On Wed, Sep 07, 2011 at 10:38:10AM +0530, Shilimkar, Santosh wrote:

On Wed, Sep 7, 2011 at 10:11 AM, Shawn Guo [off-list ref] wrote:

quoted

On Tue, Sep 06, 2011 at 08:53:07PM +0200, Arnd Bergmann wrote:

quoted

On Tuesday 06 September 2011 17:58:38 Shawn Guo wrote:

quoted

It adds smp and cpu hotplug support for imx6q.
+static u32 twd_saved_regs[4];
+static int twd_irq;
+
+/*
+ * Resuming from ARM Dormant/Shutdown mode, the boot procedure will
+ * re-setup local timer for secondary cores. ?For primary core, it
+ * has to take care of itself with the following pair of functions
+ * during suspend/resume.
+ */
+void imx_local_timer_pre_suspend(void)
+{
+ ? twd_saved_regs[0] = __raw_readl(twd_base + TWD_TIMER_LOAD);
+ ? twd_saved_regs[1] = __raw_readl(twd_base + TWD_TIMER_COUNTER);
+ ? twd_saved_regs[2] = __raw_readl(twd_base + TWD_TIMER_CONTROL);
+ ? twd_saved_regs[3] = __raw_readl(twd_base + TWD_TIMER_INTSTAT);
+}
+
+void imx_local_timer_post_resume(void)
+{
+ ? __raw_writel(twd_saved_regs[0], twd_base + TWD_TIMER_LOAD);
+ ? __raw_writel(twd_saved_regs[1], twd_base + TWD_TIMER_COUNTER);
+ ? __raw_writel(twd_saved_regs[2], twd_base + TWD_TIMER_CONTROL);
+ ? __raw_writel(twd_saved_regs[3], twd_base + TWD_TIMER_INTSTAT);
+
+ ? gic_enable_ppi(twd_irq);
+}

readl_relaxed()?

Ok. ?You get the best judgement on this.

You don't have to save local timer registers any more. The local timer
is always re-configued and this is already handled in common kernel.

You can drop above change and test your patches. I am sure they will
still work.

Ah, yes.  This registers saving/restoring was added together with
cpu0 twd_irq enabling when I use git_reinit() approach, which turns
out to be unnecessary.  This pair of imx_local_timer_pre_suspend/resume
can totally be removed now, since "CPU PM notifiers" patches come to
play.

Thanks for catching this, Santosh.

-- 
Regards,
Shawn