FAILED: patch "[PATCH] platform/x86/amd/pmc: Propagate SMU errors and validate S2D" failed to apply to 6.1-stable tree

FAILED: patch "[PATCH] platform/x86/amd/pmc: Propagate SMU errors and validate S2D" failed to apply to 6.1-stable tree

[gregkh]

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 0225c1d637687b03726f00ac65b6def843d2c464
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026090317-buggy-snowboard-d47e@gregkh' --subject-prefix 'PATCH 6.1.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 0225c1d637687b03726f00ac65b6def843d2c464 Mon Sep 17 00:00:00 2001
From: Mario Limonciello <mario.limonciello@amd.com>
Date: Tue, 21 Jul 2026 13:17:53 -0500
Subject: [PATCH] platform/x86/amd/pmc: Propagate SMU errors and validate S2D
 address
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

amd_stb_s2d_init() discards the return value of several S2D SMU commands.
When the SMU refuses a command (e.g. "SMU cmd failed. err: 0xff") the
failure is only noticed indirectly - if at all - and reported as -EIO,
masking the real error.

More seriously, the S2D_PHYS_ADDR_LOW/HIGH return values are ignored, so
on failure phys_addr_low/hi are left uninitialised and the assembled
address is passed straight to devm_ioremap().  When the SMU leaves them at
zero this maps physical address 0 and trips the ioremap-on-RAM warning:

  amd_pmc AMDI000B:00: SMU cmd failed. err: 0xff
  ioremap on RAM at 0x0000000000000000 - 0x0000000000ffffff
  WARNING: CPU: 13 PID: 4592 at arch/x86/mm/ioremap.c:...

Check the return value of each SMU command and propagate it, and reject a
zero physical address before calling devm_ioremap().

Reported-by: Francis De Brabandere <francisdb@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221759
Tested-by: Francis De Brabandere <francisdb@gmail.com>
Fixes: 3d7d407dfb05 ("platform/x86: amd-pmc: Add support for AMD Spill to DRAM STB feature")
Cc: stable@vger.kernel.org
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://patch.msgid.link/20260721181756.143084-4-mario.limonciello@amd.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

diff --git a/drivers/platform/x86/amd/pmc/mp1_stb.c b/drivers/platform/x86/amd/pmc/mp1_stb.c
index 90b8a5cebfa8..1ec0e599df7f 100644
--- a/drivers/platform/x86/amd/pmc/mp1_stb.c
+++ b/drivers/platform/x86/amd/pmc/mp1_stb.c
@@ -311,30 +311,39 @@ int amd_stb_s2d_init(struct amd_pmc_dev *dev)
 	/* Spill to DRAM feature uses separate SMU message port */
 	dev->msg_port = MSG_PORT_S2D;
 
-	amd_pmc_send_cmd(dev, S2D_TELEMETRY_SIZE, &size, dev->stb_arg.s2d_msg_id, true);
+	ret = amd_pmc_send_cmd(dev, S2D_TELEMETRY_SIZE, &size, dev->stb_arg.s2d_msg_id, true);
+	if (ret)
+		goto out;
 	if (size != S2D_TELEMETRY_BYTES_MAX) {
 		ret = -EIO;
 		goto out;
 	}
 
-	/* Get DRAM size */
-	ret = amd_pmc_send_cmd(dev, S2D_DRAM_SIZE, &dev->dram_size, dev->stb_arg.s2d_msg_id, true);
-	if (ret || !dev->dram_size)
+	/* Get DRAM size; fall back to the default if the query fails */
+	if (amd_pmc_send_cmd(dev, S2D_DRAM_SIZE, &dev->dram_size, dev->stb_arg.s2d_msg_id, true) ||
+	    !dev->dram_size)
 		dev->dram_size = S2D_TELEMETRY_DRAMBYTES_MAX;
 
 	/* Get STB DRAM address */
-	amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_LOW, &phys_addr_low, dev->stb_arg.s2d_msg_id, true);
-	amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_HIGH, &phys_addr_hi, dev->stb_arg.s2d_msg_id, true);
+	ret = amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_LOW, &phys_addr_low,
+			       dev->stb_arg.s2d_msg_id, true);
+	if (ret)
+		goto out;
+	ret = amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_HIGH, &phys_addr_hi,
+			       dev->stb_arg.s2d_msg_id, true);
+	if (ret)
+		goto out;
 
 	stb_phys_addr = ((u64)phys_addr_hi << 32 | phys_addr_low);
-
-	dev->stb_virt_addr = devm_ioremap(dev->dev, stb_phys_addr, dev->dram_size);
-	if (!dev->stb_virt_addr) {
-		ret = -ENOMEM;
+	if (!stb_phys_addr) {
+		dev_err(dev->dev, "S2D phys addr query returned invalid address\n");
+		ret = -ENXIO;
 		goto out;
 	}
 
-	ret = 0;
+	dev->stb_virt_addr = devm_ioremap(dev->dev, stb_phys_addr, dev->dram_size);
+	if (!dev->stb_virt_addr)
+		ret = -ENOMEM;
 
 out:
 	/* Restore the default message port for subsequent SMU operations */

[PATCH 6.1.y 1/3] platform/x86/amd/pmc: Move STB functionality to a new file for better code organization

[Sasha Levin]

From: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>

[ Upstream commit 0e914063ddd135407c0550b77a6f5bf779bf8384 ]

As the SoC evolves with each generation, the dynamics between the PMC and
STB layers within the PMC driver are becoming increasingly complex, making
it challenging to manage both in a single file and maintain code
readability.

Additionally, during silicon bringup, the PMC functionality is often
enabled first, with STB functionality added later. This can lead to missed
updates in the driver, potentially causing issues.

To address these challenges, it's beneficial to move all STB-related
changes to a separate file. This approach will better accommodate newer
SoCs, provide improved flexibility for desktop variants, and facilitate
the collection of additional debug information through STB mechanisms.

Also the additional checks for entering s2d_init have been moved from
the PMC probe to amd_pmc_s2d_init(). This adjustment makes more sense
following the transfer of code to the separate mp1_stb.c file.

Co-developed-by: Sanket Goswami <Sanket.Goswami@amd.com>
Signed-off-by: Sanket Goswami <Sanket.Goswami@amd.com>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Link: https://lore.kernel.org/r/20241108070822.3912689-3-Shyam-sundar.S-k@amd.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

[Backport dependency for 0225c1d637687 to Linux 6.1]
Move the existing PMC source into pmc/ and extract only the STB functions
already present in this stable tree. Add the composite-module Makefile and
a shared header containing the stable device structure and the declarations
needed by the split. No functions or new platform support are introduced.
Keep enable_stb, CPU gating and debugfs registration in their original PMC
paths; omit MP2, enhanced STB dumping and newer firmware/platform helpers.

Prepare the existing S2D initializer for the target's three-way cherry-pick:
provide stb_arg.s2d_msg_id using the existing 0xBE command, query DRAM size
with the existing 16 MiB default, and restore the PMC message port through
a common exit. Preserve the stable zero-address rejection before mapping.
The target then supplies SMU command error propagation without requiring
the intervening upstream feature additions or helper functions.

Stable-dep-of: 0225c1d63768 ("platform/x86/amd/pmc: Propagate SMU errors and validate S2D address")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/platform/x86/amd/Makefile        |   3 +-
 drivers/platform/x86/amd/pmc/Makefile    |   4 +
 drivers/platform/x86/amd/pmc/mp1_stb.c   | 201 +++++++++++++++++++++++
 drivers/platform/x86/amd/{ => pmc}/pmc.c | 188 +--------------------
 drivers/platform/x86/amd/pmc/pmc.h       |  48 ++++++
 5 files changed, 257 insertions(+), 187 deletions(-)
 create mode 100644 drivers/platform/x86/amd/pmc/Makefile
 create mode 100644 drivers/platform/x86/amd/pmc/mp1_stb.c
 rename drivers/platform/x86/amd/{ => pmc}/pmc.c (82%)
 create mode 100644 drivers/platform/x86/amd/pmc/pmc.h

diff --git a/drivers/platform/x86/amd/Makefile b/drivers/platform/x86/amd/Makefile
index 2c229198e24c9..f04932b7a7d12 100644
--- a/drivers/platform/x86/amd/Makefile
+++ b/drivers/platform/x86/amd/Makefile
@@ -4,8 +4,7 @@
 # AMD x86 Platform-Specific Drivers
 #
 
-amd-pmc-y			:= pmc.o
-obj-$(CONFIG_AMD_PMC)		+= amd-pmc.o
+obj-$(CONFIG_AMD_PMC)		+= pmc/
 amd_hsmp-y			:= hsmp.o
 obj-$(CONFIG_AMD_HSMP)		+= amd_hsmp.o
 obj-$(CONFIG_AMD_PMF)		+= pmf/
diff --git a/drivers/platform/x86/amd/pmc/Makefile b/drivers/platform/x86/amd/pmc/Makefile
new file mode 100644
index 0000000000000..3c50d54f6aa2e
--- /dev/null
+++ b/drivers/platform/x86/amd/pmc/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_AMD_PMC) += amd-pmc.o
+amd-pmc-y := pmc.o mp1_stb.o
diff --git a/drivers/platform/x86/amd/pmc/mp1_stb.c b/drivers/platform/x86/amd/pmc/mp1_stb.c
new file mode 100644
index 0000000000000..52fc05a1bad68
--- /dev/null
+++ b/drivers/platform/x86/amd/pmc/mp1_stb.c
@@ -0,0 +1,201 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * AMD MP1 Smart Trace Buffer (STB) Layer
+ *
+ * Copyright (c) 2024, Advanced Micro Devices, Inc.
+ * All Rights Reserved.
+ *
+ * Authors: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
+ *          Sanket Goswami <Sanket.Goswami@amd.com>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <asm/amd_nb.h>
+#include <linux/debugfs.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+
+#include "pmc.h"
+
+/* STB Spill to DRAM Parameters */
+#define S2D_TELEMETRY_BYTES_MAX		0x100000
+#define S2D_TELEMETRY_DRAMBYTES_MAX	0x1000000
+
+/* STB Registers */
+#define AMD_PMC_STB_PMI_0		0x03E30600
+#define FIFO_SIZE		4096
+
+/* STB Spill to DRAM Message Definition */
+#define STB_SPILL_TO_DRAM		0xBE
+
+enum s2d_arg {
+	S2D_TELEMETRY_SIZE = 0x01,
+	S2D_PHYS_ADDR_LOW,
+	S2D_PHYS_ADDR_HIGH,
+	S2D_NUM_SAMPLES,
+	S2D_DRAM_SIZE,
+};
+
+#ifdef CONFIG_SUSPEND
+int amd_pmc_write_stb(struct amd_pmc_dev *dev, u32 data)
+{
+	int err;
+
+	err = amd_smn_write(0, AMD_PMC_STB_PMI_0, data);
+	if (err) {
+		dev_err(dev->dev, "failed to write data in stb: 0x%X\n", AMD_PMC_STB_PMI_0);
+		return pcibios_err_to_errno(err);
+	}
+
+	return 0;
+}
+#endif
+
+static int amd_pmc_read_stb(struct amd_pmc_dev *dev, u32 *buf)
+{
+	int i, err;
+
+	for (i = 0; i < FIFO_SIZE; i++) {
+		err = amd_smn_read(0, AMD_PMC_STB_PMI_0, buf++);
+		if (err) {
+			dev_err(dev->dev, "error reading data from stb: 0x%X\n", AMD_PMC_STB_PMI_0);
+			return pcibios_err_to_errno(err);
+		}
+	}
+
+	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_stb_debugfs_open_v2(struct inode *inode, struct file *filp)
+{
+	struct amd_pmc_dev *dev = filp->f_inode->i_private;
+	u32 *buf;
+
+	buf = kzalloc(S2D_TELEMETRY_BYTES_MAX, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	memcpy_fromio(buf, dev->stb_virt_addr, S2D_TELEMETRY_BYTES_MAX);
+	filp->private_data = buf;
+
+	return 0;
+}
+
+static ssize_t amd_pmc_stb_debugfs_read_v2(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,
+					S2D_TELEMETRY_BYTES_MAX);
+}
+
+static int amd_pmc_stb_debugfs_release_v2(struct inode *inode, struct file *filp)
+{
+	kfree(filp->private_data);
+	return 0;
+}
+
+const struct file_operations amd_pmc_stb_debugfs_fops_v2 = {
+	.owner = THIS_MODULE,
+	.open = amd_pmc_stb_debugfs_open_v2,
+	.read = amd_pmc_stb_debugfs_read_v2,
+	.release = amd_pmc_stb_debugfs_release_v2,
+};
+
+int amd_pmc_s2d_init(struct amd_pmc_dev *dev)
+{
+	u32 phys_addr_low, phys_addr_hi;
+	u64 stb_phys_addr;
+	u32 size = 0;
+	int ret = 0;
+
+	dev->stb_arg.s2d_msg_id = STB_SPILL_TO_DRAM;
+
+	/* Spill to DRAM feature uses separate SMU message port */
+	dev->msg_port = MSG_PORT_S2D;
+
+	amd_pmc_send_cmd(dev, S2D_TELEMETRY_SIZE, &size, dev->stb_arg.s2d_msg_id, true);
+	if (size != S2D_TELEMETRY_BYTES_MAX) {
+		ret = -EIO;
+		goto out;
+	}
+
+	/* Get DRAM size */
+	ret = amd_pmc_send_cmd(dev, S2D_DRAM_SIZE, &dev->dram_size, dev->stb_arg.s2d_msg_id, true);
+	if (ret || !dev->dram_size)
+		dev->dram_size = S2D_TELEMETRY_DRAMBYTES_MAX;
+
+	/* Get STB DRAM address */
+	amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_LOW, &phys_addr_low, dev->stb_arg.s2d_msg_id, true);
+	amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_HIGH, &phys_addr_hi, dev->stb_arg.s2d_msg_id, true);
+
+	if (!phys_addr_hi && !phys_addr_low) {
+		dev_err(dev->dev, "STB is not enabled on the system; disable enable_stb or contact system vendor\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	stb_phys_addr = ((u64)phys_addr_hi << 32 | phys_addr_low);
+
+	dev->stb_virt_addr = devm_ioremap(dev->dev, stb_phys_addr, dev->dram_size);
+	if (!dev->stb_virt_addr) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ret = 0;
+
+out:
+	/* Restore the default message port for subsequent SMU operations */
+	dev->msg_port = MSG_PORT_PMC;
+	return ret;
+}
diff --git a/drivers/platform/x86/amd/pmc.c b/drivers/platform/x86/amd/pmc/pmc.c
similarity index 82%
rename from drivers/platform/x86/amd/pmc.c
rename to drivers/platform/x86/amd/pmc/pmc.c
index 8eaeb1e8f9753..4740476df007b 100644
--- a/drivers/platform/x86/amd/pmc.c
+++ b/drivers/platform/x86/amd/pmc/pmc.c
@@ -28,6 +28,8 @@
 #include <linux/seq_file.h>
 #include <linux/uaccess.h>
 
+#include "pmc.h"
+
 /* SMU communication registers */
 #define AMD_PMC_REGISTER_MESSAGE	0x538
 #define AMD_PMC_REGISTER_RESPONSE	0x980
@@ -38,21 +40,15 @@
 #define AMD_PMC_SCRATCH_REG_YC		0xD14
 
 /* STB Registers */
-#define AMD_PMC_STB_PMI_0		0x03E30600
 #define AMD_PMC_STB_S2IDLE_PREPARE	0xC6000001
 #define AMD_PMC_STB_S2IDLE_RESTORE	0xC6000002
 #define AMD_PMC_STB_S2IDLE_CHECK	0xC6000003
 
 /* STB S2D(Spill to DRAM) has different message port offset */
-#define STB_SPILL_TO_DRAM		0xBE
 #define AMD_S2D_REGISTER_MESSAGE	0xA20
 #define AMD_S2D_REGISTER_RESPONSE	0xA80
 #define AMD_S2D_REGISTER_ARGUMENT	0xA88
 
-/* STB Spill to DRAM Parameters */
-#define S2D_TELEMETRY_BYTES_MAX		0x100000
-#define S2D_TELEMETRY_DRAMBYTES_MAX	0x1000000
-
 /* Base address of SMU for mapping physical address to virtual address */
 #define AMD_PMC_MAPPING_SIZE		0x01000
 #define AMD_PMC_BASE_ADDR_OFFSET	0x10000
@@ -100,19 +96,12 @@
 #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,
 	MSG_OS_HINT_RN,
 };
 
-enum s2d_arg {
-	S2D_TELEMETRY_SIZE = 0x01,
-	S2D_PHYS_ADDR_LOW,
-	S2D_PHYS_ADDR_HIGH,
-};
-
 struct amd_pmc_bit_map {
 	const char *name;
 	u32 bit_mask;
@@ -134,36 +123,11 @@ static const struct amd_pmc_bit_map soc15_ip_blk[] = {
 	{}
 };
 
-struct amd_pmc_dev {
-	void __iomem *regbase;
-	void __iomem *smu_virt_addr;
-	void __iomem *stb_virt_addr;
-	void __iomem *fch_virt_addr;
-	bool msg_port;
-	u32 base_addr;
-	u32 cpu_id;
-	u32 active_ips;
-/* SMU version information */
-	u8 smu_program;
-	u8 major;
-	u8 minor;
-	u8 rev;
-	struct device *dev;
-	struct pci_dev *rdev;
-	struct mutex lock; /* generic mutex lock */
-	struct dentry *dbgfs_dir;
-};
-
 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_read_stb(struct amd_pmc_dev *dev, u32 *buf);
-#ifdef CONFIG_SUSPEND
-static int amd_pmc_write_stb(struct amd_pmc_dev *dev, u32 data);
-#endif
 
 static inline u32 amd_pmc_reg_read(struct amd_pmc_dev *dev, int reg_offset)
 {
@@ -192,88 +156,6 @@ struct smu_metrics {
 	u64 timecondition_notmet_totaltime[SOC_SUBSYSTEM_IP_MAX];
 } __packed;
 
-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;
-}
-
-static 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_stb_debugfs_open_v2(struct inode *inode, struct file *filp)
-{
-	struct amd_pmc_dev *dev = filp->f_inode->i_private;
-	u32 *buf;
-
-	buf = kzalloc(S2D_TELEMETRY_BYTES_MAX, GFP_KERNEL);
-	if (!buf)
-		return -ENOMEM;
-
-	memcpy_fromio(buf, dev->stb_virt_addr, S2D_TELEMETRY_BYTES_MAX);
-	filp->private_data = buf;
-
-	return 0;
-}
-
-static ssize_t amd_pmc_stb_debugfs_read_v2(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,
-					S2D_TELEMETRY_BYTES_MAX);
-}
-
-static int amd_pmc_stb_debugfs_release_v2(struct inode *inode, struct file *filp)
-{
-	kfree(filp->private_data);
-	return 0;
-}
-
-static const struct file_operations amd_pmc_stb_debugfs_fops_v2 = {
-	.owner = THIS_MODULE,
-	.open = amd_pmc_stb_debugfs_open_v2,
-	.read = amd_pmc_stb_debugfs_read_v2,
-	.release = amd_pmc_stb_debugfs_release_v2,
-};
-
 static int amd_pmc_setup_smu_logging(struct amd_pmc_dev *dev)
 {
 	if (dev->cpu_id == AMD_CPU_ID_PCO) {
@@ -576,7 +458,7 @@ static void amd_pmc_dump_registers(struct amd_pmc_dev *dev)
 	dev_dbg(dev->dev, "AMD_PMC_REGISTER_MESSAGE:%x\n", value);
 }
 
-static int amd_pmc_send_cmd(struct amd_pmc_dev *dev, u32 arg, u32 *data, u8 msg, bool ret)
+int amd_pmc_send_cmd(struct amd_pmc_dev *dev, u32 arg, u32 *data, u8 msg, bool ret)
 {
 	int rc;
 	u32 val, message, argument, response;
@@ -867,70 +749,6 @@ static const struct pci_device_id pmc_pci_ids[] = {
 	{ }
 };
 
-static int amd_pmc_s2d_init(struct amd_pmc_dev *dev)
-{
-	u32 phys_addr_low, phys_addr_hi;
-	u64 stb_phys_addr;
-	u32 size = 0;
-
-	/* Spill to DRAM feature uses separate SMU message port */
-	dev->msg_port = 1;
-
-	amd_pmc_send_cmd(dev, S2D_TELEMETRY_SIZE, &size, STB_SPILL_TO_DRAM, 1);
-	if (size != S2D_TELEMETRY_BYTES_MAX)
-		return -EIO;
-
-	/* Get STB DRAM address */
-	amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_LOW, &phys_addr_low, STB_SPILL_TO_DRAM, 1);
-	amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_HIGH, &phys_addr_hi, STB_SPILL_TO_DRAM, 1);
-
-	if (!phys_addr_hi && !phys_addr_low) {
-		dev_err(dev->dev, "STB is not enabled on the system; disable enable_stb or contact system vendor\n");
-		return -EINVAL;
-	}
-
-	stb_phys_addr = ((u64)phys_addr_hi << 32 | phys_addr_low);
-
-	/* Clear msg_port for other SMU operation */
-	dev->msg_port = 0;
-
-	dev->stb_virt_addr = devm_ioremap(dev->dev, stb_phys_addr, S2D_TELEMETRY_DRAMBYTES_MAX);
-	if (!dev->stb_virt_addr)
-		return -ENOMEM;
-
-	return 0;
-}
-
-#ifdef CONFIG_SUSPEND
-static int amd_pmc_write_stb(struct amd_pmc_dev *dev, u32 data)
-{
-	int err;
-
-	err = amd_smn_write(0, AMD_PMC_STB_PMI_0, data);
-	if (err) {
-		dev_err(dev->dev, "failed to write data in stb: 0x%X\n", AMD_PMC_STB_PMI_0);
-		return pcibios_err_to_errno(err);
-	}
-
-	return 0;
-}
-#endif
-
-static int amd_pmc_read_stb(struct amd_pmc_dev *dev, u32 *buf)
-{
-	int i, err;
-
-	for (i = 0; i < FIFO_SIZE; i++) {
-		err = amd_smn_read(0, AMD_PMC_STB_PMI_0, buf++);
-		if (err) {
-			dev_err(dev->dev, "error reading data from stb: 0x%X\n", AMD_PMC_STB_PMI_0);
-			return pcibios_err_to_errno(err);
-		}
-	}
-
-	return 0;
-}
-
 static int amd_pmc_probe(struct platform_device *pdev)
 {
 	struct amd_pmc_dev *dev = &pmc;
diff --git a/drivers/platform/x86/amd/pmc/pmc.h b/drivers/platform/x86/amd/pmc/pmc.h
new file mode 100644
index 0000000000000..f372321eb37a0
--- /dev/null
+++ b/drivers/platform/x86/amd/pmc/pmc.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef PMC_H
+#define PMC_H
+
+#include <linux/mutex.h>
+#include <linux/types.h>
+
+enum s2d_msg_port {
+	MSG_PORT_PMC,
+	MSG_PORT_S2D,
+};
+
+struct stb_arg {
+	u32 s2d_msg_id;
+};
+
+struct amd_pmc_dev {
+	void __iomem *regbase;
+	void __iomem *smu_virt_addr;
+	void __iomem *stb_virt_addr;
+	void __iomem *fch_virt_addr;
+	bool msg_port;
+	u32 base_addr;
+	u32 cpu_id;
+	u32 active_ips;
+	u32 dram_size;
+	struct stb_arg stb_arg;
+/* SMU version information */
+	u8 smu_program;
+	u8 major;
+	u8 minor;
+	u8 rev;
+	struct device *dev;
+	struct pci_dev *rdev;
+	struct mutex lock; /* generic mutex lock */
+	struct dentry *dbgfs_dir;
+};
+
+int amd_pmc_s2d_init(struct amd_pmc_dev *dev);
+int amd_pmc_send_cmd(struct amd_pmc_dev *dev, u32 arg, u32 *data, u8 msg, bool ret);
+#ifdef CONFIG_SUSPEND
+int amd_pmc_write_stb(struct amd_pmc_dev *dev, u32 data);
+#endif
+
+extern const struct file_operations amd_pmc_stb_debugfs_fops;
+extern const struct file_operations amd_pmc_stb_debugfs_fops_v2;
+
+#endif /* PMC_H */
-- 
2.53.0

[PATCH 6.1.y 2/3] platform/x86/amd/pmc: Isolate STB code changes to a new file

[Sasha Levin]

From: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>

[ Upstream commit 3279f7a6b7d42374897d3b818630602f0ff56521 ]

Since S2D (Spill to DRAM) uses different message port offsets compared to
PMC message offsets for communication with PMFW, relocate the S2D macros
from pmc.c to a new file, mp1_stb.c, for better code organization.

Following this change, it is logical to introduce a new structure,
"struct stb_arg," to pass the message, argument, and response offset
details to PMFW via the amd_pmc_send_cmd() call. Additionally, move the
s2d_msg_id member from amd_pmc_dev into the new structure.

Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Co-developed-by: Sanket Goswami <Sanket.Goswami@amd.com>
Signed-off-by: Sanket Goswami <Sanket.Goswami@amd.com>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Link: https://lore.kernel.org/r/20241108070822.3912689-6-Shyam-sundar.S-k@amd.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

[Backport dependency for 0225c1d637687 to Linux 6.1]
The preceding STB split already provides stb_arg.s2d_msg_id and the S2D
initializer context needed by the target. Extend that existing structure
with message, argument and response offsets, move the S2D register macros
to mp1_stb.c, and use those offsets in the PMC command and register-dump
paths.

Initialize the offsets in the existing amd_pmc_s2d_init() before selecting
the S2D message port. The upstream amd_is_stb_supported() helper is absent
here, so do not introduce it or the unrelated newer platform, MP2 and
enhanced STB debugfs code. Preserve the stable CPU gating, command ID,
zero-address check and common message-port restoration. No functions are
added. The unmodified target applies cleanly through a three-way apply.

Stable-dep-of: 0225c1d63768 ("platform/x86/amd/pmc: Propagate SMU errors and validate S2D address")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/platform/x86/amd/pmc/mp1_stb.c |  8 ++++++++
 drivers/platform/x86/amd/pmc/pmc.c     | 21 ++++++++-------------
 drivers/platform/x86/amd/pmc/pmc.h     |  3 +++
 3 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/drivers/platform/x86/amd/pmc/mp1_stb.c b/drivers/platform/x86/amd/pmc/mp1_stb.c
index 52fc05a1bad68..351b724dc303b 100644
--- a/drivers/platform/x86/amd/pmc/mp1_stb.c
+++ b/drivers/platform/x86/amd/pmc/mp1_stb.c
@@ -31,6 +31,11 @@
 /* STB Spill to DRAM Message Definition */
 #define STB_SPILL_TO_DRAM		0xBE
 
+/* STB S2D(Spill to DRAM) has different message port offset */
+#define AMD_S2D_REGISTER_MESSAGE	0xA20
+#define AMD_S2D_REGISTER_RESPONSE	0xA80
+#define AMD_S2D_REGISTER_ARGUMENT	0xA88
+
 enum s2d_arg {
 	S2D_TELEMETRY_SIZE = 0x01,
 	S2D_PHYS_ADDR_LOW,
@@ -159,6 +164,9 @@ int amd_pmc_s2d_init(struct amd_pmc_dev *dev)
 	int ret = 0;
 
 	dev->stb_arg.s2d_msg_id = STB_SPILL_TO_DRAM;
+	dev->stb_arg.msg = AMD_S2D_REGISTER_MESSAGE;
+	dev->stb_arg.arg = AMD_S2D_REGISTER_ARGUMENT;
+	dev->stb_arg.resp = AMD_S2D_REGISTER_RESPONSE;
 
 	/* Spill to DRAM feature uses separate SMU message port */
 	dev->msg_port = MSG_PORT_S2D;
diff --git a/drivers/platform/x86/amd/pmc/pmc.c b/drivers/platform/x86/amd/pmc/pmc.c
index 4740476df007b..859f2f17078b7 100644
--- a/drivers/platform/x86/amd/pmc/pmc.c
+++ b/drivers/platform/x86/amd/pmc/pmc.c
@@ -44,11 +44,6 @@
 #define AMD_PMC_STB_S2IDLE_RESTORE	0xC6000002
 #define AMD_PMC_STB_S2IDLE_CHECK	0xC6000003
 
-/* STB S2D(Spill to DRAM) has different message port offset */
-#define AMD_S2D_REGISTER_MESSAGE	0xA20
-#define AMD_S2D_REGISTER_RESPONSE	0xA80
-#define AMD_S2D_REGISTER_ARGUMENT	0xA88
-
 /* Base address of SMU for mapping physical address to virtual address */
 #define AMD_PMC_MAPPING_SIZE		0x01000
 #define AMD_PMC_BASE_ADDR_OFFSET	0x10000
@@ -438,10 +433,10 @@ static void amd_pmc_dump_registers(struct amd_pmc_dev *dev)
 {
 	u32 value, message, argument, response;
 
-	if (dev->msg_port) {
-		message = AMD_S2D_REGISTER_MESSAGE;
-		argument = AMD_S2D_REGISTER_ARGUMENT;
-		response = AMD_S2D_REGISTER_RESPONSE;
+	if (dev->msg_port == MSG_PORT_S2D) {
+		message = dev->stb_arg.msg;
+		argument = dev->stb_arg.arg;
+		response = dev->stb_arg.resp;
 	} else {
 		message = AMD_PMC_REGISTER_MESSAGE;
 		argument = AMD_PMC_REGISTER_ARGUMENT;
@@ -465,10 +460,10 @@ int amd_pmc_send_cmd(struct amd_pmc_dev *dev, u32 arg, u32 *data, u8 msg, bool r
 
 	mutex_lock(&dev->lock);
 
-	if (dev->msg_port) {
-		message = AMD_S2D_REGISTER_MESSAGE;
-		argument = AMD_S2D_REGISTER_ARGUMENT;
-		response = AMD_S2D_REGISTER_RESPONSE;
+	if (dev->msg_port == MSG_PORT_S2D) {
+		message = dev->stb_arg.msg;
+		argument = dev->stb_arg.arg;
+		response = dev->stb_arg.resp;
 	} else {
 		message = AMD_PMC_REGISTER_MESSAGE;
 		argument = AMD_PMC_REGISTER_ARGUMENT;
diff --git a/drivers/platform/x86/amd/pmc/pmc.h b/drivers/platform/x86/amd/pmc/pmc.h
index f372321eb37a0..265216dcec90c 100644
--- a/drivers/platform/x86/amd/pmc/pmc.h
+++ b/drivers/platform/x86/amd/pmc/pmc.h
@@ -12,6 +12,9 @@ enum s2d_msg_port {
 
 struct stb_arg {
 	u32 s2d_msg_id;
+	u32 msg;
+	u32 arg;
+	u32 resp;
 };
 
 struct amd_pmc_dev {
-- 
2.53.0

[PATCH 6.1.y 3/3] platform/x86/amd/pmc: Propagate SMU errors and validate S2D address

[Sasha Levin]

From: Mario Limonciello <mario.limonciello@amd.com>

[ Upstream commit 0225c1d637687b03726f00ac65b6def843d2c464 ]

amd_stb_s2d_init() discards the return value of several S2D SMU commands.
When the SMU refuses a command (e.g. "SMU cmd failed. err: 0xff") the
failure is only noticed indirectly - if at all - and reported as -EIO,
masking the real error.

More seriously, the S2D_PHYS_ADDR_LOW/HIGH return values are ignored, so
on failure phys_addr_low/hi are left uninitialised and the assembled
address is passed straight to devm_ioremap().  When the SMU leaves them at
zero this maps physical address 0 and trips the ioremap-on-RAM warning:

  amd_pmc AMDI000B:00: SMU cmd failed. err: 0xff
  ioremap on RAM at 0x0000000000000000 - 0x0000000000ffffff
  WARNING: CPU: 13 PID: 4592 at arch/x86/mm/ioremap.c:...

Check the return value of each SMU command and propagate it, and reject a
zero physical address before calling devm_ioremap().

Reported-by: Francis De Brabandere <francisdb@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221759
Tested-by: Francis De Brabandere <francisdb@gmail.com>
Fixes: 3d7d407dfb05 ("platform/x86: amd-pmc: Add support for AMD Spill to DRAM STB feature")
Cc: stable@vger.kernel.org
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://patch.msgid.link/20260721181756.143084-4-mario.limonciello@amd.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/platform/x86/amd/pmc/mp1_stb.c | 31 +++++++++++++++++---------
 1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/drivers/platform/x86/amd/pmc/mp1_stb.c b/drivers/platform/x86/amd/pmc/mp1_stb.c
index 351b724dc303b..53e9514a924f5 100644
--- a/drivers/platform/x86/amd/pmc/mp1_stb.c
+++ b/drivers/platform/x86/amd/pmc/mp1_stb.c
@@ -171,20 +171,28 @@ int amd_pmc_s2d_init(struct amd_pmc_dev *dev)
 	/* Spill to DRAM feature uses separate SMU message port */
 	dev->msg_port = MSG_PORT_S2D;
 
-	amd_pmc_send_cmd(dev, S2D_TELEMETRY_SIZE, &size, dev->stb_arg.s2d_msg_id, true);
+	ret = amd_pmc_send_cmd(dev, S2D_TELEMETRY_SIZE, &size, dev->stb_arg.s2d_msg_id, true);
+	if (ret)
+		goto out;
 	if (size != S2D_TELEMETRY_BYTES_MAX) {
 		ret = -EIO;
 		goto out;
 	}
 
-	/* Get DRAM size */
-	ret = amd_pmc_send_cmd(dev, S2D_DRAM_SIZE, &dev->dram_size, dev->stb_arg.s2d_msg_id, true);
-	if (ret || !dev->dram_size)
+	/* Get DRAM size; fall back to the default if the query fails */
+	if (amd_pmc_send_cmd(dev, S2D_DRAM_SIZE, &dev->dram_size, dev->stb_arg.s2d_msg_id, true) ||
+	    !dev->dram_size)
 		dev->dram_size = S2D_TELEMETRY_DRAMBYTES_MAX;
 
 	/* Get STB DRAM address */
-	amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_LOW, &phys_addr_low, dev->stb_arg.s2d_msg_id, true);
-	amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_HIGH, &phys_addr_hi, dev->stb_arg.s2d_msg_id, true);
+	ret = amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_LOW, &phys_addr_low,
+			       dev->stb_arg.s2d_msg_id, true);
+	if (ret)
+		goto out;
+	ret = amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_HIGH, &phys_addr_hi,
+			       dev->stb_arg.s2d_msg_id, true);
+	if (ret)
+		goto out;
 
 	if (!phys_addr_hi && !phys_addr_low) {
 		dev_err(dev->dev, "STB is not enabled on the system; disable enable_stb or contact system vendor\n");
@@ -193,14 +201,15 @@ int amd_pmc_s2d_init(struct amd_pmc_dev *dev)
 	}
 
 	stb_phys_addr = ((u64)phys_addr_hi << 32 | phys_addr_low);
-
-	dev->stb_virt_addr = devm_ioremap(dev->dev, stb_phys_addr, dev->dram_size);
-	if (!dev->stb_virt_addr) {
-		ret = -ENOMEM;
+	if (!stb_phys_addr) {
+		dev_err(dev->dev, "S2D phys addr query returned invalid address\n");
+		ret = -ENXIO;
 		goto out;
 	}
 
-	ret = 0;
+	dev->stb_virt_addr = devm_ioremap(dev->dev, stb_phys_addr, dev->dram_size);
+	if (!dev->stb_virt_addr)
+		ret = -ENOMEM;
 
 out:
 	/* Restore the default message port for subsequent SMU operations */
-- 
2.53.0