FAILED: patch "[PATCH] platform/x86/amd/pmc: Propagate SMU errors and validate S2D" failed to apply to 6.12-stable tree

FAILED: patch "[PATCH] platform/x86/amd/pmc: Propagate SMU errors and validate S2D" failed to apply to 6.12-stable tree

[gregkh]

The patch below does not apply to the 6.12-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-6.12.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 '2026090316-rogue-eggnog-a086@gregkh' --subject-prefix 'PATCH 6.12.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 6.12.y 2/4] 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>

Stable backport adaptation:
Preserve the delay_suspend module parameter and the existing stable PMC
workarounds while moving the STB implementation out of pmc.c.

Rename the existing initializer to amd_stb_s2d_init(), define the two
message-port constants, and move s2d_msg_id into a minimal struct stb_arg.
These are the interfaces needed for 9cef693bce96 to apply unchanged; the
later upstream helper functions and unrelated platform changes are not
needed here. No new functions are introduced.

Retain the existing zero STB physical-address check omitted by the upstream
move, and restore MSG_PORT_PMC before its -EINVAL return. This preserves
the stable validation without leaving an extra mailbox error path outside
the target fix.

Stable-dep-of: 9cef693bce96 ("platform/x86/amd/pmc: Restore msg_port on amd_stb_s2d_init() error paths")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/platform/x86/amd/pmc/Makefile  |   2 +-
 drivers/platform/x86/amd/pmc/mp1_stb.c | 302 +++++++++++++++++++++++++
 drivers/platform/x86/amd/pmc/pmc.c     | 285 +----------------------
 drivers/platform/x86/amd/pmc/pmc.h     |  16 +-
 4 files changed, 320 insertions(+), 285 deletions(-)
 create mode 100644 drivers/platform/x86/amd/pmc/mp1_stb.c

diff --git a/drivers/platform/x86/amd/pmc/Makefile b/drivers/platform/x86/amd/pmc/Makefile
index f1d9ab19d24c2..255d94ddf9990 100644
--- a/drivers/platform/x86/amd/pmc/Makefile
+++ b/drivers/platform/x86/amd/pmc/Makefile
@@ -4,6 +4,6 @@
 # AMD Power Management Controller Driver
 #
 
-amd-pmc-objs := pmc.o pmc-quirks.o
+amd-pmc-objs := pmc.o pmc-quirks.o mp1_stb.o
 obj-$(CONFIG_AMD_PMC) += amd-pmc.o
 amd-pmc-$(CONFIG_AMD_MP2_STB) += mp2_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..53665d6d9c63a
--- /dev/null
+++ b/drivers/platform/x86/amd/pmc/mp1_stb.c
@@ -0,0 +1,302 @@
+// 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/seq_file.h>
+#include <linux/uaccess.h>
+
+#include "pmc.h"
+
+/* STB Spill to DRAM Parameters */
+#define S2D_TELEMETRY_DRAMBYTES_MAX	0x1000000
+#define S2D_TELEMETRY_BYTES_MAX		0x100000U
+#define S2D_RSVD_RAM_SPACE		0x100000
+
+/* STB Registers */
+#define AMD_PMC_STB_PMI_0		0x03E30600
+#define AMD_PMC_STB_DUMMY_PC	0xC6000007
+
+/* STB Spill to DRAM Message Definition */
+#define STB_FORCE_FLUSH_DATA		0xCF
+#define FIFO_SIZE		4096
+
+static bool enable_stb;
+module_param(enable_stb, bool, 0644);
+MODULE_PARM_DESC(enable_stb, "Enable the STB debug mechanism");
+
+static bool dump_custom_stb;
+module_param(dump_custom_stb, bool, 0644);
+MODULE_PARM_DESC(dump_custom_stb, "Enable to dump full STB buffer");
+
+enum s2d_arg {
+	S2D_TELEMETRY_SIZE = 0x01,
+	S2D_PHYS_ADDR_LOW,
+	S2D_PHYS_ADDR_HIGH,
+	S2D_NUM_SAMPLES,
+	S2D_DRAM_SIZE,
+};
+
+struct amd_pmc_stb_v2_data {
+	size_t size;
+	u8 data[] __counted_by(size);
+};
+
+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;
+}
+
+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;
+}
+
+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,
+};
+
+/* Enhanced STB Firmware Reporting Mechanism */
+static int amd_pmc_stb_handle_efr(struct file *filp)
+{
+	struct amd_pmc_dev *dev = filp->f_inode->i_private;
+	struct amd_pmc_stb_v2_data *stb_data_arr;
+	u32 fsize;
+
+	fsize = dev->dram_size - S2D_RSVD_RAM_SPACE;
+	stb_data_arr = kmalloc(struct_size(stb_data_arr, data, fsize), GFP_KERNEL);
+	if (!stb_data_arr)
+		return -ENOMEM;
+
+	stb_data_arr->size = fsize;
+	memcpy_fromio(stb_data_arr->data, dev->stb_virt_addr, fsize);
+	filp->private_data = stb_data_arr;
+
+	return 0;
+}
+
+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 fsize, num_samples, val, stb_rdptr_offset = 0;
+	struct amd_pmc_stb_v2_data *stb_data_arr;
+	int ret;
+
+	/* Write dummy postcode while reading the STB buffer */
+	ret = amd_pmc_write_stb(dev, AMD_PMC_STB_DUMMY_PC);
+	if (ret)
+		dev_err(dev->dev, "error writing to STB: %d\n", ret);
+
+	/* Spill to DRAM num_samples uses separate SMU message port */
+	dev->msg_port = MSG_PORT_S2D;
+
+	ret = amd_pmc_send_cmd(dev, 0, &val, STB_FORCE_FLUSH_DATA, 1);
+	if (ret)
+		dev_dbg_once(dev->dev, "S2D force flush not supported: %d\n", ret);
+
+	/*
+	 * We have a custom stb size and the PMFW is supposed to give
+	 * the enhanced dram size. Note that we land here only for the
+	 * platforms that support enhanced dram size reporting.
+	 */
+	if (dump_custom_stb)
+		return amd_pmc_stb_handle_efr(filp);
+
+	/* Get the num_samples to calculate the last push location */
+	ret = amd_pmc_send_cmd(dev, S2D_NUM_SAMPLES, &num_samples, dev->stb_arg.s2d_msg_id, true);
+	/* Clear msg_port for other SMU operation */
+	dev->msg_port = MSG_PORT_PMC;
+	if (ret) {
+		dev_err(dev->dev, "error: S2D_NUM_SAMPLES not supported : %d\n", ret);
+		return ret;
+	}
+
+	fsize = min(num_samples, S2D_TELEMETRY_BYTES_MAX);
+	stb_data_arr = kmalloc(struct_size(stb_data_arr, data, fsize), GFP_KERNEL);
+	if (!stb_data_arr)
+		return -ENOMEM;
+
+	stb_data_arr->size = fsize;
+
+	/*
+	 * Start capturing data from the last push location.
+	 * This is for general cases, where the stb limits
+	 * are meant for standard usage.
+	 */
+	if (num_samples > S2D_TELEMETRY_BYTES_MAX) {
+		/* First read oldest data starting 1 behind last write till end of ringbuffer */
+		stb_rdptr_offset = num_samples % S2D_TELEMETRY_BYTES_MAX;
+		fsize = S2D_TELEMETRY_BYTES_MAX - stb_rdptr_offset;
+
+		memcpy_fromio(stb_data_arr->data, dev->stb_virt_addr + stb_rdptr_offset, fsize);
+		/* Second copy the newer samples from offset 0 - last write */
+		memcpy_fromio(stb_data_arr->data + fsize, dev->stb_virt_addr, stb_rdptr_offset);
+	} else {
+		memcpy_fromio(stb_data_arr->data, dev->stb_virt_addr, fsize);
+	}
+
+	filp->private_data = stb_data_arr;
+
+	return 0;
+}
+
+static ssize_t amd_pmc_stb_debugfs_read_v2(struct file *filp, char __user *buf, size_t size,
+					   loff_t *pos)
+{
+	struct amd_pmc_stb_v2_data *data = filp->private_data;
+
+	return simple_read_from_buffer(buf, size, pos, data->data, data->size);
+}
+
+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 bool amd_pmc_is_stb_supported(struct amd_pmc_dev *dev)
+{
+	switch (dev->cpu_id) {
+	case AMD_CPU_ID_YC:
+	case AMD_CPU_ID_CB:
+		dev->stb_arg.s2d_msg_id = 0xBE;
+		return true;
+	case AMD_CPU_ID_PS:
+		dev->stb_arg.s2d_msg_id = 0x85;
+		return true;
+	case PCI_DEVICE_ID_AMD_1AH_M20H_ROOT:
+	case PCI_DEVICE_ID_AMD_1AH_M60H_ROOT:
+		dev->stb_arg.s2d_msg_id = 0xDE;
+		return true;
+	default:
+		return false;
+	}
+}
+
+int amd_stb_s2d_init(struct amd_pmc_dev *dev)
+{
+	u32 phys_addr_low, phys_addr_hi;
+	u64 stb_phys_addr;
+	u32 size = 0;
+	int ret;
+
+	if (!enable_stb)
+		return 0;
+
+	if (amd_pmc_is_stb_supported(dev)) {
+		debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
+				    &amd_pmc_stb_debugfs_fops_v2);
+	} else {
+		debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
+				    &amd_pmc_stb_debugfs_fops);
+		return 0;
+	}
+
+	/* 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)
+		return -EIO;
+
+	/* 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");
+		dev->msg_port = MSG_PORT_PMC;
+		return -EINVAL;
+	}
+
+	stb_phys_addr = ((u64)phys_addr_hi << 32 | phys_addr_low);
+
+	/* Clear msg_port for other SMU operation */
+	dev->msg_port = MSG_PORT_PMC;
+
+	dev->stb_virt_addr = devm_ioremap(dev->dev, stb_phys_addr, dev->dram_size);
+	if (!dev->stb_virt_addr)
+		return -ENOMEM;
+
+	return 0;
+}
diff --git a/drivers/platform/x86/amd/pmc/pmc.c b/drivers/platform/x86/amd/pmc/pmc.c
index 91d164a3ca3bc..dccce5894ce5b 100644
--- a/drivers/platform/x86/amd/pmc/pmc.c
+++ b/drivers/platform/x86/amd/pmc/pmc.c
@@ -41,25 +41,15 @@
 #define AMD_PMC_SCRATCH_REG_1AH		0xF14
 
 /* 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
-#define AMD_PMC_STB_DUMMY_PC		0xC6000007
 
 /* 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
 
-/* STB Spill to DRAM Parameters */
-#define S2D_TELEMETRY_BYTES_MAX		0x100000U
-#define S2D_RSVD_RAM_SPACE		0x100000
-#define S2D_TELEMETRY_DRAMBYTES_MAX	0x1000000
-
-/* STB Spill to DRAM Message Definition */
-#define STB_FORCE_FLUSH_DATA		0xCF
-
 /* Base address of SMU for mapping physical address to virtual address */
 #define AMD_PMC_MAPPING_SIZE		0x01000
 #define AMD_PMC_BASE_ADDR_OFFSET	0x10000
@@ -98,7 +88,6 @@
 
 #define DELAY_MIN_US		2000
 #define DELAY_MAX_US		3000
-#define FIFO_SIZE		4096
 
 enum amd_pmc_def {
 	MSG_TEST = 0x01,
@@ -106,19 +95,6 @@ enum amd_pmc_def {
 	MSG_OS_HINT_RN,
 };
 
-enum s2d_arg {
-	S2D_TELEMETRY_SIZE = 0x01,
-	S2D_PHYS_ADDR_LOW,
-	S2D_PHYS_ADDR_HIGH,
-	S2D_NUM_SAMPLES,
-	S2D_DRAM_SIZE,
-};
-
-struct amd_pmc_stb_v2_data {
-	size_t size;
-	u8 data[] __counted_by(size);
-};
-
 struct amd_pmc_bit_map {
 	const char *name;
 	u32 bit_mask;
@@ -150,27 +126,16 @@ static const struct amd_pmc_bit_map soc15_ip_blk[] = {
 	{}
 };
 
-static bool enable_stb;
-module_param(enable_stb, bool, 0644);
-MODULE_PARM_DESC(enable_stb, "Enable the STB debug mechanism");
-
 static bool disable_workarounds;
 module_param(disable_workarounds, bool, 0644);
 MODULE_PARM_DESC(disable_workarounds, "Disable workarounds for platform bugs");
 
-static bool dump_custom_stb;
-module_param(dump_custom_stb, bool, 0644);
-MODULE_PARM_DESC(dump_custom_stb, "Enable to dump full STB buffer");
-
 static int delay_suspend = -1;
 module_param(delay_suspend, int, 0644);
 MODULE_PARM_DESC(delay_suspend,
 		 "Delays s2idle by 2.5 seconds to work around buggy ECs, often causing keyboard issues after suspend. 0: don't delay, 1: do delay, -1 (default): let amd_pmc decide. If you need this please report this to: platform-driver-x86@vger.kernel.org");
 
 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);
-static int amd_pmc_write_stb(struct amd_pmc_dev *dev, u32 data);
 
 static inline u32 amd_pmc_reg_read(struct amd_pmc_dev *dev, int reg_offset)
 {
@@ -199,155 +164,6 @@ struct smu_metrics {
 	u64 timecondition_notmet_totaltime[32];
 } __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,
-};
-
-/* Enhanced STB Firmware Reporting Mechanism */
-static int amd_pmc_stb_handle_efr(struct file *filp)
-{
-	struct amd_pmc_dev *dev = filp->f_inode->i_private;
-	struct amd_pmc_stb_v2_data *stb_data_arr;
-	u32 fsize;
-
-	fsize = dev->dram_size - S2D_RSVD_RAM_SPACE;
-	stb_data_arr = kmalloc(struct_size(stb_data_arr, data, fsize), GFP_KERNEL);
-	if (!stb_data_arr)
-		return -ENOMEM;
-
-	stb_data_arr->size = fsize;
-	memcpy_fromio(stb_data_arr->data, dev->stb_virt_addr, fsize);
-	filp->private_data = stb_data_arr;
-
-	return 0;
-}
-
-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 fsize, num_samples, val, stb_rdptr_offset = 0;
-	struct amd_pmc_stb_v2_data *stb_data_arr;
-	int ret;
-
-	/* Write dummy postcode while reading the STB buffer */
-	ret = amd_pmc_write_stb(dev, AMD_PMC_STB_DUMMY_PC);
-	if (ret)
-		dev_err(dev->dev, "error writing to STB: %d\n", ret);
-
-	/* Spill to DRAM num_samples uses separate SMU message port */
-	dev->msg_port = 1;
-
-	ret = amd_pmc_send_cmd(dev, 0, &val, STB_FORCE_FLUSH_DATA, 1);
-	if (ret)
-		dev_dbg_once(dev->dev, "S2D force flush not supported: %d\n", ret);
-
-	/*
-	 * We have a custom stb size and the PMFW is supposed to give
-	 * the enhanced dram size. Note that we land here only for the
-	 * platforms that support enhanced dram size reporting.
-	 */
-	if (dump_custom_stb)
-		return amd_pmc_stb_handle_efr(filp);
-
-	/* Get the num_samples to calculate the last push location */
-	ret = amd_pmc_send_cmd(dev, S2D_NUM_SAMPLES, &num_samples, dev->s2d_msg_id, true);
-	/* Clear msg_port for other SMU operation */
-	dev->msg_port = 0;
-	if (ret) {
-		dev_err(dev->dev, "error: S2D_NUM_SAMPLES not supported : %d\n", ret);
-		return ret;
-	}
-
-	fsize = min(num_samples, S2D_TELEMETRY_BYTES_MAX);
-	stb_data_arr = kmalloc(struct_size(stb_data_arr, data, fsize), GFP_KERNEL);
-	if (!stb_data_arr)
-		return -ENOMEM;
-
-	stb_data_arr->size = fsize;
-
-	/*
-	 * Start capturing data from the last push location.
-	 * This is for general cases, where the stb limits
-	 * are meant for standard usage.
-	 */
-	if (num_samples > S2D_TELEMETRY_BYTES_MAX) {
-		/* First read oldest data starting 1 behind last write till end of ringbuffer */
-		stb_rdptr_offset = num_samples % S2D_TELEMETRY_BYTES_MAX;
-		fsize = S2D_TELEMETRY_BYTES_MAX - stb_rdptr_offset;
-
-		memcpy_fromio(stb_data_arr->data, dev->stb_virt_addr + stb_rdptr_offset, fsize);
-		/* Second copy the newer samples from offset 0 - last write */
-		memcpy_fromio(stb_data_arr->data + fsize, dev->stb_virt_addr, stb_rdptr_offset);
-	} else {
-		memcpy_fromio(stb_data_arr->data, dev->stb_virt_addr, fsize);
-	}
-
-	filp->private_data = stb_data_arr;
-
-	return 0;
-}
-
-static ssize_t amd_pmc_stb_debugfs_read_v2(struct file *filp, char __user *buf, size_t size,
-					   loff_t *pos)
-{
-	struct amd_pmc_stb_v2_data *data = filp->private_data;
-
-	return simple_read_from_buffer(buf, size, pos, data->data, data->size);
-}
-
-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 void amd_pmc_get_ip_info(struct amd_pmc_dev *dev)
 {
 	switch (dev->cpu_id) {
@@ -357,18 +173,15 @@ static void amd_pmc_get_ip_info(struct amd_pmc_dev *dev)
 	case AMD_CPU_ID_YC:
 	case AMD_CPU_ID_CB:
 		dev->num_ips = 12;
-		dev->s2d_msg_id = 0xBE;
 		dev->smu_msg = 0x538;
 		break;
 	case AMD_CPU_ID_PS:
 		dev->num_ips = 21;
-		dev->s2d_msg_id = 0x85;
 		dev->smu_msg = 0x538;
 		break;
 	case PCI_DEVICE_ID_AMD_1AH_M20H_ROOT:
 	case PCI_DEVICE_ID_AMD_1AH_M60H_ROOT:
 		dev->num_ips = 22;
-		dev->s2d_msg_id = 0xDE;
 		dev->smu_msg = 0x938;
 		break;
 	}
@@ -634,20 +447,6 @@ static void amd_pmc_dbgfs_unregister(struct amd_pmc_dev *dev)
 	debugfs_remove_recursive(dev->dbgfs_dir);
 }
 
-static bool amd_pmc_is_stb_supported(struct amd_pmc_dev *dev)
-{
-	switch (dev->cpu_id) {
-	case AMD_CPU_ID_YC:
-	case AMD_CPU_ID_CB:
-	case AMD_CPU_ID_PS:
-	case PCI_DEVICE_ID_AMD_1AH_M20H_ROOT:
-	case PCI_DEVICE_ID_AMD_1AH_M60H_ROOT:
-		return true;
-	default:
-		return false;
-	}
-}
-
 static void amd_pmc_dbgfs_register(struct amd_pmc_dev *dev)
 {
 	dev->dbgfs_dir = debugfs_create_dir("amd_pmc", NULL);
@@ -683,7 +482,7 @@ static void amd_pmc_dump_registers(struct amd_pmc_dev *dev)
 	dev_dbg(dev->dev, "AMD_%s_REGISTER_MESSAGE:%x\n", dev->msg_port ? "S2D" : "PMC", 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;
@@ -1053,86 +852,6 @@ 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;
-	int ret;
-
-	if (!enable_stb)
-		return 0;
-
-	if (amd_pmc_is_stb_supported(dev)) {
-		debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
-				    &amd_pmc_stb_debugfs_fops_v2);
-	} else {
-		debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
-				    &amd_pmc_stb_debugfs_fops);
-		return 0;
-	}
-
-	/* Spill to DRAM feature uses separate SMU message port */
-	dev->msg_port = 1;
-
-	amd_pmc_send_cmd(dev, S2D_TELEMETRY_SIZE, &size, dev->s2d_msg_id, true);
-	if (size != S2D_TELEMETRY_BYTES_MAX)
-		return -EIO;
-
-	/* Get DRAM size */
-	ret = amd_pmc_send_cmd(dev, S2D_DRAM_SIZE, &dev->dram_size, dev->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->s2d_msg_id, true);
-	amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_HIGH, &phys_addr_hi, dev->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");
-		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, dev->dram_size);
-	if (!dev->stb_virt_addr)
-		return -ENOMEM;
-
-	return 0;
-}
-
-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;
-}
-
-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;
@@ -1200,7 +919,7 @@ static int amd_pmc_probe(struct platform_device *pdev)
 	}
 
 	amd_pmc_dbgfs_register(dev);
-	err = amd_pmc_s2d_init(dev);
+	err = amd_stb_s2d_init(dev);
 	if (err)
 		goto err_pci_dev_put;
 
diff --git a/drivers/platform/x86/amd/pmc/pmc.h b/drivers/platform/x86/amd/pmc/pmc.h
index 89f8891d3e389..a33a737441821 100644
--- a/drivers/platform/x86/amd/pmc/pmc.h
+++ b/drivers/platform/x86/amd/pmc/pmc.h
@@ -14,6 +14,11 @@
 #include <linux/types.h>
 #include <linux/mutex.h>
 
+enum s2d_msg_port {
+	MSG_PORT_PMC,
+	MSG_PORT_S2D,
+};
+
 struct amd_mp2_dev {
 	void __iomem *mmio;
 	void __iomem *vslbase;
@@ -25,6 +30,10 @@ struct amd_mp2_dev {
 	bool is_stb_data;
 };
 
+struct stb_arg {
+	u32 s2d_msg_id;
+};
+
 struct amd_pmc_dev {
 	void __iomem *regbase;
 	void __iomem *smu_virt_addr;
@@ -36,7 +45,6 @@ struct amd_pmc_dev {
 	u32 active_ips;
 	u32 dram_size;
 	u32 num_ips;
-	u32 s2d_msg_id;
 	u32 smu_msg;
 /* SMU version information */
 	u8 smu_program;
@@ -51,6 +59,7 @@ struct amd_pmc_dev {
 	bool disable_8042_wakeup;
 	bool is_first_check_after_suspend;
 	struct amd_mp2_dev *mp2;
+	struct stb_arg stb_arg;
 };
 
 void amd_pmc_process_restore_quirks(struct amd_pmc_dev *dev);
@@ -73,4 +82,9 @@ void amd_mp2_stb_deinit(struct amd_pmc_dev *dev);
 #define PCI_DEVICE_ID_AMD_1AH_M60H_ROOT 0x1122
 #define PCI_DEVICE_ID_AMD_MP2_STB	0x172c
 
+int amd_stb_s2d_init(struct amd_pmc_dev *dev);
+int amd_pmc_read_stb(struct amd_pmc_dev *dev, u32 *buf);
+int amd_pmc_write_stb(struct amd_pmc_dev *dev, u32 data);
+int amd_pmc_send_cmd(struct amd_pmc_dev *dev, u32 arg, u32 *data, u8 msg, bool ret);
+
 #endif /* PMC_H */
-- 
2.53.0

[PATCH 6.12.y 1/4] platform/x86/amd/pmc: Move STB block into amd_pmc_s2d_init()

[Sasha Levin]

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

[ Upstream commit 83ad6974dd3bf34c080b3c08d36d02ebc3bd6da8 ]

Transfer the support for STB-related file operations to the
amd_pmc_s2d_init() function, thereby consolidating the STB and S2D
(Spill to DRAM) functionality in one location. Also, relocate the
call to amd_pmc_s2d_init() to occur after the creation of the
"amd_pmc" debugfs directory. This ensures that the driver's root debugfs
directory is established beforehand.

For older platforms that supported S2D, exit immediately after creating
debugfs. These platforms may not support the PMFW messages available on
newer platforms. This adjustment is necessary due to the relocation of
debugfs creation into amd_pmc_s2d_init().

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/20241108070822.3912689-2-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>
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/pmc.c | 31 +++++++++++++++---------------
 1 file changed, 16 insertions(+), 15 deletions(-)

diff --git a/drivers/platform/x86/amd/pmc/pmc.c b/drivers/platform/x86/amd/pmc/pmc.c
index 343f75eeb7f28..91d164a3ca3bc 100644
--- a/drivers/platform/x86/amd/pmc/pmc.c
+++ b/drivers/platform/x86/amd/pmc/pmc.c
@@ -657,15 +657,6 @@ 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) {
-		if (amd_pmc_is_stb_supported(dev))
-			debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
-					    &amd_pmc_stb_debugfs_fops_v2);
-		else
-			debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
-					    &amd_pmc_stb_debugfs_fops);
-	}
 }
 
 static void amd_pmc_dump_registers(struct amd_pmc_dev *dev)
@@ -1069,6 +1060,18 @@ static int amd_pmc_s2d_init(struct amd_pmc_dev *dev)
 	u32 size = 0;
 	int ret;
 
+	if (!enable_stb)
+		return 0;
+
+	if (amd_pmc_is_stb_supported(dev)) {
+		debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
+				    &amd_pmc_stb_debugfs_fops_v2);
+	} else {
+		debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
+				    &amd_pmc_stb_debugfs_fops);
+		return 0;
+	}
+
 	/* Spill to DRAM feature uses separate SMU message port */
 	dev->msg_port = 1;
 
@@ -1187,12 +1190,6 @@ static int amd_pmc_probe(struct platform_device *pdev)
 	/* Get num of IP blocks within the SoC */
 	amd_pmc_get_ip_info(dev);
 
-	if (enable_stb && amd_pmc_is_stb_supported(dev)) {
-		err = amd_pmc_s2d_init(dev);
-		if (err)
-			goto err_pci_dev_put;
-	}
-
 	platform_set_drvdata(pdev, dev);
 	if (IS_ENABLED(CONFIG_SUSPEND)) {
 		err = acpi_register_lps0_dev(&amd_pmc_s2idle_dev_ops);
@@ -1203,6 +1200,10 @@ static int amd_pmc_probe(struct platform_device *pdev)
 	}
 
 	amd_pmc_dbgfs_register(dev);
+	err = amd_pmc_s2d_init(dev);
+	if (err)
+		goto err_pci_dev_put;
+
 	if (IS_ENABLED(CONFIG_AMD_MP2_STB))
 		amd_mp2_stb_init(dev);
 	pm_report_max_hw_sleep(U64_MAX);
-- 
2.53.0

[PATCH 6.12.y 2/4] 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>

[Stable backport: Keep the delay_suspend module parameter in pmc.c while
moving dump_custom_stb and the existing STB routines to mp1_stb.c.

Prepare the moved initializer for 0225c1d63768 by defining the PMC/S2D
port constants, nesting s2d_msg_id in stb_arg, and restoring the PMC
message port through a shared exit path. Retain the stable tree's
zero-address protection using the target's check and mapping cleanup;
do not carry over the upstream move's deletion of that protection.
Express the DRAM-size fallback without retaining its optional query
error, so a successful initialization still returns zero. The target's
SMU command error checks remain to be applied separately.

Keep the existing function names and stable interfaces. No functions or
new platform support are added.]

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/Makefile  |   2 +-
 drivers/platform/x86/amd/pmc/mp1_stb.c | 303 +++++++++++++++++++++++++
 drivers/platform/x86/amd/pmc/pmc.c     | 283 +----------------------
 drivers/platform/x86/amd/pmc/pmc.h     |  16 +-
 4 files changed, 320 insertions(+), 284 deletions(-)
 create mode 100644 drivers/platform/x86/amd/pmc/mp1_stb.c

diff --git a/drivers/platform/x86/amd/pmc/Makefile b/drivers/platform/x86/amd/pmc/Makefile
index f1d9ab19d24c2..255d94ddf9990 100644
--- a/drivers/platform/x86/amd/pmc/Makefile
+++ b/drivers/platform/x86/amd/pmc/Makefile
@@ -4,6 +4,6 @@
 # AMD Power Management Controller Driver
 #
 
-amd-pmc-objs := pmc.o pmc-quirks.o
+amd-pmc-objs := pmc.o pmc-quirks.o mp1_stb.o
 obj-$(CONFIG_AMD_PMC) += amd-pmc.o
 amd-pmc-$(CONFIG_AMD_MP2_STB) += mp2_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..f36e112cdbf0b
--- /dev/null
+++ b/drivers/platform/x86/amd/pmc/mp1_stb.c
@@ -0,0 +1,303 @@
+// 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/seq_file.h>
+#include <linux/uaccess.h>
+
+#include "pmc.h"
+
+/* STB Spill to DRAM Parameters */
+#define S2D_TELEMETRY_DRAMBYTES_MAX	0x1000000
+#define S2D_TELEMETRY_BYTES_MAX		0x100000U
+#define S2D_RSVD_RAM_SPACE		0x100000
+
+/* STB Registers */
+#define AMD_PMC_STB_PMI_0		0x03E30600
+#define AMD_PMC_STB_DUMMY_PC	0xC6000007
+
+/* STB Spill to DRAM Message Definition */
+#define STB_FORCE_FLUSH_DATA		0xCF
+#define FIFO_SIZE		4096
+
+static bool enable_stb;
+module_param(enable_stb, bool, 0644);
+MODULE_PARM_DESC(enable_stb, "Enable the STB debug mechanism");
+
+static bool dump_custom_stb;
+module_param(dump_custom_stb, bool, 0644);
+MODULE_PARM_DESC(dump_custom_stb, "Enable to dump full STB buffer");
+
+enum s2d_arg {
+	S2D_TELEMETRY_SIZE = 0x01,
+	S2D_PHYS_ADDR_LOW,
+	S2D_PHYS_ADDR_HIGH,
+	S2D_NUM_SAMPLES,
+	S2D_DRAM_SIZE,
+};
+
+struct amd_pmc_stb_v2_data {
+	size_t size;
+	u8 data[] __counted_by(size);
+};
+
+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;
+}
+
+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;
+}
+
+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,
+};
+
+/* Enhanced STB Firmware Reporting Mechanism */
+static int amd_pmc_stb_handle_efr(struct file *filp)
+{
+	struct amd_pmc_dev *dev = filp->f_inode->i_private;
+	struct amd_pmc_stb_v2_data *stb_data_arr;
+	u32 fsize;
+
+	fsize = dev->dram_size - S2D_RSVD_RAM_SPACE;
+	stb_data_arr = kmalloc(struct_size(stb_data_arr, data, fsize), GFP_KERNEL);
+	if (!stb_data_arr)
+		return -ENOMEM;
+
+	stb_data_arr->size = fsize;
+	memcpy_fromio(stb_data_arr->data, dev->stb_virt_addr, fsize);
+	filp->private_data = stb_data_arr;
+
+	return 0;
+}
+
+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 fsize, num_samples, val, stb_rdptr_offset = 0;
+	struct amd_pmc_stb_v2_data *stb_data_arr;
+	int ret;
+
+	/* Write dummy postcode while reading the STB buffer */
+	ret = amd_pmc_write_stb(dev, AMD_PMC_STB_DUMMY_PC);
+	if (ret)
+		dev_err(dev->dev, "error writing to STB: %d\n", ret);
+
+	/* Spill to DRAM num_samples uses separate SMU message port */
+	dev->msg_port = MSG_PORT_S2D;
+
+	ret = amd_pmc_send_cmd(dev, 0, &val, STB_FORCE_FLUSH_DATA, 1);
+	if (ret)
+		dev_dbg_once(dev->dev, "S2D force flush not supported: %d\n", ret);
+
+	/*
+	 * We have a custom stb size and the PMFW is supposed to give
+	 * the enhanced dram size. Note that we land here only for the
+	 * platforms that support enhanced dram size reporting.
+	 */
+	if (dump_custom_stb)
+		return amd_pmc_stb_handle_efr(filp);
+
+	/* Get the num_samples to calculate the last push location */
+	ret = amd_pmc_send_cmd(dev, S2D_NUM_SAMPLES, &num_samples, dev->stb_arg.s2d_msg_id, true);
+	/* Clear msg_port for other SMU operation */
+	dev->msg_port = MSG_PORT_PMC;
+	if (ret) {
+		dev_err(dev->dev, "error: S2D_NUM_SAMPLES not supported : %d\n", ret);
+		return ret;
+	}
+
+	fsize = min(num_samples, S2D_TELEMETRY_BYTES_MAX);
+	stb_data_arr = kmalloc(struct_size(stb_data_arr, data, fsize), GFP_KERNEL);
+	if (!stb_data_arr)
+		return -ENOMEM;
+
+	stb_data_arr->size = fsize;
+
+	/*
+	 * Start capturing data from the last push location.
+	 * This is for general cases, where the stb limits
+	 * are meant for standard usage.
+	 */
+	if (num_samples > S2D_TELEMETRY_BYTES_MAX) {
+		/* First read oldest data starting 1 behind last write till end of ringbuffer */
+		stb_rdptr_offset = num_samples % S2D_TELEMETRY_BYTES_MAX;
+		fsize = S2D_TELEMETRY_BYTES_MAX - stb_rdptr_offset;
+
+		memcpy_fromio(stb_data_arr->data, dev->stb_virt_addr + stb_rdptr_offset, fsize);
+		/* Second copy the newer samples from offset 0 - last write */
+		memcpy_fromio(stb_data_arr->data + fsize, dev->stb_virt_addr, stb_rdptr_offset);
+	} else {
+		memcpy_fromio(stb_data_arr->data, dev->stb_virt_addr, fsize);
+	}
+
+	filp->private_data = stb_data_arr;
+
+	return 0;
+}
+
+static ssize_t amd_pmc_stb_debugfs_read_v2(struct file *filp, char __user *buf, size_t size,
+					   loff_t *pos)
+{
+	struct amd_pmc_stb_v2_data *data = filp->private_data;
+
+	return simple_read_from_buffer(buf, size, pos, data->data, data->size);
+}
+
+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 bool amd_pmc_is_stb_supported(struct amd_pmc_dev *dev)
+{
+	switch (dev->cpu_id) {
+	case AMD_CPU_ID_YC:
+	case AMD_CPU_ID_CB:
+		dev->stb_arg.s2d_msg_id = 0xBE;
+		return true;
+	case AMD_CPU_ID_PS:
+		dev->stb_arg.s2d_msg_id = 0x85;
+		return true;
+	case PCI_DEVICE_ID_AMD_1AH_M20H_ROOT:
+	case PCI_DEVICE_ID_AMD_1AH_M60H_ROOT:
+		dev->stb_arg.s2d_msg_id = 0xDE;
+		return true;
+	default:
+		return false;
+	}
+}
+
+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;
+
+	if (!enable_stb)
+		return 0;
+
+	if (amd_pmc_is_stb_supported(dev)) {
+		debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
+				    &amd_pmc_stb_debugfs_fops_v2);
+	} else {
+		debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
+				    &amd_pmc_stb_debugfs_fops);
+		return 0;
+	}
+
+	/* 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; 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);
+
+	stb_phys_addr = ((u64)phys_addr_hi << 32 | phys_addr_low);
+	if (!stb_phys_addr) {
+		dev_err(dev->dev, "S2D phys addr query returned invalid address\n");
+		ret = -ENXIO;
+		goto out;
+	}
+
+	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 */
+	dev->msg_port = MSG_PORT_PMC;
+	return ret;
+}
diff --git a/drivers/platform/x86/amd/pmc/pmc.c b/drivers/platform/x86/amd/pmc/pmc.c
index 91d164a3ca3bc..ca2bf410d986a 100644
--- a/drivers/platform/x86/amd/pmc/pmc.c
+++ b/drivers/platform/x86/amd/pmc/pmc.c
@@ -41,25 +41,15 @@
 #define AMD_PMC_SCRATCH_REG_1AH		0xF14
 
 /* 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
-#define AMD_PMC_STB_DUMMY_PC		0xC6000007
 
 /* 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
 
-/* STB Spill to DRAM Parameters */
-#define S2D_TELEMETRY_BYTES_MAX		0x100000U
-#define S2D_RSVD_RAM_SPACE		0x100000
-#define S2D_TELEMETRY_DRAMBYTES_MAX	0x1000000
-
-/* STB Spill to DRAM Message Definition */
-#define STB_FORCE_FLUSH_DATA		0xCF
-
 /* Base address of SMU for mapping physical address to virtual address */
 #define AMD_PMC_MAPPING_SIZE		0x01000
 #define AMD_PMC_BASE_ADDR_OFFSET	0x10000
@@ -98,7 +88,6 @@
 
 #define DELAY_MIN_US		2000
 #define DELAY_MAX_US		3000
-#define FIFO_SIZE		4096
 
 enum amd_pmc_def {
 	MSG_TEST = 0x01,
@@ -106,19 +95,6 @@ enum amd_pmc_def {
 	MSG_OS_HINT_RN,
 };
 
-enum s2d_arg {
-	S2D_TELEMETRY_SIZE = 0x01,
-	S2D_PHYS_ADDR_LOW,
-	S2D_PHYS_ADDR_HIGH,
-	S2D_NUM_SAMPLES,
-	S2D_DRAM_SIZE,
-};
-
-struct amd_pmc_stb_v2_data {
-	size_t size;
-	u8 data[] __counted_by(size);
-};
-
 struct amd_pmc_bit_map {
 	const char *name;
 	u32 bit_mask;
@@ -150,27 +126,16 @@ static const struct amd_pmc_bit_map soc15_ip_blk[] = {
 	{}
 };
 
-static bool enable_stb;
-module_param(enable_stb, bool, 0644);
-MODULE_PARM_DESC(enable_stb, "Enable the STB debug mechanism");
-
 static bool disable_workarounds;
 module_param(disable_workarounds, bool, 0644);
 MODULE_PARM_DESC(disable_workarounds, "Disable workarounds for platform bugs");
 
-static bool dump_custom_stb;
-module_param(dump_custom_stb, bool, 0644);
-MODULE_PARM_DESC(dump_custom_stb, "Enable to dump full STB buffer");
-
 static int delay_suspend = -1;
 module_param(delay_suspend, int, 0644);
 MODULE_PARM_DESC(delay_suspend,
 		 "Delays s2idle by 2.5 seconds to work around buggy ECs, often causing keyboard issues after suspend. 0: don't delay, 1: do delay, -1 (default): let amd_pmc decide. If you need this please report this to: platform-driver-x86@vger.kernel.org");
 
 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);
-static int amd_pmc_write_stb(struct amd_pmc_dev *dev, u32 data);
 
 static inline u32 amd_pmc_reg_read(struct amd_pmc_dev *dev, int reg_offset)
 {
@@ -199,155 +164,6 @@ struct smu_metrics {
 	u64 timecondition_notmet_totaltime[32];
 } __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,
-};
-
-/* Enhanced STB Firmware Reporting Mechanism */
-static int amd_pmc_stb_handle_efr(struct file *filp)
-{
-	struct amd_pmc_dev *dev = filp->f_inode->i_private;
-	struct amd_pmc_stb_v2_data *stb_data_arr;
-	u32 fsize;
-
-	fsize = dev->dram_size - S2D_RSVD_RAM_SPACE;
-	stb_data_arr = kmalloc(struct_size(stb_data_arr, data, fsize), GFP_KERNEL);
-	if (!stb_data_arr)
-		return -ENOMEM;
-
-	stb_data_arr->size = fsize;
-	memcpy_fromio(stb_data_arr->data, dev->stb_virt_addr, fsize);
-	filp->private_data = stb_data_arr;
-
-	return 0;
-}
-
-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 fsize, num_samples, val, stb_rdptr_offset = 0;
-	struct amd_pmc_stb_v2_data *stb_data_arr;
-	int ret;
-
-	/* Write dummy postcode while reading the STB buffer */
-	ret = amd_pmc_write_stb(dev, AMD_PMC_STB_DUMMY_PC);
-	if (ret)
-		dev_err(dev->dev, "error writing to STB: %d\n", ret);
-
-	/* Spill to DRAM num_samples uses separate SMU message port */
-	dev->msg_port = 1;
-
-	ret = amd_pmc_send_cmd(dev, 0, &val, STB_FORCE_FLUSH_DATA, 1);
-	if (ret)
-		dev_dbg_once(dev->dev, "S2D force flush not supported: %d\n", ret);
-
-	/*
-	 * We have a custom stb size and the PMFW is supposed to give
-	 * the enhanced dram size. Note that we land here only for the
-	 * platforms that support enhanced dram size reporting.
-	 */
-	if (dump_custom_stb)
-		return amd_pmc_stb_handle_efr(filp);
-
-	/* Get the num_samples to calculate the last push location */
-	ret = amd_pmc_send_cmd(dev, S2D_NUM_SAMPLES, &num_samples, dev->s2d_msg_id, true);
-	/* Clear msg_port for other SMU operation */
-	dev->msg_port = 0;
-	if (ret) {
-		dev_err(dev->dev, "error: S2D_NUM_SAMPLES not supported : %d\n", ret);
-		return ret;
-	}
-
-	fsize = min(num_samples, S2D_TELEMETRY_BYTES_MAX);
-	stb_data_arr = kmalloc(struct_size(stb_data_arr, data, fsize), GFP_KERNEL);
-	if (!stb_data_arr)
-		return -ENOMEM;
-
-	stb_data_arr->size = fsize;
-
-	/*
-	 * Start capturing data from the last push location.
-	 * This is for general cases, where the stb limits
-	 * are meant for standard usage.
-	 */
-	if (num_samples > S2D_TELEMETRY_BYTES_MAX) {
-		/* First read oldest data starting 1 behind last write till end of ringbuffer */
-		stb_rdptr_offset = num_samples % S2D_TELEMETRY_BYTES_MAX;
-		fsize = S2D_TELEMETRY_BYTES_MAX - stb_rdptr_offset;
-
-		memcpy_fromio(stb_data_arr->data, dev->stb_virt_addr + stb_rdptr_offset, fsize);
-		/* Second copy the newer samples from offset 0 - last write */
-		memcpy_fromio(stb_data_arr->data + fsize, dev->stb_virt_addr, stb_rdptr_offset);
-	} else {
-		memcpy_fromio(stb_data_arr->data, dev->stb_virt_addr, fsize);
-	}
-
-	filp->private_data = stb_data_arr;
-
-	return 0;
-}
-
-static ssize_t amd_pmc_stb_debugfs_read_v2(struct file *filp, char __user *buf, size_t size,
-					   loff_t *pos)
-{
-	struct amd_pmc_stb_v2_data *data = filp->private_data;
-
-	return simple_read_from_buffer(buf, size, pos, data->data, data->size);
-}
-
-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 void amd_pmc_get_ip_info(struct amd_pmc_dev *dev)
 {
 	switch (dev->cpu_id) {
@@ -357,18 +173,15 @@ static void amd_pmc_get_ip_info(struct amd_pmc_dev *dev)
 	case AMD_CPU_ID_YC:
 	case AMD_CPU_ID_CB:
 		dev->num_ips = 12;
-		dev->s2d_msg_id = 0xBE;
 		dev->smu_msg = 0x538;
 		break;
 	case AMD_CPU_ID_PS:
 		dev->num_ips = 21;
-		dev->s2d_msg_id = 0x85;
 		dev->smu_msg = 0x538;
 		break;
 	case PCI_DEVICE_ID_AMD_1AH_M20H_ROOT:
 	case PCI_DEVICE_ID_AMD_1AH_M60H_ROOT:
 		dev->num_ips = 22;
-		dev->s2d_msg_id = 0xDE;
 		dev->smu_msg = 0x938;
 		break;
 	}
@@ -634,20 +447,6 @@ static void amd_pmc_dbgfs_unregister(struct amd_pmc_dev *dev)
 	debugfs_remove_recursive(dev->dbgfs_dir);
 }
 
-static bool amd_pmc_is_stb_supported(struct amd_pmc_dev *dev)
-{
-	switch (dev->cpu_id) {
-	case AMD_CPU_ID_YC:
-	case AMD_CPU_ID_CB:
-	case AMD_CPU_ID_PS:
-	case PCI_DEVICE_ID_AMD_1AH_M20H_ROOT:
-	case PCI_DEVICE_ID_AMD_1AH_M60H_ROOT:
-		return true;
-	default:
-		return false;
-	}
-}
-
 static void amd_pmc_dbgfs_register(struct amd_pmc_dev *dev)
 {
 	dev->dbgfs_dir = debugfs_create_dir("amd_pmc", NULL);
@@ -683,7 +482,7 @@ static void amd_pmc_dump_registers(struct amd_pmc_dev *dev)
 	dev_dbg(dev->dev, "AMD_%s_REGISTER_MESSAGE:%x\n", dev->msg_port ? "S2D" : "PMC", 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;
@@ -1053,86 +852,6 @@ 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;
-	int ret;
-
-	if (!enable_stb)
-		return 0;
-
-	if (amd_pmc_is_stb_supported(dev)) {
-		debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
-				    &amd_pmc_stb_debugfs_fops_v2);
-	} else {
-		debugfs_create_file("stb_read", 0644, dev->dbgfs_dir, dev,
-				    &amd_pmc_stb_debugfs_fops);
-		return 0;
-	}
-
-	/* Spill to DRAM feature uses separate SMU message port */
-	dev->msg_port = 1;
-
-	amd_pmc_send_cmd(dev, S2D_TELEMETRY_SIZE, &size, dev->s2d_msg_id, true);
-	if (size != S2D_TELEMETRY_BYTES_MAX)
-		return -EIO;
-
-	/* Get DRAM size */
-	ret = amd_pmc_send_cmd(dev, S2D_DRAM_SIZE, &dev->dram_size, dev->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->s2d_msg_id, true);
-	amd_pmc_send_cmd(dev, S2D_PHYS_ADDR_HIGH, &phys_addr_hi, dev->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");
-		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, dev->dram_size);
-	if (!dev->stb_virt_addr)
-		return -ENOMEM;
-
-	return 0;
-}
-
-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;
-}
-
-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
index 89f8891d3e389..24c7aab40f19f 100644
--- a/drivers/platform/x86/amd/pmc/pmc.h
+++ b/drivers/platform/x86/amd/pmc/pmc.h
@@ -14,6 +14,15 @@
 #include <linux/types.h>
 #include <linux/mutex.h>
 
+enum s2d_msg_port {
+	MSG_PORT_PMC,
+	MSG_PORT_S2D,
+};
+
+struct stb_arg {
+	u32 s2d_msg_id;
+};
+
 struct amd_mp2_dev {
 	void __iomem *mmio;
 	void __iomem *vslbase;
@@ -36,7 +45,6 @@ struct amd_pmc_dev {
 	u32 active_ips;
 	u32 dram_size;
 	u32 num_ips;
-	u32 s2d_msg_id;
 	u32 smu_msg;
 /* SMU version information */
 	u8 smu_program;
@@ -51,6 +59,7 @@ struct amd_pmc_dev {
 	bool disable_8042_wakeup;
 	bool is_first_check_after_suspend;
 	struct amd_mp2_dev *mp2;
+	struct stb_arg stb_arg;
 };
 
 void amd_pmc_process_restore_quirks(struct amd_pmc_dev *dev);
@@ -73,4 +82,9 @@ void amd_mp2_stb_deinit(struct amd_pmc_dev *dev);
 #define PCI_DEVICE_ID_AMD_1AH_M60H_ROOT 0x1122
 #define PCI_DEVICE_ID_AMD_MP2_STB	0x172c
 
+int amd_pmc_s2d_init(struct amd_pmc_dev *dev);
+int amd_pmc_read_stb(struct amd_pmc_dev *dev, u32 *buf);
+int amd_pmc_write_stb(struct amd_pmc_dev *dev, u32 data);
+int amd_pmc_send_cmd(struct amd_pmc_dev *dev, u32 arg, u32 *data, u8 msg, bool ret);
+
 #endif /* PMC_H */
-- 
2.53.0

[PATCH 6.12.y 3/4] 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>

[Stable backport: The preceding STB move already introduced struct
stb_arg and converted all s2d_msg_id users. Extend that existing structure
with the message, argument and response offsets instead of defining it
again. Initialize those offsets in the existing STB support check and
use them in the PMC command and register-dump paths.

Keep the stable amd_pmc_* function names and bool message-port field.
Preserve the initializer's shared PMC-port restore path, zero-address
validation, mapping cleanup and successful DRAM-size fallback. Drop the
upstream hunks that repeat the earlier s2d_msg_id conversion or would
undo those preparations. No functions or platform support are added.

Target 0225c1d63768 applies cleanly with a three-way application and adds
the remaining SMU command error checks.]

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 | 17 ++++++++++++++---
 drivers/platform/x86/amd/pmc/pmc.c     | 21 ++++++++-------------
 drivers/platform/x86/amd/pmc/pmc.h     |  3 +++
 3 files changed, 25 insertions(+), 16 deletions(-)

diff --git a/drivers/platform/x86/amd/pmc/mp1_stb.c b/drivers/platform/x86/amd/pmc/mp1_stb.c
index f36e112cdbf0b..0eeec64df259d 100644
--- a/drivers/platform/x86/amd/pmc/mp1_stb.c
+++ b/drivers/platform/x86/amd/pmc/mp1_stb.c
@@ -31,6 +31,11 @@
 #define STB_FORCE_FLUSH_DATA		0xCF
 #define FIFO_SIZE		4096
 
+/* 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
+
 static bool enable_stb;
 module_param(enable_stb, bool, 0644);
 MODULE_PARM_DESC(enable_stb, "Enable the STB debug mechanism");
@@ -235,17 +240,23 @@ static bool amd_pmc_is_stb_supported(struct amd_pmc_dev *dev)
 	case AMD_CPU_ID_YC:
 	case AMD_CPU_ID_CB:
 		dev->stb_arg.s2d_msg_id = 0xBE;
-		return true;
+		break;
 	case AMD_CPU_ID_PS:
 		dev->stb_arg.s2d_msg_id = 0x85;
-		return true;
+		break;
 	case PCI_DEVICE_ID_AMD_1AH_M20H_ROOT:
 	case PCI_DEVICE_ID_AMD_1AH_M60H_ROOT:
 		dev->stb_arg.s2d_msg_id = 0xDE;
-		return true;
+		break;
 	default:
 		return false;
 	}
+
+	dev->stb_arg.msg = AMD_S2D_REGISTER_MESSAGE;
+	dev->stb_arg.arg = AMD_S2D_REGISTER_ARGUMENT;
+	dev->stb_arg.resp = AMD_S2D_REGISTER_RESPONSE;
+
+	return true;
 }
 
 int amd_pmc_s2d_init(struct amd_pmc_dev *dev)
diff --git a/drivers/platform/x86/amd/pmc/pmc.c b/drivers/platform/x86/amd/pmc/pmc.c
index ca2bf410d986a..443b8b94a978f 100644
--- a/drivers/platform/x86/amd/pmc/pmc.c
+++ b/drivers/platform/x86/amd/pmc/pmc.c
@@ -45,11 +45,6 @@
 #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
@@ -462,10 +457,10 @@ 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 = dev->smu_msg;
 		argument = AMD_PMC_REGISTER_ARGUMENT;
@@ -489,10 +484,10 @@ 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 = dev->smu_msg;
 		argument = AMD_PMC_REGISTER_ARGUMENT;
diff --git a/drivers/platform/x86/amd/pmc/pmc.h b/drivers/platform/x86/amd/pmc/pmc.h
index 24c7aab40f19f..0b8c0c179d657 100644
--- a/drivers/platform/x86/amd/pmc/pmc.h
+++ b/drivers/platform/x86/amd/pmc/pmc.h
@@ -21,6 +21,9 @@ enum s2d_msg_port {
 
 struct stb_arg {
 	u32 s2d_msg_id;
+	u32 msg;
+	u32 arg;
+	u32 resp;
 };
 
 struct amd_mp2_dev {
-- 
2.53.0

[PATCH 6.12.y 4/4] 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 | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/platform/x86/amd/pmc/mp1_stb.c b/drivers/platform/x86/amd/pmc/mp1_stb.c
index 0eeec64df259d..7af8ec7d76531 100644
--- a/drivers/platform/x86/amd/pmc/mp1_stb.c
+++ b/drivers/platform/x86/amd/pmc/mp1_stb.c
@@ -281,7 +281,9 @@ 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;
@@ -293,8 +295,14 @@ int amd_pmc_s2d_init(struct amd_pmc_dev *dev)
 		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);
 	if (!stb_phys_addr) {
-- 
2.53.0