Re: [PATCH v5 4/5] arm64: add support for ACPI Low Power Idle(LPI)

[Sudeep Holla]

On 13/06/16 05:47, Sajjan, Vikas C wrote:

Hi Sudeep,

[...]

--- a/drivers/firmware/psci.c
+++ b/drivers/firmware/psci.c
@@ -13,6 +13,7 @@

  #define pr_fmt(fmt) "psci: " fmt

+#include <linux/acpi.h>
  #include <linux/arm-smccc.h>
  #include <linux/cpuidle.h>
  #include <linux/errno.h>
@@ -310,11 +311,66 @@ static int psci_dt_cpu_init_idle(struct device_node 
*cpu_node, int cpu)
        return ret;
  }

+#ifdef CONFIG_ACPI
+#include <acpi/processor.h>
+
+static int __maybe_unused psci_acpi_cpu_init_idle(unsigned int cpu) {
+       int i, count;
+       u32 *psci_states;
+       struct acpi_processor *pr;
+       struct acpi_lpi_state *lpi;
+
+       pr = per_cpu(processors, cpu);
+       if (unlikely(!pr || !pr->flags.has_lpi))

Any particular reason for _not_ considering CST flag here.
Or you are planning to add CST support in some other patch set.

Are you referring the old C-state objects ? We don't support them on
ARM64. Only LPIs are support. The ARM FFH is not defined for CST, only
for LPIs.

--
Regards,
Sudeep