ARM: tegra20: cpuidle: add powered-down state for secondary CPU

The powered-down state of Tegra20 requires power gating both CPU cores.
When the secondary CPU requests to enter powered-down state, it saves
its own contexts and then enters WFI. The Tegra20 had a limition to
power down both CPU cores. The secondary CPU must waits for CPU0 in
powered-down state too. If the secondary CPU be woken up before CPU0
entering powered-down state, then it needs to restore its CPU states
and waits for next chance.

Be aware of that, you may see the legacy power state "LP2" in the code
which is exactly the same meaning of "CPU power down".

Based on the work by:
Colin Cross <ccross@android.com>
Gary King <gking@nvidia.com>

Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
This commit is contained in:
Joseph Lo
2013-01-15 22:10:38 +00:00
committed by Stephen Warren
parent d4b92fb253
commit 5c1350bdfc
4 changed files with 259 additions and 4 deletions

View File

@@ -25,6 +25,19 @@
+ IO_PPSB_VIRT)
#define TEGRA_CLK_RESET_VIRT (TEGRA_CLK_RESET_BASE - IO_PPSB_PHYS \
+ IO_PPSB_VIRT)
#define TEGRA_PMC_VIRT (TEGRA_PMC_BASE - IO_APB_PHYS + IO_APB_VIRT)
/* PMC_SCRATCH37-39 and 41 are used for tegra_pen_lock and idle */
#define PMC_SCRATCH37 0x130
#define PMC_SCRATCH38 0x134
#define PMC_SCRATCH39 0x138
#define PMC_SCRATCH41 0x140
#ifdef CONFIG_ARCH_TEGRA_2x_SOC
#define CPU_RESETTABLE 2
#define CPU_RESETTABLE_SOON 1
#define CPU_NOT_RESETTABLE 0
#endif
#ifdef __ASSEMBLY__
/* returns the offset of the flow controller halt register for a cpu */
@@ -104,6 +117,8 @@ exit_l2_resume:
.endm
#endif /* CONFIG_CACHE_L2X0 */
#else
void tegra_pen_lock(void);
void tegra_pen_unlock(void);
void tegra_resume(void);
int tegra_sleep_cpu_finish(unsigned long);
void tegra_disable_clean_inv_dcache(void);
@@ -116,6 +131,14 @@ static inline void tegra20_hotplug_init(void) {}
static inline void tegra30_hotplug_init(void) {}
#endif
void tegra20_cpu_clear_resettable(void);
#ifdef CONFIG_ARCH_TEGRA_2x_SOC
void tegra20_cpu_set_resettable_soon(void);
#else
static inline void tegra20_cpu_set_resettable_soon(void) {}
#endif
int tegra20_sleep_cpu_secondary_finish(unsigned long);
int tegra30_sleep_cpu_secondary_finish(unsigned long);
void tegra30_tear_down_cpu(void);