@@ -12,3 +12,11 @@ config MHI_BUS
communication protocol used by the host processors to control
and communicate with modem devices over a high speed peripheral
bus or shared memory.
+
+config MHI_BUS_DEBUG
+ bool "Debugfs support for the MHI bus"
+ depends on MHI_BUS && DEBUG_FS
+ help
+ Enable debugfs support for use with the MHI transport. Allows
+ reading and/or modifying some values within the MHI controller
+ for debug and test purposes.
@@ -1,3 +1,4 @@
obj-$(CONFIG_MHI_BUS) := mhi.o
mhi-y := init.o main.o pm.o boot.o
+mhi-$(CONFIG_MHI_BUS_DEBUG) += debugfs.o
new file mode 100644
@@ -0,0 +1,410 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2020, The Linux Foundation. All rights reserved.
+ *
+ */
+
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/mhi.h>
+#include <linux/module.h>
+#include "internal.h"
+
+static int mhi_debugfs_states_show(struct seq_file *m, void *d)
+{
+ struct mhi_controller *mhi_cntrl = m->private;
+
+ /* states */
+ seq_printf(m, "PM state: %s Device: %s MHI state: %s EE: %s wake: %s\n",
+ to_mhi_pm_state_str(mhi_cntrl->pm_state),
+ mhi_is_active(mhi_cntrl) ? "Active" : "Inactive",
+ TO_MHI_STATE_STR(mhi_cntrl->dev_state),
+ TO_MHI_EXEC_STR(mhi_cntrl->ee),
+ mhi_cntrl->wake_set ? "true" : "false");
+
+ /* counters */
+ seq_printf(m, "M0: %u M2: %u M3: %u", mhi_cntrl->M0, mhi_cntrl->M2,
+ mhi_cntrl->M3);
+
+ seq_printf(m, " device wake: %u pending packets: %u\n",
+ atomic_read(&mhi_cntrl->dev_wake),
+ atomic_read(&mhi_cntrl->pending_pkts));
+
+ return 0;
+}
+
+static int mhi_debugfs_events_show(struct seq_file *m, void *d)
+{
+ struct mhi_controller *mhi_cntrl = m->private;
+ struct mhi_event *mhi_event;
+ struct mhi_event_ctxt *er_ctxt;
+ int i;
+
+ if (!mhi_is_active(mhi_cntrl)) {
+ seq_puts(m, "Device not ready\n");
+ return -ENODEV;
+ }
+
+ er_ctxt = mhi_cntrl->mhi_ctxt->er_ctxt;
+ mhi_event = mhi_cntrl->mhi_event;
+ for (i = 0; i < mhi_cntrl->total_ev_rings;
+ i++, er_ctxt++, mhi_event++) {
+ struct mhi_ring *ring = &mhi_event->ring;
+
+ if (mhi_event->offload_ev) {
+ seq_printf(m, "Index: %d is an offload event ring\n",
+ i);
+ continue;
+ }
+
+ seq_printf(m, "Index: %d intmod count: %lu time: %lu",
+ i, (er_ctxt->intmod & EV_CTX_INTMODC_MASK) >>
+ EV_CTX_INTMODC_SHIFT,
+ (er_ctxt->intmod & EV_CTX_INTMODT_MASK) >>
+ EV_CTX_INTMODT_SHIFT);
+
+ seq_printf(m, " base: 0x%0llx len: 0x%llx", er_ctxt->rbase,
+ er_ctxt->rlen);
+
+ seq_printf(m, " rp: 0x%llx wp: 0x%llx", er_ctxt->rp,
+ er_ctxt->wp);
+
+ seq_printf(m, " local rp: 0x%llx db: 0x%llx\n", (u64)ring->rp,
+ mhi_event->db_cfg.db_val);
+ }
+
+ return 0;
+}
+
+static int mhi_debugfs_channels_show(struct seq_file *m, void *d)
+{
+ struct mhi_controller *mhi_cntrl = m->private;
+ struct mhi_chan *mhi_chan;
+ struct mhi_chan_ctxt *chan_ctxt;
+ int i;
+
+ if (!mhi_is_active(mhi_cntrl)) {
+ seq_puts(m, "Device not ready\n");
+ return -ENODEV;
+ }
+
+ mhi_chan = mhi_cntrl->mhi_chan;
+ chan_ctxt = mhi_cntrl->mhi_ctxt->chan_ctxt;
+ for (i = 0; i < mhi_cntrl->max_chan; i++, chan_ctxt++, mhi_chan++) {
+ struct mhi_ring *ring = &mhi_chan->tre_ring;
+
+ if (mhi_chan->offload_ch) {
+ seq_printf(m, "%s(%u) is an offload channel\n",
+ mhi_chan->name, mhi_chan->chan);
+ continue;
+ }
+
+ if (!mhi_chan->mhi_dev)
+ continue;
+
+ seq_printf(m,
+ "%s(%u) state: 0x%lx brstmode: 0x%lx pollcfg: 0x%lx",
+ mhi_chan->name, mhi_chan->chan, (chan_ctxt->chcfg &
+ CHAN_CTX_CHSTATE_MASK) >> CHAN_CTX_CHSTATE_SHIFT,
+ (chan_ctxt->chcfg & CHAN_CTX_BRSTMODE_MASK) >>
+ CHAN_CTX_BRSTMODE_SHIFT, (chan_ctxt->chcfg &
+ CHAN_CTX_POLLCFG_MASK) >> CHAN_CTX_POLLCFG_SHIFT);
+
+ seq_printf(m, " type: 0x%x event ring: %u", chan_ctxt->chtype,
+ chan_ctxt->erindex);
+
+ seq_printf(m, " base: 0x%llx len: 0x%llx wp: 0x%llx",
+ chan_ctxt->rbase, chan_ctxt->rlen, chan_ctxt->wp);
+
+ seq_printf(m, " local rp: 0x%llx local wp: 0x%llx db: 0x%llx\n",
+ (u64)ring->rp, (u64)ring->wp,
+ mhi_chan->db_cfg.db_val);
+ }
+
+ return 0;
+}
+
+static int mhi_device_info_show(struct device *dev, void *data)
+{
+ struct mhi_device *mhi_dev;
+
+ if (dev->bus != &mhi_bus_type)
+ return 0;
+
+ mhi_dev = to_mhi_device(dev);
+
+ seq_printf((struct seq_file *)data, "%s: type: %s dev_wake: %u",
+ mhi_dev->name, mhi_dev->dev_type ? "Controller" : "Transfer",
+ mhi_dev->dev_wake);
+
+ /* for transfer device types only */
+ if (mhi_dev->dev_type == MHI_DEVICE_XFER)
+ seq_printf((struct seq_file *)data, " channels: %u(UL)/%u(DL)",
+ mhi_dev->ul_chan_id, mhi_dev->dl_chan_id);
+
+ seq_puts((struct seq_file *)data, "\n");
+
+ return 0;
+}
+
+static int mhi_debugfs_devices_show(struct seq_file *m, void *d)
+{
+ struct mhi_controller *mhi_cntrl = m->private;
+
+ if (!mhi_is_active(mhi_cntrl)) {
+ seq_puts(m, "Device not ready\n");
+ return -ENODEV;
+ }
+
+ device_for_each_child(mhi_cntrl->cntrl_dev, m, mhi_device_info_show);
+
+ return 0;
+}
+
+static int mhi_debugfs_regdump_show(struct seq_file *m, void *d)
+{
+ struct mhi_controller *mhi_cntrl = m->private;
+ enum mhi_state state;
+ enum mhi_ee_type ee;
+ int i, ret = -EIO;
+ u32 val;
+ void __iomem *mhi_base = mhi_cntrl->regs;
+ void __iomem *bhi_base = mhi_cntrl->bhi;
+ void __iomem *bhie_base = mhi_cntrl->bhie;
+ void __iomem *wake_db = mhi_cntrl->wake_db;
+ struct {
+ const char *name;
+ int offset;
+ void __iomem *base;
+ } regs[] = {
+ { "MHI_REGLEN", MHIREGLEN, mhi_base},
+ { "MHI_VER", MHIVER, mhi_base},
+ { "MHI_CFG", MHICFG, mhi_base},
+ { "MHI_CTRL", MHICTRL, mhi_base},
+ { "MHI_STATUS", MHISTATUS, mhi_base},
+ { "MHI_WAKE_DB", 0, wake_db},
+ { "BHI_EXECENV", BHI_EXECENV, bhi_base},
+ { "BHI_STATUS", BHI_STATUS, bhi_base},
+ { "BHI_ERRCODE", BHI_ERRCODE, bhi_base},
+ { "BHI_ERRDBG1", BHI_ERRDBG1, bhi_base},
+ { "BHI_ERRDBG2", BHI_ERRDBG2, bhi_base},
+ { "BHI_ERRDBG3", BHI_ERRDBG3, bhi_base},
+ { "BHIE_TXVEC_DB", BHIE_TXVECDB_OFFS, bhie_base},
+ { "BHIE_TXVEC_STATUS", BHIE_TXVECSTATUS_OFFS, bhie_base},
+ { "BHIE_RXVEC_DB", BHIE_RXVECDB_OFFS, bhie_base},
+ { "BHIE_RXVEC_STATUS", BHIE_RXVECSTATUS_OFFS, bhie_base},
+ { NULL },
+ };
+
+ if (!MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state))
+ return ret;
+
+ seq_printf(m, "Host PM state: %s Device state: %s EE: %s\n",
+ to_mhi_pm_state_str(mhi_cntrl->pm_state),
+ TO_MHI_STATE_STR(mhi_cntrl->dev_state),
+ TO_MHI_EXEC_STR(mhi_cntrl->ee));
+
+ state = mhi_get_mhi_state(mhi_cntrl);
+ ee = mhi_get_exec_env(mhi_cntrl);
+ seq_printf(m, "Device EE: %s state: %s\n", TO_MHI_EXEC_STR(ee),
+ TO_MHI_STATE_STR(state));
+
+ for (i = 0; regs[i].name; i++) {
+ if (!regs[i].base)
+ continue;
+ ret = mhi_read_reg(mhi_cntrl, regs[i].base, regs[i].offset,
+ &val);
+ if (ret)
+ continue;
+
+ seq_printf(m, "%s: 0x%x\n", regs[i].name, val);
+ }
+
+ return 0;
+}
+
+static int mhi_debugfs_device_wake_show(struct seq_file *m, void *d)
+{
+ struct mhi_controller *mhi_cntrl = m->private;
+ struct mhi_device *mhi_dev = mhi_cntrl->mhi_dev;
+
+ if (!mhi_is_active(mhi_cntrl)) {
+ seq_puts(m, "Device not ready\n");
+ return -ENODEV;
+ }
+
+ seq_printf(m,
+ "Wake count: %d\n%s\n", mhi_dev->dev_wake,
+ "Usage: echo get/put > device_wake to vote/unvote for M0");
+
+ return 0;
+}
+
+static ssize_t mhi_debugfs_device_wake_write(struct file *file,
+ const char __user *ubuf,
+ size_t count, loff_t *ppos)
+{
+ struct seq_file *m = file->private_data;
+ struct mhi_controller *mhi_cntrl = m->private;
+ struct mhi_device *mhi_dev = mhi_cntrl->mhi_dev;
+ char buf[16];
+ int ret = -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
+ return -EFAULT;
+
+ if (!strncmp(buf, "get", 3)) {
+ ret = mhi_device_get_sync(mhi_dev);
+ } else if (!strncmp(buf, "put", 3)) {
+ mhi_device_put(mhi_dev);
+ ret = 0;
+ }
+
+ return ret ? ret : count;
+}
+
+static int mhi_debugfs_timeout_ms_show(struct seq_file *m, void *d)
+{
+ struct mhi_controller *mhi_cntrl = m->private;
+
+ seq_printf(m, "%u ms\n", mhi_cntrl->timeout_ms);
+
+ return 0;
+}
+
+static ssize_t mhi_debugfs_timeout_ms_write(struct file *file,
+ const char __user *ubuf,
+ size_t count, loff_t *ppos)
+{
+ struct seq_file *m = file->private_data;
+ struct mhi_controller *mhi_cntrl = m->private;
+ u32 timeout_ms;
+
+ if (kstrtou32_from_user(ubuf, count, 0, &timeout_ms))
+ return -EINVAL;
+
+ mhi_cntrl->timeout_ms = timeout_ms;
+
+ return count;
+}
+
+static int mhi_debugfs_states_open(struct inode *inode, struct file *fp)
+{
+ return single_open(fp, mhi_debugfs_states_show, inode->i_private);
+}
+
+static int mhi_debugfs_events_open(struct inode *inode, struct file *fp)
+{
+ return single_open(fp, mhi_debugfs_events_show, inode->i_private);
+}
+
+static int mhi_debugfs_channels_open(struct inode *inode, struct file *fp)
+{
+ return single_open(fp, mhi_debugfs_channels_show, inode->i_private);
+}
+
+static int mhi_debugfs_devices_open(struct inode *inode, struct file *fp)
+{
+ return single_open(fp, mhi_debugfs_devices_show, inode->i_private);
+}
+
+static int mhi_debugfs_regdump_open(struct inode *inode, struct file *fp)
+{
+ return single_open(fp, mhi_debugfs_regdump_show, inode->i_private);
+}
+
+static int mhi_debugfs_device_wake_open(struct inode *inode, struct file *fp)
+{
+ return single_open(fp, mhi_debugfs_device_wake_show, inode->i_private);
+}
+
+static int mhi_debugfs_timeout_ms_open(struct inode *inode, struct file *fp)
+{
+ return single_open(fp, mhi_debugfs_timeout_ms_show, inode->i_private);
+}
+
+static const struct file_operations debugfs_states_fops = {
+ .open = mhi_debugfs_states_open,
+ .release = single_release,
+ .read = seq_read,
+};
+
+static const struct file_operations debugfs_events_fops = {
+ .open = mhi_debugfs_events_open,
+ .release = single_release,
+ .read = seq_read,
+};
+
+static const struct file_operations debugfs_channels_fops = {
+ .open = mhi_debugfs_channels_open,
+ .release = single_release,
+ .read = seq_read,
+};
+
+static const struct file_operations debugfs_devices_fops = {
+ .open = mhi_debugfs_devices_open,
+ .release = single_release,
+ .read = seq_read,
+};
+
+static const struct file_operations debugfs_regdump_fops = {
+ .open = mhi_debugfs_regdump_open,
+ .release = single_release,
+ .read = seq_read,
+};
+
+static const struct file_operations debugfs_device_wake_fops = {
+ .open = mhi_debugfs_device_wake_open,
+ .write = mhi_debugfs_device_wake_write,
+ .release = single_release,
+ .read = seq_read,
+};
+
+static const struct file_operations debugfs_timeout_ms_fops = {
+ .open = mhi_debugfs_timeout_ms_open,
+ .write = mhi_debugfs_timeout_ms_write,
+ .release = single_release,
+ .read = seq_read,
+};
+
+static struct dentry *mhi_debugfs_root;
+
+void mhi_create_debugfs(struct mhi_controller *mhi_cntrl)
+{
+ mhi_cntrl->debugfs_dentry =
+ debugfs_create_dir(dev_name(mhi_cntrl->cntrl_dev),
+ mhi_debugfs_root);
+
+ debugfs_create_file("states", 0444, mhi_cntrl->debugfs_dentry,
+ mhi_cntrl, &debugfs_states_fops);
+ debugfs_create_file("events", 0444, mhi_cntrl->debugfs_dentry,
+ mhi_cntrl, &debugfs_events_fops);
+ debugfs_create_file("channels", 0444, mhi_cntrl->debugfs_dentry,
+ mhi_cntrl, &debugfs_channels_fops);
+ debugfs_create_file("devices", 0444, mhi_cntrl->debugfs_dentry,
+ mhi_cntrl, &debugfs_devices_fops);
+ debugfs_create_file("regdump", 0444, mhi_cntrl->debugfs_dentry,
+ mhi_cntrl, &debugfs_regdump_fops);
+ debugfs_create_file("device_wake", 0644, mhi_cntrl->debugfs_dentry,
+ mhi_cntrl, &debugfs_device_wake_fops);
+ debugfs_create_file("timeout_ms", 0644, mhi_cntrl->debugfs_dentry,
+ mhi_cntrl, &debugfs_timeout_ms_fops);
+}
+
+void mhi_destroy_debugfs(struct mhi_controller *mhi_cntrl)
+{
+ debugfs_remove_recursive(mhi_cntrl->debugfs_dentry);
+ mhi_cntrl->debugfs_dentry = NULL;
+}
+
+void mhi_debugfs_init(void)
+{
+ mhi_debugfs_root = debugfs_create_dir(mhi_bus_type.name, NULL);
+}
+
+void mhi_debugfs_exit(void)
+{
+ debugfs_remove_recursive(mhi_debugfs_root);
+}
@@ -4,6 +4,7 @@
*
*/
+#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/dma-direction.h>
#include <linux/dma-mapping.h>
@@ -915,6 +916,8 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl,
mhi_cntrl->mhi_dev = mhi_dev;
+ mhi_create_debugfs(mhi_cntrl);
+
return 0;
error_add_dev:
@@ -937,6 +940,8 @@ void mhi_unregister_controller(struct mhi_controller *mhi_cntrl)
struct mhi_chan *mhi_chan = mhi_cntrl->mhi_chan;
unsigned int i;
+ mhi_destroy_debugfs(mhi_cntrl);
+
kfree(mhi_cntrl->mhi_cmd);
kfree(mhi_cntrl->mhi_event);
@@ -1300,11 +1305,13 @@ struct bus_type mhi_bus_type = {
static int __init mhi_init(void)
{
+ mhi_debugfs_init();
return bus_register(&mhi_bus_type);
}
static void __exit mhi_exit(void)
{
+ mhi_debugfs_exit();
bus_unregister(&mhi_bus_type);
}
@@ -570,6 +570,30 @@ struct mhi_chan {
/* Default MHI timeout */
#define MHI_TIMEOUT_MS (1000)
+/* debugfs related functions */
+#ifdef CONFIG_MHI_BUS_DEBUG
+void mhi_create_debugfs(struct mhi_controller *mhi_cntrl);
+void mhi_destroy_debugfs(struct mhi_controller *mhi_cntrl);
+void mhi_debugfs_init(void);
+void mhi_debugfs_exit(void);
+#else
+static inline void mhi_create_debugfs(struct mhi_controller *mhi_cntrl)
+{
+}
+
+static inline void mhi_destroy_debugfs(struct mhi_controller *mhi_cntrl)
+{
+}
+
+static inline void mhi_debugfs_init(void)
+{
+}
+
+static inline void mhi_debugfs_exit(void)
+{
+}
+#endif
+
struct mhi_device *mhi_alloc_device(struct mhi_controller *mhi_cntrl);
int mhi_destroy_device(struct device *dev, void *data);
@@ -291,6 +291,7 @@ struct mhi_controller_config {
* @cntrl_dev: Pointer to the struct device of physical bus acting as the MHI
* controller (required)
* @mhi_dev: MHI device instance for the controller
+ * @debugfs_dentry: MHI controller debugfs directory
* @regs: Base address of MHI MMIO register space (required)
* @bhi: Points to base of MHI BHI register space
* @bhie: Points to base of MHI BHIe register space
@@ -370,6 +371,7 @@ struct mhi_controller_config {
struct mhi_controller {
struct device *cntrl_dev;
struct mhi_device *mhi_dev;
+ struct dentry *debugfs_dentry;
void __iomem *regs;
void __iomem *bhi;
void __iomem *bhie;