[PATCH 1/3] STM: MIPI System Trace Module char driver
From: philippe.langlais
Date: Thu Mar 17 2011 - 05:40:46 EST
From: Philippe Langlais <philippe.langlais@xxxxxxxxxx>
Signed-off-by: Philippe Langlais <philippe.langlais@xxxxxxxxxx>
---
Documentation/trace/stm-trace.txt | 193 +++++++++
drivers/misc/Kconfig | 1 +
drivers/misc/Kconfig.stm | 114 ++++++
drivers/misc/Makefile | 1 +
drivers/misc/stm.c | 797 +++++++++++++++++++++++++++++++++++++
include/Kbuild | 1 +
include/trace/Kbuild | 1 +
include/trace/stm.h | 223 +++++++++++
8 files changed, 1331 insertions(+), 0 deletions(-)
create mode 100644 Documentation/trace/stm-trace.txt
create mode 100644 drivers/misc/Kconfig.stm
create mode 100644 drivers/misc/stm.c
create mode 100644 include/trace/Kbuild
create mode 100644 include/trace/stm.h
diff --git a/Documentation/trace/stm-trace.txt b/Documentation/trace/stm-trace.txt
new file mode 100644
index 0000000..4d916bc
--- /dev/null
+++ b/Documentation/trace/stm-trace.txt
@@ -0,0 +1,193 @@
+ MIPI System Trace Module driver
+ ===============================
+
+Copyright (C) ST-Ericsson SA 2011
+ Authors: Pierre Peiffer <pierre dot peiffer at stericsson dot com>
+ Philippe Langlais <philippe dot langlais at linaro dot org>
+ License: The GNU Free Documentation License, Version 1.2
+ (dual licensed under the GPL v2)
+
+Hardware overview
+=================
+ This hardware collects and provides simple tracepoints,
+ so a system processor (in our case the main ARM CPU,
+ or some small CPUs and DSPs) can write some data,
+ up to 8 bytes, into a register and out comes a log entry
+ with a time stamp (20ns resolution) on one of 256 channels. Also
+ hardware tracepoints are supported.
+
+ This module external interface is a pad on the chip
+ which complies to the MIPI System Trace Protocol v1.0
+ (see http://www.mipi.org/specifications/debug)
+ and the actual trace output can be read by an
+ electronic probe, not by software so it cannot be intercepted by
+ the CPU and reach Linux userspace.
+
+ Bandwidth depends on number of lines & bus frequency (for example on ux500
+ SoC 4 lines at max 100MHz eg max 400Mbit/s shared between 7 cores).
+ Transmit FIFO size: 256 samples up to 8 bytes.
+ On ux500 platform there is 2 contiguous STM blocks (eg 512 channels)
+
+Software Overview
+=================
+ Write atomicity and write order on STM trace channels is ensured by the fact
+ we try to allocate one channel by execution thread (no concurrent access).
+ There is 2 modes one lossless but intrusive aka Software mode and
+ another lossy mode less intrusive aka Hardware mode, by default
+ all sources are configured in Hardware mode and enabled.
+ The end of data packet is marked by a time stamp on latest byte(s) only.
+
+Kernel API
+----------
+ Configuration functions:
+ output trace clock frequency, trace mode, output port configuration
+ and enable/disable STM trace sources
+ Expose a debugfs interface too for STM trace control
+
+ Alloc/free STM trace channel functions
+
+ Set of low level atomic trace functions for 1, 2, 4 or 8 bytes
+ with & w/o time stamp
+
+ Higher level lockless trace functions:
+ stm_trace_buffer:
+ allocate a channel in 128 highest channels available
+ output the trace buffer with arbitrary length
+ (latest byte(s) automatically time stamped) then free the channel
+ stm_trace_buffer_onchannel:
+ use given channel to output the trace buffer
+ with arbitrary length (latest byte(s) automatically time stamped)
+
+ File IO output console like interface (open, close, write)
+
+ See <trace/stm.h> & drivers/misc/stm.c for more detail
+
+debugfs API
+-----------
+clockdiv:
+ This is used to set or display the current clock divisor
+ that is configured
+
+connection:
+ This is used to set or display the current output connector
+ that is configured (common values, 0 not connected, 1 for default
+ connection, 3 on Ux500 for APE MIPI34 connection)
+
+free_channels:
+ This is used to display the total number of free channels
+
+masters_enable:
+ This sets or displays whether the STM trace sources
+ are activated. Each bits represent the state of corresponding source:
+ 0 for disable or 1 to enable it.
+
+masters_modes:
+ This sets or displays the STM trace sources modes.
+ Each bits represent the mode of corresponding source:
+ 0 for Sofware lossless mode or 1 for Hardware lossy mode.
+
+User API
+--------
+ IOCTLs or debugfs for controls
+ 2 levels API for tracing:
+ - Standard write function, in this case a channel is automatically
+ allocated at first write, after you can channel number
+ with IOCTL STM_GET_CHANNEL_NO
+ - mmap for direct access of all STM trace channels port plus
+ a set of IOCTLs for alloc/free channels, in this case you can
+ write your own lib to easiest its usage
+
+Examples of using the STM
+=========================
+First mount debugfs with:
+mount -t debugfs none /sys/kernel/debug
+
+In a shell scipt
+----------------
+It's as easy as:
+ echo "My trace point" > /dev/stm0
+
+To avoid trace overflow, increase STM clock by decreasing the clockdiv with:
+ echo 1 >/sys/kernel/debug/stm/clockdiv # now use DIV2 instead of default DIV8
+If not enough you can disable some sources with:
+ echo YourEnableSources > /sys/kernel/debug/stm/masters_enable
+If always not enough the ultime intrusive way is to change the sources mode
+and set the corresponding sources in Software mode (set corresponding source
+bit to 0) with:
+ echo YourModeSources > /sys/kernel/debug/stm/masters_modes
+ (be aware some source doesn't support Software mode => keep it in HW mode)
+
+NB: on Ux500 platform, first you have to configure STM output port to switch
+APE tracing on MIPI34 connector with:
+ echo 3 > /sys/kernel/debug/stm/connection
+
+In C language
+-------------
+
+The easy way more intrusive (with STM buffer recopy):
+
+#include <trace/stm.h>
+
+int fd, i;
+char buf[1024]; // Try to align this buffer on 64 bits if possible
+
+ fd = open("/dev/stm0", O_WRONLY);
+ snprintf(buf, 1024, "STM0 Hello world\n");
+ write(fd, buf, strlen(buf));
+ ioctl(fd, STM_GET_CHANNEL_NO, &i);
+ snprintf(buf, 1024, "Use channel #%d\n", i);
+ write(fd, buf, strlen(buf));
+ close(fd);
+
+NB: You can call open("/dev/stm0", O_WRONLY) as many times as necessary
+to allocate a different channel to avoid concurrency in your
+multithreaded application.
+
+The more efficient way, use mmap'ed STM channels memory (to put in a lib):
+
+#include <trace/stm.h>
+
+int fd, i, c, l, maxChannels;
+char buf[1024]; // Try to align this buffer on 64 bits if possible
+volatile struct stm_channel *channels; // mmap'ed channels area
+
+ fd = open("/dev/stm0", O_RDWR);
+ ioctl(fd0, STM_GET_NB_MAX_CHANNELS, &maxChannels);
+ channels = (struct stm_channel *)mmap(0, maxChannels*sizeof(*channels),
+ PROT_WRITE, MAP_SHARED, fd, 0);
+ assert(channels != MAP_FAILED);
+
+ if (!ioctl(fd, STM_GET_FREE_CHANNEL, &c)) {
+ l = snprintf(buf, 1024, "STM0 Hello world on channel #%d\n", c);
+ // lazy implementation you have to send buffer by 8 Bytes when possible
+ // and be sure you don't share this channel with others threads
+ for (i=0; i<l; i++) {
+ channels[c].stamp8 = buf[i];
+ }
+ ioctl(fd, STM_RELEASE_CHANNEL, c);
+ }
+ munmap((void *)channels, maxChannels*sizeof(*channels));
+ close(fd);
+
+Kernel Internal usages
+======================
+Dynamically channels dedicated for the kernel are allocated
+in the 128 highest ones
+
+Via menuconfig you can:
+- Duplicate printk output on a STM dedicated channel (255)
+- Have realtime ftrace output to a STM dedicated channel (254),
+ if corresponding TRACER is enabled
+- Have realtime sched context switch & sched wakeup output on dedicated channels
+ (253, 252), if corresponding TRACER is enabled
+- Have Stack Trace on dedicated channels (251)
+- Duplicate trace_printk output on dedicated channels (250 & 249)
+
+
+And in the future:
+------------------
+- Use it in standard kernel tracing infrastucture,
+ possibilities:
+ - Insert other STM trace calls before trace ring buffer write
+ - Substitute time stamping & trace ring buffer by STM
+
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index cc8e49d..70a9527 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -452,6 +452,7 @@ config PCH_PHUB
To compile this driver as a module, choose M here: the module will
be called pch_phub.
+source "drivers/misc/Kconfig.stm"
source "drivers/misc/c2port/Kconfig"
source "drivers/misc/eeprom/Kconfig"
source "drivers/misc/cb710/Kconfig"
diff --git a/drivers/misc/Kconfig.stm b/drivers/misc/Kconfig.stm
new file mode 100644
index 0000000..ef2b946
--- /dev/null
+++ b/drivers/misc/Kconfig.stm
@@ -0,0 +1,114 @@
+menuconfig STM_TRACE
+ bool "STM MIPI Trace driver"
+ depends on ARCH_U8500
+ help
+ Simple System Trace Module driver. It allows to use and configure the
+ STM, either from kernel space, or from user space.
+
+if STM_TRACE
+
+config STM_NUMBER_OF_CHANNEL
+ int
+ default 512 if ARCH_U8500
+ default 256
+ help
+ Number Max of channels always a multiple of 256
+
+config STM_PRINTK
+ bool "printk support"
+ depends on STM_TRACE
+ help
+ Duplicate printk output on STM printk channel & activate stm_printk
+
+config STM_PRINTK_CHANNEL
+ int "printk channel"
+ range 0 255
+ depends on STM_PRINTK
+ default 255
+ help
+ STM printk channel number
+
+config STM_FTRACE
+ bool "functions tracing"
+ depends on FTRACE
+ default y
+ help
+ Output function tracing on STM dedicated channel
+
+config STM_FTRACE_CHANNEL
+ int "ftrace channel"
+ range 0 255
+ depends on STM_FTRACE
+ default 254
+ help
+ STM ftrace channel number
+
+config STM_CTX_SWITCH
+ bool "Context switch tracing"
+ depends on CONTEXT_SWITCH_TRACER
+ default y
+ help
+ Output scheduler context switch on STM dedicated channel
+
+config STM_CTX_SWITCH_CHANNEL
+ int "Context switch channel"
+ range 0 255
+ depends on STM_CTX_SWITCH
+ default 253
+ help
+ STM Context switch channel number
+
+config STM_WAKEUP
+ bool "Scheduler wakeup tracing"
+ depends on CONTEXT_SWITCH_TRACER
+ default y
+ help
+ Output scheduler wakeup on STM dedicated channel
+
+config STM_WAKEUP_CHANNEL
+ int "Wakeup channel"
+ range 0 255
+ depends on STM_WAKEUP
+ default 252
+ help
+ STM scheduler wakeup channel number
+
+config STM_STACK_TRACE
+ bool "Stack tracing"
+ depends on STACKTRACE
+ default y
+ help
+ Output stack tracing on STM dedicated channel
+
+config STM_STACK_TRACE_CHANNEL
+ int "Stack trace channel"
+ range 0 255
+ depends on STM_STACK_TRACE
+ default 251
+ help
+ STM stack trace channel number
+
+config STM_TRACE_PRINTK
+ bool "trace printk & binary printk support"
+ depends on TRACING
+ default y
+ help
+ Duplicate trace printk output on STM printk channel
+
+config STM_TRACE_PRINTK_CHANNEL
+ int "trace_printk channel"
+ range 0 255
+ depends on TRACING
+ default 250
+ help
+ STM trace_printk channel number
+
+config STM_TRACE_BPRINTK_CHANNEL
+ int "trace_bprintk channel"
+ range 0 255
+ depends on TRACING
+ default 249
+ help
+ STM trace binary printk channel number
+
+endif
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 98009cc..0b5c3e9 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -42,3 +42,4 @@ obj-$(CONFIG_ARM_CHARLCD) += arm-charlcd.o
obj-$(CONFIG_PCH_PHUB) += pch_phub.o
obj-y += ti-st/
obj-$(CONFIG_AB8500_PWM) += ab8500-pwm.o
+obj-$(CONFIG_STM_TRACE) += stm.o
diff --git a/drivers/misc/stm.c b/drivers/misc/stm.c
new file mode 100644
index 0000000..a05b2d1
--- /dev/null
+++ b/drivers/misc/stm.c
@@ -0,0 +1,797 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ * Author: Pierre Peiffer <pierre.peiffer@xxxxxxxxxxxxxx> for ST-Ericsson.
+ * Philippe Langlais <philippe.Langlais@xxxxxxxxxxxxxx> for ST-Ericsson.
+ * License terms: GNU General Public License (GPL), version 2.
+ */
+
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/cdev.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/debugfs.h>
+#include <trace/stm.h>
+
+/* STM Registers */
+#define STM_CR (stm.virtbase)
+#define STM_MMC (stm.virtbase + 0x008)
+#define STM_TER (stm.virtbase + 0x010)
+#define STMPERIPHID0 (stm.virtbase + 0xFC0)
+#define STMPERIPHID1 (stm.virtbase + 0xFC8)
+#define STMPERIPHID2 (stm.virtbase + 0xFD0)
+#define STMPERIPHID3 (stm.virtbase + 0xFD8)
+#define STMPCELLID0 (stm.virtbase + 0xFE0)
+#define STMPCELLID1 (stm.virtbase + 0xFE8)
+#define STMPCELLID2 (stm.virtbase + 0xFF0)
+#define STMPCELLID3 (stm.virtbase + 0xFF8)
+
+#define STM_CLOCK_SHIFT 6
+#define STM_CLOCK_MASK 0x1C0
+
+/* Hardware mode for all sources */
+#define STM_MMC_DEFAULT 0xFFFFFFFF
+
+/* Max number of channels (multiple of 256) */
+#define STM_NUMBER_OF_CHANNEL CONFIG_STM_NUMBER_OF_CHANNEL
+
+/* # dynamically allocated channel with stm_trace_buffer */
+#define NB_KERNEL_DYNAMIC_CHANNEL 128
+
+static struct stm_device {
+ const struct stm_platform_data *pdata;
+ void __iomem *virtbase;
+ /* Used to register the allocated channels */
+ DECLARE_BITMAP(ch_bitmap, STM_NUMBER_OF_CHANNEL);
+} stm;
+
+volatile struct stm_channel __iomem *stm_channels;
+
+static struct cdev cdev;
+static struct class *stm_class;
+static int stm_major;
+
+static DEFINE_SPINLOCK(lock);
+
+/* Middle value for clock divisor */
+static enum clock_div stm_clockdiv = STM_CLOCK_DIV8;
+
+/* Default value for STM output connection */
+static enum stm_connection_type stm_connection = STM_DEFAULT_CONNECTION;
+
+#define STM_BUFSIZE 256
+struct channel_data {
+ DECLARE_BITMAP(bitmap, STM_NUMBER_OF_CHANNEL);
+ int numero;
+ spinlock_t lock;
+ u8 data_buffer[STM_BUFSIZE];
+};
+
+static u64 stm_printk_buf[1024/sizeof(u64)];
+static arch_spinlock_t stm_buf_lock =
+ (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
+
+int stm_alloc_channel(int offset)
+{
+ int channel;
+
+ /* Look for a free channel from offset */
+ do {
+ channel = find_next_zero_bit(stm.ch_bitmap,
+ STM_NUMBER_OF_CHANNEL, offset);
+ } while ((channel < STM_NUMBER_OF_CHANNEL)
+ && test_and_set_bit(channel, stm.ch_bitmap));
+ return channel;
+}
+EXPORT_SYMBOL(stm_alloc_channel);
+
+void stm_free_channel(int channel)
+{
+ clear_bit(channel, stm.ch_bitmap);
+}
+EXPORT_SYMBOL(stm_free_channel);
+
+static int stm_get_channel(struct channel_data *ch_data, int __user *arg)
+{
+ int channel, err;
+
+ channel = stm_alloc_channel(0);
+ if (channel < STM_NUMBER_OF_CHANNEL) {
+ /* One free found ! */
+ err = put_user(channel, arg);
+ if (err)
+ stm_free_channel(channel);
+ else
+ /* Register it in the context of the file */
+ set_bit(channel, ch_data->bitmap);
+ } else
+ err = -ENOMEM;
+ return err;
+}
+
+static int stm_release_channel(struct channel_data *ch_data, int channel)
+{
+ if ((channel < 0) || (channel >= STM_NUMBER_OF_CHANNEL))
+ return -EINVAL;
+ stm_free_channel(channel);
+ clear_bit(channel, ch_data->bitmap);
+ return 0;
+}
+
+/*
+ * Trace a buffer on a given channel
+ * with auto time stamping on last byte(s) only
+ */
+int stm_trace_buffer_onchannel(int channel,
+ const void *data, size_t length)
+{
+ int i, mod64;
+ volatile struct stm_channel __iomem *pch;
+
+ if (channel >= STM_NUMBER_OF_CHANNEL || !stm_channels)
+ return 0;
+
+ pch = &stm_channels[channel];
+
+ /* Align data pointer to u64 & time stamp last byte(s) */
+ mod64 = (int)data & 7;
+ i = length - 8 + mod64;
+ switch (mod64) {
+ case 0:
+ if (i)
+ pch->no_stamp64 = *(u64 *)data;
+ else {
+ pch->stamp64 = *(u64 *)data;
+ return length;
+ }
+ data += 8;
+ break;
+ case 1:
+ pch->no_stamp8 = *(u8 *)data;
+ pch->no_stamp16 = *(u16 *)(data+1);
+ if (i)
+ pch->no_stamp32 = *(u32 *)(data+3);
+ else {
+ pch->stamp32 = *(u32 *)(data+3);
+ return length;
+ }
+ data += 7;
+ break;
+ case 2:
+ pch->no_stamp16 = *(u16 *)data;
+ if (i)
+ pch->no_stamp32 = *(u32 *)(data+2);
+ else {
+ pch->stamp32 = *(u32 *)(data+2);
+ return length;
+ }
+ data += 6;
+ break;
+ case 3:
+ pch->no_stamp8 = *(u8 *)data;
+ if (i)
+ pch->no_stamp32 = *(u32 *)(data+1);
+ else {
+ pch->stamp32 = *(u32 *)(data+1);
+ return length;
+ }
+ data += 5;
+ break;
+ case 4:
+ if (i)
+ pch->no_stamp32 = *(u32 *)data;
+ else {
+ pch->stamp32 = *(u32 *)data;
+ return length;
+ }
+ data += 4;
+ break;
+ case 5:
+ pch->no_stamp8 = *(u8 *)data;
+ if (i)
+ pch->no_stamp16 = *(u16 *)(data+1);
+ else {
+ pch->stamp16 = *(u16 *)(data+1);
+ return length;
+ }
+ data += 3;
+ break;
+ case 6:
+ if (i)
+ pch->no_stamp16 = *(u16 *)data;
+ else {
+ pch->stamp16 = *(u16 *)data;
+ return length;
+ }
+ data += 2;
+ break;
+ case 7:
+ if (i)
+ pch->no_stamp8 = *(u8 *)data;
+ else {
+ pch->stamp8 = *(u8 *)data;
+ return length;
+ }
+ data++;
+ break;
+ }
+ for (;;) {
+ if (i > 8) {
+ pch->no_stamp64 = *(u64 *)data;
+ data += 8;
+ i -= 8;
+ } else if (i == 8) {
+ pch->stamp64 = *(u64 *)data;
+ break;
+ } else if (i > 4) {
+ pch->no_stamp32 = *(u32 *)data;
+ data += 4;
+ i -= 4;
+ } else if (i == 4) {
+ pch->stamp32 = *(u32 *)data;
+ break;
+ } else if (i > 2) {
+ pch->no_stamp16 = *(u16 *)data;
+ data += 2;
+ i -= 2;
+ } else if (i == 2) {
+ pch->stamp16 = *(u16 *)data;
+ break;
+ } else {
+ pch->stamp8 = *(u8 *)data;
+ break;
+ }
+ }
+ return length;
+}
+EXPORT_SYMBOL(stm_trace_buffer_onchannel);
+
+static int stm_open(struct inode *inode, struct file *file)
+{
+ struct channel_data *channel_data;
+
+ channel_data = kzalloc(sizeof(struct channel_data), GFP_KERNEL);
+ if (channel_data == NULL)
+ return -ENOMEM;
+
+ spin_lock_init(&channel_data->lock);
+ channel_data->numero = -1; /* Channel not yet allocated */
+ file->private_data = channel_data;
+
+ return 0;
+}
+
+static int stm_release(struct inode *inode, struct file *file)
+{
+ struct channel_data *channel;
+
+ channel = (struct channel_data *)file->private_data;
+
+ /* Free allocated channel if necessary */
+ if (channel->numero != -1)
+ stm_free_channel(channel->numero);
+
+ bitmap_andnot(stm.ch_bitmap, stm.ch_bitmap,
+ channel->bitmap, STM_NUMBER_OF_CHANNEL);
+
+ kfree(channel);
+ return 0;
+}
+
+static ssize_t stm_write(struct file *file, const char __user *buf,
+ size_t size, loff_t *off)
+{
+ struct channel_data *channel = file->private_data;
+
+ /* Alloc channel at first write */
+ if (channel->numero == -1) {
+ channel->numero = stm_alloc_channel(0);
+ if (channel->numero > STM_NUMBER_OF_CHANNEL)
+ return -ENOMEM;
+ }
+
+ if (size > STM_BUFSIZE)
+ size = STM_BUFSIZE;
+
+ spin_lock(&channel->lock);
+
+ if (copy_from_user
+ (channel->data_buffer, (void __user *) buf, size)) {
+ spin_unlock(&channel->lock);
+ return -EFAULT;
+ }
+ size = stm_trace_buffer_onchannel(channel->numero,
+ channel->data_buffer, size);
+
+ spin_unlock(&channel->lock);
+
+ return size;
+}
+
+static int stm_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ /*
+ * Don't allow a mapping that covers more than the STM channels
+ */
+ if ((vma->vm_end - vma->vm_start) >
+ STM_NUMBER_OF_CHANNEL*sizeof(struct stm_channel))
+ return -EINVAL;
+
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+ if (io_remap_pfn_range(vma, vma->vm_start,
+ stm.pdata->channels_phys_base>>PAGE_SHIFT,
+ STM_NUMBER_OF_CHANNEL*sizeof(struct stm_channel),
+ vma->vm_page_prot))
+ return -EAGAIN;
+
+ return 0;
+}
+
+/* Enable the trace for given sources (bitfield) */
+static void stm_enable_src(unsigned int v)
+{
+ unsigned int cr_val;
+ spin_lock(&lock);
+ cr_val = readl(STM_CR);
+ cr_val &= ~STM_CLOCK_MASK;
+ writel(cr_val|(stm_clockdiv<<STM_CLOCK_SHIFT), STM_CR);
+ writel(v, STM_TER);
+ spin_unlock(&lock);
+}
+
+/* Disable all sources */
+static void stm_disable_src(void)
+{
+ writel(0x0, STM_CR); /* stop clock */
+ writel(0x0, STM_TER); /* Disable cores */
+}
+
+/* Set clock speed */
+static int stm_set_ckdiv(enum clock_div v)
+{
+ unsigned int val;
+
+ spin_lock(&lock);
+ val = readl(STM_CR);
+ val &= ~STM_CLOCK_MASK;
+ writel(val | ((v << STM_CLOCK_SHIFT) & STM_CLOCK_MASK), STM_CR);
+ spin_unlock(&lock);
+ stm_clockdiv = v;
+
+ return 0;
+}
+
+/* Return the control register */
+static inline unsigned int stm_get_cr(void)
+{
+ return readl(STM_CR);
+}
+
+/*
+ * Set Trace MODE lossless/lossy (Software/Hardware)
+ * each bit represent the corresponding mode of this source
+ */
+static inline void stm_set_modes(unsigned int modes)
+{
+ writel(modes, STM_MMC);
+}
+
+/* Get Trace MODE lossless/lossy (Software/Hardware)
+ * each bit represent the corresponding mode of this source */
+static inline unsigned int stm_get_modes(void)
+{
+ return readl(STM_MMC);
+}
+
+/* Count # of free channels */
+static int stm_nb_free_channels(void)
+{
+ int nb_channels, offset;
+
+ nb_channels = 0;
+ offset = 0;
+ for (;;) {
+ offset = find_next_zero_bit(stm.ch_bitmap,
+ STM_NUMBER_OF_CHANNEL, offset);
+ if (offset == STM_NUMBER_OF_CHANNEL)
+ break;
+ offset++;
+ nb_channels++;
+ }
+ return nb_channels;
+}
+
+static long stm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ int err = 0;
+ struct channel_data *channel = file->private_data;
+
+ switch (cmd) {
+
+ case STM_CONNECTION:
+ if (stm.pdata->stm_connection)
+ stm.pdata->stm_connection(arg);
+ stm_connection = arg;
+ break;
+
+ case STM_DISABLE:
+ stm_disable_src();
+ break;
+
+ case STM_GET_NB_MAX_CHANNELS:
+ err = put_user(STM_NUMBER_OF_CHANNEL, (unsigned int *)arg);
+ break;
+
+ case STM_GET_NB_FREE_CHANNELS:
+ err = put_user(stm_nb_free_channels(), (unsigned int *)arg);
+ break;
+
+ case STM_GET_CHANNEL_NO:
+ err = put_user(channel->numero, (unsigned int *)arg);
+ break;
+
+ case STM_SET_CLOCK_DIV:
+ err = stm_set_ckdiv((enum clock_div) arg);
+ break;
+
+ case STM_SET_MODE:
+ stm_set_modes(arg);
+ break;
+
+ case STM_GET_MODE:
+ err = put_user(stm_get_modes(), (unsigned int *)arg);
+ break;
+
+ case STM_GET_CTRL_REG:
+ err = put_user(stm_get_cr(), (unsigned int *)arg);
+ break;
+
+ case STM_ENABLE_SRC:
+ stm_enable_src(arg);
+ break;
+
+ case STM_GET_FREE_CHANNEL:
+ err = stm_get_channel(channel, (int *)arg);
+ break;
+
+ case STM_RELEASE_CHANNEL:
+ err = stm_release_channel(channel, arg);
+ break;
+
+ default:
+ err = -EINVAL;
+ break;
+ }
+
+ return err;
+}
+
+/*
+ * Trace a buffer on a dynamically allocated channel
+ * with auto time stamping on the first byte(s) only
+ * Dynamic channel number >=
+ * STM_NUMBER_OF_CHANNEL - NB_KERNEL_DYNAMIC_CHANNEL
+ */
+int stm_trace_buffer(const void *data, size_t length)
+{
+ int channel;
+
+ channel = stm_alloc_channel(STM_NUMBER_OF_CHANNEL
+ - NB_KERNEL_DYNAMIC_CHANNEL);
+ if (channel < STM_NUMBER_OF_CHANNEL) {
+ length = stm_trace_buffer_onchannel(channel, data, length);
+ stm_free_channel(channel);
+ return length;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(stm_trace_buffer);
+
+static const struct file_operations stm_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = stm_ioctl,
+ .open = stm_open,
+ .llseek = no_llseek,
+ .write = stm_write,
+ .release = stm_release,
+ .mmap = stm_mmap,
+};
+
+/*
+ * Init and deinit driver
+ */
+
+static int __devinit stm_probe(struct platform_device *pdev)
+{
+ int retval = 0;
+
+ if (!pdev || !pdev->dev.platform_data) {
+ pr_alert("No device/platform_data found on STM driver\n");
+ return -ENODEV;
+ }
+
+ stm.pdata = pdev->dev.platform_data;
+
+ cdev_init(&cdev, &stm_fops);
+ cdev.owner = THIS_MODULE;
+
+ stm_channels =
+ ioremap_nocache(stm.pdata->channels_phys_base,
+ STM_NUMBER_OF_CHANNEL*sizeof(*stm_channels));
+ if (stm_channels == NULL) {
+ dev_err(&pdev->dev, "could not remap STM Msg register\n");
+ return -ENODEV;
+ }
+
+ stm.virtbase = ioremap_nocache(stm.pdata->regs_phys_base, SZ_4K);
+ if (stm.virtbase == NULL) {
+ retval = -EIO;
+ dev_err(&pdev->dev, "could not remap STM Register\n");
+ goto err_channels;
+ }
+
+ retval = cdev_add(&cdev, MKDEV(stm_major, 0), 1);
+ if (retval) {
+ dev_err(&pdev->dev, "chardev registration failed\n");
+ goto err_channels;
+ }
+
+ if (IS_ERR(device_create(stm_class, &pdev->dev,
+ MKDEV(stm_major, 0), NULL, STM_DEV_NAME)))
+ dev_err(&pdev->dev, "can't create device\n");
+
+ /* Check chip IDs if necessary */
+ if (stm.pdata->id_mask) {
+ u32 periph_id, cell_id;
+
+ periph_id = (readb(STMPERIPHID3)<<24) +
+ (readb(STMPERIPHID2)<<16) +
+ (readb(STMPERIPHID1)<<8) +
+ readb(STMPERIPHID0);
+ cell_id = (readb(STMPCELLID3)<<24) +
+ (readb(STMPCELLID2)<<16) +
+ (readb(STMPCELLID1)<<8) +
+ readb(STMPCELLID0);
+ /* Only warns if it isn't a ST-Ericsson supported one */
+ if ((periph_id & stm.pdata->id_mask) != 0x00080dec ||
+ cell_id != 0xb105f00d) {
+ dev_warn(&pdev->dev, "STM-Trace IC not compatible\n");
+ dev_warn(&pdev->dev, "periph_id=%x\n", periph_id);
+ dev_warn(&pdev->dev, "pcell_id=%x\n", cell_id);
+ }
+ }
+
+ /* Reserve channels if necessary */
+ if (stm.pdata->channels_reserved_sz) {
+ int i;
+
+ for (i = 0; i < stm.pdata->channels_reserved_sz; i++) {
+ set_bit(stm.pdata->channels_reserved[i],
+ stm.ch_bitmap);
+ }
+ }
+ /* Reserve kernel trace channels on demand */
+#ifdef CONFIG_STM_PRINTK
+ set_bit(CONFIG_STM_PRINTK_CHANNEL, stm.ch_bitmap);
+#endif
+#ifdef CONFIG_STM_FTRACE
+ set_bit(CONFIG_STM_FTRACE_CHANNEL, stm.ch_bitmap);
+#endif
+#ifdef CONFIG_STM_CTX_SWITCH
+ set_bit(CONFIG_STM_CTX_SWITCH_CHANNEL, stm.ch_bitmap);
+#endif
+#ifdef CONFIG_STM_WAKEUP
+ set_bit(CONFIG_STM_WAKEUP_CHANNEL, stm.ch_bitmap);
+#endif
+#ifdef CONFIG_STM_STACK_TRACE
+ set_bit(CONFIG_STM_STACK_TRACE_CHANNEL, stm.ch_bitmap);
+#endif
+#ifdef CONFIG_STM_TRACE_PRINTK
+ set_bit(CONFIG_STM_TRACE_PRINTK_CHANNEL, stm.ch_bitmap);
+ set_bit(CONFIG_STM_TRACE_BPRINTK_CHANNEL, stm.ch_bitmap);
+#endif
+
+ if (stm.pdata->stm_connection) {
+ retval = stm.pdata->stm_connection(stm_connection);
+ if (retval) {
+ dev_err(&pdev->dev, "failed to connect STM output\n");
+ goto err_channels;
+ }
+ }
+
+ /* Enable STM Masters given in pdata */
+ if (stm.pdata->masters_enabled)
+ stm_enable_src(stm.pdata->masters_enabled);
+
+ stm_set_modes(STM_MMC_DEFAULT); /* Set all sources in HW mode */
+
+ dev_info(&pdev->dev, "STM-Trace driver probed successfully\n");
+ stm_printk("STM-Trace driver initialized\n");
+ return 0;
+
+err_channels:
+ iounmap(stm_channels);
+ return retval;
+}
+
+static int __devexit stm_remove(struct platform_device *pdev)
+{
+ device_destroy(stm_class, MKDEV(stm_major, 0));
+ cdev_del(&cdev);
+
+ if (stm.pdata->stm_connection)
+ (void) stm.pdata->stm_connection(STM_DISCONNECT);
+
+ stm_disable_src();
+ iounmap(stm.virtbase);
+ iounmap(stm_channels);
+
+ return 0;
+}
+
+int stm_printk(const char *fmt, ...)
+{
+ int ret;
+ size_t size;
+ va_list args;
+
+ va_start(args, fmt);
+ arch_spin_lock(&stm_buf_lock);
+ size = vscnprintf((char *)stm_printk_buf,
+ sizeof(stm_printk_buf), fmt, args);
+ ret = stm_trace_buffer(stm_printk_buf, size);
+ arch_spin_unlock(&stm_buf_lock);
+ va_end(args);
+ return ret;
+}
+EXPORT_SYMBOL(stm_printk);
+
+/*
+ * Debugfs interface
+ */
+
+static int stm_connection_show(void *data, u64 *val)
+{
+ *val = stm_connection;
+ return 0;
+}
+
+static int stm_connection_set(void *data, u64 val)
+{
+ if (stm.pdata->stm_connection) {
+ stm_connection = val;
+ stm.pdata->stm_connection(val);
+ }
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(stm_connection_fops, stm_connection_show,
+ stm_connection_set, "%llu\n");
+
+static int stm_clockdiv_show(void *data, u64 *val)
+{
+ *val = stm_clockdiv;
+ return 0;
+}
+
+static int stm_clockdiv_set(void *data, u64 val)
+{
+ stm_set_ckdiv(val);
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(stm_clockdiv_fops, stm_clockdiv_show,
+ stm_clockdiv_set, "%llu\n");
+
+static int stm_masters_enable_show(void *data, u64 *val)
+{
+ *val = readl(STM_TER);
+ return 0;
+}
+
+static int stm_masters_enable_set(void *data, u64 val)
+{
+ stm_enable_src(val);
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(stm_masters_enable_fops, stm_masters_enable_show,
+ stm_masters_enable_set, "%08llx\n");
+
+static int stm_masters_modes_show(void *data, u64 *val)
+{
+ *val = stm_get_modes();
+ return 0;
+}
+
+static int stm_masters_modes_set(void *data, u64 val)
+{
+ stm_set_modes(val);
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(stm_masters_modes_fops, stm_masters_modes_show,
+ stm_masters_modes_set, "%08llx\n");
+
+/* Count # of free channels */
+static int stm_free_channels_show(void *data, u64 *val)
+{
+ *val = stm_nb_free_channels();
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(stm_free_channels_fops, stm_free_channels_show,
+ NULL, "%lld\n");
+
+static __init int stm_init_debugfs(void)
+{
+ struct dentry *d_stm;
+
+ d_stm = debugfs_create_dir(STM_DEV_NAME, NULL);
+ if (!d_stm)
+ return -ENOMEM;
+
+ (void) debugfs_create_file("connection", S_IRUGO | S_IWUGO, d_stm,
+ NULL, &stm_connection_fops);
+ (void) debugfs_create_file("clockdiv", S_IRUGO | S_IWUGO, d_stm,
+ NULL, &stm_clockdiv_fops);
+ (void) debugfs_create_file("masters_enable", S_IRUGO | S_IWUGO, d_stm,
+ NULL, &stm_masters_enable_fops);
+ (void) debugfs_create_file("masters_modes", S_IRUGO | S_IWUGO, d_stm,
+ NULL, &stm_masters_modes_fops);
+ (void) debugfs_create_file("free_channels", S_IRUGO, d_stm,
+ NULL, &stm_free_channels_fops);
+ return 0;
+}
+fs_initcall(stm_init_debugfs);
+
+static struct platform_driver stm_driver = {
+ .probe = stm_probe,
+ .remove = __devexit_p(stm_remove),
+ .driver = {
+ .name = STM_DEV_NAME,
+ .owner = THIS_MODULE,
+ }
+};
+
+static int __init stm_init(void)
+{
+ int retval;
+ dev_t dev;
+
+ stm_class = class_create(THIS_MODULE, STM_DEV_NAME);
+ if (IS_ERR(stm_class)) {
+ pr_err("stm: can't register stm class\n");
+ return PTR_ERR(stm_class);
+ }
+
+ retval = alloc_chrdev_region(&dev, 0, 1, STM_DEV_NAME);
+ if (retval) {
+ pr_err("stm: can't register character device\n");
+ class_destroy(stm_class);
+ return retval;
+ }
+ stm_major = MAJOR(dev);
+ return platform_driver_register(&stm_driver);
+}
+
+static void __exit stm_exit(void)
+{
+ platform_driver_unregister(&stm_driver);
+ unregister_chrdev_region(MKDEV(stm_major, 0), 1);
+ class_destroy(stm_class);
+}
+
+arch_initcall(stm_init); /* STM init ASAP need to wait GPIO init */
+module_exit(stm_exit);
+
+MODULE_AUTHOR("Paul Ghaleb - ST Microelectronics");
+MODULE_AUTHOR("Pierre Peiffer - ST-Ericsson");
+MODULE_AUTHOR("Philippe Langlais - ST-Ericsson");
+MODULE_DESCRIPTION("System Trace Module driver");
+MODULE_ALIAS("stm");
+MODULE_ALIAS("stm-trace");
+MODULE_LICENSE("GPL v2");
diff --git a/include/Kbuild b/include/Kbuild
index 8d226bf..506f6d7 100644
--- a/include/Kbuild
+++ b/include/Kbuild
@@ -10,3 +10,4 @@ header-y += video/
header-y += drm/
header-y += xen/
header-y += scsi/
+header-y += trace/
diff --git a/include/trace/Kbuild b/include/trace/Kbuild
new file mode 100644
index 0000000..7e8b704
--- /dev/null
+++ b/include/trace/Kbuild
@@ -0,0 +1 @@
+header-y += stm.h
diff --git a/include/trace/stm.h b/include/trace/stm.h
new file mode 100644
index 0000000..3362de0
--- /dev/null
+++ b/include/trace/stm.h
@@ -0,0 +1,223 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * ST-Ericsson STM Trace driver
+ *
+ * Author: Pierre Peiffer <pierre.peiffer@xxxxxxxxxxxxxx> for ST-Ericsson.
+ * Philippe Langlais <philippe.langlais@xxxxxxxxxxxxxx> for ST-Ericsson.
+ * License terms: GNU General Public License (GPL), version 2.
+ */
+
+#ifndef STM_H
+#define STM_H
+
+#define STM_DEV_NAME "stm"
+
+/* One single channel mapping */
+struct stm_channel {
+ union {
+ __u8 no_stamp8;
+ __u16 no_stamp16;
+ __u32 no_stamp32;
+ __u64 no_stamp64;
+ };
+ union {
+ __u8 stamp8;
+ __u16 stamp16;
+ __u32 stamp32;
+ __u64 stamp64;
+ };
+};
+
+/* Possible trace modes */
+#define STM_SW_LOSSLESS 0 /* Software mode: lossless data but intrusive */
+#define STM_HW_LOSSY 1 /* Hardware mode: lossy data but less intrusive */
+
+/* Possible clock setting */
+enum clock_div {
+ STM_CLOCK_DIV2 = 0,
+ STM_CLOCK_DIV4,
+ STM_CLOCK_DIV6,
+ STM_CLOCK_DIV8,
+ STM_CLOCK_DIV10,
+ STM_CLOCK_DIV12,
+ STM_CLOCK_DIV14,
+ STM_CLOCK_DIV16,
+};
+
+/* ioctl commands */
+#define STM_CONNECTION _IOW('t', 0, enum stm_connection_type)
+#define STM_DISABLE _IO('t', 1)
+#define STM_GET_NB_MAX_CHANNELS _IOR('t', 2, int)
+#define STM_GET_NB_FREE_CHANNELS _IOR('t', 3, int)
+#define STM_GET_CHANNEL_NO _IOR('t', 4, int)
+#define STM_SET_CLOCK_DIV _IOW('t', 5, enum clock_div)
+#define STM_GET_CTRL_REG _IOR('t', 6, int)
+#define STM_ENABLE_SRC _IOWR('t', 7, int)
+#define STM_GET_FREE_CHANNEL _IOW('t', 8, int)
+#define STM_RELEASE_CHANNEL _IOW('t', 9, int)
+#define STM_SET_MODE _IOWR('t', 10, int)
+#define STM_GET_MODE _IOR('t', 11, int)
+
+enum stm_connection_type {
+ STM_DISCONNECT = 0,
+ STM_DEFAULT_CONNECTION = 1,
+ STM_STE_MODEM_ON_MIPI34_NONE_ON_MIPI60 = 2,
+ STM_STE_APE_ON_MIPI34_NONE_ON_MIPI60 = 3,
+ STM_STE_MODEM_ON_MIPI34_APE_ON_MIPI60 = 4
+};
+
+#ifdef __KERNEL__
+
+struct stm_platform_data {
+ u32 regs_phys_base;
+ u32 channels_phys_base;
+ u32 id_mask;
+ u32 masters_enabled;
+ const s16 *channels_reserved;
+ int channels_reserved_sz;
+ int (*stm_connection)(enum stm_connection_type);
+};
+
+/* Channels base address */
+extern volatile struct stm_channel __iomem *stm_channels;
+
+/* Provides stm_trace_XX() and stm_tracet_XX() trace API */
+#define DEFLLTFUN(size) \
+static inline void stm_trace_##size(int channel, __u##size data) \
+{ \
+ stm_channels[channel].no_stamp##size = data; \
+} \
+static inline void stm_tracet_##size(int channel, __u##size data) \
+{ \
+ stm_channels[channel].stamp##size = data; \
+} \
+
+DEFLLTFUN(8);
+DEFLLTFUN(16);
+DEFLLTFUN(32);
+DEFLLTFUN(64);
+
+/*
+ * Trace a buffer on a given channel
+ * with auto time stamping on the first byte(s) only
+ */
+int stm_trace_buffer_onchannel(int channel, const void *data, size_t length);
+/*
+ * Trace a buffer on a dynamically allocated channel
+ * with auto time stamping on the first byte(s) only
+ * Dynamic channel are allocated in the 128 highest channels
+ */
+int stm_trace_buffer(const void *data, size_t length);
+
+/* printk equivalent for STM */
+int stm_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
+
+#if defined(CONFIG_STM_PRINTK)
+#define stm_dup_printk(buf, length) \
+ stm_trace_buffer_onchannel(CONFIG_STM_PRINTK_CHANNEL, buf, length)
+
+#else
+static inline int stm_dup_printk(char *buf, size_t size)
+{
+ return 0;
+}
+#endif
+
+#if defined(CONFIG_STM_TRACE_PRINTK)
+static inline int stm_trace_printk_buf(
+ unsigned long ip, const char *buf, size_t size)
+{
+ stm_trace_32(CONFIG_STM_TRACE_PRINTK_CHANNEL, ip);
+ return stm_trace_buffer_onchannel(CONFIG_STM_TRACE_PRINTK_CHANNEL,
+ buf, size);
+}
+
+static inline int stm_trace_bprintk_buf(
+ unsigned long ip, const char *fmt, const void *buf, size_t size)
+{
+ stm_trace_64(CONFIG_STM_TRACE_BPRINTK_CHANNEL, ((u64)ip<<32)+(u32)fmt);
+ return stm_trace_buffer_onchannel(CONFIG_STM_TRACE_PRINTK_CHANNEL,
+ buf, size);
+}
+#else
+static inline int stm_trace_printk_buf(
+ unsigned long ip, const char *buf, size_t size)
+{
+ return 0;
+}
+
+static inline int stm_trace_bprintk_buf(
+ unsigned long ip, const char *fmt, const char *buf, size_t size)
+{
+ return 0;
+}
+#endif
+
+#if defined(CONFIG_STM_FTRACE)
+static inline void stm_ftrace(unsigned long ip, unsigned long parent_ip)
+{
+ stm_tracet_64(CONFIG_STM_FTRACE_CHANNEL, (((__u64)ip)<<32) + parent_ip);
+}
+#else
+static inline void stm_ftrace(unsigned long ip, unsigned long parent_ip)
+{
+}
+#endif
+
+#if defined(CONFIG_STM_CTX_SWITCH)
+static inline void stm_sched_switch(u32 prev_pid, u8 prev_prio, u8 prev_state,
+ u32 next_pid, u8 next_prio, u8 next_state, u32 next_cpu)
+{
+ stm_trace_64(CONFIG_STM_CTX_SWITCH_CHANNEL,
+ (((__u64)prev_pid)<<32) + next_pid);
+ stm_tracet_64(CONFIG_STM_CTX_SWITCH_CHANNEL, (((__u64)next_cpu)<<32)
+ + (prev_prio<<24) + (prev_state<<16)
+ + (next_prio<<8) + next_state);
+}
+#else
+static inline void stm_sched_switch(u32 prev_pid, u8 prev_prio, u8 prev_state,
+ u32 next_pid, u8 next_prio, u8 next_state, u32 next_cpu)
+{
+}
+#endif
+
+#if defined(CONFIG_STM_WAKEUP)
+static inline void stm_sched_wakeup(u32 prev_pid, u8 prev_prio, u8 prev_state,
+ u32 next_pid, u8 next_prio, u8 next_state, u32 next_cpu)
+{
+ stm_trace_64(CONFIG_STM_WAKEUP_CHANNEL,
+ (((__u64)prev_pid)<<32) + next_pid);
+ stm_tracet_64(CONFIG_STM_WAKEUP_CHANNEL, (((__u64)next_cpu)<<32)
+ + (prev_prio<<24) + (prev_state<<16)
+ + (next_prio<<8) + next_state);
+}
+#else
+static inline void stm_sched_wakeup(u32 prev_pid, u8 prev_prio, u8 prev_state,
+ u32 next_pid, u8 next_prio, u8 next_state, u32 next_cpu)
+{
+}
+#endif
+
+#if defined(CONFIG_STM_STACK_TRACE)
+static inline void stm_stack_trace(unsigned long *callers)
+{
+ while (*(callers + 1) != ULONG_MAX) {
+ stm_trace_32(CONFIG_STM_STACK_TRACE_CHANNEL, *callers++);
+ }
+ /* Time stamp the latest */
+ stm_tracet_32(CONFIG_STM_STACK_TRACE_CHANNEL, *callers);
+}
+#else
+static inline void stm_stack_trace(unsigned long *callers)
+{
+}
+#endif
+
+/* Alloc/Free STM channel */
+int stm_alloc_channel(int offset);
+void stm_free_channel(int channel);
+
+#endif /* __KERNEL__ */
+
+#endif /* STM_H */
--
1.7.3.1
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