[PATCH v5] intel_idle: Add Comet Lake support

[Harry Pan]

Add built-in idle states table for Comet Lake.

This patch also respects the exposed ACPI _CST objects in platform firmware
to disable those non-matching C-state by default, defer its enabling to the
userspace through sysfs.

Summary:
 - With built-in table and without _CST table, all C-states are enabled
 - With both built-in and _CST tables, matching C-states are enabled

Signed-off-by: Harry Pan <harry.pan@xxxxxxxxx>

---

 drivers/idle/intel_idle.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index d55606608ac8..49b385c36eea 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -1067,6 +1067,12 @@ static const struct idle_cpu idle_cpu_dnv = {
 	.use_acpi = true,
 };
 
+static const struct idle_cpu idle_cpu_cml = {
+	.state_table = skl_cstates,
+	.disable_promotion_to_c1e = true,
+	.use_acpi = true,
+};
+
 static const struct x86_cpu_id intel_idle_ids[] __initconst = {
 	INTEL_CPU_FAM6(NEHALEM_EP,		idle_cpu_nhx),
 	INTEL_CPU_FAM6(NEHALEM,			idle_cpu_nehalem),
@@ -1105,6 +1111,8 @@ static const struct x86_cpu_id intel_idle_ids[] __initconst = {
 	INTEL_CPU_FAM6(ATOM_GOLDMONT_PLUS,	idle_cpu_bxt),
 	INTEL_CPU_FAM6(ATOM_GOLDMONT_D,		idle_cpu_dnv),
 	INTEL_CPU_FAM6(ATOM_TREMONT_D,		idle_cpu_dnv),
+	INTEL_CPU_FAM6(COMETLAKE_L,		idle_cpu_cml),
+	INTEL_CPU_FAM6(COMETLAKE,		idle_cpu_cml),
 	{}
 };
 
-- 
2.24.1