Re: [RESEND PATCH V4 4/4] coresight-stm: adding driver for CoreSight STM component
From: Chunyan Zhang
Date: Sun Mar 27 2016 - 23:03:51 EST
On Fri, Mar 25, 2016 at 8:48 PM, Mathieu Poirier
<mathieu.poirier@xxxxxxxxxx> wrote:
> On 7 March 2016 at 23:33, Chunyan Zhang <zhang.chunyan@xxxxxxxxxx> wrote:
>> From: Pratik Patel <pratikp@xxxxxxxxxxxxxx>
>>
>> This driver adds support for the STM CoreSight IP block, allowing any
>> system compoment (HW or SW) to log and aggregate messages via a
>> single entity.
>>
>> The CoreSight STM exposes an application defined number of channels
>> called stimulus port. Configuration is done using entries in sysfs
>> and channels made available to userspace via configfs.
>>
>> Signed-off-by: Pratik Patel <pratikp@xxxxxxxxxxxxxx>
>> Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>> Signed-off-by: Chunyan Zhang <zhang.chunyan@xxxxxxxxxx>
>> ---
>> .../ABI/testing/sysfs-bus-coresight-devices-stm | 53 ++
>> Documentation/trace/coresight.txt | 37 +-
>> drivers/hwtracing/coresight/Kconfig | 11 +
>> drivers/hwtracing/coresight/Makefile | 1 +
>> drivers/hwtracing/coresight/coresight-stm.c | 890 +++++++++++++++++++++
>> include/linux/coresight-stm.h | 6 +
>> include/uapi/linux/coresight-stm.h | 21 +
>> 7 files changed, 1017 insertions(+), 2 deletions(-)
>> create mode 100644 Documentation/ABI/testing/sysfs-bus-coresight-devices-stm
>> create mode 100644 drivers/hwtracing/coresight/coresight-stm.c
>> create mode 100644 include/linux/coresight-stm.h
>> create mode 100644 include/uapi/linux/coresight-stm.h
>>
>> 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 0000000..c519056
>> --- /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: February 2016
>> +KernelVersion: 4.5
>> +Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>> +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.
>
> Please update the kernel version (4.7) and month.
OK.
>
>> +
>> +What: /sys/bus/coresight/devices/<memory_map>.stm/hwevent_enable
>> +Date: February 2016
>> +KernelVersion: 4.5
>> +Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>> +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: February 2016
>> +KernelVersion: 4.5
>> +Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>> +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: February 2016
>> +KernelVersion: 4.5
>> +Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>> +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: February 2016
>> +KernelVersion: 4.5
>> +Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>> +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: February 2016
>> +KernelVersion: 4.5
>> +Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>> +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: February 2016
>> +KernelVersion: 4.5
>> +Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>> +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 0a5c329..a33c88c 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 c85935f..f4a8bfa 100644
>> --- a/drivers/hwtracing/coresight/Kconfig
>> +++ b/drivers/hwtracing/coresight/Kconfig
>> @@ -77,4 +77,15 @@ 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 99f8e5f..1f6eaec 100644
>> --- a/drivers/hwtracing/coresight/Makefile
>> +++ b/drivers/hwtracing/coresight/Makefile
>> @@ -11,3 +11,4 @@ obj-$(CONFIG_CORESIGHT_LINKS_AND_SINKS) += coresight-funnel.o \
>> obj-$(CONFIG_CORESIGHT_SOURCE_ETM3X) += coresight-etm3x.o coresight-etm-cp14.o
>> obj-$(CONFIG_CORESIGHT_SOURCE_ETM4X) += coresight-etm4x.o
>> obj-$(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 0000000..6cc26dd
>> --- /dev/null
>> +++ b/drivers/hwtracing/coresight/coresight-stm.c
>> @@ -0,0 +1,890 @@
>> +/* Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
>> + *
>> + * 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@xxxxxxxxxxxxxx>
>> + *
>> + * Serious refactoring, code cleanup and upgrading to the Coresight upstream
>> + * framework by Mathieu Poirier
>> + * (C) 2015-2016 Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>> + *
>> + * Guaranteed timing and support for various packet type coming from the
>> + * generic STM API by Chunyan Zhang
>> + * (C) 2015-2016 Chunyan Zhang <zhang.chunyan@xxxxxxxxxx>
>> + */
>> +#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/module.h>
>> +#include <linux/of_address.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;
>> +
>> +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.
>> + * @enable: this STM is being used.
>> + * @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;
>> + bool enable;
>> + 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 stm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
>> +
>> + pm_runtime_get_sync(drvdata->dev);
>> +
>> + spin_lock(&drvdata->spinlock);
>> + stm_enable_hw(drvdata);
>> + drvdata->enable = true;
>> + 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);
>> +
>> + spin_lock(&drvdata->spinlock);
>> + stm_disable_hw(drvdata);
>> + drvdata->enable = false;
>> + spin_unlock(&drvdata->spinlock);
>> +
>> + /* Wait until the engine has completely stopped */
>> + coresight_timeout(drvdata, STMTCSR, STMTCSR_BUSY_BIT, 0);
>> +
>> + pm_runtime_put(drvdata->dev);
>> +
>> + 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
>
> I thought we agreed to remove this?
Ah, right, will remove this.
>
>> + 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 && drvdata->enable))
>> + 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 && drvdata->enable))
>> + 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 API set a size of zero on flag packets. */
>> + size = 1;
>> + stm_send((void *)ch_addr, payload, size, drvdata->write_bytes);
>> + size = 0;
>> + 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 (!drvdata->enable) {
>> + 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 (drvdata->enable) {
>> + 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 (!drvdata->enable) {
>> + 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 (drvdata->enable) {
>> + 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_simple_func(type, name, offset) \
>> +static ssize_t name##_show(struct device *_dev, \
>> + struct device_attribute *attr, char *buf) \
>> +{ \
>> + type *drvdata = dev_get_drvdata(_dev->parent); \
>> + return scnprintf(buf, PAGE_SIZE, "0x%08x\n", \
>> + readl_relaxed(drvdata->base + offset)); \
>> +} \
>> +DEVICE_ATTR_RO(name)
>
> A solution for this will appear in kernel 4.6-rc1. Please modify accordingly.
Ok.
>
>> +
>> +#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);
>> +
>> + return BMVAL(stmspfeat2r, 12, 15) ? 8 : 4;
>
> Please provide comments when using hard coded value like this. That
> way people understand what is happening without having to go back to
> the TRM.
Right, will add comments for this in the next version of patch.
Thanks for your review,
Chunyan
>
>> +}
>> +
>> +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;
>> +
>> + /*
>> + * Select arbitrary value to start with. If there is a conflict
>> + * with other tracers the framework will deal with it.
>> + */
>> + drvdata->traceid = 0x20;
>> +
>> + /* 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);
>> + drvdata->stm.mshared = 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,
>> + },
>> + .probe = stm_probe,
>> + .id_table = stm_ids,
>> +};
>> +
>> +module_amba_driver(stm_driver);
>> +
>> +MODULE_LICENSE("GPL v2");
>> +MODULE_DESCRIPTION("CoreSight System Trace Macrocell driver");
>> diff --git a/include/linux/coresight-stm.h b/include/linux/coresight-stm.h
>> new file mode 100644
>> index 0000000..a978bb8
>> --- /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 0000000..7e4272c
>> --- /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
>> --
>> 1.9.1
>>