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-rw-r--r--Documentation/ABI/testing/sysfs-bus-coresight-devices-stm53
-rw-r--r--Documentation/trace/coresight.txt37
-rw-r--r--drivers/hwtracing/coresight/Kconfig11
-rw-r--r--drivers/hwtracing/coresight/Makefile1
-rw-r--r--drivers/hwtracing/coresight/coresight-stm.c920
-rw-r--r--include/linux/coresight-stm.h6
-rw-r--r--include/uapi/linux/coresight-stm.h21
7 files changed, 1047 insertions, 2 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-stm b/Documentation/ABI/testing/sysfs-bus-coresight-devices-stm
new file mode 100644
index 000000000000..1dffabe7f48d
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-stm
@@ -0,0 +1,53 @@
+What: /sys/bus/coresight/devices/<memory_map>.stm/enable_source
+Date: April 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@linaro.org>
+Description: (RW) Enable/disable tracing on this specific trace macrocell.
+ Enabling the trace macrocell implies it has been configured
+ properly and a sink has been identified for it. The path
+ of coresight components linking the source to the sink is
+ configured and managed automatically by the coresight framework.
+
+What: /sys/bus/coresight/devices/<memory_map>.stm/hwevent_enable
+Date: April 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@linaro.org>
+Description: (RW) Provides access to the HW event enable register, used in
+ conjunction with HW event bank select register.
+
+What: /sys/bus/coresight/devices/<memory_map>.stm/hwevent_select
+Date: April 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@linaro.org>
+Description: (RW) Gives access to the HW event block select register
+ (STMHEBSR) in order to configure up to 256 channels. Used in
+ conjunction with "hwevent_enable" register as described above.
+
+What: /sys/bus/coresight/devices/<memory_map>.stm/port_enable
+Date: April 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@linaro.org>
+Description: (RW) Provides access to the stimulus port enable register
+ (STMSPER). Used in conjunction with "port_select" described
+ below.
+
+What: /sys/bus/coresight/devices/<memory_map>.stm/port_select
+Date: April 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@linaro.org>
+Description: (RW) Used to determine which bank of stimulus port bit in
+ register STMSPER (see above) apply to.
+
+What: /sys/bus/coresight/devices/<memory_map>.stm/status
+Date: April 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@linaro.org>
+Description: (R) List various control and status registers. The specific
+ layout and content is driver specific.
+
+What: /sys/bus/coresight/devices/<memory_map>.stm/traceid
+Date: April 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@linaro.org>
+Description: (RW) Holds the trace ID that will appear in the trace stream
+ coming from this trace entity.
diff --git a/Documentation/trace/coresight.txt b/Documentation/trace/coresight.txt
index 0a5c3290e732..a33c88cd5d1d 100644
--- a/Documentation/trace/coresight.txt
+++ b/Documentation/trace/coresight.txt
@@ -190,8 +190,8 @@ expected to be accessed and controlled using those entries.
Last but not least, "struct module *owner" is expected to be set to reflect
the information carried in "THIS_MODULE".
-How to use
-----------
+How to use the tracer modules
+-----------------------------
Before trace collection can start, a coresight sink needs to be identify.
There is no limit on the amount of sinks (nor sources) that can be enabled at
@@ -297,3 +297,36 @@ Info Tracing enabled
Instruction 13570831 0x8026B584 E28DD00C false ADD sp,sp,#0xc
Instruction 0 0x8026B588 E8BD8000 true LDM sp!,{pc}
Timestamp Timestamp: 17107041535
+
+How to use the STM module
+-------------------------
+
+Using the System Trace Macrocell module is the same as the tracers - the only
+difference is that clients are driving the trace capture rather
+than the program flow through the code.
+
+As with any other CoreSight component, specifics about the STM tracer can be
+found in sysfs with more information on each entry being found in [1]:
+
+root@genericarmv8:~# ls /sys/bus/coresight/devices/20100000.stm
+enable_source hwevent_select port_enable subsystem uevent
+hwevent_enable mgmt port_select traceid
+root@genericarmv8:~#
+
+Like any other source a sink needs to be identified and the STM enabled before
+being used:
+
+root@genericarmv8:~# echo 1 > /sys/bus/coresight/devices/20010000.etf/enable_sink
+root@genericarmv8:~# echo 1 > /sys/bus/coresight/devices/20100000.stm/enable_source
+
+From there user space applications can request and use channels using the devfs
+interface provided for that purpose by the generic STM API:
+
+root@genericarmv8:~# ls -l /dev/20100000.stm
+crw------- 1 root root 10, 61 Jan 3 18:11 /dev/20100000.stm
+root@genericarmv8:~#
+
+Details on how to use the generic STM API can be found here [2].
+
+[1]. Documentation/ABI/testing/sysfs-bus-coresight-devices-stm
+[2]. Documentation/trace/stm.txt
diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index db0541031c72..130cb2114059 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -78,4 +78,15 @@ config CORESIGHT_QCOM_REPLICATOR
programmable ATB replicator sends the ATB trace stream from the
ETB/ETF to the TPIUi and ETR.
+config CORESIGHT_STM
+ bool "CoreSight System Trace Macrocell driver"
+ depends on (ARM && !(CPU_32v3 || CPU_32v4 || CPU_32v4T)) || ARM64
+ select CORESIGHT_LINKS_AND_SINKS
+ select STM
+ help
+ This driver provides support for hardware assisted software
+ instrumentation based tracing. This is primarily used for
+ logging useful software events or data coming from various entities
+ in the system, possibly running different OSs
+
endif
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index 1d0e32c7dbe4..c6f84b57f52a 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile
@@ -13,3 +13,4 @@ obj-$(CONFIG_CORESIGHT_SOURCE_ETM3X) += coresight-etm3x.o coresight-etm-cp14.o \
obj-$(CONFIG_CORESIGHT_SOURCE_ETM4X) += coresight-etm4x.o \
coresight-etm4x-sysfs.o
obj-$(CONFIG_CORESIGHT_QCOM_REPLICATOR) += coresight-replicator-qcom.o
+obj-$(CONFIG_CORESIGHT_STM) += coresight-stm.o
diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c
new file mode 100644
index 000000000000..73be58a11e4f
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-stm.c
@@ -0,0 +1,920 @@
+/* Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
+ *
+ * Description: CoreSight System Trace Macrocell driver
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Initial implementation by Pratik Patel
+ * (C) 2014-2015 Pratik Patel <pratikp@codeaurora.org>
+ *
+ * Serious refactoring, code cleanup and upgrading to the Coresight upstream
+ * framework by Mathieu Poirier
+ * (C) 2015-2016 Mathieu Poirier <mathieu.poirier@linaro.org>
+ *
+ * Guaranteed timing and support for various packet type coming from the
+ * generic STM API by Chunyan Zhang
+ * (C) 2015-2016 Chunyan Zhang <zhang.chunyan@linaro.org>
+ */
+#include <asm/local.h>
+#include <linux/amba/bus.h>
+#include <linux/bitmap.h>
+#include <linux/clk.h>
+#include <linux/coresight.h>
+#include <linux/coresight-stm.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/moduleparam.h>
+#include <linux/of_address.h>
+#include <linux/perf_event.h>
+#include <linux/pm_runtime.h>
+#include <linux/stm.h>
+
+#include "coresight-priv.h"
+
+#define STMDMASTARTR 0xc04
+#define STMDMASTOPR 0xc08
+#define STMDMASTATR 0xc0c
+#define STMDMACTLR 0xc10
+#define STMDMAIDR 0xcfc
+#define STMHEER 0xd00
+#define STMHETER 0xd20
+#define STMHEBSR 0xd60
+#define STMHEMCR 0xd64
+#define STMHEMASTR 0xdf4
+#define STMHEFEAT1R 0xdf8
+#define STMHEIDR 0xdfc
+#define STMSPER 0xe00
+#define STMSPTER 0xe20
+#define STMPRIVMASKR 0xe40
+#define STMSPSCR 0xe60
+#define STMSPMSCR 0xe64
+#define STMSPOVERRIDER 0xe68
+#define STMSPMOVERRIDER 0xe6c
+#define STMSPTRIGCSR 0xe70
+#define STMTCSR 0xe80
+#define STMTSSTIMR 0xe84
+#define STMTSFREQR 0xe8c
+#define STMSYNCR 0xe90
+#define STMAUXCR 0xe94
+#define STMSPFEAT1R 0xea0
+#define STMSPFEAT2R 0xea4
+#define STMSPFEAT3R 0xea8
+#define STMITTRIGGER 0xee8
+#define STMITATBDATA0 0xeec
+#define STMITATBCTR2 0xef0
+#define STMITATBID 0xef4
+#define STMITATBCTR0 0xef8
+
+#define STM_32_CHANNEL 32
+#define BYTES_PER_CHANNEL 256
+#define STM_TRACE_BUF_SIZE 4096
+#define STM_SW_MASTER_END 127
+
+/* Register bit definition */
+#define STMTCSR_BUSY_BIT 23
+/* Reserve the first 10 channels for kernel usage */
+#define STM_CHANNEL_OFFSET 0
+
+enum stm_pkt_type {
+ STM_PKT_TYPE_DATA = 0x98,
+ STM_PKT_TYPE_FLAG = 0xE8,
+ STM_PKT_TYPE_TRIG = 0xF8,
+};
+
+#define stm_channel_addr(drvdata, ch) (drvdata->chs.base + \
+ (ch * BYTES_PER_CHANNEL))
+#define stm_channel_off(type, opts) (type & ~opts)
+
+static int boot_nr_channel;
+
+/*
+ * Not really modular but using module_param is the easiest way to
+ * remain consistent with existing use cases for now.
+ */
+module_param_named(
+ boot_nr_channel, boot_nr_channel, int, S_IRUGO
+);
+
+/**
+ * struct channel_space - central management entity for extended ports
+ * @base: memory mapped base address where channels start.
+ * @guaraneed: is the channel delivery guaranteed.
+ */
+struct channel_space {
+ void __iomem *base;
+ unsigned long *guaranteed;
+};
+
+/**
+ * struct stm_drvdata - specifics associated to an STM component
+ * @base: memory mapped base address for this component.
+ * @dev: the device entity associated to this component.
+ * @atclk: optional clock for the core parts of the STM.
+ * @csdev: component vitals needed by the framework.
+ * @spinlock: only one at a time pls.
+ * @chs: the channels accociated to this STM.
+ * @stm: structure associated to the generic STM interface.
+ * @mode: this tracer's mode, i.e sysFS, or disabled.
+ * @traceid: value of the current ID for this component.
+ * @write_bytes: Maximus bytes this STM can write at a time.
+ * @stmsper: settings for register STMSPER.
+ * @stmspscr: settings for register STMSPSCR.
+ * @numsp: the total number of stimulus port support by this STM.
+ * @stmheer: settings for register STMHEER.
+ * @stmheter: settings for register STMHETER.
+ * @stmhebsr: settings for register STMHEBSR.
+ */
+struct stm_drvdata {
+ void __iomem *base;
+ struct device *dev;
+ struct clk *atclk;
+ struct coresight_device *csdev;
+ spinlock_t spinlock;
+ struct channel_space chs;
+ struct stm_data stm;
+ local_t mode;
+ u8 traceid;
+ u32 write_bytes;
+ u32 stmsper;
+ u32 stmspscr;
+ u32 numsp;
+ u32 stmheer;
+ u32 stmheter;
+ u32 stmhebsr;
+};
+
+static void stm_hwevent_enable_hw(struct stm_drvdata *drvdata)
+{
+ CS_UNLOCK(drvdata->base);
+
+ writel_relaxed(drvdata->stmhebsr, drvdata->base + STMHEBSR);
+ writel_relaxed(drvdata->stmheter, drvdata->base + STMHETER);
+ writel_relaxed(drvdata->stmheer, drvdata->base + STMHEER);
+ writel_relaxed(0x01 | /* Enable HW event tracing */
+ 0x04, /* Error detection on event tracing */
+ drvdata->base + STMHEMCR);
+
+ CS_LOCK(drvdata->base);
+}
+
+static void stm_port_enable_hw(struct stm_drvdata *drvdata)
+{
+ CS_UNLOCK(drvdata->base);
+ /* ATB trigger enable on direct writes to TRIG locations */
+ writel_relaxed(0x10,
+ drvdata->base + STMSPTRIGCSR);
+ writel_relaxed(drvdata->stmspscr, drvdata->base + STMSPSCR);
+ writel_relaxed(drvdata->stmsper, drvdata->base + STMSPER);
+
+ CS_LOCK(drvdata->base);
+}
+
+static void stm_enable_hw(struct stm_drvdata *drvdata)
+{
+ if (drvdata->stmheer)
+ stm_hwevent_enable_hw(drvdata);
+
+ stm_port_enable_hw(drvdata);
+
+ CS_UNLOCK(drvdata->base);
+
+ /* 4096 byte between synchronisation packets */
+ writel_relaxed(0xFFF, drvdata->base + STMSYNCR);
+ writel_relaxed((drvdata->traceid << 16 | /* trace id */
+ 0x02 | /* timestamp enable */
+ 0x01), /* global STM enable */
+ drvdata->base + STMTCSR);
+
+ CS_LOCK(drvdata->base);
+}
+
+static int stm_enable(struct coresight_device *csdev,
+ struct perf_event_attr *attr, u32 mode)
+{
+ u32 val;
+ struct stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+
+ if (mode != CS_MODE_SYSFS)
+ return -EINVAL;
+
+ val = local_cmpxchg(&drvdata->mode, CS_MODE_DISABLED, mode);
+
+ /* Someone is already using the tracer */
+ if (val)
+ return -EBUSY;
+
+ pm_runtime_get_sync(drvdata->dev);
+
+ spin_lock(&drvdata->spinlock);
+ stm_enable_hw(drvdata);
+ spin_unlock(&drvdata->spinlock);
+
+ dev_info(drvdata->dev, "STM tracing enabled\n");
+ return 0;
+}
+
+static void stm_hwevent_disable_hw(struct stm_drvdata *drvdata)
+{
+ CS_UNLOCK(drvdata->base);
+
+ writel_relaxed(0x0, drvdata->base + STMHEMCR);
+ writel_relaxed(0x0, drvdata->base + STMHEER);
+ writel_relaxed(0x0, drvdata->base + STMHETER);
+
+ CS_LOCK(drvdata->base);
+}
+
+static void stm_port_disable_hw(struct stm_drvdata *drvdata)
+{
+ CS_UNLOCK(drvdata->base);
+
+ writel_relaxed(0x0, drvdata->base + STMSPER);
+ writel_relaxed(0x0, drvdata->base + STMSPTRIGCSR);
+
+ CS_LOCK(drvdata->base);
+}
+
+static void stm_disable_hw(struct stm_drvdata *drvdata)
+{
+ u32 val;
+
+ CS_UNLOCK(drvdata->base);
+
+ val = readl_relaxed(drvdata->base + STMTCSR);
+ val &= ~0x1; /* clear global STM enable [0] */
+ writel_relaxed(val, drvdata->base + STMTCSR);
+
+ CS_LOCK(drvdata->base);
+
+ stm_port_disable_hw(drvdata);
+ if (drvdata->stmheer)
+ stm_hwevent_disable_hw(drvdata);
+}
+
+static void stm_disable(struct coresight_device *csdev)
+{
+ struct stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+
+ /*
+ * For as long as the tracer isn't disabled another entity can't
+ * change its status. As such we can read the status here without
+ * fearing it will change under us.
+ */
+ if (local_read(&drvdata->mode) == CS_MODE_SYSFS) {
+ spin_lock(&drvdata->spinlock);
+ stm_disable_hw(drvdata);
+ spin_unlock(&drvdata->spinlock);
+
+ /* Wait until the engine has completely stopped */
+ coresight_timeout(drvdata, STMTCSR, STMTCSR_BUSY_BIT, 0);
+
+ pm_runtime_put(drvdata->dev);
+
+ local_set(&drvdata->mode, CS_MODE_DISABLED);
+ dev_info(drvdata->dev, "STM tracing disabled\n");
+ }
+}
+
+static int stm_trace_id(struct coresight_device *csdev)
+{
+ struct stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+
+ return drvdata->traceid;
+}
+
+static const struct coresight_ops_source stm_source_ops = {
+ .trace_id = stm_trace_id,
+ .enable = stm_enable,
+ .disable = stm_disable,
+};
+
+static const struct coresight_ops stm_cs_ops = {
+ .source_ops = &stm_source_ops,
+};
+
+static inline bool stm_addr_unaligned(const void *addr, u8 write_bytes)
+{
+ return ((unsigned long)addr & (write_bytes - 1));
+}
+
+static void stm_send(void *addr, const void *data, u32 size, u8 write_bytes)
+{
+ u8 paload[8];
+
+ if (stm_addr_unaligned(data, write_bytes)) {
+ memcpy(paload, data, size);
+ data = paload;
+ }
+
+ /* now we are 64bit/32bit aligned */
+ switch (size) {
+#ifdef CONFIG_64BIT
+ case 8:
+ writeq_relaxed(*(u64 *)data, addr);
+ break;
+#endif
+ case 4:
+ writel_relaxed(*(u32 *)data, addr);
+ break;
+ case 2:
+ writew_relaxed(*(u16 *)data, addr);
+ break;
+ case 1:
+ writeb_relaxed(*(u8 *)data, addr);
+ break;
+ default:
+ break;
+ }
+}
+
+static int stm_generic_link(struct stm_data *stm_data,
+ unsigned int master, unsigned int channel)
+{
+ struct stm_drvdata *drvdata = container_of(stm_data,
+ struct stm_drvdata, stm);
+ if (!drvdata || !drvdata->csdev)
+ return -EINVAL;
+
+ return coresight_enable(drvdata->csdev);
+}
+
+static void stm_generic_unlink(struct stm_data *stm_data,
+ unsigned int master, unsigned int channel)
+{
+ struct stm_drvdata *drvdata = container_of(stm_data,
+ struct stm_drvdata, stm);
+ if (!drvdata || !drvdata->csdev)
+ return;
+
+ stm_disable(drvdata->csdev);
+}
+
+static long stm_generic_set_options(struct stm_data *stm_data,
+ unsigned int master,
+ unsigned int channel,
+ unsigned int nr_chans,
+ unsigned long options)
+{
+ struct stm_drvdata *drvdata = container_of(stm_data,
+ struct stm_drvdata, stm);
+ if (!(drvdata && local_read(&drvdata->mode)))
+ return -EINVAL;
+
+ if (channel >= drvdata->numsp)
+ return -EINVAL;
+
+ switch (options) {
+ case STM_OPTION_GUARANTEED:
+ set_bit(channel, drvdata->chs.guaranteed);
+ break;
+
+ case STM_OPTION_INVARIANT:
+ clear_bit(channel, drvdata->chs.guaranteed);
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static ssize_t stm_generic_packet(struct stm_data *stm_data,
+ unsigned int master,
+ unsigned int channel,
+ unsigned int packet,
+ unsigned int flags,
+ unsigned int size,
+ const unsigned char *payload)
+{
+ unsigned long ch_addr;
+ struct stm_drvdata *drvdata = container_of(stm_data,
+ struct stm_drvdata, stm);
+
+ if (!(drvdata && local_read(&drvdata->mode)))
+ return 0;
+
+ if (channel >= drvdata->numsp)
+ return 0;
+
+ ch_addr = (unsigned long)stm_channel_addr(drvdata, channel);
+
+ flags = (flags == STP_PACKET_TIMESTAMPED) ? STM_FLAG_TIMESTAMPED : 0;
+ flags |= test_bit(channel, drvdata->chs.guaranteed) ?
+ STM_FLAG_GUARANTEED : 0;
+
+ if (size > drvdata->write_bytes)
+ size = drvdata->write_bytes;
+ else
+ size = rounddown_pow_of_two(size);
+
+ switch (packet) {
+ case STP_PACKET_FLAG:
+ ch_addr |= stm_channel_off(STM_PKT_TYPE_FLAG, flags);
+
+ /*
+ * The generic STM core sets a size of '0' on flag packets.
+ * As such send a flag packet of size '1' and tell the
+ * core we did so.
+ */
+ stm_send((void *)ch_addr, payload, 1, drvdata->write_bytes);
+ size = 1;
+ break;
+
+ case STP_PACKET_DATA:
+ ch_addr |= stm_channel_off(STM_PKT_TYPE_DATA, flags);
+ stm_send((void *)ch_addr, payload, size,
+ drvdata->write_bytes);
+ break;
+
+ default:
+ return -ENOTSUPP;
+ }
+
+ return size;
+}
+
+static ssize_t hwevent_enable_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ unsigned long val = drvdata->stmheer;
+
+ return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
+}
+
+static ssize_t hwevent_enable_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ unsigned long val;
+ int ret = 0;
+
+ ret = kstrtoul(buf, 16, &val);
+ if (ret)
+ return -EINVAL;
+
+ drvdata->stmheer = val;
+ /* HW event enable and trigger go hand in hand */
+ drvdata->stmheter = val;
+
+ return size;
+}
+static DEVICE_ATTR_RW(hwevent_enable);
+
+static ssize_t hwevent_select_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ unsigned long val = drvdata->stmhebsr;
+
+ return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
+}
+
+static ssize_t hwevent_select_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ unsigned long val;
+ int ret = 0;
+
+ ret = kstrtoul(buf, 16, &val);
+ if (ret)
+ return -EINVAL;
+
+ drvdata->stmhebsr = val;
+
+ return size;
+}
+static DEVICE_ATTR_RW(hwevent_select);
+
+static ssize_t port_select_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ unsigned long val;
+
+ if (!local_read(&drvdata->mode)) {
+ val = drvdata->stmspscr;
+ } else {
+ spin_lock(&drvdata->spinlock);
+ val = readl_relaxed(drvdata->base + STMSPSCR);
+ spin_unlock(&drvdata->spinlock);
+ }
+
+ return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
+}
+
+static ssize_t port_select_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ unsigned long val, stmsper;
+ int ret = 0;
+
+ ret = kstrtoul(buf, 16, &val);
+ if (ret)
+ return ret;
+
+ spin_lock(&drvdata->spinlock);
+ drvdata->stmspscr = val;
+
+ if (local_read(&drvdata->mode)) {
+ CS_UNLOCK(drvdata->base);
+ /* Process as per ARM's TRM recommendation */
+ stmsper = readl_relaxed(drvdata->base + STMSPER);
+ writel_relaxed(0x0, drvdata->base + STMSPER);
+ writel_relaxed(drvdata->stmspscr, drvdata->base + STMSPSCR);
+ writel_relaxed(stmsper, drvdata->base + STMSPER);
+ CS_LOCK(drvdata->base);
+ }
+ spin_unlock(&drvdata->spinlock);
+
+ return size;
+}
+static DEVICE_ATTR_RW(port_select);
+
+static ssize_t port_enable_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ unsigned long val;
+
+ if (!local_read(&drvdata->mode)) {
+ val = drvdata->stmsper;
+ } else {
+ spin_lock(&drvdata->spinlock);
+ val = readl_relaxed(drvdata->base + STMSPER);
+ spin_unlock(&drvdata->spinlock);
+ }
+
+ return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
+}
+
+static ssize_t port_enable_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ unsigned long val;
+ int ret = 0;
+
+ ret = kstrtoul(buf, 16, &val);
+ if (ret)
+ return ret;
+
+ spin_lock(&drvdata->spinlock);
+ drvdata->stmsper = val;
+
+ if (local_read(&drvdata->mode)) {
+ CS_UNLOCK(drvdata->base);
+ writel_relaxed(drvdata->stmsper, drvdata->base + STMSPER);
+ CS_LOCK(drvdata->base);
+ }
+ spin_unlock(&drvdata->spinlock);
+
+ return size;
+}
+static DEVICE_ATTR_RW(port_enable);
+
+static ssize_t traceid_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ unsigned long val;
+ struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ val = drvdata->traceid;
+ return sprintf(buf, "%#lx\n", val);
+}
+
+static ssize_t traceid_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ int ret;
+ unsigned long val;
+ struct stm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ ret = kstrtoul(buf, 16, &val);
+ if (ret)
+ return ret;
+
+ /* traceid field is 7bit wide on STM32 */
+ drvdata->traceid = val & 0x7f;
+ return size;
+}
+static DEVICE_ATTR_RW(traceid);
+
+#define coresight_stm_simple_func(name, offset) \
+ coresight_simple_func(struct stm_drvdata, name, offset)
+
+coresight_stm_simple_func(tcsr, STMTCSR);
+coresight_stm_simple_func(tsfreqr, STMTSFREQR);
+coresight_stm_simple_func(syncr, STMSYNCR);
+coresight_stm_simple_func(sper, STMSPER);
+coresight_stm_simple_func(spter, STMSPTER);
+coresight_stm_simple_func(privmaskr, STMPRIVMASKR);
+coresight_stm_simple_func(spscr, STMSPSCR);
+coresight_stm_simple_func(spmscr, STMSPMSCR);
+coresight_stm_simple_func(spfeat1r, STMSPFEAT1R);
+coresight_stm_simple_func(spfeat2r, STMSPFEAT2R);
+coresight_stm_simple_func(spfeat3r, STMSPFEAT3R);
+coresight_stm_simple_func(devid, CORESIGHT_DEVID);
+
+static struct attribute *coresight_stm_attrs[] = {
+ &dev_attr_hwevent_enable.attr,
+ &dev_attr_hwevent_select.attr,
+ &dev_attr_port_enable.attr,
+ &dev_attr_port_select.attr,
+ &dev_attr_traceid.attr,
+ NULL,
+};
+
+static struct attribute *coresight_stm_mgmt_attrs[] = {
+ &dev_attr_tcsr.attr,
+ &dev_attr_tsfreqr.attr,
+ &dev_attr_syncr.attr,
+ &dev_attr_sper.attr,
+ &dev_attr_spter.attr,
+ &dev_attr_privmaskr.attr,
+ &dev_attr_spscr.attr,
+ &dev_attr_spmscr.attr,
+ &dev_attr_spfeat1r.attr,
+ &dev_attr_spfeat2r.attr,
+ &dev_attr_spfeat3r.attr,
+ &dev_attr_devid.attr,
+ NULL,
+};
+
+static const struct attribute_group coresight_stm_group = {
+ .attrs = coresight_stm_attrs,
+};
+
+static const struct attribute_group coresight_stm_mgmt_group = {
+ .attrs = coresight_stm_mgmt_attrs,
+ .name = "mgmt",
+};
+
+static const struct attribute_group *coresight_stm_groups[] = {
+ &coresight_stm_group,
+ &coresight_stm_mgmt_group,
+ NULL,
+};
+
+static int stm_get_resource_byname(struct device_node *np,
+ char *ch_base, struct resource *res)
+{
+ const char *name = NULL;
+ int index = 0, found = 0;
+
+ while (!of_property_read_string_index(np, "reg-names", index, &name)) {
+ if (strcmp(ch_base, name)) {
+ index++;
+ continue;
+ }
+
+ /* We have a match and @index is where it's at */
+ found = 1;
+ break;
+ }
+
+ if (!found)
+ return -EINVAL;
+
+ return of_address_to_resource(np, index, res);
+}
+
+static u32 stm_fundamental_data_size(struct stm_drvdata *drvdata)
+{
+ u32 stmspfeat2r;
+
+ if (!IS_ENABLED(CONFIG_64BIT))
+ return 4;
+
+ stmspfeat2r = readl_relaxed(drvdata->base + STMSPFEAT2R);
+
+ /*
+ * bit[15:12] represents the fundamental data size
+ * 0 - 32-bit data
+ * 1 - 64-bit data
+ */
+ return BMVAL(stmspfeat2r, 12, 15) ? 8 : 4;
+}
+
+static u32 stm_num_stimulus_port(struct stm_drvdata *drvdata)
+{
+ u32 numsp;
+
+ numsp = readl_relaxed(drvdata->base + CORESIGHT_DEVID);
+ /*
+ * NUMPS in STMDEVID is 17 bit long and if equal to 0x0,
+ * 32 stimulus ports are supported.
+ */
+ numsp &= 0x1ffff;
+ if (!numsp)
+ numsp = STM_32_CHANNEL;
+ return numsp;
+}
+
+static void stm_init_default_data(struct stm_drvdata *drvdata)
+{
+ /* Don't use port selection */
+ drvdata->stmspscr = 0x0;
+ /*
+ * Enable all channel regardless of their number. When port
+ * selection isn't used (see above) STMSPER applies to all
+ * 32 channel group available, hence setting all 32 bits to 1
+ */
+ drvdata->stmsper = ~0x0;
+
+ /*
+ * The trace ID value for *ETM* tracers start at CPU_ID * 2 + 0x10 and
+ * anything equal to or higher than 0x70 is reserved. Since 0x00 is
+ * also reserved the STM trace ID needs to be higher than 0x00 and
+ * lowner than 0x10.
+ */
+ drvdata->traceid = 0x1;
+
+ /* Set invariant transaction timing on all channels */
+ bitmap_clear(drvdata->chs.guaranteed, 0, drvdata->numsp);
+}
+
+static void stm_init_generic_data(struct stm_drvdata *drvdata)
+{
+ drvdata->stm.name = dev_name(drvdata->dev);
+
+ /*
+ * MasterIDs are assigned at HW design phase. As such the core is
+ * using a single master for interaction with this device.
+ */
+ drvdata->stm.sw_start = 1;
+ drvdata->stm.sw_end = 1;
+ drvdata->stm.hw_override = true;
+ drvdata->stm.sw_nchannels = drvdata->numsp;
+ drvdata->stm.packet = stm_generic_packet;
+ drvdata->stm.link = stm_generic_link;
+ drvdata->stm.unlink = stm_generic_unlink;
+ drvdata->stm.set_options = stm_generic_set_options;
+}
+
+static int stm_probe(struct amba_device *adev, const struct amba_id *id)
+{
+ int ret;
+ void __iomem *base;
+ unsigned long *guaranteed;
+ struct device *dev = &adev->dev;
+ struct coresight_platform_data *pdata = NULL;
+ struct stm_drvdata *drvdata;
+ struct resource *res = &adev->res;
+ struct resource ch_res;
+ size_t res_size, bitmap_size;
+ struct coresight_desc *desc;
+ struct device_node *np = adev->dev.of_node;
+
+ if (np) {
+ pdata = of_get_coresight_platform_data(dev, np);
+ if (IS_ERR(pdata))
+ return PTR_ERR(pdata);
+ adev->dev.platform_data = pdata;
+ }
+ drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
+ if (!drvdata)
+ return -ENOMEM;
+
+ drvdata->dev = &adev->dev;
+ drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */
+ if (!IS_ERR(drvdata->atclk)) {
+ ret = clk_prepare_enable(drvdata->atclk);
+ if (ret)
+ return ret;
+ }
+ dev_set_drvdata(dev, drvdata);
+
+ base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+ drvdata->base = base;
+
+ ret = stm_get_resource_byname(np, "stm-stimulus-base", &ch_res);
+ if (ret)
+ return ret;
+
+ base = devm_ioremap_resource(dev, &ch_res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+ drvdata->chs.base = base;
+
+ drvdata->write_bytes = stm_fundamental_data_size(drvdata);
+
+ if (boot_nr_channel) {
+ drvdata->numsp = boot_nr_channel;
+ res_size = min((resource_size_t)(boot_nr_channel *
+ BYTES_PER_CHANNEL), resource_size(res));
+ } else {
+ drvdata->numsp = stm_num_stimulus_port(drvdata);
+ res_size = min((resource_size_t)(drvdata->numsp *
+ BYTES_PER_CHANNEL), resource_size(res));
+ }
+ bitmap_size = BITS_TO_LONGS(drvdata->numsp) * sizeof(long);
+
+ guaranteed = devm_kzalloc(dev, bitmap_size, GFP_KERNEL);
+ if (!guaranteed)
+ return -ENOMEM;
+ drvdata->chs.guaranteed = guaranteed;
+
+ spin_lock_init(&drvdata->spinlock);
+
+ stm_init_default_data(drvdata);
+ stm_init_generic_data(drvdata);
+
+ if (stm_register_device(dev, &drvdata->stm, THIS_MODULE)) {
+ dev_info(dev,
+ "stm_register_device failed, probing deffered\n");
+ return -EPROBE_DEFER;
+ }
+
+ desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
+ if (!desc) {
+ ret = -ENOMEM;
+ goto stm_unregister;
+ }
+
+ desc->type = CORESIGHT_DEV_TYPE_SOURCE;
+ desc->subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE;
+ desc->ops = &stm_cs_ops;
+ desc->pdata = pdata;
+ desc->dev = dev;
+ desc->groups = coresight_stm_groups;
+ drvdata->csdev = coresight_register(desc);
+ if (IS_ERR(drvdata->csdev)) {
+ ret = PTR_ERR(drvdata->csdev);
+ goto stm_unregister;
+ }
+
+ pm_runtime_put(&adev->dev);
+
+ dev_info(dev, "%s initialized\n", (char *)id->data);
+ return 0;
+
+stm_unregister:
+ stm_unregister_device(&drvdata->stm);
+ return ret;
+}
+
+#ifdef CONFIG_PM
+static int stm_runtime_suspend(struct device *dev)
+{
+ struct stm_drvdata *drvdata = dev_get_drvdata(dev);
+
+ if (drvdata && !IS_ERR(drvdata->atclk))
+ clk_disable_unprepare(drvdata->atclk);
+
+ return 0;
+}
+
+static int stm_runtime_resume(struct device *dev)
+{
+ struct stm_drvdata *drvdata = dev_get_drvdata(dev);
+
+ if (drvdata && !IS_ERR(drvdata->atclk))
+ clk_prepare_enable(drvdata->atclk);
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops stm_dev_pm_ops = {
+ SET_RUNTIME_PM_OPS(stm_runtime_suspend, stm_runtime_resume, NULL)
+};
+
+static struct amba_id stm_ids[] = {
+ {
+ .id = 0x0003b962,
+ .mask = 0x0003ffff,
+ .data = "STM32",
+ },
+ { 0, 0},
+};
+
+static struct amba_driver stm_driver = {
+ .drv = {
+ .name = "coresight-stm",
+ .owner = THIS_MODULE,
+ .pm = &stm_dev_pm_ops,
+ .suppress_bind_attrs = true,
+ },
+ .probe = stm_probe,
+ .id_table = stm_ids,
+};
+
+builtin_amba_driver(stm_driver);
diff --git a/include/linux/coresight-stm.h b/include/linux/coresight-stm.h
new file mode 100644
index 000000000000..a978bb85599a
--- /dev/null
+++ b/include/linux/coresight-stm.h
@@ -0,0 +1,6 @@
+#ifndef __LINUX_CORESIGHT_STM_H_
+#define __LINUX_CORESIGHT_STM_H_
+
+#include <uapi/linux/coresight-stm.h>
+
+#endif
diff --git a/include/uapi/linux/coresight-stm.h b/include/uapi/linux/coresight-stm.h
new file mode 100644
index 000000000000..7e4272cf1fb2
--- /dev/null
+++ b/include/uapi/linux/coresight-stm.h
@@ -0,0 +1,21 @@
+#ifndef __UAPI_CORESIGHT_STM_H_
+#define __UAPI_CORESIGHT_STM_H_
+
+#define STM_FLAG_TIMESTAMPED BIT(3)
+#define STM_FLAG_GUARANTEED BIT(7)
+
+/*
+ * The CoreSight STM supports guaranteed and invariant timing
+ * transactions. Guaranteed transactions are guaranteed to be
+ * traced, this might involve stalling the bus or system to
+ * ensure the transaction is accepted by the STM. While invariant
+ * timing transactions are not guaranteed to be traced, they
+ * will take an invariant amount of time regardless of the
+ * state of the STM.
+ */
+enum {
+ STM_OPTION_GUARANTEED = 0,
+ STM_OPTION_INVARIANT,
+};
+
+#endif