linux/drivers/hwtracing/coresight/coresight-etm3x-core.c
James Clark 5ad628a761 coresight: Use per-sink trace ID maps for Perf sessions
This will allow sessions with more than CORESIGHT_TRACE_IDS_MAX ETMs
as long as there are fewer than that many ETMs connected to each sink.

Each sink owns its own trace ID map, and any Perf session connecting to
that sink will allocate from it, even if the sink is currently in use by
other users. This is similar to the existing behavior where the dynamic
trace IDs are constant as long as there is any concurrent Perf session
active. It's not completely optimal because slightly more IDs will be
used than necessary, but the optimal solution involves tracking the PIDs
of each session and allocating ID maps based on the session owner. This
is difficult to do with the combination of per-thread and per-cpu modes
and some scheduling issues. The complexity of this isn't likely to worth
it because even with multiple users they'd just see a difference in the
ordering of ID allocations rather than hitting any limits (unless the
hardware does have too many ETMs connected to one sink).

Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: James Clark <james.clark@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20240722101202.26915-15-james.clark@linaro.org
2024-08-20 15:02:38 +01:00

1052 lines
26 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2011-2012, The Linux Foundation. All rights reserved.
*
* Description: CoreSight Program Flow Trace driver
*/
#include <linux/kernel.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/err.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/smp.h>
#include <linux/sysfs.h>
#include <linux/stat.h>
#include <linux/pm_runtime.h>
#include <linux/cpu.h>
#include <linux/of.h>
#include <linux/coresight.h>
#include <linux/coresight-pmu.h>
#include <linux/amba/bus.h>
#include <linux/seq_file.h>
#include <linux/uaccess.h>
#include <linux/clk.h>
#include <linux/perf_event.h>
#include <asm/sections.h>
#include "coresight-etm.h"
#include "coresight-etm-perf.h"
#include "coresight-trace-id.h"
/*
* Not really modular but using module_param is the easiest way to
* remain consistent with existing use cases for now.
*/
static int boot_enable;
module_param_named(boot_enable, boot_enable, int, S_IRUGO);
static struct etm_drvdata *etmdrvdata[NR_CPUS];
static enum cpuhp_state hp_online;
/*
* Memory mapped writes to clear os lock are not supported on some processors
* and OS lock must be unlocked before any memory mapped access on such
* processors, otherwise memory mapped reads/writes will be invalid.
*/
static void etm_os_unlock(struct etm_drvdata *drvdata)
{
/* Writing any value to ETMOSLAR unlocks the trace registers */
etm_writel(drvdata, 0x0, ETMOSLAR);
drvdata->os_unlock = true;
isb();
}
static void etm_set_pwrdwn(struct etm_drvdata *drvdata)
{
u32 etmcr;
/* Ensure pending cp14 accesses complete before setting pwrdwn */
mb();
isb();
etmcr = etm_readl(drvdata, ETMCR);
etmcr |= ETMCR_PWD_DWN;
etm_writel(drvdata, etmcr, ETMCR);
}
static void etm_clr_pwrdwn(struct etm_drvdata *drvdata)
{
u32 etmcr;
etmcr = etm_readl(drvdata, ETMCR);
etmcr &= ~ETMCR_PWD_DWN;
etm_writel(drvdata, etmcr, ETMCR);
/* Ensure pwrup completes before subsequent cp14 accesses */
mb();
isb();
}
static void etm_set_pwrup(struct etm_drvdata *drvdata)
{
u32 etmpdcr;
etmpdcr = readl_relaxed(drvdata->base + ETMPDCR);
etmpdcr |= ETMPDCR_PWD_UP;
writel_relaxed(etmpdcr, drvdata->base + ETMPDCR);
/* Ensure pwrup completes before subsequent cp14 accesses */
mb();
isb();
}
static void etm_clr_pwrup(struct etm_drvdata *drvdata)
{
u32 etmpdcr;
/* Ensure pending cp14 accesses complete before clearing pwrup */
mb();
isb();
etmpdcr = readl_relaxed(drvdata->base + ETMPDCR);
etmpdcr &= ~ETMPDCR_PWD_UP;
writel_relaxed(etmpdcr, drvdata->base + ETMPDCR);
}
/**
* coresight_timeout_etm - loop until a bit has changed to a specific state.
* @drvdata: etm's private data structure.
* @offset: address of a register, starting from @addr.
* @position: the position of the bit of interest.
* @value: the value the bit should have.
*
* Basically the same as @coresight_timeout except for the register access
* method where we have to account for CP14 configurations.
*
* Return: 0 as soon as the bit has taken the desired state or -EAGAIN if
* TIMEOUT_US has elapsed, which ever happens first.
*/
static int coresight_timeout_etm(struct etm_drvdata *drvdata, u32 offset,
int position, int value)
{
int i;
u32 val;
for (i = TIMEOUT_US; i > 0; i--) {
val = etm_readl(drvdata, offset);
/* Waiting on the bit to go from 0 to 1 */
if (value) {
if (val & BIT(position))
return 0;
/* Waiting on the bit to go from 1 to 0 */
} else {
if (!(val & BIT(position)))
return 0;
}
/*
* Delay is arbitrary - the specification doesn't say how long
* we are expected to wait. Extra check required to make sure
* we don't wait needlessly on the last iteration.
*/
if (i - 1)
udelay(1);
}
return -EAGAIN;
}
static void etm_set_prog(struct etm_drvdata *drvdata)
{
u32 etmcr;
etmcr = etm_readl(drvdata, ETMCR);
etmcr |= ETMCR_ETM_PRG;
etm_writel(drvdata, etmcr, ETMCR);
/*
* Recommended by spec for cp14 accesses to ensure etmcr write is
* complete before polling etmsr
*/
isb();
if (coresight_timeout_etm(drvdata, ETMSR, ETMSR_PROG_BIT, 1)) {
dev_err(&drvdata->csdev->dev,
"%s: timeout observed when probing at offset %#x\n",
__func__, ETMSR);
}
}
static void etm_clr_prog(struct etm_drvdata *drvdata)
{
u32 etmcr;
etmcr = etm_readl(drvdata, ETMCR);
etmcr &= ~ETMCR_ETM_PRG;
etm_writel(drvdata, etmcr, ETMCR);
/*
* Recommended by spec for cp14 accesses to ensure etmcr write is
* complete before polling etmsr
*/
isb();
if (coresight_timeout_etm(drvdata, ETMSR, ETMSR_PROG_BIT, 0)) {
dev_err(&drvdata->csdev->dev,
"%s: timeout observed when probing at offset %#x\n",
__func__, ETMSR);
}
}
void etm_set_default(struct etm_config *config)
{
int i;
if (WARN_ON_ONCE(!config))
return;
/*
* Taken verbatim from the TRM:
*
* To trace all memory:
* set bit [24] in register 0x009, the ETMTECR1, to 1
* set all other bits in register 0x009, the ETMTECR1, to 0
* set all bits in register 0x007, the ETMTECR2, to 0
* set register 0x008, the ETMTEEVR, to 0x6F (TRUE).
*/
config->enable_ctrl1 = ETMTECR1_INC_EXC;
config->enable_ctrl2 = 0x0;
config->enable_event = ETM_HARD_WIRE_RES_A;
config->trigger_event = ETM_DEFAULT_EVENT_VAL;
config->enable_event = ETM_HARD_WIRE_RES_A;
config->seq_12_event = ETM_DEFAULT_EVENT_VAL;
config->seq_21_event = ETM_DEFAULT_EVENT_VAL;
config->seq_23_event = ETM_DEFAULT_EVENT_VAL;
config->seq_31_event = ETM_DEFAULT_EVENT_VAL;
config->seq_32_event = ETM_DEFAULT_EVENT_VAL;
config->seq_13_event = ETM_DEFAULT_EVENT_VAL;
config->timestamp_event = ETM_DEFAULT_EVENT_VAL;
for (i = 0; i < ETM_MAX_CNTR; i++) {
config->cntr_rld_val[i] = 0x0;
config->cntr_event[i] = ETM_DEFAULT_EVENT_VAL;
config->cntr_rld_event[i] = ETM_DEFAULT_EVENT_VAL;
config->cntr_val[i] = 0x0;
}
config->seq_curr_state = 0x0;
config->ctxid_idx = 0x0;
for (i = 0; i < ETM_MAX_CTXID_CMP; i++)
config->ctxid_pid[i] = 0x0;
config->ctxid_mask = 0x0;
/* Setting default to 1024 as per TRM recommendation */
config->sync_freq = 0x400;
}
void etm_config_trace_mode(struct etm_config *config)
{
u32 flags, mode;
mode = config->mode;
mode &= (ETM_MODE_EXCL_KERN | ETM_MODE_EXCL_USER);
/* excluding kernel AND user space doesn't make sense */
if (mode == (ETM_MODE_EXCL_KERN | ETM_MODE_EXCL_USER))
return;
/* nothing to do if neither flags are set */
if (!(mode & ETM_MODE_EXCL_KERN) && !(mode & ETM_MODE_EXCL_USER))
return;
flags = (1 << 0 | /* instruction execute */
3 << 3 | /* ARM instruction */
0 << 5 | /* No data value comparison */
0 << 7 | /* No exact mach */
0 << 8); /* Ignore context ID */
/* No need to worry about single address comparators. */
config->enable_ctrl2 = 0x0;
/* Bit 0 is address range comparator 1 */
config->enable_ctrl1 = ETMTECR1_ADDR_COMP_1;
/*
* On ETMv3.5:
* ETMACTRn[13,11] == Non-secure state comparison control
* ETMACTRn[12,10] == Secure state comparison control
*
* b00 == Match in all modes in this state
* b01 == Do not match in any more in this state
* b10 == Match in all modes excepts user mode in this state
* b11 == Match only in user mode in this state
*/
/* Tracing in secure mode is not supported at this time */
flags |= (0 << 12 | 1 << 10);
if (mode & ETM_MODE_EXCL_USER) {
/* exclude user, match all modes except user mode */
flags |= (1 << 13 | 0 << 11);
} else {
/* exclude kernel, match only in user mode */
flags |= (1 << 13 | 1 << 11);
}
/*
* The ETMEEVR register is already set to "hard wire A". As such
* all there is to do is setup an address comparator that spans
* the entire address range and configure the state and mode bits.
*/
config->addr_val[0] = (u32) 0x0;
config->addr_val[1] = (u32) ~0x0;
config->addr_acctype[0] = flags;
config->addr_acctype[1] = flags;
config->addr_type[0] = ETM_ADDR_TYPE_RANGE;
config->addr_type[1] = ETM_ADDR_TYPE_RANGE;
}
#define ETM3X_SUPPORTED_OPTIONS (ETMCR_CYC_ACC | \
ETMCR_TIMESTAMP_EN | \
ETMCR_RETURN_STACK)
static int etm_parse_event_config(struct etm_drvdata *drvdata,
struct perf_event *event)
{
struct etm_config *config = &drvdata->config;
struct perf_event_attr *attr = &event->attr;
if (!attr)
return -EINVAL;
/* Clear configuration from previous run */
memset(config, 0, sizeof(struct etm_config));
if (attr->exclude_kernel)
config->mode = ETM_MODE_EXCL_KERN;
if (attr->exclude_user)
config->mode = ETM_MODE_EXCL_USER;
/* Always start from the default config */
etm_set_default(config);
/*
* By default the tracers are configured to trace the whole address
* range. Narrow the field only if requested by user space.
*/
if (config->mode)
etm_config_trace_mode(config);
/*
* At this time only cycle accurate, return stack and timestamp
* options are available.
*/
if (attr->config & ~ETM3X_SUPPORTED_OPTIONS)
return -EINVAL;
config->ctrl = attr->config;
/* Don't trace contextID when runs in non-root PID namespace */
if (!task_is_in_init_pid_ns(current))
config->ctrl &= ~ETMCR_CTXID_SIZE;
/*
* Possible to have cores with PTM (supports ret stack) and ETM
* (never has ret stack) on the same SoC. So if we have a request
* for return stack that can't be honoured on this core then
* clear the bit - trace will still continue normally
*/
if ((config->ctrl & ETMCR_RETURN_STACK) &&
!(drvdata->etmccer & ETMCCER_RETSTACK))
config->ctrl &= ~ETMCR_RETURN_STACK;
return 0;
}
static int etm_enable_hw(struct etm_drvdata *drvdata)
{
int i, rc;
u32 etmcr;
struct etm_config *config = &drvdata->config;
struct coresight_device *csdev = drvdata->csdev;
CS_UNLOCK(drvdata->base);
rc = coresight_claim_device_unlocked(csdev);
if (rc)
goto done;
/* Turn engine on */
etm_clr_pwrdwn(drvdata);
/* Apply power to trace registers */
etm_set_pwrup(drvdata);
/* Make sure all registers are accessible */
etm_os_unlock(drvdata);
etm_set_prog(drvdata);
etmcr = etm_readl(drvdata, ETMCR);
/* Clear setting from a previous run if need be */
etmcr &= ~ETM3X_SUPPORTED_OPTIONS;
etmcr |= drvdata->port_size;
etmcr |= ETMCR_ETM_EN;
etm_writel(drvdata, config->ctrl | etmcr, ETMCR);
etm_writel(drvdata, config->trigger_event, ETMTRIGGER);
etm_writel(drvdata, config->startstop_ctrl, ETMTSSCR);
etm_writel(drvdata, config->enable_event, ETMTEEVR);
etm_writel(drvdata, config->enable_ctrl1, ETMTECR1);
etm_writel(drvdata, config->fifofull_level, ETMFFLR);
for (i = 0; i < drvdata->nr_addr_cmp; i++) {
etm_writel(drvdata, config->addr_val[i], ETMACVRn(i));
etm_writel(drvdata, config->addr_acctype[i], ETMACTRn(i));
}
for (i = 0; i < drvdata->nr_cntr; i++) {
etm_writel(drvdata, config->cntr_rld_val[i], ETMCNTRLDVRn(i));
etm_writel(drvdata, config->cntr_event[i], ETMCNTENRn(i));
etm_writel(drvdata, config->cntr_rld_event[i],
ETMCNTRLDEVRn(i));
etm_writel(drvdata, config->cntr_val[i], ETMCNTVRn(i));
}
etm_writel(drvdata, config->seq_12_event, ETMSQ12EVR);
etm_writel(drvdata, config->seq_21_event, ETMSQ21EVR);
etm_writel(drvdata, config->seq_23_event, ETMSQ23EVR);
etm_writel(drvdata, config->seq_31_event, ETMSQ31EVR);
etm_writel(drvdata, config->seq_32_event, ETMSQ32EVR);
etm_writel(drvdata, config->seq_13_event, ETMSQ13EVR);
etm_writel(drvdata, config->seq_curr_state, ETMSQR);
for (i = 0; i < drvdata->nr_ext_out; i++)
etm_writel(drvdata, ETM_DEFAULT_EVENT_VAL, ETMEXTOUTEVRn(i));
for (i = 0; i < drvdata->nr_ctxid_cmp; i++)
etm_writel(drvdata, config->ctxid_pid[i], ETMCIDCVRn(i));
etm_writel(drvdata, config->ctxid_mask, ETMCIDCMR);
etm_writel(drvdata, config->sync_freq, ETMSYNCFR);
/* No external input selected */
etm_writel(drvdata, 0x0, ETMEXTINSELR);
etm_writel(drvdata, config->timestamp_event, ETMTSEVR);
/* No auxiliary control selected */
etm_writel(drvdata, 0x0, ETMAUXCR);
etm_writel(drvdata, drvdata->traceid, ETMTRACEIDR);
/* No VMID comparator value selected */
etm_writel(drvdata, 0x0, ETMVMIDCVR);
etm_clr_prog(drvdata);
done:
CS_LOCK(drvdata->base);
dev_dbg(&drvdata->csdev->dev, "cpu: %d enable smp call done: %d\n",
drvdata->cpu, rc);
return rc;
}
struct etm_enable_arg {
struct etm_drvdata *drvdata;
int rc;
};
static void etm_enable_hw_smp_call(void *info)
{
struct etm_enable_arg *arg = info;
if (WARN_ON(!arg))
return;
arg->rc = etm_enable_hw(arg->drvdata);
}
static int etm_cpu_id(struct coresight_device *csdev)
{
struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
return drvdata->cpu;
}
int etm_read_alloc_trace_id(struct etm_drvdata *drvdata)
{
int trace_id;
/*
* This will allocate a trace ID to the cpu,
* or return the one currently allocated.
*
* trace id function has its own lock
*/
trace_id = coresight_trace_id_get_cpu_id(drvdata->cpu);
if (IS_VALID_CS_TRACE_ID(trace_id))
drvdata->traceid = (u8)trace_id;
else
dev_err(&drvdata->csdev->dev,
"Failed to allocate trace ID for %s on CPU%d\n",
dev_name(&drvdata->csdev->dev), drvdata->cpu);
return trace_id;
}
void etm_release_trace_id(struct etm_drvdata *drvdata)
{
coresight_trace_id_put_cpu_id(drvdata->cpu);
}
static int etm_enable_perf(struct coresight_device *csdev,
struct perf_event *event,
struct coresight_trace_id_map *id_map)
{
struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
int trace_id;
if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id()))
return -EINVAL;
/* Configure the tracer based on the session's specifics */
etm_parse_event_config(drvdata, event);
/*
* perf allocates cpu ids as part of _setup_aux() - device needs to use
* the allocated ID. This reads the current version without allocation.
*
* This does not use the trace id lock to prevent lock_dep issues
* with perf locks - we know the ID cannot change until perf shuts down
* the session
*/
trace_id = coresight_trace_id_read_cpu_id_map(drvdata->cpu, id_map);
if (!IS_VALID_CS_TRACE_ID(trace_id)) {
dev_err(&drvdata->csdev->dev, "Failed to set trace ID for %s on CPU%d\n",
dev_name(&drvdata->csdev->dev), drvdata->cpu);
return -EINVAL;
}
drvdata->traceid = (u8)trace_id;
/* And enable it */
return etm_enable_hw(drvdata);
}
static int etm_enable_sysfs(struct coresight_device *csdev)
{
struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
struct etm_enable_arg arg = { };
int ret;
spin_lock(&drvdata->spinlock);
/* sysfs needs to allocate and set a trace ID */
ret = etm_read_alloc_trace_id(drvdata);
if (ret < 0)
goto unlock_enable_sysfs;
/*
* Configure the ETM only if the CPU is online. If it isn't online
* hw configuration will take place on the local CPU during bring up.
*/
if (cpu_online(drvdata->cpu)) {
arg.drvdata = drvdata;
ret = smp_call_function_single(drvdata->cpu,
etm_enable_hw_smp_call, &arg, 1);
if (!ret)
ret = arg.rc;
if (!ret)
drvdata->sticky_enable = true;
} else {
ret = -ENODEV;
}
if (ret)
etm_release_trace_id(drvdata);
unlock_enable_sysfs:
spin_unlock(&drvdata->spinlock);
if (!ret)
dev_dbg(&csdev->dev, "ETM tracing enabled\n");
return ret;
}
static int etm_enable(struct coresight_device *csdev, struct perf_event *event,
enum cs_mode mode, struct coresight_trace_id_map *id_map)
{
int ret;
struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
if (!coresight_take_mode(csdev, mode)) {
/* Someone is already using the tracer */
return -EBUSY;
}
switch (mode) {
case CS_MODE_SYSFS:
ret = etm_enable_sysfs(csdev);
break;
case CS_MODE_PERF:
ret = etm_enable_perf(csdev, event, id_map);
break;
default:
ret = -EINVAL;
}
/* The tracer didn't start */
if (ret)
coresight_set_mode(drvdata->csdev, CS_MODE_DISABLED);
return ret;
}
static void etm_disable_hw(void *info)
{
int i;
struct etm_drvdata *drvdata = info;
struct etm_config *config = &drvdata->config;
struct coresight_device *csdev = drvdata->csdev;
CS_UNLOCK(drvdata->base);
etm_set_prog(drvdata);
/* Read back sequencer and counters for post trace analysis */
config->seq_curr_state = (etm_readl(drvdata, ETMSQR) & ETM_SQR_MASK);
for (i = 0; i < drvdata->nr_cntr; i++)
config->cntr_val[i] = etm_readl(drvdata, ETMCNTVRn(i));
etm_set_pwrdwn(drvdata);
coresight_disclaim_device_unlocked(csdev);
CS_LOCK(drvdata->base);
dev_dbg(&drvdata->csdev->dev,
"cpu: %d disable smp call done\n", drvdata->cpu);
}
static void etm_disable_perf(struct coresight_device *csdev)
{
struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id()))
return;
CS_UNLOCK(drvdata->base);
/* Setting the prog bit disables tracing immediately */
etm_set_prog(drvdata);
/*
* There is no way to know when the tracer will be used again so
* power down the tracer.
*/
etm_set_pwrdwn(drvdata);
coresight_disclaim_device_unlocked(csdev);
CS_LOCK(drvdata->base);
/*
* perf will release trace ids when _free_aux()
* is called at the end of the session
*/
}
static void etm_disable_sysfs(struct coresight_device *csdev)
{
struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
/*
* Taking hotplug lock here protects from clocks getting disabled
* with tracing being left on (crash scenario) if user disable occurs
* after cpu online mask indicates the cpu is offline but before the
* DYING hotplug callback is serviced by the ETM driver.
*/
cpus_read_lock();
spin_lock(&drvdata->spinlock);
/*
* Executing etm_disable_hw on the cpu whose ETM is being disabled
* ensures that register writes occur when cpu is powered.
*/
smp_call_function_single(drvdata->cpu, etm_disable_hw, drvdata, 1);
spin_unlock(&drvdata->spinlock);
cpus_read_unlock();
/*
* we only release trace IDs when resetting sysfs.
* This permits sysfs users to read the trace ID after the trace
* session has completed. This maintains operational behaviour with
* prior trace id allocation method
*/
dev_dbg(&csdev->dev, "ETM tracing disabled\n");
}
static void etm_disable(struct coresight_device *csdev,
struct perf_event *event)
{
enum cs_mode mode;
/*
* 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.
*/
mode = coresight_get_mode(csdev);
switch (mode) {
case CS_MODE_DISABLED:
break;
case CS_MODE_SYSFS:
etm_disable_sysfs(csdev);
break;
case CS_MODE_PERF:
etm_disable_perf(csdev);
break;
default:
WARN_ON_ONCE(mode);
return;
}
if (mode)
coresight_set_mode(csdev, CS_MODE_DISABLED);
}
static const struct coresight_ops_source etm_source_ops = {
.cpu_id = etm_cpu_id,
.enable = etm_enable,
.disable = etm_disable,
};
static const struct coresight_ops etm_cs_ops = {
.source_ops = &etm_source_ops,
};
static int etm_online_cpu(unsigned int cpu)
{
if (!etmdrvdata[cpu])
return 0;
if (etmdrvdata[cpu]->boot_enable && !etmdrvdata[cpu]->sticky_enable)
coresight_enable_sysfs(etmdrvdata[cpu]->csdev);
return 0;
}
static int etm_starting_cpu(unsigned int cpu)
{
if (!etmdrvdata[cpu])
return 0;
spin_lock(&etmdrvdata[cpu]->spinlock);
if (!etmdrvdata[cpu]->os_unlock) {
etm_os_unlock(etmdrvdata[cpu]);
etmdrvdata[cpu]->os_unlock = true;
}
if (coresight_get_mode(etmdrvdata[cpu]->csdev))
etm_enable_hw(etmdrvdata[cpu]);
spin_unlock(&etmdrvdata[cpu]->spinlock);
return 0;
}
static int etm_dying_cpu(unsigned int cpu)
{
if (!etmdrvdata[cpu])
return 0;
spin_lock(&etmdrvdata[cpu]->spinlock);
if (coresight_get_mode(etmdrvdata[cpu]->csdev))
etm_disable_hw(etmdrvdata[cpu]);
spin_unlock(&etmdrvdata[cpu]->spinlock);
return 0;
}
static bool etm_arch_supported(u8 arch)
{
switch (arch) {
case ETM_ARCH_V3_3:
break;
case ETM_ARCH_V3_5:
break;
case PFT_ARCH_V1_0:
break;
case PFT_ARCH_V1_1:
break;
default:
return false;
}
return true;
}
static void etm_init_arch_data(void *info)
{
u32 etmidr;
u32 etmccr;
struct etm_drvdata *drvdata = info;
/* Make sure all registers are accessible */
etm_os_unlock(drvdata);
CS_UNLOCK(drvdata->base);
/* First dummy read */
(void)etm_readl(drvdata, ETMPDSR);
/* Provide power to ETM: ETMPDCR[3] == 1 */
etm_set_pwrup(drvdata);
/*
* Clear power down bit since when this bit is set writes to
* certain registers might be ignored.
*/
etm_clr_pwrdwn(drvdata);
/*
* Set prog bit. It will be set from reset but this is included to
* ensure it is set
*/
etm_set_prog(drvdata);
/* Find all capabilities */
etmidr = etm_readl(drvdata, ETMIDR);
drvdata->arch = BMVAL(etmidr, 4, 11);
drvdata->port_size = etm_readl(drvdata, ETMCR) & PORT_SIZE_MASK;
drvdata->etmccer = etm_readl(drvdata, ETMCCER);
etmccr = etm_readl(drvdata, ETMCCR);
drvdata->etmccr = etmccr;
drvdata->nr_addr_cmp = BMVAL(etmccr, 0, 3) * 2;
drvdata->nr_cntr = BMVAL(etmccr, 13, 15);
drvdata->nr_ext_inp = BMVAL(etmccr, 17, 19);
drvdata->nr_ext_out = BMVAL(etmccr, 20, 22);
drvdata->nr_ctxid_cmp = BMVAL(etmccr, 24, 25);
etm_set_pwrdwn(drvdata);
etm_clr_pwrup(drvdata);
CS_LOCK(drvdata->base);
}
static int __init etm_hp_setup(void)
{
int ret;
ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ARM_CORESIGHT_STARTING,
"arm/coresight:starting",
etm_starting_cpu, etm_dying_cpu);
if (ret)
return ret;
ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN,
"arm/coresight:online",
etm_online_cpu, NULL);
/* HP dyn state ID returned in ret on success */
if (ret > 0) {
hp_online = ret;
return 0;
}
/* failed dyn state - remove others */
cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING);
return ret;
}
static void etm_hp_clear(void)
{
cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING);
if (hp_online) {
cpuhp_remove_state_nocalls(hp_online);
hp_online = 0;
}
}
static int etm_probe(struct amba_device *adev, const struct amba_id *id)
{
int ret;
void __iomem *base;
struct device *dev = &adev->dev;
struct coresight_platform_data *pdata = NULL;
struct etm_drvdata *drvdata;
struct resource *res = &adev->res;
struct coresight_desc desc = { 0 };
drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
if (!drvdata)
return -ENOMEM;
drvdata->use_cp14 = fwnode_property_read_bool(dev->fwnode, "arm,cp14");
dev_set_drvdata(dev, drvdata);
/* Validity for the resource is already checked by the AMBA core */
base = devm_ioremap_resource(dev, res);
if (IS_ERR(base))
return PTR_ERR(base);
drvdata->base = base;
desc.access = CSDEV_ACCESS_IOMEM(base);
spin_lock_init(&drvdata->spinlock);
drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */
if (!IS_ERR(drvdata->atclk)) {
ret = clk_prepare_enable(drvdata->atclk);
if (ret)
return ret;
}
drvdata->cpu = coresight_get_cpu(dev);
if (drvdata->cpu < 0)
return drvdata->cpu;
desc.name = devm_kasprintf(dev, GFP_KERNEL, "etm%d", drvdata->cpu);
if (!desc.name)
return -ENOMEM;
if (smp_call_function_single(drvdata->cpu,
etm_init_arch_data, drvdata, 1))
dev_err(dev, "ETM arch init failed\n");
if (etm_arch_supported(drvdata->arch) == false)
return -EINVAL;
etm_set_default(&drvdata->config);
pdata = coresight_get_platform_data(dev);
if (IS_ERR(pdata))
return PTR_ERR(pdata);
adev->dev.platform_data = pdata;
desc.type = CORESIGHT_DEV_TYPE_SOURCE;
desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_PROC;
desc.ops = &etm_cs_ops;
desc.pdata = pdata;
desc.dev = dev;
desc.groups = coresight_etm_groups;
drvdata->csdev = coresight_register(&desc);
if (IS_ERR(drvdata->csdev))
return PTR_ERR(drvdata->csdev);
ret = etm_perf_symlink(drvdata->csdev, true);
if (ret) {
coresight_unregister(drvdata->csdev);
return ret;
}
etmdrvdata[drvdata->cpu] = drvdata;
pm_runtime_put(&adev->dev);
dev_info(&drvdata->csdev->dev,
"%s initialized\n", (char *)coresight_get_uci_data(id));
if (boot_enable) {
coresight_enable_sysfs(drvdata->csdev);
drvdata->boot_enable = true;
}
return 0;
}
static void clear_etmdrvdata(void *info)
{
int cpu = *(int *)info;
etmdrvdata[cpu] = NULL;
}
static void etm_remove(struct amba_device *adev)
{
struct etm_drvdata *drvdata = dev_get_drvdata(&adev->dev);
etm_perf_symlink(drvdata->csdev, false);
/*
* Taking hotplug lock here to avoid racing between etm_remove and
* CPU hotplug call backs.
*/
cpus_read_lock();
/*
* The readers for etmdrvdata[] are CPU hotplug call backs
* and PM notification call backs. Change etmdrvdata[i] on
* CPU i ensures these call backs has consistent view
* inside one call back function.
*/
if (smp_call_function_single(drvdata->cpu, clear_etmdrvdata, &drvdata->cpu, 1))
etmdrvdata[drvdata->cpu] = NULL;
cpus_read_unlock();
coresight_unregister(drvdata->csdev);
}
#ifdef CONFIG_PM
static int etm_runtime_suspend(struct device *dev)
{
struct etm_drvdata *drvdata = dev_get_drvdata(dev);
if (drvdata && !IS_ERR(drvdata->atclk))
clk_disable_unprepare(drvdata->atclk);
return 0;
}
static int etm_runtime_resume(struct device *dev)
{
struct etm_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 etm_dev_pm_ops = {
SET_RUNTIME_PM_OPS(etm_runtime_suspend, etm_runtime_resume, NULL)
};
static const struct amba_id etm_ids[] = {
/* ETM 3.3 */
CS_AMBA_ID_DATA(0x000bb921, "ETM 3.3"),
/* ETM 3.5 - Cortex-A5 */
CS_AMBA_ID_DATA(0x000bb955, "ETM 3.5"),
/* ETM 3.5 */
CS_AMBA_ID_DATA(0x000bb956, "ETM 3.5"),
/* PTM 1.0 */
CS_AMBA_ID_DATA(0x000bb950, "PTM 1.0"),
/* PTM 1.1 */
CS_AMBA_ID_DATA(0x000bb95f, "PTM 1.1"),
/* PTM 1.1 Qualcomm */
CS_AMBA_ID_DATA(0x000b006f, "PTM 1.1"),
{ 0, 0, NULL},
};
MODULE_DEVICE_TABLE(amba, etm_ids);
static struct amba_driver etm_driver = {
.drv = {
.name = "coresight-etm3x",
.pm = &etm_dev_pm_ops,
.suppress_bind_attrs = true,
},
.probe = etm_probe,
.remove = etm_remove,
.id_table = etm_ids,
};
static int __init etm_init(void)
{
int ret;
ret = etm_hp_setup();
/* etm_hp_setup() does its own cleanup - exit on error */
if (ret)
return ret;
ret = amba_driver_register(&etm_driver);
if (ret) {
pr_err("Error registering etm3x driver\n");
etm_hp_clear();
}
return ret;
}
static void __exit etm_exit(void)
{
amba_driver_unregister(&etm_driver);
etm_hp_clear();
}
module_init(etm_init);
module_exit(etm_exit);
MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>");
MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>");
MODULE_DESCRIPTION("Arm CoreSight Program Flow Trace driver");
MODULE_LICENSE("GPL v2");