[PATCH 10/12] platform/x86: ISST: Add SST-BF support via TPMI

[Srinivas Pandruvada]

The Intel Speed Select Technology - Base Frequency (SST-BF) feature lets
the user control base frequency. If some critical workload threads demand
constant high guaranteed performance, then this feature can be used to
execute the thread at higher base frequency on specific sets of CPUs
(high priority CPUs) at the cost of lower base frequency (low priority
CPUs) on other CPUs.

Two new IOCTLs are added:
ISST_IF_GET_BASE_FREQ_INFO : Get frequency information for high and
				low priority CPUs
ISST_IF_GET_BASE_FREQ_CPU_MASK : CPUs capable of higher frequency

Once an instance is identified, read or write from correct MMIO
offset for a given field as defined in the specification.

For details on SST-BF operations using intel-speed-selet utility,
refer to:
Documentation/admin-guide/pm/intel-speed-select.rst
under the kernel documentation

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
---
 .../intel/speed_select_if/isst_tpmi_core.c    | 87 +++++++++++++++++++
 1 file changed, 87 insertions(+)

diff --git a/drivers/platform/x86/intel/speed_select_if/isst_tpmi_core.c b/drivers/platform/x86/intel/speed_select_if/isst_tpmi_core.c
index 3926e0f85f8f..fe7c364a8d0b 100644
--- a/drivers/platform/x86/intel/speed_select_if/isst_tpmi_core.c
+++ b/drivers/platform/x86/intel/speed_select_if/isst_tpmi_core.c
@@ -1014,6 +1014,87 @@ static int isst_if_get_perf_level_mask(void __user *argp)
 	return 0;
 }
 
+#define SST_BF_INFO_0_OFFSET	0
+#define SST_BF_INFO_1_OFFSET	8
+
+#define SST_BF_P1_HIGH_START	13
+#define SST_BF_P1_HIGH_WIDTH	8
+
+#define SST_BF_P1_LOW_START	21
+#define SST_BF_P1_LOW_WIDTH	8
+
+#define SST_BF_T_PROHOT_START	38
+#define SST_BF_T_PROHOT_WIDTH	8
+
+#define SST_BF_TDP_START	46
+#define SST_BF_TDP_WIDTH	15
+
+static int isst_if_get_base_freq_info(void __user *argp)
+{
+	static struct isst_base_freq_info base_freq;
+	struct tpmi_per_power_domain_info *power_domain_info;
+
+	if (copy_from_user(&base_freq, argp, sizeof(base_freq)))
+		return -EFAULT;
+
+	power_domain_info = get_instance(base_freq.socket_id, base_freq.power_domain_id);
+	if (!power_domain_info)
+		return -EINVAL;
+
+	if (base_freq.level > power_domain_info->max_level)
+		return -EINVAL;
+
+	_read_bf_level_info("p1_high", base_freq.high_base_freq_mhz, base_freq.level,
+			    SST_BF_INFO_0_OFFSET, SST_BF_P1_HIGH_START, SST_BF_P1_HIGH_WIDTH,
+			    SST_MUL_FACTOR_FREQ)
+	_read_bf_level_info("p1_low", base_freq.low_base_freq_mhz, base_freq.level,
+			    SST_BF_INFO_0_OFFSET, SST_BF_P1_LOW_START, SST_BF_P1_LOW_WIDTH,
+			    SST_MUL_FACTOR_FREQ)
+	_read_bf_level_info("BF-TJ", base_freq.tjunction_max_c, base_freq.level,
+			    SST_BF_INFO_0_OFFSET, SST_BF_T_PROHOT_START, SST_BF_T_PROHOT_WIDTH,
+			    SST_MUL_FACTOR_NONE)
+	_read_bf_level_info("BF-tdp", base_freq.thermal_design_power_w, base_freq.level,
+			    SST_BF_INFO_0_OFFSET, SST_BF_TDP_START, SST_BF_TDP_WIDTH,
+			    SST_MUL_FACTOR_NONE)
+	base_freq.thermal_design_power_w /= 8; /*unit = 1/8th watt*/
+
+	if (copy_to_user(argp, &base_freq, sizeof(base_freq)))
+		return -EFAULT;
+
+	return 0;
+}
+
+#define P1_HI_CORE_MASK_START	0
+#define P1_HI_CORE_MASK_WIDTH	64
+
+static int isst_if_get_base_freq_mask(void __user *argp)
+{
+	static struct isst_perf_level_cpu_mask cpumask;
+	struct tpmi_per_power_domain_info *power_domain_info;
+	u64 mask;
+
+	if (copy_from_user(&cpumask, argp, sizeof(cpumask)))
+		return -EFAULT;
+
+	power_domain_info = get_instance(cpumask.socket_id, cpumask.power_domain_id);
+	if (!power_domain_info)
+		return -EINVAL;
+
+	_read_bf_level_info("BF-cpumask", mask, cpumask.level, SST_BF_INFO_1_OFFSET,
+			    P1_HI_CORE_MASK_START, P1_HI_CORE_MASK_WIDTH,
+			    SST_MUL_FACTOR_NONE)
+
+	cpumask.mask = mask;
+
+	if (!cpumask.punit_cpu_map)
+		return -EOPNOTSUPP;
+
+	if (copy_to_user(argp, &cpumask, sizeof(cpumask)))
+		return -EFAULT;
+
+	return 0;
+}
+
 static int isst_if_get_tpmi_instance_count(void __user *argp)
 {
 	struct isst_tpmi_instance_count tpmi_inst;
@@ -1079,6 +1160,12 @@ static long isst_if_def_ioctl(struct file *file, unsigned int cmd,
 	case ISST_IF_GET_PERF_LEVEL_CPU_MASK:
 		ret = isst_if_get_perf_level_mask(argp);
 		break;
+	case ISST_IF_GET_BASE_FREQ_INFO:
+		ret = isst_if_get_base_freq_info(argp);
+		break;
+	case ISST_IF_GET_BASE_FREQ_CPU_MASK:
+		ret = isst_if_get_base_freq_mask(argp);
+		break;
 	default:
 		break;
 	}
-- 
2.39.1