Patch from Lothar Wassmann
The patch makes sure, that the ouptut functions of pins are restored
before restoring the Alternat Function settings, preventing pins from
being intermediately configured for undefined or unwanted alternate
functions.
Here is the original comment:
I've got a PXA270 system that uses GPIO80 as nCS4. This system did
hang on resume. Digging into the problem I found that the processor
stalled immediately when restoring the GAFR2_U register which restored
the alternate function for GPIO80. Since the GPDR registers were
restored after the GAFR registers, the offending GPIO was configured
as input at this point.
Thus the alternate function that was in effect after restoring the
GAFR was in fact the input function "MBREQ" instead of the output
function "nCS4". The "PXA27x Processor Family Developer's Manual"
(Footnote in Table 6-1 on page 6-3) states that:
"The MBREQ alternate function must not be enabled until the PSSR[RDH]
bit field is cleared. For more details, see Table 3-15, "PSSR Bit
Definitions" on page 3-71."
There is another note in the Developer's Manual (chapter 24.4.2
"GPIO operation as Alternate Function" on page 24-4)
stating that:
"Configuring a GPIO for an alternate function that is not defined for
it causes unpredictable results."
Since some GPIOs have no input function defined, and to prevent
inadvertedly programming the MBREQ function on some pin, the GAFR
registers should be restored after the GPDR registers have been
restored.
Additional provisions have to be made when the MBREQ function is
actually required. The corresponding GAFR bits should not be restored
with the regular GAFR restore, but must be set only after the PSSR
bits have been cleared.
Signed-off-by: Lothar Wassmann <LW@KARO-electronics.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Richard Purdie
Update the PXA pm.c file to allow machines (such as the Sharp
Zaurus) to override the standard pm functions but reuse/wrap them
where needed.
The init call is made slightly earlier to give machine code an init
level to override them in removing any race.
Signed-off-by: Richard Purdie
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We need to re-initialise the stack pointers for undefined, IRQ
and abort mode handlers whenever we resume.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Todd Poynor
PXA27x sleep fixes:
* set additional sleep/wakeup registers for Mainstone boards.
* move CKEN=0 to pxa25x-specific code; that value is harmful on pxa27x.
* save/restore additional registers, including some found necessary for
C5 processors and/or newer blob versions.
* enable future support of additional sleep modes for PXA27x (eg,
standby, deep sleep).
* split off cpu-specific sleep processing between pxa27x and pxa25x into
separate files (partly in preparation for additional sleep modes).
Includes fixes from David Burrage.
Signed-off-by: Todd Poynor
Signed-off-by: Nicolas Pitre
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Lothar Wassmann
Richard Purdie
Russell King
Todd Poynor
Linus Torvalds