platform/x86: amd-pmc: Drop CPU QoS workaround

A workaround was previously introduced as part of commit 646f429ec2de
("platform/x86: amd-pmc: Set QOS during suspend on CZN w/ timer wakeup")
to prevent CPUs from going into the deepest state during the execution
of the `noirq` stage of `amd_pmc`.  As `amd_pmc` has been pushed to the
last step for suspend on AMD platforms, this workaround is no longer
necessary.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://lore.kernel.org/r/20220317141445.6498-4-mario.limonciello@amd.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Author: superm1

drivers/platform/x86/amd-pmc.c

@@ -21,7 +21,6 @@
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
-#include <linux/pm_qos.h>
 #include <linux/rtc.h>
 #include <linux/suspend.h>
 #include <linux/seq_file.h>
@@ -96,9 +95,6 @@
 #define PMC_MSG_DELAY_MIN_US		50
 #define RESPONSE_REGISTER_LOOP_MAX	20000
 
-/* QoS request for letting CPUs in idle states, but not the deepest */
-#define AMD_PMC_MAX_IDLE_STATE_LATENCY	3
-
 #define SOC_SUBSYSTEM_IP_MAX	12
 #define DELAY_MIN_US		2000
 #define DELAY_MAX_US		3000
@@ -153,7 +149,6 @@ struct amd_pmc_dev {
 	struct device *dev;
 	struct pci_dev *rdev;
 	struct mutex lock; /* generic mutex lock */
-	struct pm_qos_request amd_pmc_pm_qos_req;
 #if IS_ENABLED(CONFIG_DEBUG_FS)
 	struct dentry *dbgfs_dir;
 #endif /* CONFIG_DEBUG_FS */
@@ -628,14 +623,6 @@ static int amd_pmc_verify_czn_rtc(struct amd_pmc_dev *pdev, u32 *arg)
 	rc = rtc_alarm_irq_enable(rtc_device, 0);
 	dev_dbg(pdev->dev, "wakeup timer programmed for %lld seconds\n", duration);
 
-	/*
-	 * Prevent CPUs from getting into deep idle states while sending OS_HINT
-	 * which is otherwise generally safe to send when at least one of the CPUs
-	 * is not in deep idle states.
-	 */
-	cpu_latency_qos_update_request(&pdev->amd_pmc_pm_qos_req, AMD_PMC_MAX_IDLE_STATE_LATENCY);
-	wake_up_all_idle_cpus();
-
 	return rc;
 }
 
@@ -655,7 +642,7 @@ static void amd_pmc_s2idle_prepare(void)
 		rc = amd_pmc_verify_czn_rtc(pdev, &arg);
 		if (rc) {
 			dev_err(pdev->dev, "failed to set RTC: %d\n", rc);
-			goto fail;
+			return;
 		}
 	}
 
@@ -665,20 +652,13 @@ static void amd_pmc_s2idle_prepare(void)
 	rc = amd_pmc_send_cmd(pdev, arg, NULL, msg, 0);
 	if (rc) {
 		dev_err(pdev->dev, "suspend failed: %d\n", rc);
-		goto fail;
+		return;
 	}
 
 	if (enable_stb)
 		rc = amd_pmc_write_stb(pdev, AMD_PMC_STB_PREDEF);
-	if (rc) {
+	if (rc)
 		dev_err(pdev->dev, "error writing to STB: %d\n", rc);
-		goto fail;
-	}
-	return;
-fail:
-	if (pdev->cpu_id == AMD_CPU_ID_CZN)
-		cpu_latency_qos_update_request(&pdev->amd_pmc_pm_qos_req,
-						PM_QOS_DEFAULT_VALUE);
 }
 
 static void amd_pmc_s2idle_restore(void)
@@ -704,11 +684,6 @@ static void amd_pmc_s2idle_restore(void)
 	if (rc)
 		dev_err(pdev->dev, "error writing to STB: %d\n", rc);
 
-	/* Restore the QoS request back to defaults if it was set */
-	if (pdev->cpu_id == AMD_CPU_ID_CZN)
-		cpu_latency_qos_update_request(&pdev->amd_pmc_pm_qos_req,
-						PM_QOS_DEFAULT_VALUE);
-
 	/* Notify on failed entry */
 	amd_pmc_validate_deepest(pdev);
 }
@@ -887,7 +862,6 @@ static int amd_pmc_probe(struct platform_device *pdev)
 		dev_warn(dev->dev, "failed to register LPS0 sleep handler, expect increased power consumption\n");
 
 	amd_pmc_dbgfs_register(dev);
-	cpu_latency_qos_add_request(&dev->amd_pmc_pm_qos_req, PM_QOS_DEFAULT_VALUE);
 	return 0;
 
 err_pci_dev_put: