| Message ID | 20200113213149.25599-9-mike.leach@linaro.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | CoreSight CTI Driver | expand |
On 13/01/2020 21:31, Mike Leach wrote: > The CoreSight subsystem enables a path of devices from source to sink. > Any CTI devices associated with the path devices must be enabled at the > same time. > > This patch adds an associated coresight_device element to the main > coresight device structure, and uses this to create associations between > the CTI and other devices based on the device tree data. The associated > device element is used to enable CTI in conjunction with the path elements. > > CTI devices are reference counted so where a single CTI is associated with > multiple elements on the path, it will be enabled on the first associated > device enable, and disabled with the last associated device disable. > > Signed-off-by: Mike Leach <mike.leach@linaro.org> > Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> > --- > drivers/hwtracing/coresight/coresight-cti.c | 129 ++++++++++++++++++ > drivers/hwtracing/coresight/coresight-cti.h | 1 + > .../hwtracing/coresight/coresight-platform.c | 1 + > drivers/hwtracing/coresight/coresight-priv.h | 12 ++ > drivers/hwtracing/coresight/coresight.c | 71 +++++++++- > include/linux/coresight.h | 4 + > 6 files changed, 213 insertions(+), 5 deletions(-) > > diff --git a/drivers/hwtracing/coresight/coresight-cti.c b/drivers/hwtracing/coresight/coresight-cti.c > index 77c2af247917..2be1b310e854 100644 > --- a/drivers/hwtracing/coresight/coresight-cti.c > +++ b/drivers/hwtracing/coresight/coresight-cti.c > @@ -4,6 +4,7 @@ > * Author: Mike Leach <mike.leach@linaro.org> > */ > > +#include <linux/property.h> > #include "coresight-cti.h" > > /** > @@ -440,6 +441,131 @@ int cti_channel_setop(struct device *dev, enum cti_chan_set_op op, > return err; > } > > +/* > + * Look for a matching connection device name in the list of connections. > + * If found then swap in the csdev name, set trig con association pointer > + * and return found. > + */ > +static bool > +cti_match_fixup_csdev(struct cti_device *ctidev, const char *node_name, > + struct coresight_device *csdev) > +{ > + struct cti_trig_con *trig_con; super minor nit: Please use "struct cti_trig_con *tc;" consistent with the naming everywhere else. Helps a lot in reading the code, especially which has a lot of different structures. > + const char *csdev_name; > + > + list_for_each_entry(trig_con, &ctidev->trig_cons, node) { > + if (trig_con->con_dev_name) { This was allocated via devm_* and ... > + if (!strcmp(node_name, trig_con->con_dev_name)) { > + /* match: so swap in csdev name & dev */ > + kfree(trig_con->con_dev_name); ... we free it here using kfree() without devm_ being aware. This could cause double-free when the device is removed. This should either be devm_kfree() or simply overwritten with the new string and leave the device cleanup to free it. > + csdev_name = dev_name(&csdev->dev); > + trig_con->con_dev_name = > + kstrdup(csdev_name, GFP_KERNEL); Please use devm_kstrdup() here on the CTI device to have a consistent allocation. > + trig_con->con_dev = csdev; > + return true; > + } > + } > + } > + return false; > +} > > +/* > + * Removing the associated devices is easier. > + * A CTI will not have a value for csdev->ect_dev. > + */ > +void cti_remove_assoc_from_csdev(struct coresight_device *csdev) > +{ > + struct cti_drvdata *ctidrv; > + struct cti_trig_con *tc; > + struct cti_device *ctidev; > + > + mutex_lock(&ect_mutex); > + if (csdev->ect_dev) { > + ctidrv = csdev_to_cti_drvdata(csdev->ect_dev); > + ctidev = &ctidrv->ctidev; > + list_for_each_entry(tc, &ctidev->trig_cons, node) { > + if (tc->con_dev == csdev->ect_dev) { > + tc->con_dev = NULL; Should we clear/free the name too ? > + break; > + } > + } > + csdev->ect_dev = NULL; > + } > + mutex_unlock(&ect_mutex); > +} > +EXPORT_SYMBOL_GPL(cti_remove_assoc_from_csdev); > + ... > diff --git a/drivers/hwtracing/coresight/coresight-cti.h b/drivers/hwtracing/coresight/coresight-cti.h > index 469a06a1bb78..578d7e9ac67e 100644 > --- a/drivers/hwtracing/coresight/coresight-cti.h > +++ b/drivers/hwtracing/coresight/coresight-cti.h > @@ -216,6 +216,7 @@ int cti_channel_setop(struct device *dev, enum cti_chan_set_op op, > u32 channel_idx); > struct coresight_platform_data * > coresight_cti_get_platform_data(struct device *dev); > +const char *cti_plat_get_node_name(struct fwnode_handle *fwnode); > > /* cti powered and enabled */ > static inline bool cti_active(struct cti_config *cfg) > diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c > index 43418a2126ff..421d4fc95f41 100644 > --- a/drivers/hwtracing/coresight/coresight-platform.c > +++ b/drivers/hwtracing/coresight/coresight-platform.c > @@ -313,6 +313,7 @@ static int of_get_coresight_platform_data(struct device *dev, > > return 0; > } > + nit : spurious hunk ? > #else > static inline int > of_get_coresight_platform_data(struct device *dev, Otherwise looks good to me Suzuki
Hi Suzuki, On Wed, 15 Jan 2020 at 11:14, Suzuki Kuruppassery Poulose <suzuki.poulose@arm.com> wrote: > > On 13/01/2020 21:31, Mike Leach wrote: > > The CoreSight subsystem enables a path of devices from source to sink. > > Any CTI devices associated with the path devices must be enabled at the > > same time. > > > > This patch adds an associated coresight_device element to the main > > coresight device structure, and uses this to create associations between > > the CTI and other devices based on the device tree data. The associated > > device element is used to enable CTI in conjunction with the path elements. > > > > CTI devices are reference counted so where a single CTI is associated with > > multiple elements on the path, it will be enabled on the first associated > > device enable, and disabled with the last associated device disable. > > > > Signed-off-by: Mike Leach <mike.leach@linaro.org> > > Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> > > --- > > drivers/hwtracing/coresight/coresight-cti.c | 129 ++++++++++++++++++ > > drivers/hwtracing/coresight/coresight-cti.h | 1 + > > .../hwtracing/coresight/coresight-platform.c | 1 + > > drivers/hwtracing/coresight/coresight-priv.h | 12 ++ > > drivers/hwtracing/coresight/coresight.c | 71 +++++++++- > > include/linux/coresight.h | 4 + > > 6 files changed, 213 insertions(+), 5 deletions(-) > > > > diff --git a/drivers/hwtracing/coresight/coresight-cti.c b/drivers/hwtracing/coresight/coresight-cti.c > > index 77c2af247917..2be1b310e854 100644 > > --- a/drivers/hwtracing/coresight/coresight-cti.c > > +++ b/drivers/hwtracing/coresight/coresight-cti.c > > @@ -4,6 +4,7 @@ > > * Author: Mike Leach <mike.leach@linaro.org> > > */ > > > > +#include <linux/property.h> > > #include "coresight-cti.h" > > > > /** > > @@ -440,6 +441,131 @@ int cti_channel_setop(struct device *dev, enum cti_chan_set_op op, > > return err; > > } > > > > +/* > > + * Look for a matching connection device name in the list of connections. > > + * If found then swap in the csdev name, set trig con association pointer > > + * and return found. > > + */ > > +static bool > > +cti_match_fixup_csdev(struct cti_device *ctidev, const char *node_name, > > + struct coresight_device *csdev) > > +{ > > + struct cti_trig_con *trig_con; > > super minor nit: Please use "struct cti_trig_con *tc;" consistent with > the naming everywhere else. Helps a lot in reading the code, especially > which has a lot of different structures. > > > + const char *csdev_name; > > + > > + list_for_each_entry(trig_con, &ctidev->trig_cons, node) { > > + if (trig_con->con_dev_name) { > > This was allocated via devm_* and ... > > > + if (!strcmp(node_name, trig_con->con_dev_name)) { > > + /* match: so swap in csdev name & dev */ > > + kfree(trig_con->con_dev_name); > > ... we free it here using kfree() without devm_ being aware. This could > cause double-free when the device is removed. This should either be > devm_kfree() or simply overwritten with the new string and leave > the device cleanup to free it. > Agreed - fixed up in v9. > > + csdev_name = dev_name(&csdev->dev); > > + trig_con->con_dev_name = > > + kstrdup(csdev_name, GFP_KERNEL); > > Please use devm_kstrdup() here on the CTI device to have a consistent > allocation. > > > > + trig_con->con_dev = csdev; > > + return true; > > + } > > + } > > + } > > + return false; > > +} > > > > > > +/* > > + * Removing the associated devices is easier. > > + * A CTI will not have a value for csdev->ect_dev. > > + */ > > +void cti_remove_assoc_from_csdev(struct coresight_device *csdev) > > +{ > > + struct cti_drvdata *ctidrv; > > + struct cti_trig_con *tc; > > + struct cti_device *ctidev; > > + > > + mutex_lock(&ect_mutex); > > + if (csdev->ect_dev) { > > + ctidrv = csdev_to_cti_drvdata(csdev->ect_dev); > > + ctidev = &ctidrv->ctidev; > > + list_for_each_entry(tc, &ctidev->trig_cons, node) { > > + if (tc->con_dev == csdev->ect_dev) { > > + tc->con_dev = NULL; > > Should we clear/free the name too ? > Not now devm_ allocation is being used. > > + break; > > + } > > + } > > + csdev->ect_dev = NULL; > > + } > > + mutex_unlock(&ect_mutex); > > +} > > +EXPORT_SYMBOL_GPL(cti_remove_assoc_from_csdev); > > + > > ... > > > diff --git a/drivers/hwtracing/coresight/coresight-cti.h b/drivers/hwtracing/coresight/coresight-cti.h > > index 469a06a1bb78..578d7e9ac67e 100644 > > --- a/drivers/hwtracing/coresight/coresight-cti.h > > +++ b/drivers/hwtracing/coresight/coresight-cti.h > > @@ -216,6 +216,7 @@ int cti_channel_setop(struct device *dev, enum cti_chan_set_op op, > > u32 channel_idx); > > struct coresight_platform_data * > > coresight_cti_get_platform_data(struct device *dev); > > +const char *cti_plat_get_node_name(struct fwnode_handle *fwnode); > > > > /* cti powered and enabled */ > > static inline bool cti_active(struct cti_config *cfg) > > diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c > > index 43418a2126ff..421d4fc95f41 100644 > > --- a/drivers/hwtracing/coresight/coresight-platform.c > > +++ b/drivers/hwtracing/coresight/coresight-platform.c > > @@ -313,6 +313,7 @@ static int of_get_coresight_platform_data(struct device *dev, > > > > return 0; > > } > > + > > nit : spurious hunk ? > > > #else > > static inline int > > of_get_coresight_platform_data(struct device *dev, > > Otherwise looks good to me > > Suzuki Thanks. Mike
diff --git a/drivers/hwtracing/coresight/coresight-cti.c b/drivers/hwtracing/coresight/coresight-cti.c index 77c2af247917..2be1b310e854 100644 --- a/drivers/hwtracing/coresight/coresight-cti.c +++ b/drivers/hwtracing/coresight/coresight-cti.c @@ -4,6 +4,7 @@ * Author: Mike Leach <mike.leach@linaro.org> */ +#include <linux/property.h> #include "coresight-cti.h" /** @@ -440,6 +441,131 @@ int cti_channel_setop(struct device *dev, enum cti_chan_set_op op, return err; } +/* + * Look for a matching connection device name in the list of connections. + * If found then swap in the csdev name, set trig con association pointer + * and return found. + */ +static bool +cti_match_fixup_csdev(struct cti_device *ctidev, const char *node_name, + struct coresight_device *csdev) +{ + struct cti_trig_con *trig_con; + const char *csdev_name; + + list_for_each_entry(trig_con, &ctidev->trig_cons, node) { + if (trig_con->con_dev_name) { + if (!strcmp(node_name, trig_con->con_dev_name)) { + /* match: so swap in csdev name & dev */ + kfree(trig_con->con_dev_name); + csdev_name = dev_name(&csdev->dev); + trig_con->con_dev_name = + kstrdup(csdev_name, GFP_KERNEL); + trig_con->con_dev = csdev; + return true; + } + } + } + return false; +} + +/* + * Search the cti list to add an associated CTI into the supplied CS device + * This will set the association if CTI declared before the CS device. + * (called from coresight_register() with coresight_mutex locked). + */ +void cti_add_assoc_to_csdev(struct coresight_device *csdev) +{ + struct cti_drvdata *ect_item; + struct cti_device *ctidev; + const char *node_name = NULL; + + /* protect the list */ + mutex_lock(&ect_mutex); + + /* exit if current is an ECT device.*/ + if ((csdev->type == CORESIGHT_DEV_TYPE_ECT) || list_empty(&ect_net)) + goto cti_add_done; + + /* if we didn't find the csdev previously we used the fwnode name */ + node_name = cti_plat_get_node_name(dev_fwnode(csdev->dev.parent)); + if (!node_name) + goto cti_add_done; + + /* for each CTI in list... */ + list_for_each_entry(ect_item, &ect_net, node) { + ctidev = &ect_item->ctidev; + if (cti_match_fixup_csdev(ctidev, node_name, csdev)) { + /* + * if we found a matching csdev then update the ECT + * association pointer for the device with this CTI. + */ + csdev->ect_dev = ect_item->csdev; + break; + } + } +cti_add_done: + mutex_unlock(&ect_mutex); +} +EXPORT_SYMBOL_GPL(cti_add_assoc_to_csdev); + +/* + * Removing the associated devices is easier. + * A CTI will not have a value for csdev->ect_dev. + */ +void cti_remove_assoc_from_csdev(struct coresight_device *csdev) +{ + struct cti_drvdata *ctidrv; + struct cti_trig_con *tc; + struct cti_device *ctidev; + + mutex_lock(&ect_mutex); + if (csdev->ect_dev) { + ctidrv = csdev_to_cti_drvdata(csdev->ect_dev); + ctidev = &ctidrv->ctidev; + list_for_each_entry(tc, &ctidev->trig_cons, node) { + if (tc->con_dev == csdev->ect_dev) { + tc->con_dev = NULL; + break; + } + } + csdev->ect_dev = NULL; + } + mutex_unlock(&ect_mutex); +} +EXPORT_SYMBOL_GPL(cti_remove_assoc_from_csdev); + +/* + * Update the cross references where the associated device was found + * while we were building the connection info. This will occur if the + * assoc device was registered before the CTI. + */ +static void cti_update_conn_xrefs(struct cti_drvdata *drvdata) +{ + struct cti_trig_con *tc; + struct cti_device *ctidev = &drvdata->ctidev; + + list_for_each_entry(tc, &ctidev->trig_cons, node) { + if (tc->con_dev) + /* set tc->con_dev->ect_dev */ + coresight_set_assoc_ectdev_mutex(tc->con_dev, + drvdata->csdev); + } +} + +static void cti_remove_conn_xrefs(struct cti_drvdata *drvdata) +{ + struct cti_trig_con *tc; + struct cti_device *ctidev = &drvdata->ctidev; + + list_for_each_entry(tc, &ctidev->trig_cons, node) { + if (tc->con_dev) { + coresight_set_assoc_ectdev_mutex(tc->con_dev, + NULL); + } + } +} + /** cti ect operations **/ int cti_enable(struct coresight_device *csdev) { @@ -474,6 +600,7 @@ static void cti_device_release(struct device *dev) struct cti_drvdata *ect_item, *ect_tmp; mutex_lock(&ect_mutex); + cti_remove_conn_xrefs(drvdata); /* remove from the list */ list_for_each_entry_safe(ect_item, ect_tmp, &ect_net, node) { @@ -565,6 +692,8 @@ static int cti_probe(struct amba_device *adev, const struct amba_id *id) /* add to list of CTI devices */ mutex_lock(&ect_mutex); list_add(&drvdata->node, &ect_net); + /* set any cross references */ + cti_update_conn_xrefs(drvdata); mutex_unlock(&ect_mutex); /* set up release chain */ diff --git a/drivers/hwtracing/coresight/coresight-cti.h b/drivers/hwtracing/coresight/coresight-cti.h index 469a06a1bb78..578d7e9ac67e 100644 --- a/drivers/hwtracing/coresight/coresight-cti.h +++ b/drivers/hwtracing/coresight/coresight-cti.h @@ -216,6 +216,7 @@ int cti_channel_setop(struct device *dev, enum cti_chan_set_op op, u32 channel_idx); struct coresight_platform_data * coresight_cti_get_platform_data(struct device *dev); +const char *cti_plat_get_node_name(struct fwnode_handle *fwnode); /* cti powered and enabled */ static inline bool cti_active(struct cti_config *cfg) diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c index 43418a2126ff..421d4fc95f41 100644 --- a/drivers/hwtracing/coresight/coresight-platform.c +++ b/drivers/hwtracing/coresight/coresight-platform.c @@ -313,6 +313,7 @@ static int of_get_coresight_platform_data(struct device *dev, return 0; } + #else static inline int of_get_coresight_platform_data(struct device *dev, diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h index 357ffef7b825..890f9a5c97c6 100644 --- a/drivers/hwtracing/coresight/coresight-priv.h +++ b/drivers/hwtracing/coresight/coresight-priv.h @@ -162,6 +162,16 @@ static inline int etm_readl_cp14(u32 off, unsigned int *val) { return 0; } static inline int etm_writel_cp14(u32 off, u32 val) { return 0; } #endif +#ifdef CONFIG_CORESIGHT_CTI +extern void cti_add_assoc_to_csdev(struct coresight_device *csdev); +extern void cti_remove_assoc_from_csdev(struct coresight_device *csdev); + +#else +static inline void cti_add_assoc_to_csdev(struct coresight_device *csdev) {} +static inline void +cti_remove_assoc_from_csdev(struct coresight_device *csdev) {} +#endif + /* * Macros and inline functions to handle CoreSight UCI data and driver * private data in AMBA ID table entries, and extract data values. @@ -204,5 +214,7 @@ static inline void *coresight_get_uci_data(const struct amba_id *id) void coresight_release_platform_data(struct coresight_platform_data *pdata); struct coresight_device * coresight_find_csdev_by_fwnode(struct fwnode_handle *r_fwnode); +void coresight_set_assoc_ectdev_mutex(struct coresight_device *csdev, + struct coresight_device *ect_csdev); #endif diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c index 39a5d9f7a395..c71553c09f8e 100644 --- a/drivers/hwtracing/coresight/coresight.c +++ b/drivers/hwtracing/coresight/coresight.c @@ -216,6 +216,44 @@ void coresight_disclaim_device(void __iomem *base) CS_LOCK(base); } +/* enable or disable an associated CTI device of the supplied CS device */ +static int +coresight_control_assoc_ectdev(struct coresight_device *csdev, bool enable) +{ + int ect_ret = 0; + struct coresight_device *ect_csdev = csdev->ect_dev; + + if (!ect_csdev) + return 0; + + if (enable) { + if (ect_ops(ect_csdev)->enable) + ect_ret = ect_ops(ect_csdev)->enable(ect_csdev); + } else { + if (ect_ops(ect_csdev)->disable) + ect_ret = ect_ops(ect_csdev)->disable(ect_csdev); + } + + /* output warning if ECT enable is preventing trace operation */ + if (ect_ret) + dev_info(&csdev->dev, "Associated ECT device (%s) %s failed\n", + dev_name(&ect_csdev->dev), + enable ? "enable" : "disable"); + return ect_ret; +} + +/* + * Set the associated ect / cti device while holding the coresight_mutex + * to avoid a race with coresight_enable that may try to use this value. + */ +void coresight_set_assoc_ectdev_mutex(struct coresight_device *csdev, + struct coresight_device *ect_csdev) +{ + mutex_lock(&coresight_mutex); + csdev->ect_dev = ect_csdev; + mutex_unlock(&coresight_mutex); +} + static int coresight_enable_sink(struct coresight_device *csdev, u32 mode, void *data) { @@ -228,9 +266,14 @@ static int coresight_enable_sink(struct coresight_device *csdev, if (!sink_ops(csdev)->enable) return -EINVAL; - ret = sink_ops(csdev)->enable(csdev, mode, data); + ret = coresight_control_assoc_ectdev(csdev, true); if (ret) return ret; + ret = sink_ops(csdev)->enable(csdev, mode, data); + if (ret) { + coresight_control_assoc_ectdev(csdev, false); + return ret; + } csdev->enable = true; return 0; @@ -246,6 +289,7 @@ static void coresight_disable_sink(struct coresight_device *csdev) ret = sink_ops(csdev)->disable(csdev); if (ret) return; + coresight_control_assoc_ectdev(csdev, false); csdev->enable = false; } @@ -269,8 +313,15 @@ static int coresight_enable_link(struct coresight_device *csdev, if (link_subtype == CORESIGHT_DEV_SUBTYPE_LINK_SPLIT && outport < 0) return outport; - if (link_ops(csdev)->enable) - ret = link_ops(csdev)->enable(csdev, inport, outport); + if (link_ops(csdev)->enable) { + ret = coresight_control_assoc_ectdev(csdev, true); + if (!ret) { + ret = link_ops(csdev)->enable(csdev, inport, outport); + if (ret) + coresight_control_assoc_ectdev(csdev, false); + } + } + if (!ret) csdev->enable = true; @@ -300,8 +351,10 @@ static void coresight_disable_link(struct coresight_device *csdev, nr_conns = 1; } - if (link_ops(csdev)->disable) + if (link_ops(csdev)->disable) { link_ops(csdev)->disable(csdev, inport, outport); + coresight_control_assoc_ectdev(csdev, false); + } for (i = 0; i < nr_conns; i++) if (atomic_read(&csdev->refcnt[i]) != 0) @@ -322,9 +375,14 @@ static int coresight_enable_source(struct coresight_device *csdev, u32 mode) if (!csdev->enable) { if (source_ops(csdev)->enable) { - ret = source_ops(csdev)->enable(csdev, NULL, mode); + ret = coresight_control_assoc_ectdev(csdev, true); if (ret) return ret; + ret = source_ops(csdev)->enable(csdev, NULL, mode); + if (ret) { + coresight_control_assoc_ectdev(csdev, false); + return ret; + }; } csdev->enable = true; } @@ -347,6 +405,7 @@ static bool coresight_disable_source(struct coresight_device *csdev) if (atomic_dec_return(csdev->refcnt) == 0) { if (source_ops(csdev)->disable) source_ops(csdev)->disable(csdev, NULL); + coresight_control_assoc_ectdev(csdev, false); csdev->enable = false; } return !csdev->enable; @@ -964,6 +1023,7 @@ static void coresight_device_release(struct device *dev) { struct coresight_device *csdev = to_coresight_device(dev); + cti_remove_assoc_from_csdev(csdev); fwnode_handle_put(csdev->dev.fwnode); kfree(csdev->refcnt); kfree(csdev); @@ -1246,6 +1306,7 @@ struct coresight_device *coresight_register(struct coresight_desc *desc) coresight_fixup_device_conns(csdev); coresight_fixup_orphan_conns(csdev); + cti_add_assoc_to_csdev(csdev); mutex_unlock(&coresight_mutex); diff --git a/include/linux/coresight.h b/include/linux/coresight.h index b3e582d96a34..193cc9dbf448 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -163,6 +163,8 @@ struct coresight_connection { * activated but not yet enabled. Enabling for a _sink_ * appens when a source has been selected for that it. * @ea: Device attribute for sink representation under PMU directory. + * @ect_dev: Associated cross trigger device. Not part of the trace data + * path or connections. */ struct coresight_device { struct coresight_platform_data *pdata; @@ -176,6 +178,8 @@ struct coresight_device { /* sink specific fields */ bool activated; /* true only if a sink is part of a path */ struct dev_ext_attribute *ea; + /* cross trigger handling */ + struct coresight_device *ect_dev; }; /*