platform/x86: amd: pmf: Fix STT limits

JIRA: https://issues.redhat.com/browse/RHEL-105420

commit fcf27a6
Author: Mario Limonciello <[email protected]>
Date:   Mon Apr 7 13:18:21 2025 -0500

    platform/x86: amd: pmf: Fix STT limits

    On some platforms it has been observed that STT limits are not being
    applied properly causing poor performance as power limits are set too low.

    STT limits that are sent to the platform are supposed to be in Q8.8
    format.  Convert them before sending.

    Reported-by: Yijun Shen <[email protected]>
    Fixes: 7c45534 ("platform/x86/amd/pmf: Add support for PMF Policy Binary")
    Cc: [email protected]
    Tested-by: Yijun Shen <[email protected]>
    Signed-off-by: Mario Limonciello <[email protected]>
    Acked-by: Shyam Sundar S K <[email protected]>
    Reviewed-by: Ilpo Järvinen <[email protected]>
    Link: https://lore.kernel.org/r/[email protected]
    Signed-off-by: Ilpo Järvinen <[email protected]>

Signed-off-by: David Arcari <[email protected]>

Author: darcari

drivers/platform/x86/amd/pmf/auto-mode.c

@@ -120,9 +120,9 @@ static void amd_pmf_set_automode(struct amd_pmf_dev *dev, int idx,
 	amd_pmf_send_cmd(dev, SET_SPPT_APU_ONLY, false, pwr_ctrl->sppt_apu_only, NULL);
 	amd_pmf_send_cmd(dev, SET_STT_MIN_LIMIT, false, pwr_ctrl->stt_min, NULL);
 	amd_pmf_send_cmd(dev, SET_STT_LIMIT_APU, false,
-			 pwr_ctrl->stt_skin_temp[STT_TEMP_APU], NULL);
+			 fixp_q88_fromint(pwr_ctrl->stt_skin_temp[STT_TEMP_APU]), NULL);
 	amd_pmf_send_cmd(dev, SET_STT_LIMIT_HS2, false,
-			 pwr_ctrl->stt_skin_temp[STT_TEMP_HS2], NULL);
+			 fixp_q88_fromint(pwr_ctrl->stt_skin_temp[STT_TEMP_HS2]), NULL);
 
 	if (is_apmf_func_supported(dev, APMF_FUNC_SET_FAN_IDX))
 		apmf_update_fan_idx(dev, config_store.mode_set[idx].fan_control.manual,

drivers/platform/x86/amd/pmf/cnqf.c

@@ -81,10 +81,10 @@ static int amd_pmf_set_cnqf(struct amd_pmf_dev *dev, int src, int idx,
 	amd_pmf_send_cmd(dev, SET_SPPT, false, pc->sppt, NULL);
 	amd_pmf_send_cmd(dev, SET_SPPT_APU_ONLY, false, pc->sppt_apu_only, NULL);
 	amd_pmf_send_cmd(dev, SET_STT_MIN_LIMIT, false, pc->stt_min, NULL);
-	amd_pmf_send_cmd(dev, SET_STT_LIMIT_APU, false, pc->stt_skin_temp[STT_TEMP_APU],
-			 NULL);
-	amd_pmf_send_cmd(dev, SET_STT_LIMIT_HS2, false, pc->stt_skin_temp[STT_TEMP_HS2],
-			 NULL);
+	amd_pmf_send_cmd(dev, SET_STT_LIMIT_APU, false,
+			 fixp_q88_fromint(pc->stt_skin_temp[STT_TEMP_APU]), NULL);
+	amd_pmf_send_cmd(dev, SET_STT_LIMIT_HS2, false,
+			 fixp_q88_fromint(pc->stt_skin_temp[STT_TEMP_HS2]), NULL);
 
 	if (is_apmf_func_supported(dev, APMF_FUNC_SET_FAN_IDX))
 		apmf_update_fan_idx(dev,

drivers/platform/x86/amd/pmf/core.c

@@ -176,6 +176,20 @@ static void __maybe_unused amd_pmf_dump_registers(struct amd_pmf_dev *dev)
 	dev_dbg(dev->dev, "AMD_PMF_REGISTER_MESSAGE:%x\n", value);
 }
 
+/**
+ * fixp_q88_fromint: Convert integer to Q8.8
+ * @val: input value
+ *
+ * Converts an integer into binary fixed point format where 8 bits
+ * are used for integer and 8 bits are used for the decimal.
+ *
+ * Return: unsigned integer converted to Q8.8 format
+ */
+u32 fixp_q88_fromint(u32 val)
+{
+	return val << 8;
+}
+
 int amd_pmf_send_cmd(struct amd_pmf_dev *dev, u8 message, bool get, u32 arg, u32 *data)
 {
 	int rc;

drivers/platform/x86/amd/pmf/pmf.h

@@ -777,6 +777,7 @@ int apmf_install_handler(struct amd_pmf_dev *pmf_dev);
 int apmf_os_power_slider_update(struct amd_pmf_dev *dev, u8 flag);
 int amd_pmf_set_dram_addr(struct amd_pmf_dev *dev, bool alloc_buffer);
 int amd_pmf_notify_sbios_heartbeat_event_v2(struct amd_pmf_dev *dev, u8 flag);
+u32 fixp_q88_fromint(u32 val);
 
 /* SPS Layer */
 int amd_pmf_get_pprof_modes(struct amd_pmf_dev *pmf);

drivers/platform/x86/amd/pmf/sps.c

@@ -198,9 +198,11 @@ static void amd_pmf_update_slider_v2(struct amd_pmf_dev *dev, int idx)
 	amd_pmf_send_cmd(dev, SET_STT_MIN_LIMIT, false,
 			 apts_config_store.val[idx].stt_min_limit, NULL);
 	amd_pmf_send_cmd(dev, SET_STT_LIMIT_APU, false,
-			 apts_config_store.val[idx].stt_skin_temp_limit_apu, NULL);
+			 fixp_q88_fromint(apts_config_store.val[idx].stt_skin_temp_limit_apu),
+			 NULL);
 	amd_pmf_send_cmd(dev, SET_STT_LIMIT_HS2, false,
-			 apts_config_store.val[idx].stt_skin_temp_limit_hs2, NULL);
+			 fixp_q88_fromint(apts_config_store.val[idx].stt_skin_temp_limit_hs2),
+			 NULL);
 }
 
 void amd_pmf_update_slider(struct amd_pmf_dev *dev, bool op, int idx,
@@ -217,9 +219,11 @@ void amd_pmf_update_slider(struct amd_pmf_dev *dev, bool op, int idx,
 		amd_pmf_send_cmd(dev, SET_STT_MIN_LIMIT, false,
 				 config_store.prop[src][idx].stt_min, NULL);
 		amd_pmf_send_cmd(dev, SET_STT_LIMIT_APU, false,
-				 config_store.prop[src][idx].stt_skin_temp[STT_TEMP_APU], NULL);
+				 fixp_q88_fromint(config_store.prop[src][idx].stt_skin_temp[STT_TEMP_APU]),
+				 NULL);
 		amd_pmf_send_cmd(dev, SET_STT_LIMIT_HS2, false,
-				 config_store.prop[src][idx].stt_skin_temp[STT_TEMP_HS2], NULL);
+				 fixp_q88_fromint(config_store.prop[src][idx].stt_skin_temp[STT_TEMP_HS2]),
+				 NULL);
 	} else if (op == SLIDER_OP_GET) {
 		amd_pmf_send_cmd(dev, GET_SPL, true, ARG_NONE, &table->prop[src][idx].spl);
 		amd_pmf_send_cmd(dev, GET_FPPT, true, ARG_NONE, &table->prop[src][idx].fppt);

drivers/platform/x86/amd/pmf/tee-if.c

@@ -123,15 +123,17 @@ static void amd_pmf_apply_policies(struct amd_pmf_dev *dev, struct ta_pmf_enact_
 
 		case PMF_POLICY_STT_SKINTEMP_APU:
 			if (dev->prev_data->stt_skintemp_apu != val) {
-				amd_pmf_send_cmd(dev, SET_STT_LIMIT_APU, false, val, NULL);
+				amd_pmf_send_cmd(dev, SET_STT_LIMIT_APU, false,
+						 fixp_q88_fromint(val), NULL);
 				dev_dbg(dev->dev, "update STT_SKINTEMP_APU: %u\n", val);
 				dev->prev_data->stt_skintemp_apu = val;
 			}
 			break;
 
 		case PMF_POLICY_STT_SKINTEMP_HS2:
 			if (dev->prev_data->stt_skintemp_hs2 != val) {
-				amd_pmf_send_cmd(dev, SET_STT_LIMIT_HS2, false, val, NULL);
+				amd_pmf_send_cmd(dev, SET_STT_LIMIT_HS2, false,
+						 fixp_q88_fromint(val), NULL);
 				dev_dbg(dev->dev, "update STT_SKINTEMP_HS2: %u\n", val);
 				dev->prev_data->stt_skintemp_hs2 = val;
 			}