ARM: imx: clean and consolidate imx5 suspend and idle code

The imx5 idle code that existed in mm-imx5.c is moved to pm-imx5.c.
The imx5_pm_init call is now exported and called during the
MACHINE_START late_init in supported imx5 platforms.

Remove various enabling/disabling of the gpc_dvfs clock and
enable it once during initialization.  This is a very low
power clock that must be enabled during low power operations.

There are only two "suspend_state_t" imx5 low power modes ever
used.  STOP_POWER_OFF for suspend to mem and
WAIT_UNCLOCKED_POWER_OFF for idle and suspend to standby.  The
latter mode only requires 500 nanoseconds of extra hardware
exit time beyond a basic WFI operation (WAIT_CLOCKED mode) so
no other idle mode is necessary.  Given this information, it
is more efficient to keep the registers in the often used
WAIT_UNCLOCKED_POWER_OFF state and only to and from the
STOP_POWER_OFF register state as needed when suspend to
mem is required.

Signed-off-by: Robert Lee <rob.lee@linaro.org>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 1 insertions, 20 deletions

diff --git a/arch/arm/mach-imx/mm-imx5.c b/arch/arm/mach-imx/mm-imx5.c
index feeee17da96..d84421e1467 100644
--- a/arch/arm/mach-imx/mm-imx5.c
+++ b/arch/arm/mach-imx/mm-imx5.c
@@ -16,7 +16,6 @@
 #include <linux/clk.h>
 #include <linux/pinctrl/machine.h>
 
-#include <asm/system_misc.h>
 #include <asm/mach/map.h>
 
 #include <mach/hardware.h>
@@ -24,24 +23,6 @@
 #include <mach/devices-common.h>
 #include <mach/iomux-v3.h>
 
-static struct clk *gpc_dvfs_clk;
-
-static void imx5_idle(void)
-{
-	/* gpc clock is needed for SRPG */
-	if (gpc_dvfs_clk == NULL) {
-		gpc_dvfs_clk = clk_get(NULL, "gpc_dvfs");
-		if (IS_ERR(gpc_dvfs_clk))
-			return;
-		clk_prepare(gpc_dvfs_clk);
-	}
-	clk_enable(gpc_dvfs_clk);
-	mx5_cpu_lp_set(WAIT_UNCLOCKED_POWER_OFF);
-	if (!tzic_enable_wake())
-		cpu_do_idle();
-	clk_disable(gpc_dvfs_clk);
-}
-
 /*
  * Define the MX50 memory map.
  */
@@ -105,7 +86,6 @@ void __init imx51_init_early(void)
 	mxc_set_cpu_type(MXC_CPU_MX51);
 	mxc_iomux_v3_init(MX51_IO_ADDRESS(MX51_IOMUXC_BASE_ADDR));
 	mxc_arch_reset_init(MX51_IO_ADDRESS(MX51_WDOG1_BASE_ADDR));
-	arm_pm_idle = imx5_idle;
 }
 
 void __init imx53_init_early(void)
@@ -241,4 +221,5 @@ void __init imx53_soc_init(void)
 void __init imx51_init_late(void)
 {
 	mx51_neon_fixup();
+	imx51_pm_init();
 }