sh: Document PTEL 31:29 use on PTEA-wielding parts.

Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This commit is contained in:
Stuart Menefy 2007-11-30 18:05:18 +09:00 committed by Paul Mundt
parent 2adb4e1009
commit fc55888f83

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@ -22,8 +22,9 @@
* - Bits 10 and 11 are low bits of the PPN that are reserved on >= 4K pages.
* Bit 10 is used for _PAGE_ACCESSED, bit 11 remains unused.
*
* - Bits 31, 30, and 29 remain unused by everyone and can be used for future
* software flags, although care must be taken to update _PAGE_CLEAR_FLAGS.
* - On 29 bit platforms, bits 31 to 29 are used for the space attributes
* and timing control which (together with bit 0) are moved into the
* old-style PTEA on the parts that support it.
*
* XXX: Leave the _PAGE_FILE and _PAGE_WT overhaul for a rainy day.
*