diff options
| author | Joseph Lo <josephl@nvidia.com> | 2012-10-31 10:41:16 +0100 |
|---|---|---|
| committer | Stephen Warren <swarren@nvidia.com> | 2012-11-15 23:09:21 +0100 |
| commit | d3f293656c07a1147c11e8c8774d7955a903cee0 (patch) | |
| tree | f17307f8dfa112840ba00d05eef16d0d37f9921c /arch/arm/mach-tegra/headsmp.S | |
| parent | ARM: tegra: cpuidle: separate cpuidle driver for different chips (diff) | |
| download | linux-d3f293656c07a1147c11e8c8774d7955a903cee0.tar.xz linux-d3f293656c07a1147c11e8c8774d7955a903cee0.zip | |
ARM: tegra: cpuidle: add CPU resume function
The CPU suspending on Tegra means CPU power gating. We add a resume
function for taking care the CPUs that resume from power gating status.
This function was been hooked to the reset handler. We take care
everything here before go into kernel.
Be aware of that, you may see the legacy power status "LP2" in the code
which is exactly the same meaning of "CPU power down".
Based on the work by:
Scott Williams <scwilliams@nvidia.com>
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>
Diffstat (limited to 'arch/arm/mach-tegra/headsmp.S')
| -rw-r--r-- | arch/arm/mach-tegra/headsmp.S | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/headsmp.S b/arch/arm/mach-tegra/headsmp.S index 93f0370cc95b..82dc84b6b868 100644 --- a/arch/arm/mach-tegra/headsmp.S +++ b/arch/arm/mach-tegra/headsmp.S @@ -68,6 +68,55 @@ ENTRY(tegra_secondary_startup) b secondary_startup ENDPROC(tegra_secondary_startup) +#ifdef CONFIG_PM_SLEEP +/* + * tegra_resume + * + * CPU boot vector when restarting the a CPU following + * an LP2 transition. Also branched to by LP0 and LP1 resume after + * re-enabling sdram. + */ +ENTRY(tegra_resume) + bl v7_invalidate_l1 + /* Enable coresight */ + mov32 r0, 0xC5ACCE55 + mcr p14, 0, r0, c7, c12, 6 + + cpu_id r0 + cmp r0, #0 @ CPU0? + bne cpu_resume @ no + +#ifdef CONFIG_ARCH_TEGRA_3x_SOC + /* Are we on Tegra20? */ + mov32 r6, TEGRA_APB_MISC_BASE + ldr r0, [r6, #APB_MISC_GP_HIDREV] + and r0, r0, #0xff00 + cmp r0, #(0x20 << 8) + beq 1f @ Yes + /* Clear the flow controller flags for this CPU. */ + mov32 r2, TEGRA_FLOW_CTRL_BASE + FLOW_CTRL_CPU0_CSR @ CPU0 CSR + ldr r1, [r2] + /* Clear event & intr flag */ + orr r1, r1, \ + #FLOW_CTRL_CSR_INTR_FLAG | FLOW_CTRL_CSR_EVENT_FLAG + movw r0, #0x0FFD @ enable, cluster_switch, immed, & bitmaps + bic r1, r1, r0 + str r1, [r2] +1: +#endif + +#ifdef CONFIG_HAVE_ARM_SCU + /* enable SCU */ + mov32 r0, TEGRA_ARM_PERIF_BASE + ldr r1, [r0] + orr r1, r1, #1 + str r1, [r0] +#endif + + b cpu_resume +ENDPROC(tegra_resume) +#endif + .align L1_CACHE_SHIFT ENTRY(__tegra_cpu_reset_handler_start) @@ -121,6 +170,17 @@ ENTRY(__tegra_cpu_reset_handler) 1: #endif + /* Waking up from LP2? */ + ldr r9, [r12, #RESET_DATA(MASK_LP2)] + tst r9, r11 @ if in_lp2 + beq __is_not_lp2 + ldr lr, [r12, #RESET_DATA(STARTUP_LP2)] + cmp lr, #0 + bleq __die @ no LP2 startup handler + bx lr + +__is_not_lp2: + #ifdef CONFIG_SMP /* * Can only be secondary boot (initial or hotplug) but CPU 0 |