2010-03-31 · Re: RFC: ARM Boot standard for passing device tree blob · Ben Dooks <ben-linux@fluff.org>
- 2010-03-30 · RE: RFC: ARM Boot standard for passing device tree blob · Dave P. Martin <hidden>
- 2010-03-30 · Re: RFC: ARM Boot standard for passing device tree blob · Jamie Lokier <hidden>
- 2010-03-29 · RE: RFC: ARM Boot standard for passing device tree blob · "Dave P. Martin" <Dave.Martin@arm.com>
- 2010-03-26 · Re: RFC: ARM Boot standard for passing device tree blob · Russell King - ARM Linux <hidden>
On Fri, Mar 26, 2010 at 07:43:20AM -1000, Mitch Bradley wrote:
What is the reason for turning off the data caches? Leaving all caches turned on and coherent with one another has always worked well for me at the interface from firmware to a booted program.
With the data caches on, you need the MMU to be setup and operational. That's impractical when you're passing control between differing pieces of software which may have different ideas about how to setup the MMU and where to place the page tables. If you accidentally overwrite the page tables, things quickly become undebuggable.