@@ -1,4 +1,5 @@
# SPDX-License-Identifier: GPL-2.0-only
acpm-protocol-objs := exynos-acpm.o exynos-acpm-pmic.o
+acpm-protocol-$(CONFIG_DEBUG_FS) += exynos-acpm-debugfs.o
obj-$(CONFIG_EXYNOS_ACPM_PROTOCOL) += acpm-protocol.o
new file mode 100644
@@ -0,0 +1,359 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2020 Samsung Electronics Co., Ltd.
+ * Copyright 2020 Google LLC.
+ * Copyright 2025 Linaro Ltd.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/cleanup.h>
+#include <linux/container_of.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/ktime.h>
+#include <linux/math64.h>
+#include <linux/workqueue.h>
+
+#include "exynos-acpm.h"
+
+#define ACPM_DEBUG_CMD BIT(14)
+
+#define ACPM_PRINT_CONFIG GENMASK(15, 14)
+#define ACPM_PRINT_CMD BIT(13)
+#define ACPM_PRINT_SET_LOGB_GPRIO_LEVEL 1
+#define ACPM_PRINT_GET_LOGB_GPRIO_LEVEL 3
+
+#define ACPM_LOG_LEVEL_MAX 2
+#define ACPM_LOG_POLL_PERIOD_US 500
+
+/* Tick runs at 49.152 MHz, the period below is in picoseconds. */
+#define ACPM_APM_SYSTICK_PERIOD_PS 20345
+
+#define ACPM_DEBUGFS_ROOT "acpm_framework"
+
+enum acpm_debug_commands {
+ ACPM_DEBUG_DISABLE_WATCHDOG,
+ ACPM_DEBUG_ENABLE_WATCHDOG,
+ ACPM_DEBUG_SOFT_LOCKUP,
+ ACPM_DEBUG_HARD_LOCKUP,
+ ACPM_DBUG_EXCEPTION,
+ ACPM_DEBUG_NOTIFY_SHUTDOWN,
+ ACPM_DEBUG_RAMDUMP_ON,
+ ACPM_DEBUG_MAX,
+};
+
+struct acpm_log_buf {
+ struct acpm_queue q;
+ unsigned int qlen;
+ unsigned int mlen;
+ unsigned int rear_index;
+};
+
+struct acpm_log_info {
+ struct workqueue_struct *wq;
+ struct acpm_info *acpm;
+ struct delayed_work work;
+ struct acpm_log_buf normal;
+ struct acpm_log_buf preempt;
+ unsigned int level;
+ unsigned int poll_period;
+};
+
+union acpm_log_entry {
+ u32 raw[4];
+ struct {
+ u32 systicks0 : 24;
+ u32 dummy : 2;
+ u32 is_err : 1;
+ u32 is_raw : 1;
+ u32 plugin_id : 4;
+ u32 systicks24;
+ u32 msg : 24;
+ u32 systicks56 : 8;
+ u32 data;
+ } __packed;
+};
+
+static struct dentry *rootdir;
+
+static DEFINE_MUTEX(acpm_log_level_mutex);
+
+static void acpm_log_print_entry(struct acpm_info *acpm,
+ const union acpm_log_entry *log_entry)
+{
+ u64 systicks, time, msg;
+
+ if (log_entry->is_err)
+ return;
+
+ if (log_entry->is_raw) {
+ dev_info(acpm->dev, "[ACPM_FW raw] : id:%u, %x, %x, %x\n",
+ log_entry->plugin_id, log_entry->raw[1],
+ log_entry->raw[2], log_entry->raw[3]);
+ } else {
+ systicks = ((u64)(log_entry->systicks56) << 56) +
+ ((u64)(log_entry->systicks24) << 24) +
+ log_entry->systicks0;
+
+ /* report time in ns */
+ time = mul_u64_u32_div(systicks, ACPM_APM_SYSTICK_PERIOD_PS,
+ 1000);
+
+ msg = readl(acpm->sram_base + log_entry->msg);
+
+ dev_info(acpm->dev, "[ACPM_FW] : %llu id:%u, %s, %x\n", time,
+ log_entry->plugin_id, (char *)&msg, log_entry->data);
+ }
+}
+
+static void acpm_log_print_entries(struct acpm_info *acpm,
+ struct acpm_log_buf *lbuf)
+{
+ union acpm_log_entry log_entry = {0};
+ u32 front, rear;
+
+ front = readl(lbuf->q.front);
+ rear = lbuf->rear_index;
+
+ while (rear != front) {
+ __ioread32_copy(&log_entry, lbuf->q.base + lbuf->mlen * rear,
+ sizeof(log_entry) / 4);
+
+ acpm_log_print_entry(acpm, &log_entry);
+
+ if (lbuf->qlen == rear + 1)
+ rear = 0;
+ else
+ rear++;
+
+ lbuf->rear_index = rear;
+ front = readl(lbuf->q.front);
+ }
+}
+
+static void acpm_log_print(struct acpm_info *acpm)
+{
+ struct acpm_log_info *acpm_log = acpm->log;
+
+ guard(mutex)(&acpm_log_level_mutex);
+
+ if (acpm_log->level == 0)
+ return;
+
+ if (acpm_log->level == ACPM_LOG_LEVEL_MAX)
+ acpm_log_print_entries(acpm, &acpm_log->preempt);
+
+ acpm_log_print_entries(acpm, &acpm_log->normal);
+}
+
+static void acpm_work_fn(struct work_struct *work)
+{
+ struct acpm_log_info *acpm_log =
+ container_of(work, struct acpm_log_info, work.work);
+ struct acpm_info *acpm = acpm_log->acpm;
+
+ acpm_log_print(acpm);
+
+ queue_delayed_work(acpm_log->wq, &acpm_log->work,
+ msecs_to_jiffies(acpm_log->poll_period));
+}
+
+static int acpm_log_level_get(void *data, u64 *val)
+{
+ struct acpm_info *acpm = data;
+
+ *val = acpm->log->level;
+
+ return 0;
+}
+
+static int acpm_log_level_set(void *data, u64 val)
+{
+ struct acpm_info *acpm = data;
+ struct acpm_log_info *acpm_log = acpm->log;
+
+ if (val > ACPM_LOG_LEVEL_MAX) {
+ dev_err(acpm->dev, "Log level %llu out of range [0:%u]!\n",
+ val, ACPM_LOG_LEVEL_MAX);
+ return -EINVAL;
+ }
+
+ scoped_guard(mutex, &acpm_log_level_mutex)
+ acpm_log->level = val;
+
+ if (acpm_log->level == 0)
+ cancel_delayed_work_sync(&acpm_log->work);
+ else
+ queue_delayed_work(acpm_log->wq, &acpm_log->work,
+ msecs_to_jiffies(acpm_log->poll_period));
+ return 0;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(acpm_log_level_fops, acpm_log_level_get,
+ acpm_log_level_set, "0%llu\n");
+
+/**
+ * acpm_logb_gprio_level_get() - get ACPM Log Buffer Group Priority logging
+ * level.
+ * @data: pointer to the driver data.
+ * @val: pointer where the ACPM Log Buffer Group Priority logging level
+ * will be saved.
+ *
+ * The 64 bit hex value encodes the plugin ID log level request on 4 bits,
+ * supporting a maximum of 16 plugin IDs. Plugin ID 0 is described by
+ * GENMASK(3, 0), followed by the other plugin IDs in ascending order, up to
+ * plugin ID 15 which is described by GENMASK(63, 60).
+ * Value 0xf is log error level, and 0x0 is log debug level.
+ */
+static int acpm_logb_gprio_level_get(void *data, u64 *val)
+{
+ struct acpm_info *acpm = data;
+ struct acpm_xfer xfer;
+ u32 cmd[4] = {0};
+ int ret;
+
+ cmd[0] = ACPM_PRINT_CMD |
+ FIELD_PREP(ACPM_PRINT_CONFIG, ACPM_PRINT_GET_LOGB_GPRIO_LEVEL);
+
+ xfer.txd = cmd;
+ xfer.txlen = sizeof(cmd);
+ xfer.rxd = cmd;
+ xfer.rxlen = sizeof(cmd);
+ xfer.acpm_chan_id = acpm->mbox_dbg_chan;
+
+ ret = acpm_do_xfer(&acpm->handle, &xfer);
+ if (!ret)
+ *val = (((u64)xfer.rxd[2]) << 32) | xfer.rxd[1];
+
+ return ret;
+}
+
+/**
+ * acpm_logb_gprio_level_set() - set ACPM Log Buffer Group Priority logging
+ * level.
+ * @data: pointer to the driver data.
+ * @val: 64 bit hex value to set.
+ * The 64 bit hex value encodes the plugin ID log level request on 4 bits,
+ * supporting a maximum of 16 plugin IDs. Plugin ID 0 is described by
+ * GENMASK(3, 0), followed by the other plugin IDs in ascending order, up to
+ * plugin ID 15 which is described by GENMASK(63, 60).
+ * Value 0xf is log error level, and 0x0 is log debug level.
+ */
+static int acpm_logb_gprio_level_set(void *data, u64 val)
+{
+ struct acpm_info *acpm = data;
+ struct acpm_xfer xfer = {0};
+ u32 cmd[4] = {0};
+
+ cmd[0] = ACPM_PRINT_CMD |
+ FIELD_PREP(ACPM_PRINT_CONFIG, ACPM_PRINT_SET_LOGB_GPRIO_LEVEL);
+ cmd[1] = val;
+ cmd[2] = val >> 32;
+
+ xfer.txd = cmd;
+ xfer.txlen = sizeof(cmd);
+ xfer.acpm_chan_id = acpm->mbox_dbg_chan;
+
+ return acpm_do_xfer(&acpm->handle, &xfer);
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(acpm_logb_gprio_level_fops, acpm_logb_gprio_level_get,
+ acpm_logb_gprio_level_set, "0x%016llx\n");
+
+static int acpm_debug_cmd_set(void *data, u64 val)
+{
+ struct acpm_info *acpm = data;
+ struct acpm_xfer xfer = {0};
+ u32 cmd[4] = {0};
+
+ if (val >= ACPM_DEBUG_MAX) {
+ dev_err(acpm->dev, "sub-cmd:%llu out of range!\n", val);
+ return 0;
+ }
+
+ cmd[0] = val | ACPM_DEBUG_CMD;
+
+ xfer.txd = cmd;
+ xfer.txlen = sizeof(cmd);
+ xfer.acpm_chan_id = acpm->mbox_dbg_chan;
+
+ return acpm_do_xfer(&acpm->handle, &xfer);
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(acpm_debug_cmd_fops, NULL, acpm_debug_cmd_set,
+ "0x%016llx\n");
+
+static void acpm_debugfs_init(struct acpm_info *acpm)
+{
+ rootdir = debugfs_create_dir(ACPM_DEBUGFS_ROOT, NULL);
+
+ debugfs_create_file("log_level", 0644, rootdir, acpm,
+ &acpm_log_level_fops);
+ debugfs_create_file("logb_gprio_level", 0644, rootdir, acpm,
+ &acpm_logb_gprio_level_fops);
+ debugfs_create_file("acpm_debug_cmd", 0644, rootdir, acpm,
+ &acpm_debug_cmd_fops);
+}
+
+/**
+ * acpm_debug_get_params() - get debug parameters of the normal and preempt
+ * queues.
+ * @acpm: pointer to the driver data.
+ */
+static void acpm_debug_get_params(struct acpm_info *acpm)
+{
+ struct acpm_shmem __iomem *shmem = acpm->shmem;
+ void __iomem *base = acpm->sram_base;
+ struct acpm_log_info *acpm_log = acpm->log;
+ struct acpm_log_buf *lbuf;
+
+ lbuf = &acpm_log->normal;
+ lbuf->q.base = base + readl(&shmem->log_base);
+ lbuf->q.rear = base + readl(&shmem->log_rear);
+ lbuf->q.front = base + readl(&shmem->log_front);
+ lbuf->qlen = readl(&shmem->log_qlen);
+ lbuf->mlen = readl(&shmem->log_mlen);
+
+ lbuf = &acpm_log->preempt;
+ lbuf->q.base = base + readl(&shmem->preempt_log_base);
+ lbuf->q.rear = base + readl(&shmem->preempt_log_rear);
+ lbuf->q.front = base + readl(&shmem->preempt_log_front);
+ lbuf->qlen = readl(&shmem->preempt_log_qlen);
+ lbuf->mlen = acpm_log->normal.mlen;
+}
+
+/**
+ * acpm_debugfs_register() - register ACPM debug capabilities via debugfs.
+ * @acpm: pointer to the driver data.
+ */
+int acpm_debugfs_register(struct acpm_info *acpm)
+{
+ struct acpm_log_info *acpm_log;
+
+ acpm_log = devm_kzalloc(acpm->dev, sizeof(*acpm_log), GFP_KERNEL);
+ if (!acpm_log)
+ return -ENOMEM;
+
+ acpm->log = acpm_log;
+ acpm_log->acpm = acpm;
+
+ acpm_log->wq = alloc_workqueue("exynos-acpm-log-wq", 0, 0);
+ if (!acpm_log->wq)
+ return -ENOMEM;
+
+ INIT_DELAYED_WORK(&acpm_log->work, acpm_work_fn);
+ acpm_log->poll_period = ACPM_LOG_POLL_PERIOD_US;
+
+ acpm_debug_get_params(acpm);
+
+ acpm_debugfs_init(acpm);
+
+ return 0;
+}
+
+void acpm_debugfs_remove(void)
+{
+ debugfs_remove_recursive(rootdir);
+}
@@ -36,6 +36,7 @@
#define ACPM_TX_TIMEOUT_US 500000
#define ACPM_GS101_INITDATA_BASE 0xa000
+#define ACPM_GS101_MBOX_DBG_CHAN 4
/**
* struct acpm_chan_shmem - descriptor of a shared memory channel.
@@ -130,9 +131,11 @@ struct acpm_chan {
/**
* struct acpm_match_data - of_device_id data.
* @initdata_base: offset in SRAM where the channels configuration resides.
+ * @mbox_dbg_chan: mailbox channel number used for ACPM debug.
*/
struct acpm_match_data {
loff_t initdata_base;
+ unsigned int mbox_dbg_chan;
};
#define client_to_acpm_chan(c) container_of(c, struct acpm_chan, cl)
@@ -577,12 +580,17 @@ static int acpm_probe(struct platform_device *pdev)
"Failed to get match data.\n");
acpm->shmem = acpm->sram_base + match_data->initdata_base;
+ acpm->mbox_dbg_chan = match_data->mbox_dbg_chan;
acpm->dev = dev;
ret = acpm_channels_init(acpm);
if (ret)
return ret;
+ ret = acpm_debugfs_register(acpm);
+ if (ret)
+ return ret;
+
acpm_setup_ops(acpm);
platform_set_drvdata(pdev, acpm);
@@ -590,6 +598,11 @@ static int acpm_probe(struct platform_device *pdev)
return 0;
}
+static void acpm_remove(struct platform_device *pdev)
+{
+ acpm_debugfs_remove();
+}
+
/**
* acpm_handle_put() - release the handle acquired by acpm_get_by_phandle.
* @handle: Handle acquired by acpm_get_by_phandle.
@@ -698,6 +711,7 @@ const struct acpm_handle *devm_acpm_get_by_phandle(struct device *dev,
static const struct acpm_match_data acpm_gs101 = {
.initdata_base = ACPM_GS101_INITDATA_BASE,
+ .mbox_dbg_chan = ACPM_GS101_MBOX_DBG_CHAN,
};
static const struct of_device_id acpm_match[] = {
@@ -711,6 +725,7 @@ MODULE_DEVICE_TABLE(of, acpm_match);
static struct platform_driver acpm_driver = {
.probe = acpm_probe,
+ .remove = acpm_remove,
.driver = {
.name = "exynos-acpm-protocol",
.of_match_table = acpm_match,
@@ -19,12 +19,36 @@
* @chans: offset to array of struct acpm_chan_shmem.
* @reserved1: unused fields.
* @num_chans: number of channels.
+ * @reserved2: unused fields.
+ * @log_rear: rear pointer of APM log queue.
+ * @log_front: front pointer of APM log queue.
+ * @log_base: base address of APM log queue.
+ * @log_mlen: log message length.
+ * @log_qlen: log queue length.
+ * @reserved3: unused fields.
+ * @preempt_log_rear: rear pointer of APM preempt log queue.
+ * @preempt_log_front: front pointer of APM preempt log queue.
+ * @preempt_log_base: base address of APM preempt log queue.
+ * @preempt_log_qlen: preempt log queue length.
+ * @reserved4: unused fields.
*/
struct acpm_shmem {
u32 reserved[2];
u32 chans;
u32 reserved1[3];
u32 num_chans;
+ u32 reserved2[6];
+ u32 log_rear;
+ u32 log_front;
+ u32 log_base;
+ u32 log_mlen;
+ u32 log_qlen;
+ u32 reserved3[24];
+ u32 preempt_log_rear;
+ u32 preempt_log_front;
+ u32 preempt_log_base;
+ u32 preempt_log_qlen;
+ u32 reserved4[64];
};
/**
@@ -41,23 +65,36 @@ struct acpm_queue {
struct device;
struct acpm_chan;
+struct acpm_log_info;
/**
* struct acpm_info - driver's private data.
* @shmem: pointer to the SRAM configuration data.
* @sram_base: base address of SRAM.
+ * @log: pointer to the ACPM logging info.
* @chans: pointer to the ACPM channel parameters retrieved from SRAM.
* @dev: pointer to the exynos-acpm device.
* @handle: instance of acpm_handle to send to clients.
+ * @mbox_dbg_chan: mailbox debug channel.
* @num_chans: number of channels available for this controller.
*/
struct acpm_info {
struct acpm_shmem __iomem *shmem;
void __iomem *sram_base;
+ struct acpm_log_info *log;
struct acpm_chan *chans;
struct device *dev;
struct acpm_handle handle;
+ unsigned int mbox_dbg_chan;
u32 num_chans;
};
+#ifdef CONFIG_DEBUG_FS
+int acpm_debugfs_register(struct acpm_info *acpm);
+void acpm_debugfs_remove(void);
+#else
+static inline int acpm_debugfs_register(struct acpm_info *acpm) {}
+static inline void acpm_debugfs_remove(void) {}
+#endif
+
#endif /* __EXYNOS_ACPM_H__ */
The ACPM firmware saves debug information to SRAM. Add debugfs entries in order to expose the ACPM logs. acpm_framework/logb_gprio_level controls the ACPM print verbosity to the SRAM log buffer. It encodes a 64 bit value, 4 bits for each of the 16 Plugin IDs, with verbosity levels from 0xf (log error) to 0x0 (log debug). echo 0xffffffffffffff1f > /sys/kernel/debug/acpm_framework/logb_gprio_level Will allow only LOG_ERR prints for all Plugin IDs but Plugin ID 1, which will issue prints for any log levels greater or equal to 1. On the ACPM firmware side, logb_gprio_level has a default value of zero, all logs enabled for all Plugin IDs. acpm_framework/log_level has a maximum value of 2 and controls which SRAM log buffers are printed. Finally, acpm_framework/acpm_debug_cmd provides a way to issue ACPM DEBUG commands to the firmware. Add ACPM debugfs support with the above capabilities. Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> --- drivers/firmware/samsung/Makefile | 1 + drivers/firmware/samsung/exynos-acpm-debugfs.c | 359 +++++++++++++++++++++++++ drivers/firmware/samsung/exynos-acpm.c | 15 ++ drivers/firmware/samsung/exynos-acpm.h | 37 +++ 4 files changed, 412 insertions(+)