ARM: tegra: add LP1 suspend support for Tegra114

The LP1 suspend mode will power off the CPU, clock gated the PLLs and put
SDRAM to self-refresh mode. Any interrupt can wake up device from LP1. The
sequence when LP1 suspending:

* tunning off L1 data cache and the MMU
* storing some EMC registers, DPD (deep power down) status, clk source of
  mselect and SCLK burst policy
* putting SDRAM into self-refresh
* switching CPU to CLK_M (12MHz OSC)
* tunning off PLLM, PLLP, PLLA, PLLC and PLLX
* switching SCLK to CLK_S (32KHz OSC)
* shutting off the CPU rail

The sequence of LP1 resuming:

* re-enabling PLLM, PLLP, PLLA, PLLC and PLLX
* restoring the clk source of mselect and SCLK burst policy
* setting up CCLK burst policy to PLLX
* restoring DPD status and some EMC registers
* resuming SDRAM to normal mode
* jumping to the "tegra_resume" from PMC_SCRATCH41

Due to the SDRAM will be put into self-refresh mode, the low level
procedures of LP1 suspending and resuming should be copied to
TEGRA_IRAM_CODE_AREA (TEGRA_IRAM_BASE + SZ_4K) when suspending. Before
restoring the CPU context when resuming, the SDRAM needs to be switched
back to normal mode. And the PLLs need to be re-enabled, SCLK burst policy
be restored. Then jumping to "tegra_resume" that was expected to be stored
in PMC_SCRATCH41 to restore CPU context and back to kernel.

Based on the work by: Bo Yan <byan@nvidia.com>

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile
index a3fe22d5b06a..f4e70631626f 100644
--- a/arch/arm/mach-tegra/Makefile
+++ b/arch/arm/mach-tegra/Makefile
@@ -33,6 +33,7 @@ obj-$(CONFIG_TEGRA_PCI)			+= pcie.o
 
 obj-$(CONFIG_ARCH_TEGRA_114_SOC)        += tegra114_speedo.o
 obj-$(CONFIG_ARCH_TEGRA_114_SOC)        += sleep-tegra30.o
+obj-$(CONFIG_ARCH_TEGRA_114_SOC)        += pm-tegra30.o
 ifeq ($(CONFIG_CPU_IDLE),y)
 obj-$(CONFIG_ARCH_TEGRA_114_SOC)        += cpuidle-tegra114.o
 endif