[PATCH] ARM: 2691/1: PXA27x sleep fixes take 2

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>

1 files changed, 32 insertions, 0 deletions

diff --git a/arch/arm/mach-pxa/pxa27x.c b/arch/arm/mach-pxa/pxa27x.c
index 7e863afefb5..aa3c3b2ab75 100644
--- a/arch/arm/mach-pxa/pxa27x.c
+++ b/arch/arm/mach-pxa/pxa27x.c
@@ -120,6 +120,38 @@ EXPORT_SYMBOL(get_clk_frequency_khz);
 EXPORT_SYMBOL(get_memclk_frequency_10khz);
 EXPORT_SYMBOL(get_lcdclk_frequency_10khz);
 
+int pxa_cpu_pm_prepare(suspend_state_t state)
+{
+	switch (state) {
+	case PM_SUSPEND_MEM:
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+void pxa_cpu_pm_enter(suspend_state_t state)
+{
+	extern void pxa_cpu_standby(void);
+	extern void pxa_cpu_suspend(unsigned int);
+	extern void pxa_cpu_resume(void);
+
+	CKEN = CKEN22_MEMC | CKEN9_OSTIMER;
+
+	/* ensure voltage-change sequencer not initiated, which hangs */
+	PCFR &= ~PCFR_FVC;
+
+	/* Clear edge-detect status register. */
+	PEDR = 0xDF12FE1B;
+
+	switch (state) {
+	case PM_SUSPEND_MEM:
+		/* set resume return address */
+		PSPR = virt_to_phys(pxa_cpu_resume);
+		pxa_cpu_suspend(3);
+		break;
+	}
+}
 
 /*
  * device registration specific to PXA27x.