Proposed changes to io.h

Christoph Hellwig hch at
Thu Apr 1 04:18:52 EST 2004

On Wed, Mar 31, 2004 at 10:44:25AM -0500, John Whitney wrote:
> 1. Modifications to virt_to_bus, bus_to_virt, virt_to_phys, and
> phys_to_virt.  With the use of fully virtual addresses for

These are all obsolete interface and you're not supposed to use them
for new plattforms or drivers at all.

> 2. I'd like to add 64-bit __raw_readll and __raw_writell routines to
> io.h, done using floating-point registers.  Currently, modules such as
> MTD (when writing to 64-bit buses) perform two 32-bit, non-atomic
> writes, which can cause problems.  Using a floating-point register to
> guarantee a 64-bit write is ugly, but it works.  Code for these inlined
> routines is as follows:

Standard-naming for those are readq/writeq afaik

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