Re: [PATCH 195/228] cpufreq: kirkwood: remove calls to cpufreq_notify_transition()

On 13 September 2013 21:48, Andrew Lunn andrew@lunn.ch wrote:

On Fri, Sep 13, 2013 at 06:32:21PM +0530, Viresh Kumar wrote:

...

• if (freqs.old != freqs.new) {
  

•         local_irq_disable();
  

•         /* Disable interrupts to the CPU */
  

•         reg = readl_relaxed(priv.base);
  

•         reg |= CPU_SW_INT_BLK;
  

•         writel_relaxed(reg, priv.base);
  

•         switch (state) {
  

•         case STATE_CPU_FREQ:
  

•                 clk_disable(priv.powersave_clk);
  

•                 break;
  

•         case STATE_DDR_FREQ:
  

•                 clk_enable(priv.powersave_clk);
  

•                 break;
  

•         }
  

Hi Viresh

I see you removed the test that the old and the new frequency are different. Is this guaranteed by the core? Because if not, you can lockup the CPU. The call to cpu_do_idle() will never return.

Yes, that's guaranteed by core: patch 181..