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![Mathieu Poirier](/assets/img/avatar_default.png)
This patch uses the information conveyed by perf_event::attr::config2 to select a sink to use for the session. That way a sink can easily be selected to be used by more than one source, something that isn't currently possible with the sysfs implementation. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-s390@vger.kernel.org Link: http://lkml.kernel.org/r/20190131184714.20388-4-mathieu.poirier@linaro.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
1252 lines
29 KiB
C
1252 lines
29 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (c) 2012, The Linux Foundation. All rights reserved.
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*/
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/types.h>
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#include <linux/device.h>
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#include <linux/io.h>
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#include <linux/err.h>
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#include <linux/export.h>
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#include <linux/slab.h>
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#include <linux/stringhash.h>
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#include <linux/mutex.h>
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#include <linux/clk.h>
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#include <linux/coresight.h>
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#include <linux/of_platform.h>
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#include <linux/delay.h>
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#include <linux/pm_runtime.h>
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#include "coresight-etm-perf.h"
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#include "coresight-priv.h"
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static DEFINE_MUTEX(coresight_mutex);
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/**
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* struct coresight_node - elements of a path, from source to sink
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* @csdev: Address of an element.
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* @link: hook to the list.
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*/
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struct coresight_node {
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struct coresight_device *csdev;
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struct list_head link;
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};
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/*
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* When operating Coresight drivers from the sysFS interface, only a single
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* path can exist from a tracer (associated to a CPU) to a sink.
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*/
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static DEFINE_PER_CPU(struct list_head *, tracer_path);
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/*
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* As of this writing only a single STM can be found in CS topologies. Since
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* there is no way to know if we'll ever see more and what kind of
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* configuration they will enact, for the time being only define a single path
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* for STM.
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*/
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static struct list_head *stm_path;
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/*
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* When losing synchronisation a new barrier packet needs to be inserted at the
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* beginning of the data collected in a buffer. That way the decoder knows that
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* it needs to look for another sync sequence.
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*/
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const u32 barrier_pkt[4] = {0x7fffffff, 0x7fffffff, 0x7fffffff, 0x7fffffff};
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static int coresight_id_match(struct device *dev, void *data)
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{
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int trace_id, i_trace_id;
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struct coresight_device *csdev, *i_csdev;
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csdev = data;
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i_csdev = to_coresight_device(dev);
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/*
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* No need to care about oneself and components that are not
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* sources or not enabled
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*/
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if (i_csdev == csdev || !i_csdev->enable ||
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i_csdev->type != CORESIGHT_DEV_TYPE_SOURCE)
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return 0;
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/* Get the source ID for both compoment */
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trace_id = source_ops(csdev)->trace_id(csdev);
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i_trace_id = source_ops(i_csdev)->trace_id(i_csdev);
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/* All you need is one */
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if (trace_id == i_trace_id)
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return 1;
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return 0;
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}
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static int coresight_source_is_unique(struct coresight_device *csdev)
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{
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int trace_id = source_ops(csdev)->trace_id(csdev);
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/* this shouldn't happen */
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if (trace_id < 0)
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return 0;
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return !bus_for_each_dev(&coresight_bustype, NULL,
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csdev, coresight_id_match);
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}
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static int coresight_find_link_inport(struct coresight_device *csdev,
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struct coresight_device *parent)
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{
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int i;
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struct coresight_connection *conn;
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for (i = 0; i < parent->nr_outport; i++) {
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conn = &parent->conns[i];
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if (conn->child_dev == csdev)
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return conn->child_port;
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}
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dev_err(&csdev->dev, "couldn't find inport, parent: %s, child: %s\n",
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dev_name(&parent->dev), dev_name(&csdev->dev));
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return -ENODEV;
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}
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static int coresight_find_link_outport(struct coresight_device *csdev,
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struct coresight_device *child)
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{
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int i;
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struct coresight_connection *conn;
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for (i = 0; i < csdev->nr_outport; i++) {
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conn = &csdev->conns[i];
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if (conn->child_dev == child)
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return conn->outport;
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}
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dev_err(&csdev->dev, "couldn't find outport, parent: %s, child: %s\n",
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dev_name(&csdev->dev), dev_name(&child->dev));
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return -ENODEV;
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}
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static inline u32 coresight_read_claim_tags(void __iomem *base)
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{
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return readl_relaxed(base + CORESIGHT_CLAIMCLR);
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}
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static inline bool coresight_is_claimed_self_hosted(void __iomem *base)
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{
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return coresight_read_claim_tags(base) == CORESIGHT_CLAIM_SELF_HOSTED;
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}
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static inline bool coresight_is_claimed_any(void __iomem *base)
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{
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return coresight_read_claim_tags(base) != 0;
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}
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static inline void coresight_set_claim_tags(void __iomem *base)
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{
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writel_relaxed(CORESIGHT_CLAIM_SELF_HOSTED, base + CORESIGHT_CLAIMSET);
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isb();
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}
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static inline void coresight_clear_claim_tags(void __iomem *base)
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{
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writel_relaxed(CORESIGHT_CLAIM_SELF_HOSTED, base + CORESIGHT_CLAIMCLR);
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isb();
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}
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/*
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* coresight_claim_device_unlocked : Claim the device for self-hosted usage
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* to prevent an external tool from touching this device. As per PSCI
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* standards, section "Preserving the execution context" => "Debug and Trace
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* save and Restore", DBGCLAIM[1] is reserved for Self-hosted debug/trace and
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* DBGCLAIM[0] is reserved for external tools.
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*
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* Called with CS_UNLOCKed for the component.
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* Returns : 0 on success
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*/
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int coresight_claim_device_unlocked(void __iomem *base)
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{
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if (coresight_is_claimed_any(base))
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return -EBUSY;
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coresight_set_claim_tags(base);
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if (coresight_is_claimed_self_hosted(base))
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return 0;
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/* There was a race setting the tags, clean up and fail */
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coresight_clear_claim_tags(base);
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return -EBUSY;
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}
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int coresight_claim_device(void __iomem *base)
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{
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int rc;
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CS_UNLOCK(base);
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rc = coresight_claim_device_unlocked(base);
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CS_LOCK(base);
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return rc;
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}
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/*
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* coresight_disclaim_device_unlocked : Clear the claim tags for the device.
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* Called with CS_UNLOCKed for the component.
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*/
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void coresight_disclaim_device_unlocked(void __iomem *base)
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{
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if (coresight_is_claimed_self_hosted(base))
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coresight_clear_claim_tags(base);
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else
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/*
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* The external agent may have not honoured our claim
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* and has manipulated it. Or something else has seriously
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* gone wrong in our driver.
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*/
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WARN_ON_ONCE(1);
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}
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void coresight_disclaim_device(void __iomem *base)
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{
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CS_UNLOCK(base);
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coresight_disclaim_device_unlocked(base);
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CS_LOCK(base);
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}
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static int coresight_enable_sink(struct coresight_device *csdev,
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u32 mode, void *data)
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{
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int ret;
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/*
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* We need to make sure the "new" session is compatible with the
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* existing "mode" of operation.
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*/
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if (sink_ops(csdev)->enable) {
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ret = sink_ops(csdev)->enable(csdev, mode, data);
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if (ret)
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return ret;
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csdev->enable = true;
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}
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atomic_inc(csdev->refcnt);
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return 0;
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}
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static void coresight_disable_sink(struct coresight_device *csdev)
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{
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if (atomic_dec_return(csdev->refcnt) == 0) {
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if (sink_ops(csdev)->disable) {
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sink_ops(csdev)->disable(csdev);
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csdev->enable = false;
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}
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}
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}
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static int coresight_enable_link(struct coresight_device *csdev,
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struct coresight_device *parent,
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struct coresight_device *child)
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{
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int ret;
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int link_subtype;
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int refport, inport, outport;
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if (!parent || !child)
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return -EINVAL;
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inport = coresight_find_link_inport(csdev, parent);
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outport = coresight_find_link_outport(csdev, child);
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link_subtype = csdev->subtype.link_subtype;
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if (link_subtype == CORESIGHT_DEV_SUBTYPE_LINK_MERG)
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refport = inport;
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else if (link_subtype == CORESIGHT_DEV_SUBTYPE_LINK_SPLIT)
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refport = outport;
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else
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refport = 0;
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if (refport < 0)
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return refport;
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if (atomic_inc_return(&csdev->refcnt[refport]) == 1) {
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if (link_ops(csdev)->enable) {
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ret = link_ops(csdev)->enable(csdev, inport, outport);
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if (ret) {
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atomic_dec(&csdev->refcnt[refport]);
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return ret;
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}
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}
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}
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csdev->enable = true;
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return 0;
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}
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static void coresight_disable_link(struct coresight_device *csdev,
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struct coresight_device *parent,
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struct coresight_device *child)
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{
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int i, nr_conns;
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int link_subtype;
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int refport, inport, outport;
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if (!parent || !child)
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return;
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inport = coresight_find_link_inport(csdev, parent);
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outport = coresight_find_link_outport(csdev, child);
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link_subtype = csdev->subtype.link_subtype;
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if (link_subtype == CORESIGHT_DEV_SUBTYPE_LINK_MERG) {
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refport = inport;
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nr_conns = csdev->nr_inport;
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} else if (link_subtype == CORESIGHT_DEV_SUBTYPE_LINK_SPLIT) {
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refport = outport;
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nr_conns = csdev->nr_outport;
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} else {
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refport = 0;
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nr_conns = 1;
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}
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if (atomic_dec_return(&csdev->refcnt[refport]) == 0) {
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if (link_ops(csdev)->disable)
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link_ops(csdev)->disable(csdev, inport, outport);
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}
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for (i = 0; i < nr_conns; i++)
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if (atomic_read(&csdev->refcnt[i]) != 0)
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return;
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csdev->enable = false;
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}
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static int coresight_enable_source(struct coresight_device *csdev, u32 mode)
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{
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int ret;
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if (!coresight_source_is_unique(csdev)) {
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dev_warn(&csdev->dev, "traceID %d not unique\n",
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source_ops(csdev)->trace_id(csdev));
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return -EINVAL;
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}
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if (!csdev->enable) {
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if (source_ops(csdev)->enable) {
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ret = source_ops(csdev)->enable(csdev, NULL, mode);
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if (ret)
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return ret;
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}
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csdev->enable = true;
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}
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atomic_inc(csdev->refcnt);
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return 0;
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}
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/**
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* coresight_disable_source - Drop the reference count by 1 and disable
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* the device if there are no users left.
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*
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* @csdev - The coresight device to disable
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*
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* Returns true if the device has been disabled.
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*/
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static bool coresight_disable_source(struct coresight_device *csdev)
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{
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if (atomic_dec_return(csdev->refcnt) == 0) {
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if (source_ops(csdev)->disable)
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source_ops(csdev)->disable(csdev, NULL);
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csdev->enable = false;
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}
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return !csdev->enable;
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}
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/*
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* coresight_disable_path_from : Disable components in the given path beyond
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* @nd in the list. If @nd is NULL, all the components, except the SOURCE are
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* disabled.
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*/
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static void coresight_disable_path_from(struct list_head *path,
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struct coresight_node *nd)
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{
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u32 type;
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struct coresight_device *csdev, *parent, *child;
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if (!nd)
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nd = list_first_entry(path, struct coresight_node, link);
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list_for_each_entry_continue(nd, path, link) {
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csdev = nd->csdev;
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type = csdev->type;
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/*
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* ETF devices are tricky... They can be a link or a sink,
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* depending on how they are configured. If an ETF has been
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* "activated" it will be configured as a sink, otherwise
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* go ahead with the link configuration.
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*/
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if (type == CORESIGHT_DEV_TYPE_LINKSINK)
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type = (csdev == coresight_get_sink(path)) ?
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CORESIGHT_DEV_TYPE_SINK :
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CORESIGHT_DEV_TYPE_LINK;
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switch (type) {
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case CORESIGHT_DEV_TYPE_SINK:
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coresight_disable_sink(csdev);
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break;
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case CORESIGHT_DEV_TYPE_SOURCE:
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/*
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* We skip the first node in the path assuming that it
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* is the source. So we don't expect a source device in
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* the middle of a path.
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*/
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WARN_ON(1);
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break;
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case CORESIGHT_DEV_TYPE_LINK:
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parent = list_prev_entry(nd, link)->csdev;
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child = list_next_entry(nd, link)->csdev;
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coresight_disable_link(csdev, parent, child);
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break;
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default:
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break;
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}
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}
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}
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void coresight_disable_path(struct list_head *path)
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{
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coresight_disable_path_from(path, NULL);
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}
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int coresight_enable_path(struct list_head *path, u32 mode, void *sink_data)
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{
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int ret = 0;
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u32 type;
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struct coresight_node *nd;
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struct coresight_device *csdev, *parent, *child;
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list_for_each_entry_reverse(nd, path, link) {
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csdev = nd->csdev;
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type = csdev->type;
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/*
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* ETF devices are tricky... They can be a link or a sink,
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* depending on how they are configured. If an ETF has been
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* "activated" it will be configured as a sink, otherwise
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* go ahead with the link configuration.
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*/
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if (type == CORESIGHT_DEV_TYPE_LINKSINK)
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type = (csdev == coresight_get_sink(path)) ?
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CORESIGHT_DEV_TYPE_SINK :
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CORESIGHT_DEV_TYPE_LINK;
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switch (type) {
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case CORESIGHT_DEV_TYPE_SINK:
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ret = coresight_enable_sink(csdev, mode, sink_data);
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/*
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* Sink is the first component turned on. If we
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* failed to enable the sink, there are no components
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* that need disabling. Disabling the path here
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* would mean we could disrupt an existing session.
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*/
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if (ret)
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goto out;
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break;
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case CORESIGHT_DEV_TYPE_SOURCE:
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/* sources are enabled from either sysFS or Perf */
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break;
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case CORESIGHT_DEV_TYPE_LINK:
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parent = list_prev_entry(nd, link)->csdev;
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child = list_next_entry(nd, link)->csdev;
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ret = coresight_enable_link(csdev, parent, child);
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if (ret)
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goto err;
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break;
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default:
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goto err;
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}
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}
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out:
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return ret;
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err:
|
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coresight_disable_path_from(path, nd);
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goto out;
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}
|
|
|
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struct coresight_device *coresight_get_sink(struct list_head *path)
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{
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struct coresight_device *csdev;
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|
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if (!path)
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return NULL;
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|
|
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csdev = list_last_entry(path, struct coresight_node, link)->csdev;
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if (csdev->type != CORESIGHT_DEV_TYPE_SINK &&
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csdev->type != CORESIGHT_DEV_TYPE_LINKSINK)
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return NULL;
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|
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return csdev;
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}
|
|
|
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static int coresight_enabled_sink(struct device *dev, void *data)
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{
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bool *reset = data;
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struct coresight_device *csdev = to_coresight_device(dev);
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|
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if ((csdev->type == CORESIGHT_DEV_TYPE_SINK ||
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|
csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) &&
|
|
csdev->activated) {
|
|
/*
|
|
* Now that we have a handle on the sink for this session,
|
|
* disable the sysFS "enable_sink" flag so that possible
|
|
* concurrent perf session that wish to use another sink don't
|
|
* trip on it. Doing so has no ramification for the current
|
|
* session.
|
|
*/
|
|
if (*reset)
|
|
csdev->activated = false;
|
|
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* coresight_get_enabled_sink - returns the first enabled sink found on the bus
|
|
* @deactivate: Whether the 'enable_sink' flag should be reset
|
|
*
|
|
* When operated from perf the deactivate parameter should be set to 'true'.
|
|
* That way the "enabled_sink" flag of the sink that was selected can be reset,
|
|
* allowing for other concurrent perf sessions to choose a different sink.
|
|
*
|
|
* When operated from sysFS users have full control and as such the deactivate
|
|
* parameter should be set to 'false', hence mandating users to explicitly
|
|
* clear the flag.
|
|
*/
|
|
struct coresight_device *coresight_get_enabled_sink(bool deactivate)
|
|
{
|
|
struct device *dev = NULL;
|
|
|
|
dev = bus_find_device(&coresight_bustype, NULL, &deactivate,
|
|
coresight_enabled_sink);
|
|
|
|
return dev ? to_coresight_device(dev) : NULL;
|
|
}
|
|
|
|
static int coresight_sink_by_id(struct device *dev, void *data)
|
|
{
|
|
struct coresight_device *csdev = to_coresight_device(dev);
|
|
unsigned long hash;
|
|
|
|
if (csdev->type == CORESIGHT_DEV_TYPE_SINK ||
|
|
csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) {
|
|
|
|
if (!csdev->ea)
|
|
return 0;
|
|
/*
|
|
* See function etm_perf_add_symlink_sink() to know where
|
|
* this comes from.
|
|
*/
|
|
hash = (unsigned long)csdev->ea->var;
|
|
|
|
if ((u32)hash == *(u32 *)data)
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* coresight_get_sink_by_id - returns the sink that matches the id
|
|
* @id: Id of the sink to match
|
|
*
|
|
* The name of a sink is unique, whether it is found on the AMBA bus or
|
|
* otherwise. As such the hash of that name can easily be used to identify
|
|
* a sink.
|
|
*/
|
|
struct coresight_device *coresight_get_sink_by_id(u32 id)
|
|
{
|
|
struct device *dev = NULL;
|
|
|
|
dev = bus_find_device(&coresight_bustype, NULL, &id,
|
|
coresight_sink_by_id);
|
|
|
|
return dev ? to_coresight_device(dev) : NULL;
|
|
}
|
|
|
|
/*
|
|
* coresight_grab_device - Power up this device and any of the helper
|
|
* devices connected to it for trace operation. Since the helper devices
|
|
* don't appear on the trace path, they should be handled along with the
|
|
* the master device.
|
|
*/
|
|
static void coresight_grab_device(struct coresight_device *csdev)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < csdev->nr_outport; i++) {
|
|
struct coresight_device *child = csdev->conns[i].child_dev;
|
|
|
|
if (child && child->type == CORESIGHT_DEV_TYPE_HELPER)
|
|
pm_runtime_get_sync(child->dev.parent);
|
|
}
|
|
pm_runtime_get_sync(csdev->dev.parent);
|
|
}
|
|
|
|
/*
|
|
* coresight_drop_device - Release this device and any of the helper
|
|
* devices connected to it.
|
|
*/
|
|
static void coresight_drop_device(struct coresight_device *csdev)
|
|
{
|
|
int i;
|
|
|
|
pm_runtime_put(csdev->dev.parent);
|
|
for (i = 0; i < csdev->nr_outport; i++) {
|
|
struct coresight_device *child = csdev->conns[i].child_dev;
|
|
|
|
if (child && child->type == CORESIGHT_DEV_TYPE_HELPER)
|
|
pm_runtime_put(child->dev.parent);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* _coresight_build_path - recursively build a path from a @csdev to a sink.
|
|
* @csdev: The device to start from.
|
|
* @path: The list to add devices to.
|
|
*
|
|
* The tree of Coresight device is traversed until an activated sink is
|
|
* found. From there the sink is added to the list along with all the
|
|
* devices that led to that point - the end result is a list from source
|
|
* to sink. In that list the source is the first device and the sink the
|
|
* last one.
|
|
*/
|
|
static int _coresight_build_path(struct coresight_device *csdev,
|
|
struct coresight_device *sink,
|
|
struct list_head *path)
|
|
{
|
|
int i;
|
|
bool found = false;
|
|
struct coresight_node *node;
|
|
|
|
/* An activated sink has been found. Enqueue the element */
|
|
if (csdev == sink)
|
|
goto out;
|
|
|
|
/* Not a sink - recursively explore each port found on this element */
|
|
for (i = 0; i < csdev->nr_outport; i++) {
|
|
struct coresight_device *child_dev = csdev->conns[i].child_dev;
|
|
|
|
if (child_dev &&
|
|
_coresight_build_path(child_dev, sink, path) == 0) {
|
|
found = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (!found)
|
|
return -ENODEV;
|
|
|
|
out:
|
|
/*
|
|
* A path from this element to a sink has been found. The elements
|
|
* leading to the sink are already enqueued, all that is left to do
|
|
* is tell the PM runtime core we need this element and add a node
|
|
* for it.
|
|
*/
|
|
node = kzalloc(sizeof(struct coresight_node), GFP_KERNEL);
|
|
if (!node)
|
|
return -ENOMEM;
|
|
|
|
coresight_grab_device(csdev);
|
|
node->csdev = csdev;
|
|
list_add(&node->link, path);
|
|
|
|
return 0;
|
|
}
|
|
|
|
struct list_head *coresight_build_path(struct coresight_device *source,
|
|
struct coresight_device *sink)
|
|
{
|
|
struct list_head *path;
|
|
int rc;
|
|
|
|
if (!sink)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
path = kzalloc(sizeof(struct list_head), GFP_KERNEL);
|
|
if (!path)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
INIT_LIST_HEAD(path);
|
|
|
|
rc = _coresight_build_path(source, sink, path);
|
|
if (rc) {
|
|
kfree(path);
|
|
return ERR_PTR(rc);
|
|
}
|
|
|
|
return path;
|
|
}
|
|
|
|
/**
|
|
* coresight_release_path - release a previously built path.
|
|
* @path: the path to release.
|
|
*
|
|
* Go through all the elements of a path and 1) removed it from the list and
|
|
* 2) free the memory allocated for each node.
|
|
*/
|
|
void coresight_release_path(struct list_head *path)
|
|
{
|
|
struct coresight_device *csdev;
|
|
struct coresight_node *nd, *next;
|
|
|
|
list_for_each_entry_safe(nd, next, path, link) {
|
|
csdev = nd->csdev;
|
|
|
|
coresight_drop_device(csdev);
|
|
list_del(&nd->link);
|
|
kfree(nd);
|
|
}
|
|
|
|
kfree(path);
|
|
path = NULL;
|
|
}
|
|
|
|
/** coresight_validate_source - make sure a source has the right credentials
|
|
* @csdev: the device structure for a source.
|
|
* @function: the function this was called from.
|
|
*
|
|
* Assumes the coresight_mutex is held.
|
|
*/
|
|
static int coresight_validate_source(struct coresight_device *csdev,
|
|
const char *function)
|
|
{
|
|
u32 type, subtype;
|
|
|
|
type = csdev->type;
|
|
subtype = csdev->subtype.source_subtype;
|
|
|
|
if (type != CORESIGHT_DEV_TYPE_SOURCE) {
|
|
dev_err(&csdev->dev, "wrong device type in %s\n", function);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_PROC &&
|
|
subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE) {
|
|
dev_err(&csdev->dev, "wrong device subtype in %s\n", function);
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int coresight_enable(struct coresight_device *csdev)
|
|
{
|
|
int cpu, ret = 0;
|
|
struct coresight_device *sink;
|
|
struct list_head *path;
|
|
enum coresight_dev_subtype_source subtype;
|
|
|
|
subtype = csdev->subtype.source_subtype;
|
|
|
|
mutex_lock(&coresight_mutex);
|
|
|
|
ret = coresight_validate_source(csdev, __func__);
|
|
if (ret)
|
|
goto out;
|
|
|
|
if (csdev->enable) {
|
|
/*
|
|
* There could be multiple applications driving the software
|
|
* source. So keep the refcount for each such user when the
|
|
* source is already enabled.
|
|
*/
|
|
if (subtype == CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE)
|
|
atomic_inc(csdev->refcnt);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Search for a valid sink for this session but don't reset the
|
|
* "enable_sink" flag in sysFS. Users get to do that explicitly.
|
|
*/
|
|
sink = coresight_get_enabled_sink(false);
|
|
if (!sink) {
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
path = coresight_build_path(csdev, sink);
|
|
if (IS_ERR(path)) {
|
|
pr_err("building path(s) failed\n");
|
|
ret = PTR_ERR(path);
|
|
goto out;
|
|
}
|
|
|
|
ret = coresight_enable_path(path, CS_MODE_SYSFS, NULL);
|
|
if (ret)
|
|
goto err_path;
|
|
|
|
ret = coresight_enable_source(csdev, CS_MODE_SYSFS);
|
|
if (ret)
|
|
goto err_source;
|
|
|
|
switch (subtype) {
|
|
case CORESIGHT_DEV_SUBTYPE_SOURCE_PROC:
|
|
/*
|
|
* When working from sysFS it is important to keep track
|
|
* of the paths that were created so that they can be
|
|
* undone in 'coresight_disable()'. Since there can only
|
|
* be a single session per tracer (when working from sysFS)
|
|
* a per-cpu variable will do just fine.
|
|
*/
|
|
cpu = source_ops(csdev)->cpu_id(csdev);
|
|
per_cpu(tracer_path, cpu) = path;
|
|
break;
|
|
case CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE:
|
|
stm_path = path;
|
|
break;
|
|
default:
|
|
/* We can't be here */
|
|
break;
|
|
}
|
|
|
|
out:
|
|
mutex_unlock(&coresight_mutex);
|
|
return ret;
|
|
|
|
err_source:
|
|
coresight_disable_path(path);
|
|
|
|
err_path:
|
|
coresight_release_path(path);
|
|
goto out;
|
|
}
|
|
EXPORT_SYMBOL_GPL(coresight_enable);
|
|
|
|
void coresight_disable(struct coresight_device *csdev)
|
|
{
|
|
int cpu, ret;
|
|
struct list_head *path = NULL;
|
|
|
|
mutex_lock(&coresight_mutex);
|
|
|
|
ret = coresight_validate_source(csdev, __func__);
|
|
if (ret)
|
|
goto out;
|
|
|
|
if (!csdev->enable || !coresight_disable_source(csdev))
|
|
goto out;
|
|
|
|
switch (csdev->subtype.source_subtype) {
|
|
case CORESIGHT_DEV_SUBTYPE_SOURCE_PROC:
|
|
cpu = source_ops(csdev)->cpu_id(csdev);
|
|
path = per_cpu(tracer_path, cpu);
|
|
per_cpu(tracer_path, cpu) = NULL;
|
|
break;
|
|
case CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE:
|
|
path = stm_path;
|
|
stm_path = NULL;
|
|
break;
|
|
default:
|
|
/* We can't be here */
|
|
break;
|
|
}
|
|
|
|
coresight_disable_path(path);
|
|
coresight_release_path(path);
|
|
|
|
out:
|
|
mutex_unlock(&coresight_mutex);
|
|
}
|
|
EXPORT_SYMBOL_GPL(coresight_disable);
|
|
|
|
static ssize_t enable_sink_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct coresight_device *csdev = to_coresight_device(dev);
|
|
|
|
return scnprintf(buf, PAGE_SIZE, "%u\n", csdev->activated);
|
|
}
|
|
|
|
static ssize_t enable_sink_store(struct device *dev,
|
|
struct device_attribute *attr,
|
|
const char *buf, size_t size)
|
|
{
|
|
int ret;
|
|
unsigned long val;
|
|
struct coresight_device *csdev = to_coresight_device(dev);
|
|
|
|
ret = kstrtoul(buf, 10, &val);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (val)
|
|
csdev->activated = true;
|
|
else
|
|
csdev->activated = false;
|
|
|
|
return size;
|
|
|
|
}
|
|
static DEVICE_ATTR_RW(enable_sink);
|
|
|
|
static ssize_t enable_source_show(struct device *dev,
|
|
struct device_attribute *attr, char *buf)
|
|
{
|
|
struct coresight_device *csdev = to_coresight_device(dev);
|
|
|
|
return scnprintf(buf, PAGE_SIZE, "%u\n", csdev->enable);
|
|
}
|
|
|
|
static ssize_t enable_source_store(struct device *dev,
|
|
struct device_attribute *attr,
|
|
const char *buf, size_t size)
|
|
{
|
|
int ret = 0;
|
|
unsigned long val;
|
|
struct coresight_device *csdev = to_coresight_device(dev);
|
|
|
|
ret = kstrtoul(buf, 10, &val);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (val) {
|
|
ret = coresight_enable(csdev);
|
|
if (ret)
|
|
return ret;
|
|
} else {
|
|
coresight_disable(csdev);
|
|
}
|
|
|
|
return size;
|
|
}
|
|
static DEVICE_ATTR_RW(enable_source);
|
|
|
|
static struct attribute *coresight_sink_attrs[] = {
|
|
&dev_attr_enable_sink.attr,
|
|
NULL,
|
|
};
|
|
ATTRIBUTE_GROUPS(coresight_sink);
|
|
|
|
static struct attribute *coresight_source_attrs[] = {
|
|
&dev_attr_enable_source.attr,
|
|
NULL,
|
|
};
|
|
ATTRIBUTE_GROUPS(coresight_source);
|
|
|
|
static struct device_type coresight_dev_type[] = {
|
|
{
|
|
.name = "none",
|
|
},
|
|
{
|
|
.name = "sink",
|
|
.groups = coresight_sink_groups,
|
|
},
|
|
{
|
|
.name = "link",
|
|
},
|
|
{
|
|
.name = "linksink",
|
|
.groups = coresight_sink_groups,
|
|
},
|
|
{
|
|
.name = "source",
|
|
.groups = coresight_source_groups,
|
|
},
|
|
{
|
|
.name = "helper",
|
|
},
|
|
};
|
|
|
|
static void coresight_device_release(struct device *dev)
|
|
{
|
|
struct coresight_device *csdev = to_coresight_device(dev);
|
|
|
|
kfree(csdev->conns);
|
|
kfree(csdev->refcnt);
|
|
kfree(csdev);
|
|
}
|
|
|
|
static int coresight_orphan_match(struct device *dev, void *data)
|
|
{
|
|
int i;
|
|
bool still_orphan = false;
|
|
struct coresight_device *csdev, *i_csdev;
|
|
struct coresight_connection *conn;
|
|
|
|
csdev = data;
|
|
i_csdev = to_coresight_device(dev);
|
|
|
|
/* No need to check oneself */
|
|
if (csdev == i_csdev)
|
|
return 0;
|
|
|
|
/* Move on to another component if no connection is orphan */
|
|
if (!i_csdev->orphan)
|
|
return 0;
|
|
/*
|
|
* Circle throuch all the connection of that component. If we find
|
|
* an orphan connection whose name matches @csdev, link it.
|
|
*/
|
|
for (i = 0; i < i_csdev->nr_outport; i++) {
|
|
conn = &i_csdev->conns[i];
|
|
|
|
/* We have found at least one orphan connection */
|
|
if (conn->child_dev == NULL) {
|
|
/* Does it match this newly added device? */
|
|
if (conn->child_name &&
|
|
!strcmp(dev_name(&csdev->dev), conn->child_name)) {
|
|
conn->child_dev = csdev;
|
|
} else {
|
|
/* This component still has an orphan */
|
|
still_orphan = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
i_csdev->orphan = still_orphan;
|
|
|
|
/*
|
|
* Returning '0' ensures that all known component on the
|
|
* bus will be checked.
|
|
*/
|
|
return 0;
|
|
}
|
|
|
|
static void coresight_fixup_orphan_conns(struct coresight_device *csdev)
|
|
{
|
|
/*
|
|
* No need to check for a return value as orphan connection(s)
|
|
* are hooked-up with each newly added component.
|
|
*/
|
|
bus_for_each_dev(&coresight_bustype, NULL,
|
|
csdev, coresight_orphan_match);
|
|
}
|
|
|
|
|
|
static void coresight_fixup_device_conns(struct coresight_device *csdev)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < csdev->nr_outport; i++) {
|
|
struct coresight_connection *conn = &csdev->conns[i];
|
|
struct device *dev = NULL;
|
|
|
|
if (conn->child_name)
|
|
dev = bus_find_device_by_name(&coresight_bustype, NULL,
|
|
conn->child_name);
|
|
if (dev) {
|
|
conn->child_dev = to_coresight_device(dev);
|
|
/* and put reference from 'bus_find_device()' */
|
|
put_device(dev);
|
|
} else {
|
|
csdev->orphan = true;
|
|
conn->child_dev = NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
static int coresight_remove_match(struct device *dev, void *data)
|
|
{
|
|
int i;
|
|
struct coresight_device *csdev, *iterator;
|
|
struct coresight_connection *conn;
|
|
|
|
csdev = data;
|
|
iterator = to_coresight_device(dev);
|
|
|
|
/* No need to check oneself */
|
|
if (csdev == iterator)
|
|
return 0;
|
|
|
|
/*
|
|
* Circle throuch all the connection of that component. If we find
|
|
* a connection whose name matches @csdev, remove it.
|
|
*/
|
|
for (i = 0; i < iterator->nr_outport; i++) {
|
|
conn = &iterator->conns[i];
|
|
|
|
if (conn->child_dev == NULL)
|
|
continue;
|
|
|
|
if (!strcmp(dev_name(&csdev->dev), conn->child_name)) {
|
|
iterator->orphan = true;
|
|
conn->child_dev = NULL;
|
|
/* No need to continue */
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Returning '0' ensures that all known component on the
|
|
* bus will be checked.
|
|
*/
|
|
return 0;
|
|
}
|
|
|
|
static void coresight_remove_conns(struct coresight_device *csdev)
|
|
{
|
|
bus_for_each_dev(&coresight_bustype, NULL,
|
|
csdev, coresight_remove_match);
|
|
}
|
|
|
|
/**
|
|
* coresight_timeout - loop until a bit has changed to a specific state.
|
|
* @addr: base address of the area of interest.
|
|
* @offset: address of a register, starting from @addr.
|
|
* @position: the position of the bit of interest.
|
|
* @value: the value the bit should have.
|
|
*
|
|
* Return: 0 as soon as the bit has taken the desired state or -EAGAIN if
|
|
* TIMEOUT_US has elapsed, which ever happens first.
|
|
*/
|
|
|
|
int coresight_timeout(void __iomem *addr, u32 offset, int position, int value)
|
|
{
|
|
int i;
|
|
u32 val;
|
|
|
|
for (i = TIMEOUT_US; i > 0; i--) {
|
|
val = __raw_readl(addr + 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;
|
|
}
|
|
|
|
struct bus_type coresight_bustype = {
|
|
.name = "coresight",
|
|
};
|
|
|
|
static int __init coresight_init(void)
|
|
{
|
|
return bus_register(&coresight_bustype);
|
|
}
|
|
postcore_initcall(coresight_init);
|
|
|
|
struct coresight_device *coresight_register(struct coresight_desc *desc)
|
|
{
|
|
int ret;
|
|
int link_subtype;
|
|
int nr_refcnts = 1;
|
|
atomic_t *refcnts = NULL;
|
|
struct coresight_device *csdev;
|
|
|
|
csdev = kzalloc(sizeof(*csdev), GFP_KERNEL);
|
|
if (!csdev) {
|
|
ret = -ENOMEM;
|
|
goto err_out;
|
|
}
|
|
|
|
if (desc->type == CORESIGHT_DEV_TYPE_LINK ||
|
|
desc->type == CORESIGHT_DEV_TYPE_LINKSINK) {
|
|
link_subtype = desc->subtype.link_subtype;
|
|
|
|
if (link_subtype == CORESIGHT_DEV_SUBTYPE_LINK_MERG)
|
|
nr_refcnts = desc->pdata->nr_inport;
|
|
else if (link_subtype == CORESIGHT_DEV_SUBTYPE_LINK_SPLIT)
|
|
nr_refcnts = desc->pdata->nr_outport;
|
|
}
|
|
|
|
refcnts = kcalloc(nr_refcnts, sizeof(*refcnts), GFP_KERNEL);
|
|
if (!refcnts) {
|
|
ret = -ENOMEM;
|
|
goto err_free_csdev;
|
|
}
|
|
|
|
csdev->refcnt = refcnts;
|
|
|
|
csdev->nr_inport = desc->pdata->nr_inport;
|
|
csdev->nr_outport = desc->pdata->nr_outport;
|
|
|
|
csdev->conns = desc->pdata->conns;
|
|
|
|
csdev->type = desc->type;
|
|
csdev->subtype = desc->subtype;
|
|
csdev->ops = desc->ops;
|
|
csdev->orphan = false;
|
|
|
|
csdev->dev.type = &coresight_dev_type[desc->type];
|
|
csdev->dev.groups = desc->groups;
|
|
csdev->dev.parent = desc->dev;
|
|
csdev->dev.release = coresight_device_release;
|
|
csdev->dev.bus = &coresight_bustype;
|
|
dev_set_name(&csdev->dev, "%s", desc->pdata->name);
|
|
|
|
ret = device_register(&csdev->dev);
|
|
if (ret) {
|
|
put_device(&csdev->dev);
|
|
/*
|
|
* All resources are free'd explicitly via
|
|
* coresight_device_release(), triggered from put_device().
|
|
*/
|
|
goto err_out;
|
|
}
|
|
|
|
if (csdev->type == CORESIGHT_DEV_TYPE_SINK ||
|
|
csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) {
|
|
ret = etm_perf_add_symlink_sink(csdev);
|
|
|
|
if (ret) {
|
|
device_unregister(&csdev->dev);
|
|
/*
|
|
* As with the above, all resources are free'd
|
|
* explicitly via coresight_device_release() triggered
|
|
* from put_device(), which is in turn called from
|
|
* function device_unregister().
|
|
*/
|
|
goto err_out;
|
|
}
|
|
}
|
|
|
|
mutex_lock(&coresight_mutex);
|
|
|
|
coresight_fixup_device_conns(csdev);
|
|
coresight_fixup_orphan_conns(csdev);
|
|
|
|
mutex_unlock(&coresight_mutex);
|
|
|
|
return csdev;
|
|
|
|
err_free_csdev:
|
|
kfree(csdev);
|
|
err_out:
|
|
return ERR_PTR(ret);
|
|
}
|
|
EXPORT_SYMBOL_GPL(coresight_register);
|
|
|
|
void coresight_unregister(struct coresight_device *csdev)
|
|
{
|
|
etm_perf_del_symlink_sink(csdev);
|
|
/* Remove references of that device in the topology */
|
|
coresight_remove_conns(csdev);
|
|
device_unregister(&csdev->dev);
|
|
}
|
|
EXPORT_SYMBOL_GPL(coresight_unregister);
|