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| author | Joseph Lo <josephl@nvidia.com> | 2013-08-12 17:40:06 +0800 |
|---|---|---|
| committer | Stephen Warren <swarren@nvidia.com> | 2013-08-12 13:30:12 -0600 |
| commit | e9f624499cc84a625648ccfbd550b74d17d52fb2 (patch) | |
| tree | 5076ecac1bd3a76a902e27535d5bd499d25deb73 /arch/arm/mach-tegra/pm.c | |
| parent | 731a9274382f8e6f4961df79fe12ebcc5431a5df (diff) | |
| download | linux-e9f624499cc84a625648ccfbd550b74d17d52fb2.tar.gz linux-e9f624499cc84a625648ccfbd550b74d17d52fb2.tar.bz2 linux-e9f624499cc84a625648ccfbd550b74d17d52fb2.zip | |
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>
Diffstat (limited to 'arch/arm/mach-tegra/pm.c')
| -rw-r--r-- | arch/arm/mach-tegra/pm.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/arch/arm/mach-tegra/pm.c b/arch/arm/mach-tegra/pm.c index e718350367e4..eaf6bd372ee1 100644 --- a/arch/arm/mach-tegra/pm.c +++ b/arch/arm/mach-tegra/pm.c @@ -215,7 +215,9 @@ static bool tegra_lp1_iram_hook(void) tegra20_lp1_iram_hook(); break; case TEGRA30: - if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC)) + case TEGRA114: + if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC) || + IS_ENABLED(CONFIG_ARCH_TEGRA_114_SOC)) tegra30_lp1_iram_hook(); break; default: @@ -241,7 +243,9 @@ static bool tegra_sleep_core_init(void) tegra20_sleep_core_init(); break; case TEGRA30: - if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC)) + case TEGRA114: + if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC) || + IS_ENABLED(CONFIG_ARCH_TEGRA_114_SOC)) tegra30_sleep_core_init(); break; default: |