[PATCH] powercap/rapl: add support for ValleyView Soc

[Jacob Pan <jacob.jun.pan@linux.intel.com>]

This patch adds support for RAPL on Intel ValleyView based SoC
platforms, such as Baytrail.

Besides adding CPU ID, special energy unit encoding is handled
for ValleyView.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
---
 drivers/powercap/intel_rapl.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/powercap/intel_rapl.c b/drivers/powercap/intel_rapl.c
index 2a786c5..3c67683 100644
--- a/drivers/powercap/intel_rapl.c
+++ b/drivers/powercap/intel_rapl.c
@@ -833,6 +833,11 @@ static int rapl_write_data_raw(struct rapl_domain *rd,
 	return 0;
 }
 
+static const struct x86_cpu_id energy_unit_quirk_ids[] = {
+	{ X86_VENDOR_INTEL, 6, 0x37},/* VLV */
+	{}
+};
+
 static int rapl_check_unit(struct rapl_package *rp, int cpu)
 {
 	u64 msr_val;
@@ -853,8 +858,11 @@ static int rapl_check_unit(struct rapl_package *rp, int cpu)
 	 * time unit: 1/time_unit_divisor Seconds
 	 */
 	value = (msr_val & ENERGY_UNIT_MASK) >> ENERGY_UNIT_OFFSET;
-	rp->energy_unit_divisor = 1 << value;
-
+	/* some CPUs have different way to calculate energy unit */
+	if (x86_match_cpu(energy_unit_quirk_ids))
+		rp->energy_unit_divisor = 1000000 / (1 << value);
+	else
+		rp->energy_unit_divisor = 1 << value;
 
 	value = (msr_val & POWER_UNIT_MASK) >> POWER_UNIT_OFFSET;
 	rp->power_unit_divisor = 1 << value;
@@ -941,6 +949,7 @@ static void package_power_limit_irq_restore(int package_id)
 static const struct x86_cpu_id rapl_ids[] = {
 	{ X86_VENDOR_INTEL, 6, 0x2a},/* SNB */
 	{ X86_VENDOR_INTEL, 6, 0x2d},/* SNB EP */
+	{ X86_VENDOR_INTEL, 6, 0x37},/* VLV */
 	{ X86_VENDOR_INTEL, 6, 0x3a},/* IVB */
 	{ X86_VENDOR_INTEL, 6, 0x45},/* HSW */
 	/* TODO: Add more CPU IDs after testing */
-- 
1.8.1.2