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path: root/9001-v5.16-s0ix-patch-2022-01-17.patch
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From b4c5953e0377b39c43f0ddb62e1d130495bdf019 Mon Sep 17 00:00:00 2001
From: Scott B <arglebargle@arglebargle.dev>
Date: Mon, 17 Jan 2022 10:09:38 -0800
Subject: [PATCH] v5.16 s0ix patch 2022-01-17

Squashed commit of the following:

commit b7fc459a41bbfbe7268279fb8d0769df37dfb957
Author: Mario Limonciello <mario.limonciello@amd.com>
Date:   Fri Jan 7 10:49:59 2022 -0600

    drm/amd/display: Revert W/A for hard hangs on DCN20/DCN21

    The WA from commit 2a50edbf10c8 ("drm/amd/display: Apply w/a for hard hang
    on HPD") and commit 1bd3bc745e7f ("drm/amd/display: Extend w/a for hard
    hang on HPD to dcn20") causes a regression in s0ix where the system will
    fail to resume properly on many laptops.  Pull the workarounds out to
    avoid that s0ix regression in the common case.  This HPD hang happens with
    an external device and a new W/A will need to be developed for this in the
    future.

    Cc: Kazlauskas Nicholas <Nicholas.Kazlauskas@amd.com>
    Cc: Qingqing Zhuo <qingqing.zhuo@amd.com>
    Reported-by: Scott Bruce <smbruce@gmail.com>
    Reported-by: Chris Hixon <linux-kernel-bugs@hixontech.com>
    Reported-by: spasswolf@web.de
    Link: https://bugzilla.kernel.org/show_bug.cgi?id=215436
    Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1821
    Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1852
    Fixes: 2a50edbf10c8 ("drm/amd/display: Apply w/a for hard hang on HPD")
    Fixes: 1bd3bc745e7f ("drm/amd/display: Extend w/a for hard hang on HPD to dcn20")
    Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>

commit 73c260f09f0aa7ab79de33f191ae55248952e833
Author: Sanket Goswami <Sanket.Goswami@amd.com>
Date:   Tue Nov 30 16:53:18 2021 +0530

    platform/x86: amd-pmc: Add support for AMD Smart Trace Buffer (v6)

    STB (Smart Trace Buffer), is a debug trace buffer that isolates the
    failures by analyzing the last running feature of a system. This
    non-intrusive way always runs in the background and stores the trace
    into the SoC.

    This patch enables the STB feature by passing module param
    "enable_stb=1" while loading the driver and provides mechanism to
    access the STB buffer using the read and write routines.

    Co-developed-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
    Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
    Signed-off-by: Sanket Goswami <Sanket.Goswami@amd.com>

commit e6000d5a223f89882671e1aa61dd43e20051fe34
Author: Sanket Goswami <Sanket.Goswami@amd.com>
Date:   Tue Nov 30 16:53:17 2021 +0530

    platform/x86: amd-pmc: Simplify error handling and store the pci_dev in amd_pmc_dev structure

    Handle error-exits in the amd_pmc_probe() to avoid duplication and store
    the root port information in amd_pmc_probe() so that the information
    can be used across multiple routines.

    Suggested-by: Hans de Goede <hdegoede@redhat.com>
    Signed-off-by: Sanket Goswami <Sanket.Goswami@amd.com>

commit b6e9788d0f2d13aa2be66c88ca949ebf65ee32ea
Author: Julian Sikorski <belegdol+github@gmail.com>
Date:   Fri Nov 19 17:52:36 2021 +0100

    GFXOFF check patch by Lijo Lazar

commit af2cbc6459a8108dcc0b8a513630b794c38d8c19
Author: Mario Limonciello <mario.limonciello@amd.com>
Date:   Fri Sep 24 12:32:06 2021 -0500

    ACPI: PM: s2idle: Don't report missing devices as failing constraints

    ACPI tables may have entries for devices that are not physically
    present but that can be connected.  These devices shouldn't cause
    constraints checking to fail.

    Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
    Change-Id: I34f5ca978aab69ff0a0906191eec21649b19fe27
---
 drivers/acpi/x86/s2idle.c                     |   6 +
 .../display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c  |  11 +-
 .../amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c |  11 +-
 .../display/dc/irq/dcn20/irq_service_dcn20.c  |  25 ---
 .../display/dc/irq/dcn20/irq_service_dcn20.h  |   2 -
 .../display/dc/irq/dcn21/irq_service_dcn21.c  |  25 ---
 .../display/dc/irq/dcn21/irq_service_dcn21.h  |   2 -
 .../gpu/drm/amd/display/dc/irq/irq_service.c  |   2 +-
 .../gpu/drm/amd/display/dc/irq/irq_service.h  |   4 -
 drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c     |   5 +-
 drivers/platform/x86/amd-pmc.c                | 172 ++++++++++++++++--
 11 files changed, 170 insertions(+), 95 deletions(-)

diff --git a/drivers/acpi/x86/s2idle.c b/drivers/acpi/x86/s2idle.c
index 1c48358b43ba..0b65d4623214 100644
--- a/drivers/acpi/x86/s2idle.c
+++ b/drivers/acpi/x86/s2idle.c
@@ -309,6 +309,12 @@ static void lpi_check_constraints(void)
 			continue;
 		}
 
+		if (!acpi_get_first_physical_node(adev)) {
+			acpi_handle_debug(handle, "LPI: Device is not physically present\n");
+			lpi_constraints_table[i].handle = NULL;
+			continue;
+		}
+
 		if (adev->power.state < lpi_constraints_table[i].min_dstate)
 			acpi_handle_info(handle,
 				"LPI: Constraint not met; min power state:%s current power state:%s\n",
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c
index 2108bff49d4e..146e6d670899 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c
@@ -38,7 +38,6 @@
 #include "clk/clk_11_0_0_offset.h"
 #include "clk/clk_11_0_0_sh_mask.h"
 
-#include "irq/dcn20/irq_service_dcn20.h"
 
 #undef FN
 #define FN(reg_name, field_name) \
@@ -223,8 +222,6 @@ void dcn2_update_clocks(struct clk_mgr *clk_mgr_base,
 	bool force_reset = false;
 	bool p_state_change_support;
 	int total_plane_count;
-	int irq_src;
-	uint32_t hpd_state;
 
 	if (dc->work_arounds.skip_clock_update)
 		return;
@@ -242,13 +239,7 @@ void dcn2_update_clocks(struct clk_mgr *clk_mgr_base,
 	if (dc->res_pool->pp_smu)
 		pp_smu = &dc->res_pool->pp_smu->nv_funcs;
 
-	for (irq_src = DC_IRQ_SOURCE_HPD1; irq_src <= DC_IRQ_SOURCE_HPD6; irq_src++) {
-		hpd_state = dc_get_hpd_state_dcn20(dc->res_pool->irqs, irq_src);
-		if (hpd_state)
-			break;
-	}
-
-	if (display_count == 0 && !hpd_state)
+	if (display_count == 0)
 		enter_display_off = true;
 
 	if (enter_display_off == safe_to_lower) {
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c
index ac2d4c4f04e4..d3c8db65ff45 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn21/rn_clk_mgr.c
@@ -42,7 +42,6 @@
 #include "clk/clk_10_0_2_sh_mask.h"
 #include "renoir_ip_offset.h"
 
-#include "irq/dcn21/irq_service_dcn21.h"
 
 /* Constants */
 
@@ -130,11 +129,9 @@ void rn_update_clocks(struct clk_mgr *clk_mgr_base,
 	struct dc_clocks *new_clocks = &context->bw_ctx.bw.dcn.clk;
 	struct dc *dc = clk_mgr_base->ctx->dc;
 	int display_count;
-	int irq_src;
 	bool update_dppclk = false;
 	bool update_dispclk = false;
 	bool dpp_clock_lowered = false;
-	uint32_t hpd_state;
 
 	struct dmcu *dmcu = clk_mgr_base->ctx->dc->res_pool->dmcu;
 
@@ -151,14 +148,8 @@ void rn_update_clocks(struct clk_mgr *clk_mgr_base,
 
 			display_count = rn_get_active_display_cnt_wa(dc, context);
 
-			for (irq_src = DC_IRQ_SOURCE_HPD1; irq_src <= DC_IRQ_SOURCE_HPD5; irq_src++) {
-				hpd_state = dc_get_hpd_state_dcn21(dc->res_pool->irqs, irq_src);
-				if (hpd_state)
-					break;
-			}
-
 			/* if we can go lower, go lower */
-			if (display_count == 0 && !hpd_state) {
+			if (display_count == 0) {
 				rn_vbios_smu_set_dcn_low_power_state(clk_mgr, DCN_PWR_STATE_LOW_POWER);
 				/* update power state */
 				clk_mgr_base->clks.pwr_state = DCN_PWR_STATE_LOW_POWER;
diff --git a/drivers/gpu/drm/amd/display/dc/irq/dcn20/irq_service_dcn20.c b/drivers/gpu/drm/amd/display/dc/irq/dcn20/irq_service_dcn20.c
index 9ccafe007b23..c4b067d01895 100644
--- a/drivers/gpu/drm/amd/display/dc/irq/dcn20/irq_service_dcn20.c
+++ b/drivers/gpu/drm/amd/display/dc/irq/dcn20/irq_service_dcn20.c
@@ -132,31 +132,6 @@ enum dc_irq_source to_dal_irq_source_dcn20(
 	}
 }
 
-uint32_t dc_get_hpd_state_dcn20(struct irq_service *irq_service, enum dc_irq_source source)
-{
-	const struct irq_source_info *info;
-	uint32_t addr;
-	uint32_t value;
-	uint32_t current_status;
-
-	info = find_irq_source_info(irq_service, source);
-	if (!info)
-		return 0;
-
-	addr = info->status_reg;
-	if (!addr)
-		return 0;
-
-	value = dm_read_reg(irq_service->ctx, addr);
-	current_status =
-		get_reg_field_value(
-			value,
-			HPD0_DC_HPD_INT_STATUS,
-			DC_HPD_SENSE);
-
-	return current_status;
-}
-
 static bool hpd_ack(
 	struct irq_service *irq_service,
 	const struct irq_source_info *info)
diff --git a/drivers/gpu/drm/amd/display/dc/irq/dcn20/irq_service_dcn20.h b/drivers/gpu/drm/amd/display/dc/irq/dcn20/irq_service_dcn20.h
index 4d69ab24ca25..aee4b37999f1 100644
--- a/drivers/gpu/drm/amd/display/dc/irq/dcn20/irq_service_dcn20.h
+++ b/drivers/gpu/drm/amd/display/dc/irq/dcn20/irq_service_dcn20.h
@@ -31,6 +31,4 @@
 struct irq_service *dal_irq_service_dcn20_create(
 	struct irq_service_init_data *init_data);
 
-uint32_t dc_get_hpd_state_dcn20(struct irq_service *irq_service, enum dc_irq_source source);
-
 #endif
diff --git a/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.c b/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.c
index 78940cb20e10..ed54e1c819be 100644
--- a/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.c
+++ b/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.c
@@ -135,31 +135,6 @@ enum dc_irq_source to_dal_irq_source_dcn21(
 	return DC_IRQ_SOURCE_INVALID;
 }
 
-uint32_t dc_get_hpd_state_dcn21(struct irq_service *irq_service, enum dc_irq_source source)
-{
-	const struct irq_source_info *info;
-	uint32_t addr;
-	uint32_t value;
-	uint32_t current_status;
-
-	info = find_irq_source_info(irq_service, source);
-	if (!info)
-		return 0;
-
-	addr = info->status_reg;
-	if (!addr)
-		return 0;
-
-	value = dm_read_reg(irq_service->ctx, addr);
-	current_status =
-		get_reg_field_value(
-			value,
-			HPD0_DC_HPD_INT_STATUS,
-			DC_HPD_SENSE);
-
-	return current_status;
-}
-
 static bool hpd_ack(
 	struct irq_service *irq_service,
 	const struct irq_source_info *info)
diff --git a/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.h b/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.h
index 616470e32380..da2bd0e93d7a 100644
--- a/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.h
+++ b/drivers/gpu/drm/amd/display/dc/irq/dcn21/irq_service_dcn21.h
@@ -31,6 +31,4 @@
 struct irq_service *dal_irq_service_dcn21_create(
 	struct irq_service_init_data *init_data);
 
-uint32_t dc_get_hpd_state_dcn21(struct irq_service *irq_service, enum dc_irq_source source);
-
 #endif
diff --git a/drivers/gpu/drm/amd/display/dc/irq/irq_service.c b/drivers/gpu/drm/amd/display/dc/irq/irq_service.c
index 4db1133e4466..a2a4fbeb83f8 100644
--- a/drivers/gpu/drm/amd/display/dc/irq/irq_service.c
+++ b/drivers/gpu/drm/amd/display/dc/irq/irq_service.c
@@ -79,7 +79,7 @@ void dal_irq_service_destroy(struct irq_service **irq_service)
 	*irq_service = NULL;
 }
 
-const struct irq_source_info *find_irq_source_info(
+static const struct irq_source_info *find_irq_source_info(
 	struct irq_service *irq_service,
 	enum dc_irq_source source)
 {
diff --git a/drivers/gpu/drm/amd/display/dc/irq/irq_service.h b/drivers/gpu/drm/amd/display/dc/irq/irq_service.h
index e60b82480093..dbfcb096eedd 100644
--- a/drivers/gpu/drm/amd/display/dc/irq/irq_service.h
+++ b/drivers/gpu/drm/amd/display/dc/irq/irq_service.h
@@ -69,10 +69,6 @@ struct irq_service {
 	const struct irq_service_funcs *funcs;
 };
 
-const struct irq_source_info *find_irq_source_info(
-	struct irq_service *irq_service,
-	enum dc_irq_source source);
-
 void dal_irq_service_construct(
 	struct irq_service *irq_service,
 	struct irq_service_init_data *init_data);
diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
index 9d7d64fdf410..37e83df92264 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c
@@ -277,8 +277,11 @@ static int smu_dpm_set_power_gate(void *handle,
 	struct smu_context *smu = handle;
 	int ret = 0;
 
-	if (!smu->pm_enabled || !smu->adev->pm.dpm_enabled)
+	if (!smu->pm_enabled || !smu->adev->pm.dpm_enabled) {
+		WARN(true, "SMU uninitialized but power %s requested for %u!\n",
+		     gate ? "gate" : "ungate", block_type);
 		return -EOPNOTSUPP;
+	}
 
 	switch (block_type) {
 	/*
diff --git a/drivers/platform/x86/amd-pmc.c b/drivers/platform/x86/amd-pmc.c
index 230593ae5d6d..15a5b23e7b8d 100644
--- a/drivers/platform/x86/amd-pmc.c
+++ b/drivers/platform/x86/amd-pmc.c
@@ -35,6 +35,12 @@
 #define AMD_PMC_SCRATCH_REG_CZN		0x94
 #define AMD_PMC_SCRATCH_REG_YC		0xD14
 
+/* STB Registers */
+#define AMD_PMC_STB_INDEX_ADDRESS	0xF8
+#define AMD_PMC_STB_INDEX_DATA		0xFC
+#define AMD_PMC_STB_PMI_0		0x03E30600
+#define AMD_PMC_STB_PREDEF		0xC6000001
+
 /* Base address of SMU for mapping physical address to virtual address */
 #define AMD_PMC_SMU_INDEX_ADDRESS	0xB8
 #define AMD_PMC_SMU_INDEX_DATA		0xBC
@@ -82,6 +88,7 @@
 #define SOC_SUBSYSTEM_IP_MAX	12
 #define DELAY_MIN_US		2000
 #define DELAY_MAX_US		3000
+#define FIFO_SIZE		4096
 enum amd_pmc_def {
 	MSG_TEST = 0x01,
 	MSG_OS_HINT_PCO,
@@ -121,14 +128,21 @@ struct amd_pmc_dev {
 	u16 minor;
 	u16 rev;
 	struct device *dev;
+	struct pci_dev *rdev;
 	struct mutex lock; /* generic mutex lock */
 #if IS_ENABLED(CONFIG_DEBUG_FS)
 	struct dentry *dbgfs_dir;
 #endif /* CONFIG_DEBUG_FS */
 };
 
+static bool enable_stb;
+module_param(enable_stb, bool, 0644);
+MODULE_PARM_DESC(enable_stb, "Enable the STB debug mechanism");
+
 static struct amd_pmc_dev pmc;
 static int amd_pmc_send_cmd(struct amd_pmc_dev *dev, u32 arg, u32 *data, u8 msg, bool ret);
+static int amd_pmc_write_stb(struct amd_pmc_dev *dev, u32 data);
+static int amd_pmc_read_stb(struct amd_pmc_dev *dev, u32 *buf);
 
 static inline u32 amd_pmc_reg_read(struct amd_pmc_dev *dev, int reg_offset)
 {
@@ -175,6 +189,50 @@ static int amd_pmc_get_smu_version(struct amd_pmc_dev *dev)
 	return 0;
 }
 
+static int amd_pmc_stb_debugfs_open(struct inode *inode, struct file *filp)
+{
+	struct amd_pmc_dev *dev = filp->f_inode->i_private;
+	u32 size = FIFO_SIZE * sizeof(u32);
+	u32 *buf;
+	int rc;
+
+	buf = kzalloc(size, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	rc = amd_pmc_read_stb(dev, buf);
+	if (rc) {
+		kfree(buf);
+		return rc;
+	}
+
+	filp->private_data = buf;
+	return rc;
+}
+
+static ssize_t amd_pmc_stb_debugfs_read(struct file *filp, char __user *buf, size_t size,
+					loff_t *pos)
+{
+	if (!filp->private_data)
+		return -EINVAL;
+
+	return simple_read_from_buffer(buf, size, pos, filp->private_data,
+				       FIFO_SIZE * sizeof(u32));
+}
+
+static int amd_pmc_stb_debugfs_release(struct inode *inode, struct file *filp)
+{
+	kfree(filp->private_data);
+	return 0;
+}
+
+const struct file_operations amd_pmc_stb_debugfs_fops = {
+	.owner = THIS_MODULE,
+	.open = amd_pmc_stb_debugfs_open,
+	.read = amd_pmc_stb_debugfs_read,
+	.release = amd_pmc_stb_debugfs_release,
+};
+
 static int amd_pmc_idlemask_read(struct amd_pmc_dev *pdev, struct device *dev,
 				 struct seq_file *s)
 {
@@ -288,6 +346,10 @@ static void amd_pmc_dbgfs_register(struct amd_pmc_dev *dev)
 			    &s0ix_stats_fops);
 	debugfs_create_file("amd_pmc_idlemask", 0644, dev->dbgfs_dir, dev,
 			    &amd_pmc_idlemask_fops);
+	/* Enable STB only when the module_param is set */
+	if (enable_stb)
+		debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
+				    &amd_pmc_stb_debugfs_fops);
 }
 #else
 static inline void amd_pmc_dbgfs_register(struct amd_pmc_dev *dev)
@@ -484,6 +546,13 @@ static int __maybe_unused amd_pmc_suspend(struct device *dev)
 	if (rc)
 		dev_err(pdev->dev, "suspend failed\n");
 
+	if (enable_stb)
+		rc = amd_pmc_write_stb(pdev, AMD_PMC_STB_PREDEF);
+	if (rc)	{
+		dev_err(pdev->dev, "error writing to STB\n");
+		return rc;
+	}
+
 	return rc;
 }
 
@@ -504,6 +573,14 @@ static int __maybe_unused amd_pmc_resume(struct device *dev)
 	/* Dump the IdleMask to see the blockers */
 	amd_pmc_idlemask_read(pdev, dev, NULL);
 
+	/* Write data incremented by 1 to distinguish in stb_read */
+	if (enable_stb)
+		rc = amd_pmc_write_stb(pdev, AMD_PMC_STB_PREDEF + 1);
+	if (rc)	{
+		dev_err(pdev->dev, "error writing to STB\n");
+		return rc;
+	}
+
 	return 0;
 }
 
@@ -521,6 +598,62 @@ static const struct pci_device_id pmc_pci_ids[] = {
 	{ }
 };
 
+static int amd_pmc_write_stb(struct amd_pmc_dev *dev, u32 data)
+{
+	int err;
+
+	err = pci_write_config_dword(dev->rdev, AMD_PMC_STB_INDEX_ADDRESS, AMD_PMC_STB_PMI_0);
+	if (err) {
+		dev_err(dev->dev, "failed to write addr in stb: 0x%X\n",
+			AMD_PMC_STB_INDEX_ADDRESS);
+		err = pcibios_err_to_errno(err);
+		goto err_pci_dev_put;
+	}
+
+	err = pci_write_config_dword(dev->rdev, AMD_PMC_STB_INDEX_DATA, data);
+	if (err) {
+		dev_err(dev->dev, "failed to write data in stb: 0x%X\n",
+			AMD_PMC_STB_INDEX_DATA);
+		err = pcibios_err_to_errno(err);
+		goto err_pci_dev_put;
+	}
+
+	return 0;
+
+err_pci_dev_put:
+	pci_dev_put(dev->rdev);
+	return err;
+}
+
+static int amd_pmc_read_stb(struct amd_pmc_dev *dev, u32 *buf)
+{
+	int i, err;
+
+	err = pci_write_config_dword(dev->rdev, AMD_PMC_STB_INDEX_ADDRESS, AMD_PMC_STB_PMI_0);
+	if (err) {
+		dev_err(dev->dev, "error writing addr to stb: 0x%X\n",
+			AMD_PMC_STB_INDEX_ADDRESS);
+		err = pcibios_err_to_errno(err);
+		goto err_pci_dev_put;
+	}
+
+	for (i = 0; i < FIFO_SIZE; i++) {
+		err = pci_read_config_dword(dev->rdev, AMD_PMC_STB_INDEX_DATA, buf++);
+		if (err) {
+			dev_err(dev->dev, "error reading data from stb: 0x%X\n",
+				AMD_PMC_STB_INDEX_DATA);
+			err = pcibios_err_to_errno(err);
+			goto err_pci_dev_put;
+		}
+	}
+
+	return 0;
+
+err_pci_dev_put:
+	pci_dev_put(dev->rdev);
+	return err;
+}
+
 static int amd_pmc_probe(struct platform_device *pdev)
 {
 	struct amd_pmc_dev *dev = &pmc;
@@ -534,22 +667,23 @@ static int amd_pmc_probe(struct platform_device *pdev)
 
 	rdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0));
 	if (!rdev || !pci_match_id(pmc_pci_ids, rdev)) {
-		pci_dev_put(rdev);
-		return -ENODEV;
+		err = -ENODEV;
+		goto err_pci_dev_put;
 	}
 
 	dev->cpu_id = rdev->device;
+	dev->rdev = rdev;
 	err = pci_write_config_dword(rdev, AMD_PMC_SMU_INDEX_ADDRESS, AMD_PMC_BASE_ADDR_LO);
 	if (err) {
 		dev_err(dev->dev, "error writing to 0x%x\n", AMD_PMC_SMU_INDEX_ADDRESS);
-		pci_dev_put(rdev);
-		return pcibios_err_to_errno(err);
+		err = pcibios_err_to_errno(err);
+		goto err_pci_dev_put;
 	}
 
 	err = pci_read_config_dword(rdev, AMD_PMC_SMU_INDEX_DATA, &val);
 	if (err) {
-		pci_dev_put(rdev);
-		return pcibios_err_to_errno(err);
+		err = pcibios_err_to_errno(err);
+		goto err_pci_dev_put;
 	}
 
 	base_addr_lo = val & AMD_PMC_BASE_ADDR_HI_MASK;
@@ -557,24 +691,25 @@ static int amd_pmc_probe(struct platform_device *pdev)
 	err = pci_write_config_dword(rdev, AMD_PMC_SMU_INDEX_ADDRESS, AMD_PMC_BASE_ADDR_HI);
 	if (err) {
 		dev_err(dev->dev, "error writing to 0x%x\n", AMD_PMC_SMU_INDEX_ADDRESS);
-		pci_dev_put(rdev);
-		return pcibios_err_to_errno(err);
+		err = pcibios_err_to_errno(err);
+		goto err_pci_dev_put;
 	}
 
 	err = pci_read_config_dword(rdev, AMD_PMC_SMU_INDEX_DATA, &val);
 	if (err) {
-		pci_dev_put(rdev);
-		return pcibios_err_to_errno(err);
+		err = pcibios_err_to_errno(err);
+		goto err_pci_dev_put;
 	}
 
 	base_addr_hi = val & AMD_PMC_BASE_ADDR_LO_MASK;
-	pci_dev_put(rdev);
 	base_addr = ((u64)base_addr_hi << 32 | base_addr_lo);
 
 	dev->regbase = devm_ioremap(dev->dev, base_addr + AMD_PMC_BASE_ADDR_OFFSET,
 				    AMD_PMC_MAPPING_SIZE);
-	if (!dev->regbase)
-		return -ENOMEM;
+	if (!dev->regbase) {
+		err = -ENOMEM;
+		goto err_pci_dev_put;
+	}
 
 	mutex_init(&dev->lock);
 
@@ -583,8 +718,10 @@ static int amd_pmc_probe(struct platform_device *pdev)
 	base_addr_hi = FCH_BASE_PHY_ADDR_HIGH;
 	fch_phys_addr = ((u64)base_addr_hi << 32 | base_addr_lo);
 	dev->fch_virt_addr = devm_ioremap(dev->dev, fch_phys_addr, FCH_SSC_MAPPING_SIZE);
-	if (!dev->fch_virt_addr)
-		return -ENOMEM;
+	if (!dev->fch_virt_addr) {
+		err = -ENOMEM;
+		goto err_pci_dev_put;
+	}
 
 	/* Use SMU to get the s0i3 debug stats */
 	err = amd_pmc_setup_smu_logging(dev);
@@ -595,6 +732,10 @@ static int amd_pmc_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, dev);
 	amd_pmc_dbgfs_register(dev);
 	return 0;
+
+err_pci_dev_put:
+	pci_dev_put(rdev);
+	return err;
 }
 
 static int amd_pmc_remove(struct platform_device *pdev)
@@ -602,6 +743,7 @@ static int amd_pmc_remove(struct platform_device *pdev)
 	struct amd_pmc_dev *dev = platform_get_drvdata(pdev);
 
 	amd_pmc_dbgfs_unregister(dev);
+	pci_dev_put(dev->rdev);
 	mutex_destroy(&dev->lock);
 	return 0;
 }
-- 
2.34.1