From: Sarah Walker <sarah.walker@xxxxxxxxxx>
Firmware trace is exposed at /sys/debug/dri/<dev_nr>/pvr_fw/trace_0.
Trace is enabled via the group mask at
/sys/debug/dri/<dev_nr>/pvr_params/fw_trace_mask.
Changes since v8:
- Corrected license identifiers
Changes since v3:
- Use drm_dev_{enter,exit}
Co-developed-by: Matt Coster <matt.coster@xxxxxxxxxx>
Signed-off-by: Matt Coster <matt.coster@xxxxxxxxxx>
Signed-off-by: Sarah Walker <sarah.walker@xxxxxxxxxx>
Signed-off-by: Donald Robson <donald.robson@xxxxxxxxxx>
---
drivers/gpu/drm/imagination/Makefile | 4 +
drivers/gpu/drm/imagination/pvr_debugfs.c | 53 +++
drivers/gpu/drm/imagination/pvr_debugfs.h | 29 ++
drivers/gpu/drm/imagination/pvr_device.c | 9 +
drivers/gpu/drm/imagination/pvr_device.h | 10 +
drivers/gpu/drm/imagination/pvr_drv.c | 4 +
drivers/gpu/drm/imagination/pvr_fw_trace.c | 395 +++++++++++++++++++++
drivers/gpu/drm/imagination/pvr_params.c | 147 ++++++++
drivers/gpu/drm/imagination/pvr_params.h | 72 ++++
9 files changed, 723 insertions(+)
create mode 100644 drivers/gpu/drm/imagination/pvr_debugfs.c
create mode 100644 drivers/gpu/drm/imagination/pvr_debugfs.h
create mode 100644 drivers/gpu/drm/imagination/pvr_params.c
create mode 100644 drivers/gpu/drm/imagination/pvr_params.h
diff --git a/drivers/gpu/drm/imagination/Makefile b/drivers/gpu/drm/imagination/Makefile
index 7e3515c99caa..ec6db8e9b403 100644
--- a/drivers/gpu/drm/imagination/Makefile
+++ b/drivers/gpu/drm/imagination/Makefile
@@ -20,6 +20,7 @@ powervr-y := \
pvr_hwrt.o \
pvr_job.o \
pvr_mmu.o \
+ pvr_params.o \
pvr_power.o \
pvr_queue.o \
pvr_stream.o \
@@ -28,4 +29,7 @@ powervr-y := \
pvr_vm.o \
pvr_vm_mips.o
+powervr-$(CONFIG_DEBUG_FS) += \
+ pvr_debugfs.o
+
obj-$(CONFIG_DRM_POWERVR) += powervr.o
diff --git a/drivers/gpu/drm/imagination/pvr_debugfs.c b/drivers/gpu/drm/imagination/pvr_debugfs.c
new file mode 100644
index 000000000000..6b77c9b4bde8
--- /dev/null
+++ b/drivers/gpu/drm/imagination/pvr_debugfs.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+/* Copyright (c) 2023 Imagination Technologies Ltd. */
+
+#include "pvr_debugfs.h"
+
+#include "pvr_device.h"
+#include "pvr_fw_trace.h"
+#include "pvr_params.h"
+
+#include <linux/dcache.h>
+#include <linux/debugfs.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+
+#include <drm/drm_device.h>
+#include <drm/drm_file.h>
+#include <drm/drm_print.h>
+
+static const struct pvr_debugfs_entry pvr_debugfs_entries[] = {
+ {"pvr_params", pvr_params_debugfs_init},
+ {"pvr_fw", pvr_fw_trace_debugfs_init},
+};
+
+void
+pvr_debugfs_init(struct drm_minor *minor)
+{
+ struct drm_device *drm_dev = minor->dev;
+ struct pvr_device *pvr_dev = to_pvr_device(drm_dev);
+ struct dentry *root = minor->debugfs_root;
+ size_t i;
+
+ for (i = 0; i < ARRAY_SIZE(pvr_debugfs_entries); ++i) {
+ const struct pvr_debugfs_entry *entry = &pvr_debugfs_entries[i];
+ struct dentry *dir;
+
+ dir = debugfs_create_dir(entry->name, root);
+ if (IS_ERR(dir)) {
+ drm_warn(drm_dev,
+ "failed to create debugfs dir '%s' (err=%d)",
+ entry->name, (int)PTR_ERR(dir));
+ continue;
+ }
+
+ entry->init(pvr_dev, dir);
+ }
+}
+
+/*
+ * Since all entries are created under &drm_minor->debugfs_root, there's no
+ * need for a pvr_debugfs_fini() as DRM will clean up everything under its root
+ * automatically.
+ */
diff --git a/drivers/gpu/drm/imagination/pvr_debugfs.h b/drivers/gpu/drm/imagination/pvr_debugfs.h
new file mode 100644
index 000000000000..ebacbd13b84a
--- /dev/null
+++ b/drivers/gpu/drm/imagination/pvr_debugfs.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0-only OR MIT */
+/* Copyright (c) 2023 Imagination Technologies Ltd. */
+
+#ifndef PVR_DEBUGFS_H
+#define PVR_DEBUGFS_H
+
+/* Forward declaration from <drm/drm_drv.h>. */
+struct drm_minor;
+
+#if defined(CONFIG_DEBUG_FS)
+/* Forward declaration from "pvr_device.h". */
+struct pvr_device;
+
+/* Forward declaration from <linux/dcache.h>. */
+struct dentry;
+
+struct pvr_debugfs_entry {
+ const char *name;
+ void (*init)(struct pvr_device *pvr_dev, struct dentry *dir);
+};
+
+void pvr_debugfs_init(struct drm_minor *minor);
+#else /* defined(CONFIG_DEBUG_FS) */
+#include <linux/compiler_attributes.h>
+
+static __always_inline void pvr_debugfs_init(struct drm_minor *minor) {}
+#endif /* defined(CONFIG_DEBUG_FS) */
+
+#endif /* PVR_DEBUGFS_H */
diff --git a/drivers/gpu/drm/imagination/pvr_device.c b/drivers/gpu/drm/imagination/pvr_device.c
index 199f812d1ee7..8499becf4fbb 100644
--- a/drivers/gpu/drm/imagination/pvr_device.c
+++ b/drivers/gpu/drm/imagination/pvr_device.c
@@ -5,6 +5,7 @@
#include "pvr_device_info.h"
#include "pvr_fw.h"
+#include "pvr_params.h"
#include "pvr_power.h"
#include "pvr_queue.h"
#include "pvr_rogue_cr_defs.h"
@@ -495,6 +496,14 @@ pvr_device_init(struct pvr_device *pvr_dev)
struct device *dev = drm_dev->dev;
int err;
+ /*
+ * Setup device parameters. We do this first in case other steps
+ * depend on them.
+ */
+ err = pvr_device_params_init(&pvr_dev->params);
+ if (err)
+ return err;
+
/* Enable and initialize clocks required for the device to operate. */
err = pvr_device_clk_init(pvr_dev);
if (err)
diff --git a/drivers/gpu/drm/imagination/pvr_device.h b/drivers/gpu/drm/imagination/pvr_device.h
index b6e9a7e8072e..e07655fc65e8 100644
--- a/drivers/gpu/drm/imagination/pvr_device.h
+++ b/drivers/gpu/drm/imagination/pvr_device.h
@@ -7,6 +7,7 @@
#include "pvr_ccb.h"
#include "pvr_device_info.h"
#include "pvr_fw.h"
+#include "pvr_params.h"
#include "pvr_rogue_fwif_stream.h"
#include "pvr_stream.h"
@@ -148,6 +149,15 @@ struct pvr_device {
/** @fw_dev: Firmware related data. */
struct pvr_fw_device fw_dev;
+ /**
+ * @params: Device-specific parameters.
+ *
+ * The values of these parameters are initialized from the
+ * defaults specified as module parameters. They may be
+ * modified at runtime via debugfs (if enabled).
+ */
+ struct pvr_device_params params;
+
/** @stream_musthave_quirks: Bit array of "must-have" quirks for stream commands. */
u32 stream_musthave_quirks[PVR_STREAM_TYPE_MAX][PVR_STREAM_EXTHDR_TYPE_MAX];
diff --git a/drivers/gpu/drm/imagination/pvr_drv.c b/drivers/gpu/drm/imagination/pvr_drv.c
index a6f1d52aaebb..5c3b2d58d766 100644
--- a/drivers/gpu/drm/imagination/pvr_drv.c
+++ b/drivers/gpu/drm/imagination/pvr_drv.c
@@ -2,6 +2,7 @@
/* Copyright (c) 2023 Imagination Technologies Ltd. */
#include "pvr_context.h"
+#include "pvr_debugfs.h"
#include "pvr_device.h"
#include "pvr_drv.h"
#include "pvr_free_list.h"
@@ -1377,6 +1378,9 @@ static struct drm_driver pvr_drm_driver = {
.ioctls = pvr_drm_driver_ioctls,
.num_ioctls = ARRAY_SIZE(pvr_drm_driver_ioctls),
.fops = &pvr_drm_driver_fops,
+#if defined(CONFIG_DEBUG_FS)
+ .debugfs_init = pvr_debugfs_init,
+#endif
.name = PVR_DRIVER_NAME,
.desc = PVR_DRIVER_DESC,
diff --git a/drivers/gpu/drm/imagination/pvr_fw_trace.c b/drivers/gpu/drm/imagination/pvr_fw_trace.c
index 0a8340369f1a..87a42fb6ace6 100644
--- a/drivers/gpu/drm/imagination/pvr_fw_trace.c
+++ b/drivers/gpu/drm/imagination/pvr_fw_trace.c
@@ -4,8 +4,10 @@
#include "pvr_device.h"
#include "pvr_gem.h"
#include "pvr_rogue_fwif.h"
+#include "pvr_rogue_fwif_sf.h"
#include "pvr_fw_trace.h"
+#include <drm/drm_drv.h>
#include <drm/drm_file.h>
#include <linux/build_bug.h>
@@ -118,3 +120,396 @@ void pvr_fw_trace_fini(struct pvr_device *pvr_dev)
}
pvr_fw_object_unmap_and_destroy(fw_trace->tracebuf_ctrl_obj);
}
+
+/**
+ * update_logtype() - Send KCCB command to trigger FW to update logtype
+ * @pvr_dev: Target PowerVR device
+ * @group_mask: New log group mask.
+ *
+ * Returns:
+ * * 0 on success,
+ * * Any error returned by pvr_kccb_send_cmd(), or
+ * * -%EIO if the device is lost.
+ */
+static int
+update_logtype(struct pvr_device *pvr_dev, u32 group_mask)
+{
+ struct pvr_fw_trace *fw_trace = &pvr_dev->fw_dev.fw_trace;
+ struct rogue_fwif_kccb_cmd cmd;
+ int idx;
+ int err;
+
+ if (group_mask)
+ fw_trace->tracebuf_ctrl->log_type = ROGUE_FWIF_LOG_TYPE_TRACE | group_mask;
+ else
+ fw_trace->tracebuf_ctrl->log_type = ROGUE_FWIF_LOG_TYPE_NONE;
+
+ fw_trace->group_mask = group_mask;
+
+ down_read(&pvr_dev->reset_sem);
+ if (!drm_dev_enter(from_pvr_device(pvr_dev), &idx)) {
+ err = -EIO;
+ goto err_up_read;
+ }
+
+ cmd.cmd_type = ROGUE_FWIF_KCCB_CMD_LOGTYPE_UPDATE;
+ cmd.kccb_flags = 0;
+
+ err = pvr_kccb_send_cmd(pvr_dev, &cmd, NULL);
+
+ drm_dev_exit(idx);
+
+err_up_read:
+ up_read(&pvr_dev->reset_sem);
+
+ return err;
+}
+
+#if defined(CONFIG_DEBUG_FS)
+
+static int fw_trace_group_mask_show(struct seq_file *m, void *data)
+{
+ struct pvr_device *pvr_dev = m->private;
+
+ seq_printf(m, "%08x\n", pvr_dev->fw_dev.fw_trace.group_mask);
+
+ return 0;
+}
+
+static int fw_trace_group_mask_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, fw_trace_group_mask_show, inode->i_private);
+}
+
+static ssize_t fw_trace_group_mask_write(struct file *file, const char __user *ubuf, size_t len,
+ loff_t *offp)
+{
+ struct seq_file *m = file->private_data;
+ struct pvr_device *pvr_dev = m->private;
+ u32 new_group_mask;
+ int err;
+
+ err = kstrtouint_from_user(ubuf, len, 0, &new_group_mask);
+ if (err)
+ return err;
+
+ err = update_logtype(pvr_dev, new_group_mask);
+ if (err)
+ return err;
+
+ pvr_dev->fw_dev.fw_trace.group_mask = new_group_mask;
+
+ return (ssize_t)len;
+}
+
+static const struct file_operations pvr_fw_trace_group_mask_fops = {
+ .owner = THIS_MODULE,
+ .open = fw_trace_group_mask_open,
+ .read = seq_read,
+ .write = fw_trace_group_mask_write,
+ .llseek = default_llseek,
+ .release = single_release,
+};
+
+struct pvr_fw_trace_seq_data {
+ /** @buffer: Pointer to copy of trace data. */
+ u32 *buffer;
+
+ /** @start_offset: Starting offset in trace data, as reported by FW. */
+ u32 start_offset;
+
+ /** @idx: Current index into trace data. */
+ u32 idx;
+
+ /** @assert_buf: Trace assert buffer, as reported by FW. */
+ struct rogue_fwif_file_info_buf assert_buf;
+};
+
+static u32 find_sfid(u32 id)
+{
+ u32 i;
+
+ for (i = 0; i < ARRAY_SIZE(stid_fmts); i++) {
+ if (stid_fmts[i].id == id)
+ return i;
+ }
+
+ return ROGUE_FW_SF_LAST;
+}
+
+static u32 read_fw_trace(struct pvr_fw_trace_seq_data *trace_seq_data, u32 offset)
+{
+ u32 idx;
+
+ idx = trace_seq_data->idx + offset;
+ if (idx >= ROGUE_FW_TRACE_BUF_DEFAULT_SIZE_IN_DWORDS)
+ return 0;
+
+ idx = (idx + trace_seq_data->start_offset) % ROGUE_FW_TRACE_BUF_DEFAULT_SIZE_IN_DWORDS;
+ return trace_seq_data->buffer[idx];
+}
+
+/**
+ * fw_trace_get_next() - Advance trace index to next entry
+ * @trace_seq_data: Trace sequence data.
+ *
+ * Returns:
+ * * %true if trace index is now pointing to a valid entry, or
+ * * %false if trace index is pointing to an invalid entry, or has hit the end
+ * of the trace.
+ */
+static bool fw_trace_get_next(struct pvr_fw_trace_seq_data *trace_seq_data)
+{
+ u32 id, sf_id;
+
+ while (trace_seq_data->idx < ROGUE_FW_TRACE_BUF_DEFAULT_SIZE_IN_DWORDS) {
+ id = read_fw_trace(trace_seq_data, 0);
+ trace_seq_data->idx++;
+ if (!ROGUE_FW_LOG_VALIDID(id))
+ continue;
+ if (id == ROGUE_FW_SF_MAIN_ASSERT_FAILED) {
+ /* Assertion failure marks the end of the trace. */
+ return false;
+ }
+
+ sf_id = find_sfid(id);
+ if (sf_id == ROGUE_FW_SF_FIRST)
+ continue;
+ if (sf_id == ROGUE_FW_SF_LAST) {
+ /*
+ * Could not match with an ID in the SF table, trace is
+ * most likely corrupt from this point.
+ */
+ return false;
+ }
+
+ /* Skip over the timestamp, and any parameters. */
+ trace_seq_data->idx += 2 + ROGUE_FW_SF_PARAMNUM(id);
+
+ /* Ensure index is now pointing to a valid trace entry. */
+ id = read_fw_trace(trace_seq_data, 0);
+ if (!ROGUE_FW_LOG_VALIDID(id))
+ continue;
+
+ return true;
+ };
+
+ /* Hit end of trace data. */
+ return false;
+}
+
+/**
+ * fw_trace_get_first() - Find first valid entry in trace
+ * @trace_seq_data: Trace sequence data.
+ *
+ * Skips over invalid (usually zero) and ROGUE_FW_SF_FIRST entries.
+ *
+ * If the trace has no valid entries, this function will exit with the trace
+ * index pointing to the end of the trace. trace_seq_show() will return an error
+ * in this state.
+ */
+static void fw_trace_get_first(struct pvr_fw_trace_seq_data *trace_seq_data)
+{
+ trace_seq_data->idx = 0;
+
+ while (trace_seq_data->idx < ROGUE_FW_TRACE_BUF_DEFAULT_SIZE_IN_DWORDS) {
+ u32 id = read_fw_trace(trace_seq_data, 0);
+
+ if (ROGUE_FW_LOG_VALIDID(id)) {
+ u32 sf_id = find_sfid(id);
+
+ if (sf_id != ROGUE_FW_SF_FIRST)
+ break;
+ }
+ trace_seq_data->idx++;
+ }
+}
+
+static void *fw_trace_seq_start(struct seq_file *s, loff_t *pos)
+{
+ struct pvr_fw_trace_seq_data *trace_seq_data = s->private;
+ u32 i;
+
+ /* Reset trace index, then advance to *pos. */
+ fw_trace_get_first(trace_seq_data);
+
+ for (i = 0; i < *pos; i++) {
+ if (!fw_trace_get_next(trace_seq_data))
+ return NULL;
+ }
+
+ return (trace_seq_data->idx < ROGUE_FW_TRACE_BUF_DEFAULT_SIZE_IN_DWORDS) ? pos : NULL;
+}
+
+static void *fw_trace_seq_next(struct seq_file *s, void *v, loff_t *pos)
+{
+ struct pvr_fw_trace_seq_data *trace_seq_data = s->private;
+
+ (*pos)++;
+ if (!fw_trace_get_next(trace_seq_data))
+ return NULL;
+
+ return (trace_seq_data->idx < ROGUE_FW_TRACE_BUF_DEFAULT_SIZE_IN_DWORDS) ? pos : NULL;
+}
+
+static void fw_trace_seq_stop(struct seq_file *s, void *v)
+{
+}
+
+static int fw_trace_seq_show(struct seq_file *s, void *v)
+{
+ struct pvr_fw_trace_seq_data *trace_seq_data = s->private;
+ u64 timestamp;
+ u32 id;
+ u32 sf_id;
+
+ if (trace_seq_data->idx >= ROGUE_FW_TRACE_BUF_DEFAULT_SIZE_IN_DWORDS)
+ return -EINVAL;
+
+ id = read_fw_trace(trace_seq_data, 0);
+ /* Index is not pointing at a valid entry. */
+ if (!ROGUE_FW_LOG_VALIDID(id))
+ return -EINVAL;
+
+ sf_id = find_sfid(id);
+ /* Index is not pointing at a valid entry. */
+ if (sf_id == ROGUE_FW_SF_LAST)
+ return -EINVAL;
+
+ timestamp = read_fw_trace(trace_seq_data, 1) |
+ ((u64)read_fw_trace(trace_seq_data, 2) << 32);
+ timestamp = (timestamp & ~ROGUE_FWT_TIMESTAMP_TIME_CLRMSK) >>
+ ROGUE_FWT_TIMESTAMP_TIME_SHIFT;
+
+ seq_printf(s, "[%llu] : ", timestamp);
+ if (id == ROGUE_FW_SF_MAIN_ASSERT_FAILED) {
+ seq_printf(s, "ASSERTION %s failed at %s:%u",
+ trace_seq_data->assert_buf.info,
+ trace_seq_data->assert_buf.path,
+ trace_seq_data->assert_buf.line_num);
+ } else {
+ seq_printf(s, stid_fmts[sf_id].name,
+ read_fw_trace(trace_seq_data, 3),
+ read_fw_trace(trace_seq_data, 4),
+ read_fw_trace(trace_seq_data, 5),
+ read_fw_trace(trace_seq_data, 6),
+ read_fw_trace(trace_seq_data, 7),
+ read_fw_trace(trace_seq_data, 8),
+ read_fw_trace(trace_seq_data, 9),
+ read_fw_trace(trace_seq_data, 10),
+ read_fw_trace(trace_seq_data, 11),
+ read_fw_trace(trace_seq_data, 12),
+ read_fw_trace(trace_seq_data, 13),
+ read_fw_trace(trace_seq_data, 14),
+ read_fw_trace(trace_seq_data, 15),
+ read_fw_trace(trace_seq_data, 16),
+ read_fw_trace(trace_seq_data, 17),
+ read_fw_trace(trace_seq_data, 18),
+ read_fw_trace(trace_seq_data, 19),
+ read_fw_trace(trace_seq_data, 20),
+ read_fw_trace(trace_seq_data, 21),
+ read_fw_trace(trace_seq_data, 22));
+ }
+ seq_puts(s, "\n");
+ return 0;
+}
+
+static const struct seq_operations pvr_fw_trace_seq_ops = {
+ .start = fw_trace_seq_start,
+ .next = fw_trace_seq_next,
+ .stop = fw_trace_seq_stop,
+ .show = fw_trace_seq_show
+};
+
+static int fw_trace_open(struct inode *inode, struct file *file)
+{
+ struct pvr_fw_trace_buffer *trace_buffer = inode->i_private;
+ struct rogue_fwif_tracebuf_space *tracebuf_space =
+ trace_buffer->tracebuf_space;
+ struct pvr_fw_trace_seq_data *trace_seq_data;
+ int err;
+
+ trace_seq_data = kzalloc(sizeof(*trace_seq_data), GFP_KERNEL);
+ if (!trace_seq_data)
+ return -ENOMEM;
+
+ trace_seq_data->buffer = kcalloc(ROGUE_FW_TRACE_BUF_DEFAULT_SIZE_IN_DWORDS,
+ sizeof(*trace_seq_data->buffer), GFP_KERNEL);
+ if (!trace_seq_data->buffer) {
+ err = -ENOMEM;
+ goto err_free_data;
+ }
+
+ /*
+ * Take a local copy of the trace buffer, as firmware may still be
+ * writing to it. This will exist as long as this file is open.
+ */
+ memcpy(trace_seq_data->buffer, trace_buffer->buf,
+ ROGUE_FW_TRACE_BUF_DEFAULT_SIZE_IN_DWORDS * sizeof(u32));
+ trace_seq_data->start_offset = READ_ONCE(tracebuf_space->trace_pointer);
+ trace_seq_data->assert_buf = tracebuf_space->assert_buf;
+ fw_trace_get_first(trace_seq_data);
+
+ err = seq_open(file, &pvr_fw_trace_seq_ops);
+ if (err)
+ goto err_free_buffer;
+
+ ((struct seq_file *)file->private_data)->private = trace_seq_data;
+
+ return 0;
+
+err_free_buffer:
+ kfree(trace_seq_data->buffer);
+
+err_free_data:
+ kfree(trace_seq_data);
+
+ return err;
+}
+
+static int fw_trace_release(struct inode *inode, struct file *file)
+{
+ struct pvr_fw_trace_seq_data *trace_seq_data =
+ ((struct seq_file *)file->private_data)->private;
+
+ seq_release(inode, file);
+ kfree(trace_seq_data->buffer);
+ kfree(trace_seq_data);
+
+ return 0;
+}
+
+static const struct file_operations pvr_fw_trace_fops = {
+ .owner = THIS_MODULE,
+ .open = fw_trace_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = fw_trace_release,
+};
+
+void
+pvr_fw_trace_mask_update(struct pvr_device *pvr_dev, u32 old_mask, u32 new_mask)
+{
+ if (old_mask != new_mask)
+ update_logtype(pvr_dev, new_mask);
+}
+
+void
+pvr_fw_trace_debugfs_init(struct pvr_device *pvr_dev, struct dentry *dir)
+{
+ struct pvr_fw_trace *fw_trace = &pvr_dev->fw_dev.fw_trace;
+ u32 thread_nr;
+
+ static_assert(ARRAY_SIZE(fw_trace->buffers) <= 10,
+ "The filename buffer is only large enough for a single-digit thread count");
+
+ for (thread_nr = 0; thread_nr < ARRAY_SIZE(fw_trace->buffers); ++thread_nr) {
+ char filename[8];
+
+ snprintf(filename, ARRAY_SIZE(filename), "trace_%u", thread_nr);
+ debugfs_create_file(filename, 0400, dir,
+ &fw_trace->buffers[thread_nr],
+ &pvr_fw_trace_fops);
+ }
+}
+#endif
diff --git a/drivers/gpu/drm/imagination/pvr_params.c b/drivers/gpu/drm/imagination/pvr_params.c
new file mode 100644
index 000000000000..b91759f362c5
--- /dev/null
+++ b/drivers/gpu/drm/imagination/pvr_params.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+/* Copyright (c) 2023 Imagination Technologies Ltd. */
+
+#include "pvr_params.h"
+
+#include <linux/cache.h>
+#include <linux/moduleparam.h>
+
+static struct pvr_device_params pvr_device_param_defaults __read_mostly = {
+#define X(type_, name_, value_, desc_, ...) .name_ = (value_),
+ PVR_DEVICE_PARAMS
+#undef X
+};
+
+#define PVR_DEVICE_PARAM_NAMED(name_, type_, desc_) \
+ module_param_named(name_, pvr_device_param_defaults.name_, type_, \
+ 0400); \
+ MODULE_PARM_DESC(name_, desc_);
+
+/*
+ * This list of defines must contain every type specified in "pvr_params.h" as
+ * ``PVR_PARAM_TYPE_*_C``.
+ */
+#define PVR_PARAM_TYPE_X32_MODPARAM uint
+
+#define X(type_, name_, value_, desc_, ...) \
+ PVR_DEVICE_PARAM_NAMED(name_, PVR_PARAM_TYPE_##type_##_MODPARAM, desc_);
+PVR_DEVICE_PARAMS
+#undef X
+
+int
+pvr_device_params_init(struct pvr_device_params *params)
+{
+ /*
+ * If heap-allocated parameters are added in the future (e.g.
+ * modparam's charp type), they must be handled specially here (via
+ * kstrdup() in the case of charp). Since that's not necessary yet,
+ * a straight copy will do for now. This change will also require a
+ * pvr_device_params_fini() function to free any heap-allocated copies.
+ */
+
+ *params = pvr_device_param_defaults;
+
+ return 0;
+}
+
+#if defined(CONFIG_DEBUG_FS)
+#include "pvr_device.h"
+
+#include <linux/dcache.h>
+#include <linux/debugfs.h>
+#include <linux/export.h>
+#include <linux/fs.h>
+#include <linux/stddef.h>
+
+/*
+ * This list of defines must contain every type specified in "pvr_params.h" as
+ * ``PVR_PARAM_TYPE_*_C``.
+ */
+#define PVR_PARAM_TYPE_X32_FMT "0x%08llx"
+
+#define X_SET(name_, mode_) X_SET_##mode_(name_)
+#define X_SET_DEF(name_, update_, mode_) X_SET_DEF_##mode_(name_, update_)
+
+#define X_SET_RO(name_) NULL
+#define X_SET_RW(name_) __pvr_device_param_##name_##set
+
+#define X_SET_DEF_RO(name_, update_)
+#define X_SET_DEF_RW(name_, update_) \
+ static int \
+ X_SET_RW(name_)(void *data, u64 val) \
+ { \
+ struct pvr_device *pvr_dev = data; \
+ /* This is not just (update_) to suppress -Waddress. */ \
+ if ((void *)(update_) != NULL) \
+ (update_)(pvr_dev, pvr_dev->params.name_, val); \
+ pvr_dev->params.name_ = val; \
+ return 0; \
+ }
+
+#define X(type_, name_, value_, desc_, mode_, update_) \
+ static int \
+ __pvr_device_param_##name_##_get(void *data, u64 *val) \
+ { \
+ struct pvr_device *pvr_dev = data; \
+ *val = pvr_dev->params.name_; \
+ return 0; \
+ } \
+ X_SET_DEF(name_, update_, mode_) \
+ static int \
+ __pvr_device_param_##name_##_open(struct inode *inode, \
+ struct file *file) \
+ { \
+ __simple_attr_check_format(PVR_PARAM_TYPE_##type_##_FMT, \
+ 0ull); \
+ return simple_attr_open(inode, file, \
+ __pvr_device_param_##name_##_get, \
+ X_SET(name_, mode_), \
+ PVR_PARAM_TYPE_##type_##_FMT); \
+ }
+PVR_DEVICE_PARAMS
+#undef X
+
+#undef X_SET
+#undef X_SET_RO
+#undef X_SET_RW
+#undef X_SET_DEF
+#undef X_SET_DEF_RO
+#undef X_SET_DEF_RW
+
+static struct {
+#define X(type_, name_, value_, desc_, mode_, update_) \
+ const struct file_operations name_;
+ PVR_DEVICE_PARAMS
+#undef X
+} pvr_device_param_debugfs_fops = {
+#define X(type_, name_, value_, desc_, mode_, update_) \
+ .name_ = { \
+ .owner = THIS_MODULE, \
+ .open = __pvr_device_param_##name_##_open, \
+ .release = simple_attr_release, \
+ .read = simple_attr_read, \
+ .write = simple_attr_write, \
+ .llseek = generic_file_llseek, \
+ },
+ PVR_DEVICE_PARAMS
+#undef X
+};
+
+void
+pvr_params_debugfs_init(struct pvr_device *pvr_dev, struct dentry *dir)
+{
+#define X_MODE(mode_) X_MODE_##mode_
+#define X_MODE_RO 0400
+#define X_MODE_RW 0600
+
+#define X(type_, name_, value_, desc_, mode_, update_) \
+ debugfs_create_file(#name_, X_MODE(mode_), dir, pvr_dev, \
+ &pvr_device_param_debugfs_fops.name_);
+ PVR_DEVICE_PARAMS
+#undef X
+
+#undef X_MODE
+#undef X_MODE_RO
+#undef X_MODE_RW
+}
+#endif
diff --git a/drivers/gpu/drm/imagination/pvr_params.h b/drivers/gpu/drm/imagination/pvr_params.h
new file mode 100644
index 000000000000..5807915b456b
--- /dev/null
+++ b/drivers/gpu/drm/imagination/pvr_params.h
@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: GPL-2.0-only OR MIT */
+/* Copyright (c) 2023 Imagination Technologies Ltd. */
+
+#ifndef PVR_PARAMS_H
+#define PVR_PARAMS_H
+
+#include "pvr_rogue_fwif.h"
+
+#include <linux/cache.h>
+#include <linux/compiler_attributes.h>
+
+/*
+ * This is the definitive list of types allowed in the definition of
+ * %PVR_DEVICE_PARAMS.
+ */
+#define PVR_PARAM_TYPE_X32_C u32
+
+/*
+ * This macro defines all device-specific parameters; that is parameters which
+ * are set independently per device.
+ *
+ * The X-macro accepts the following arguments. Arguments marked with [debugfs]
+ * are ignored when debugfs is disabled; values used for these arguments may
+ * safely be gated behind CONFIG_DEBUG_FS.
+ *
+ * @type_: The definitive list of allowed values is PVR_PARAM_TYPE_*_C.
+ * @name_: Name of the parameter. This is used both as the field name in C and
+ * stringified as the parameter name.
+ * @value_: Initial/default value.
+ * @desc_: String literal used as help text to describe the usage of this
+ * parameter.
+ * @mode_: [debugfs] One of {RO,RW}. The access mode of the debugfs entry for
+ * this parameter.
+ * @update_: [debugfs] When debugfs support is enabled, parameters may be
+ * updated at runtime. When this happens, this function will be
+ * called to allow changes to propagate. The signature of this
+ * function is:
+ *
+ * void (*)(struct pvr_device *pvr_dev, T old_val, T new_val)
+ *
+ * Where T is the C type associated with @type_.
+ *
+ * If @mode_ does not allow write access, this function will never be
+ * called. In this case, or if no update callback is required, you
+ * should specify NULL for this argument.
+ */
+#define PVR_DEVICE_PARAMS \
+ X(X32, fw_trace_mask, ROGUE_FWIF_LOG_TYPE_NONE, \
+ "Enable FW trace for the specified groups. Specifying 0 disables " \
+ "all FW tracing.", \
+ RW, pvr_fw_trace_mask_update)
+
+struct pvr_device_params {
+#define X(type_, name_, value_, desc_, ...) \
+ PVR_PARAM_TYPE_##type_##_C name_;
+ PVR_DEVICE_PARAMS
+#undef X
+};
+
+int pvr_device_params_init(struct pvr_device_params *params);
+
+#if defined(CONFIG_DEBUG_FS)
+/* Forward declaration from "pvr_device.h". */
+struct pvr_device;
+
+/* Forward declaration from <linux/dcache.h>. */
+struct dentry;
+
+void pvr_params_debugfs_init(struct pvr_device *pvr_dev, struct dentry *dir);
+#endif /* defined(CONFIG_DEBUG_FS) */
+
+#endif /* PVR_PARAMS_H */
--
2.25.1
