Replicators associated with CPU clusters reside in the cluster's power domain. Unlike system-wide replicators, their registers are only accessible when the cluster is powered on. Standard runtime PM may not suffice to wake up a cluster from low-power states, making direct register access unreliable during initialization or operation.
Enhance the replicator driver to support these per-cluster devices:
1. Safe Initialization: - Identify per-cluster replicators via device properties. - Use smp_call_function_single() to perform hardware initialization (reset and claim tag clearing) on a CPU within the cluster. - Refactor the probe flow to encapsulate device registration in replicator_add_coresight_dev().
2. Cross-CPU Enablement: - Update replicator_enable() to use smp_call_function_single() when enabling the hardware on a cluster-bound replicator.
3. Claim/Disclaim Handling: - Introduce replicator_claim/disclaim_device_unlocked() to manage device access safely before full framework registration.
This ensures that replicator operations remain robust even when the associated CPU cluster is in low-power states, while maintaining compatibility with existing system-level replicators.
Signed-off-by: Yuanfang Zhang yuanfang.zhang@oss.qualcomm.com --- drivers/hwtracing/coresight/coresight-replicator.c | 200 +++++++++++++++++---- 1 file changed, 167 insertions(+), 33 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/hwtracing/coresight/coresight-replicator.c index e6472658235dc479cec91ac18f3737f76f8c74f0..c11da452559c73af6709b39d03b646cb4779736f 100644 --- a/drivers/hwtracing/coresight/coresight-replicator.c +++ b/drivers/hwtracing/coresight/coresight-replicator.c @@ -13,6 +13,7 @@ #include <linux/io.h> #include <linux/err.h> #include <linux/slab.h> +#include <linux/pm_domain.h> #include <linux/pm_runtime.h> #include <linux/property.h> #include <linux/clk.h> @@ -35,6 +36,7 @@ DEFINE_CORESIGHT_DEVLIST(replicator_devs, "replicator"); * @csdev: component vitals needed by the framework * @spinlock: serialize enable/disable operations. * @check_idfilter_val: check if the context is lost upon clock removal. + * @supported_cpus: Represent the CPUs related to this funnel. */ struct replicator_drvdata { void __iomem *base; @@ -43,18 +45,61 @@ struct replicator_drvdata { struct coresight_device *csdev; raw_spinlock_t spinlock; bool check_idfilter_val; + struct cpumask *supported_cpus; };
-static void dynamic_replicator_reset(struct replicator_drvdata *drvdata) +struct replicator_smp_arg { + struct replicator_drvdata *drvdata; + int outport; + int rc; +}; + +static void replicator_clear_self_claim_tag(struct replicator_drvdata *drvdata) +{ + struct csdev_access access = CSDEV_ACCESS_IOMEM(drvdata->base); + + coresight_clear_self_claim_tag(&access); +} + +static int replicator_claim_device_unlocked(struct replicator_drvdata *drvdata) +{ + struct coresight_device *csdev = drvdata->csdev; + struct csdev_access access = CSDEV_ACCESS_IOMEM(drvdata->base); + u32 claim_tag; + + if (csdev) + return coresight_claim_device_unlocked(csdev); + + writel_relaxed(CORESIGHT_CLAIM_SELF_HOSTED, drvdata->base + CORESIGHT_CLAIMSET); + + claim_tag = readl_relaxed(drvdata->base + CORESIGHT_CLAIMCLR); + if (claim_tag != CORESIGHT_CLAIM_SELF_HOSTED) { + coresight_clear_self_claim_tag_unlocked(&access); + return -EBUSY; + } + + return 0; +} + +static void replicator_disclaim_device_unlocked(struct replicator_drvdata *drvdata) { struct coresight_device *csdev = drvdata->csdev; + struct csdev_access access = CSDEV_ACCESS_IOMEM(drvdata->base); + + if (csdev) + return coresight_disclaim_device_unlocked(csdev);
+ coresight_clear_self_claim_tag_unlocked(&access); +} + +static void dynamic_replicator_reset(struct replicator_drvdata *drvdata) +{ CS_UNLOCK(drvdata->base);
- if (!coresight_claim_device_unlocked(csdev)) { + if (!replicator_claim_device_unlocked(drvdata)) { writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0); writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1); - coresight_disclaim_device_unlocked(csdev); + replicator_disclaim_device_unlocked(drvdata); }
CS_LOCK(drvdata->base); @@ -116,6 +161,34 @@ static int dynamic_replicator_enable(struct replicator_drvdata *drvdata, return rc; }
+static void replicator_enable_hw_smp_call(void *info) +{ + struct replicator_smp_arg *arg = info; + + arg->rc = dynamic_replicator_enable(arg->drvdata, 0, arg->outport); +} + +static int replicator_enable_hw(struct replicator_drvdata *drvdata, + int inport, int outport) +{ + int cpu, ret; + struct replicator_smp_arg arg = { 0 }; + + if (!drvdata->supported_cpus) + return dynamic_replicator_enable(drvdata, 0, outport); + + arg.drvdata = drvdata; + arg.outport = outport; + + for_each_cpu(cpu, drvdata->supported_cpus) { + ret = smp_call_function_single(cpu, replicator_enable_hw_smp_call, &arg, 1); + if (!ret) + return arg.rc; + } + + return ret; +} + static int replicator_enable(struct coresight_device *csdev, struct coresight_connection *in, struct coresight_connection *out) @@ -126,19 +199,24 @@ static int replicator_enable(struct coresight_device *csdev, bool first_enable = false;
raw_spin_lock_irqsave(&drvdata->spinlock, flags); - if (out->src_refcnt == 0) { - if (drvdata->base) - rc = dynamic_replicator_enable(drvdata, in->dest_port, - out->src_port); - if (!rc) - first_enable = true; - } - if (!rc) + + if (out->src_refcnt == 0) + first_enable = true; + else out->src_refcnt++; raw_spin_unlock_irqrestore(&drvdata->spinlock, flags);
- if (first_enable) - dev_dbg(&csdev->dev, "REPLICATOR enabled\n"); + if (first_enable) { + if (drvdata->base) + rc = replicator_enable_hw(drvdata, in->dest_port, + out->src_port); + if (!rc) { + out->src_refcnt++; + dev_dbg(&csdev->dev, "REPLICATOR enabled\n"); + return rc; + } + } + return rc; }
@@ -217,23 +295,69 @@ static const struct attribute_group *replicator_groups[] = { NULL, };
+static int replicator_add_coresight_dev(struct device *dev) +{ + struct coresight_desc desc = { 0 }; + struct replicator_drvdata *drvdata = dev_get_drvdata(dev); + + if (drvdata->base) { + desc.groups = replicator_groups; + desc.access = CSDEV_ACCESS_IOMEM(drvdata->base); + } + + desc.name = coresight_alloc_device_name(&replicator_devs, dev); + if (!desc.name) + return -ENOMEM; + + desc.type = CORESIGHT_DEV_TYPE_LINK; + desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_SPLIT; + desc.ops = &replicator_cs_ops; + desc.pdata = dev->platform_data; + desc.dev = dev; + + drvdata->csdev = coresight_register(&desc); + if (IS_ERR(drvdata->csdev)) + return PTR_ERR(drvdata->csdev); + + return 0; +} + +static void replicator_init_hw(struct replicator_drvdata *drvdata) +{ + replicator_clear_self_claim_tag(drvdata); + replicator_reset(drvdata); +} + +static void replicator_init_on_cpu(void *info) +{ + struct replicator_drvdata *drvdata = info; + + replicator_init_hw(drvdata); +} + +static struct cpumask *replicator_get_supported_cpus(struct device *dev) +{ + struct generic_pm_domain *pd; + + pd = pd_to_genpd(dev->pm_domain); + if (pd) + return pd->cpus; + + return NULL; +} + static int replicator_probe(struct device *dev, struct resource *res) { struct coresight_platform_data *pdata = NULL; struct replicator_drvdata *drvdata; - struct coresight_desc desc = { 0 }; void __iomem *base; - int ret; + int cpu, ret;
if (is_of_node(dev_fwnode(dev)) && of_device_is_compatible(dev->of_node, "arm,coresight-replicator")) dev_warn_once(dev, "Uses OBSOLETE CoreSight replicator binding\n");
- desc.name = coresight_alloc_device_name(&replicator_devs, dev); - if (!desc.name) - return -ENOMEM; - drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL); if (!drvdata) return -ENOMEM; @@ -251,9 +375,6 @@ static int replicator_probe(struct device *dev, struct resource *res) if (IS_ERR(base)) return PTR_ERR(base); drvdata->base = base; - desc.groups = replicator_groups; - desc.access = CSDEV_ACCESS_IOMEM(base); - coresight_clear_self_claim_tag(&desc.access); }
if (fwnode_property_present(dev_fwnode(dev), @@ -268,25 +389,38 @@ static int replicator_probe(struct device *dev, struct resource *res) dev->platform_data = pdata;
raw_spin_lock_init(&drvdata->spinlock); - desc.type = CORESIGHT_DEV_TYPE_LINK; - desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_SPLIT; - desc.ops = &replicator_cs_ops; - desc.pdata = dev->platform_data; - desc.dev = dev;
- drvdata->csdev = coresight_register(&desc); - if (IS_ERR(drvdata->csdev)) - return PTR_ERR(drvdata->csdev); + if (fwnode_property_present(dev_fwnode(dev), "qcom,cpu-bound-components")) { + drvdata->supported_cpus = replicator_get_supported_cpus(dev); + if (!drvdata->supported_cpus) + return -EINVAL; + + cpus_read_lock(); + for_each_cpu(cpu, drvdata->supported_cpus) { + ret = smp_call_function_single(cpu, + replicator_init_on_cpu, drvdata, 1); + if (!ret) + break; + } + cpus_read_unlock();
- replicator_reset(drvdata); - return 0; + if (ret) + return 0; + } else if (res) { + replicator_init_hw(drvdata); + } + + ret = replicator_add_coresight_dev(dev); + + return ret; }
static int replicator_remove(struct device *dev) { struct replicator_drvdata *drvdata = dev_get_drvdata(dev);
- coresight_unregister(drvdata->csdev); + if (drvdata->csdev) + coresight_unregister(drvdata->csdev); return 0; }