[PATCHv3] ARM: imx: Add support for low power suspend on MX51.

[Nguyen Dinh-R00091]

Hi Sascha/Uwe,

I was wondering if you had time to digest this patch?

Thanks,
Dinh

>-----Original Message-----
>From: Nguyen Dinh-R00091
>Sent: Wednesday, November 10, 2010 2:07 PM
>To: linux-kernel at vger.kernel.org
>Cc: linux-arm-kernel at lists.infradead.org; linux at arm.linux.org.uk;
s.hauer at pengutronix.de; u.kleine-
>koenig at pengutronix.de; amit.kucheria at canonical.com; eric at eukrea.com;
Nguyen Dinh-R00091
>Subject: [PATCHv3] ARM: imx: Add support for low power suspend on MX51.
>
>From: Dinh Nguyen <Dinh.Nguyen at freescale.com>
>
>Adds initial low power suspend functionality to MX51.
>Supports "mem" and "standby" modes.
>
>Signed-off-by: Dinh Nguyen <Dinh.Nguyen at freescale.com>
>---
> arch/arm/mach-mx5/Makefile           |    1 +
> arch/arm/mach-mx5/pm.c               |   70
++++++++++++++++++++++++++++++++++
> arch/arm/plat-mxc/include/mach/mxc.h |    1 +
> 3 files changed, 72 insertions(+), 0 deletions(-)
> create mode 100644 arch/arm/mach-mx5/pm.c
>
>diff --git a/arch/arm/mach-mx5/Makefile b/arch/arm/mach-mx5/Makefile
>index 462f177..25b44d1 100644
>--- a/arch/arm/mach-mx5/Makefile
>+++ b/arch/arm/mach-mx5/Makefile
>@@ -5,6 +5,7 @@
> # Object file lists.
> obj-y   := cpu.o mm.o clock-mx51.o devices.o
>
>+obj-$(CONFIG_PM) += pm.o
> obj-$(CONFIG_CPU_FREQ_IMX)    += cpu_op-mx51.o
> obj-$(CONFIG_MACH_MX51_BABBAGE) += board-mx51_babbage.o
> obj-$(CONFIG_MACH_MX51_3DS) += board-mx51_3ds.o
>diff --git a/arch/arm/mach-mx5/pm.c b/arch/arm/mach-mx5/pm.c
>new file mode 100644
>index 0000000..417cce1
>--- /dev/null
>+++ b/arch/arm/mach-mx5/pm.c
>@@ -0,0 +1,70 @@
>+/*
>+ *  Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights
Reserved.
>+ *
>+ * The code contained herein is licensed under the GNU General Public
>+ * License. You may obtain a copy of the GNU General Public License
>+ * Version 2 or later at the following locations:
>+ *
>+ * http://www.opensource.org/licenses/gpl-license.html
>+ * http://www.gnu.org/copyleft/gpl.html
>+ */
>+#include <linux/suspend.h>
>+#include <asm/mach/map.h>
>+#include <mach/system.h>
>+#include "crm_regs.h"
>+
>+static int mx5_suspend_enter(suspend_state_t state)
>+{
>+	u32 plat_lpc, arm_srpgcr, ccm_clpcr;
>+
>+	/* always allow platform to issue a deep sleep mode request */
>+	ccm_clpcr = __raw_readl(MXC_CCM_CLPCR) &
~(MXC_CCM_CLPCR_LPM_MASK);
>+
>+	switch (state) {
>+	case PM_SUSPEND_MEM:
>+		ccm_clpcr |= (0x2 << MXC_CCM_CLPCR_LPM_OFFSET);
>+		ccm_clpcr |= (0x3 << MXC_CCM_CLPCR_STBY_COUNT_OFFSET);
>+		ccm_clpcr |= MXC_CCM_CLPCR_VSTBY;
>+		ccm_clpcr |= MXC_CCM_CLPCR_SBYOS;
>+		break;
>+	case PM_SUSPEND_STANDBY:
>+		ccm_clpcr |= (0x1 << MXC_CCM_CLPCR_LPM_OFFSET);
>+		ccm_clpcr &= ~MXC_CCM_CLPCR_VSTBY;
>+		ccm_clpcr &= ~MXC_CCM_CLPCR_SBYOS;
>+		break;
>+	default:
>+		return -EINVAL;
>+	}
>+
>+	plat_lpc |= MXC_CORTEXA8_PLAT_LPC_DSM
>+		    | MXC_CORTEXA8_PLAT_LPC_DBG_DSM;
>+	arm_srpgcr |= MXC_SRPGCR_PCR;
>+
>+	__raw_writel(plat_lpc, MXC_CORTEXA8_PLAT_LPC);
>+	__raw_writel(arm_srpgcr, MXC_SRPG_ARM_SRPGCR);
>+	__raw_writel(ccm_clpcr, MXC_CCM_CLPCR);
>+
>+	if (tzic_enable_wake(0) != 0)
>+		return -EAGAIN;
>+
>+	cpu_do_idle();
>+	return 0;
>+}
>+
>+static int mx5_pm_valid(suspend_state_t state)
>+{
>+	return (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX);
>+}
>+
>+static const struct platform_suspend_ops mx5_suspend_ops = {
>+	.valid = mx5_pm_valid,
>+	.enter = mx5_suspend_enter,
>+};
>+
>+static int __init mx5_pm_init(void)
>+{
>+	if (cpu_is_mx51())
>+		suspend_set_ops(&mx5_suspend_ops);
>+	return 0;
>+}
>+device_initcall(mx5_pm_init);
>diff --git a/arch/arm/plat-mxc/include/mach/mxc.h
b/arch/arm/plat-mxc/include/mach/mxc.h
>index a42c720..dafacfd 100644
>--- a/arch/arm/plat-mxc/include/mach/mxc.h
>+++ b/arch/arm/plat-mxc/include/mach/mxc.h
>@@ -37,6 +37,7 @@
>
> #ifndef __ASSEMBLY__
> extern unsigned int __mxc_cpu_type;
>+int tzic_enable_wake(int is_idle);
> #endif
>
> #ifdef CONFIG_ARCH_MX1
>--
>1.6.0.4