coresight: etm4x: Add complex configuration handlers to etmv4

Adds in handlers to allow the ETMv4 to use the complex configuration
support. Features and configurations can be loaded and selected in the
device.

Link: https://lore.kernel.org/r/20210723165444.1048-8-mike.leach@linaro.org
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20210818194022.379573-8-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/hwtracing/coresight/Makefile

@@ -16,7 +16,8 @@ obj-$(CONFIG_CORESIGHT_SOURCE_ETM3X) += coresight-etm3x.o
 coresight-etm3x-y := coresight-etm3x-core.o coresight-etm-cp14.o \
 		     coresight-etm3x-sysfs.o
 obj-$(CONFIG_CORESIGHT_SOURCE_ETM4X) += coresight-etm4x.o
-coresight-etm4x-y := coresight-etm4x-core.o coresight-etm4x-sysfs.o
+coresight-etm4x-y := coresight-etm4x-core.o coresight-etm4x-sysfs.o \
+			coresight-etm4x-cfg.o
 obj-$(CONFIG_CORESIGHT_STM) += coresight-stm.o
 obj-$(CONFIG_CORESIGHT_CPU_DEBUG) += coresight-cpu-debug.o
 obj-$(CONFIG_CORESIGHT_CATU) += coresight-catu.o

drivers/hwtracing/coresight/coresight-etm4x-cfg.c

@@ -0,0 +1,182 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright(C) 2020 Linaro Limited. All rights reserved.
+ * Author: Mike Leach <mike.leach@linaro.org>
+ */
+
+#include "coresight-etm4x.h"
+#include "coresight-etm4x-cfg.h"
+#include "coresight-priv.h"
+#include "coresight-syscfg.h"
+
+/* defines to associate register IDs with driver data locations */
+#define CHECKREG(cval, elem) \
+	{ \
+		if (offset == cval) { \
+			reg_csdev->driver_regval = &drvcfg->elem; \
+			err = 0; \
+			break; \
+		} \
+	}
+
+#define CHECKREGIDX(cval, elem, off_idx, mask)	\
+	{ \
+		if (mask == cval) { \
+			reg_csdev->driver_regval = &drvcfg->elem[off_idx]; \
+			err = 0; \
+			break; \
+		} \
+	}
+
+/**
+ * etm4_cfg_map_reg_offset - validate and map the register offset into a
+ *			     location in the driver config struct.
+ *
+ * Limits the number of registers that can be accessed and programmed in
+ * features, to those which are used to control the trace capture parameters.
+ *
+ * Omits or limits access to those which the driver must use exclusively.
+ *
+ * Invalid offsets will result in fail code return and feature load failure.
+ *
+ * @drvdata:	driver data to map into.
+ * @reg:	register to map.
+ * @offset:	device offset for the register
+ */
+static int etm4_cfg_map_reg_offset(struct etmv4_drvdata *drvdata,
+				   struct cscfg_regval_csdev *reg_csdev, u32 offset)
+{
+	int err = -EINVAL, idx;
+	struct etmv4_config *drvcfg = &drvdata->config;
+	u32 off_mask;
+
+	if (((offset >= TRCEVENTCTL0R) && (offset <= TRCVIPCSSCTLR)) ||
+	    ((offset >= TRCSEQRSTEVR) && (offset <= TRCEXTINSELR)) ||
+	    ((offset >= TRCCIDCCTLR0) && (offset <= TRCVMIDCCTLR1))) {
+		do {
+			CHECKREG(TRCEVENTCTL0R, eventctrl0);
+			CHECKREG(TRCEVENTCTL1R, eventctrl1);
+			CHECKREG(TRCSTALLCTLR, stall_ctrl);
+			CHECKREG(TRCTSCTLR, ts_ctrl);
+			CHECKREG(TRCSYNCPR, syncfreq);
+			CHECKREG(TRCCCCTLR, ccctlr);
+			CHECKREG(TRCBBCTLR, bb_ctrl);
+			CHECKREG(TRCVICTLR, vinst_ctrl);
+			CHECKREG(TRCVIIECTLR, viiectlr);
+			CHECKREG(TRCVISSCTLR, vissctlr);
+			CHECKREG(TRCVIPCSSCTLR, vipcssctlr);
+			CHECKREG(TRCSEQRSTEVR, seq_rst);
+			CHECKREG(TRCSEQSTR, seq_state);
+			CHECKREG(TRCEXTINSELR, ext_inp);
+			CHECKREG(TRCCIDCCTLR0, ctxid_mask0);
+			CHECKREG(TRCCIDCCTLR1, ctxid_mask1);
+			CHECKREG(TRCVMIDCCTLR0, vmid_mask0);
+			CHECKREG(TRCVMIDCCTLR1, vmid_mask1);
+		} while (0);
+	} else if ((offset & GENMASK(11, 4)) == TRCSEQEVRn(0)) {
+		/* sequencer state control registers */
+		idx = (offset & GENMASK(3, 0)) / 4;
+		if (idx < ETM_MAX_SEQ_STATES) {
+			reg_csdev->driver_regval = &drvcfg->seq_ctrl[idx];
+			err = 0;
+		}
+	} else if ((offset >= TRCSSCCRn(0)) && (offset <= TRCSSPCICRn(7))) {
+		/* 32 bit, 8 off indexed register sets */
+		idx = (offset & GENMASK(4, 0)) / 4;
+		off_mask =  (offset & GENMASK(11, 5));
+		do {
+			CHECKREGIDX(TRCSSCCRn(0), ss_ctrl, idx, off_mask);
+			CHECKREGIDX(TRCSSCSRn(0), ss_status, idx, off_mask);
+			CHECKREGIDX(TRCSSPCICRn(0), ss_pe_cmp, idx, off_mask);
+		} while (0);
+	} else if ((offset >= TRCCIDCVRn(0)) && (offset <= TRCVMIDCVRn(7))) {
+		/* 64 bit, 8 off indexed register sets */
+		idx = (offset & GENMASK(5, 0)) / 8;
+		off_mask = (offset & GENMASK(11, 6));
+		do {
+			CHECKREGIDX(TRCCIDCVRn(0), ctxid_pid, idx, off_mask);
+			CHECKREGIDX(TRCVMIDCVRn(0), vmid_val, idx, off_mask);
+		} while (0);
+	} else if ((offset >= TRCRSCTLRn(2)) &&
+		   (offset <= TRCRSCTLRn((ETM_MAX_RES_SEL - 1)))) {
+		/* 32 bit resource selection regs, 32 off, skip fixed 0,1 */
+		idx = (offset & GENMASK(6, 0)) / 4;
+		if (idx < ETM_MAX_RES_SEL) {
+			reg_csdev->driver_regval = &drvcfg->res_ctrl[idx];
+			err = 0;
+		}
+	} else if ((offset >= TRCACVRn(0)) &&
+		   (offset <= TRCACATRn((ETM_MAX_SINGLE_ADDR_CMP - 1)))) {
+		/* 64 bit addr cmp regs, 16 off */
+		idx = (offset & GENMASK(6, 0)) / 8;
+		off_mask = offset & GENMASK(11, 7);
+		do {
+			CHECKREGIDX(TRCACVRn(0), addr_val, idx, off_mask);
+			CHECKREGIDX(TRCACATRn(0), addr_acc, idx, off_mask);
+		} while (0);
+	} else if ((offset >= TRCCNTRLDVRn(0)) &&
+		   (offset <= TRCCNTVRn((ETMv4_MAX_CNTR - 1)))) {
+		/* 32 bit counter regs, 4 off (ETMv4_MAX_CNTR - 1) */
+		idx = (offset &  GENMASK(3, 0)) / 4;
+		off_mask = offset &  GENMASK(11, 4);
+		do {
+			CHECKREGIDX(TRCCNTRLDVRn(0), cntrldvr, idx, off_mask);
+			CHECKREGIDX(TRCCNTCTLRn(0), cntr_ctrl, idx, off_mask);
+			CHECKREGIDX(TRCCNTVRn(0), cntr_val, idx, off_mask);
+		} while (0);
+	}
+	return err;
+}
+
+/**
+ * etm4_cfg_load_feature - load a feature into a device instance.
+ *
+ * @csdev:	An ETMv4 CoreSight device.
+ * @feat:	The feature to be loaded.
+ *
+ * The function will load a feature instance into the device, checking that
+ * the register definitions are valid for the device.
+ *
+ * Parameter and register definitions will be converted into internal
+ * structures that are used to set the values in the driver when the
+ * feature is enabled for the device.
+ *
+ * The feature spinlock pointer is initialised to the same spinlock
+ * that the driver uses to protect the internal register values.
+ */
+static int etm4_cfg_load_feature(struct coresight_device *csdev,
+				 struct cscfg_feature_csdev *feat_csdev)
+{
+	struct device *dev = csdev->dev.parent;
+	struct etmv4_drvdata *drvdata = dev_get_drvdata(dev);
+	const struct cscfg_feature_desc *feat_desc = feat_csdev->feat_desc;
+	u32 offset;
+	int i = 0, err = 0;
+
+	/*
+	 * essential we set the device spinlock - this is used in the generic
+	 * programming routines when copying values into the drvdata structures
+	 * via the pointers setup in etm4_cfg_map_reg_offset().
+	 */
+	feat_csdev->drv_spinlock = &drvdata->spinlock;
+
+	/* process the register descriptions */
+	for (i = 0; i < feat_csdev->nr_regs && !err; i++) {
+		offset = feat_desc->regs_desc[i].offset;
+		err = etm4_cfg_map_reg_offset(drvdata, &feat_csdev->regs_csdev[i], offset);
+	}
+	return err;
+}
+
+/* match information when loading configurations */
+#define CS_CFG_ETM4_MATCH_FLAGS	(CS_CFG_MATCH_CLASS_SRC_ALL | \
+				 CS_CFG_MATCH_CLASS_SRC_ETM4)
+
+int etm4_cscfg_register(struct coresight_device *csdev)
+{
+	struct cscfg_csdev_feat_ops ops;
+
+	ops.load_feat = &etm4_cfg_load_feature;
+
+	return cscfg_register_csdev(csdev, CS_CFG_ETM4_MATCH_FLAGS, &ops);
+}

drivers/hwtracing/coresight/coresight-etm4x-cfg.h

@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2014-2020, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef _CORESIGHT_ETM4X_CFG_H
+#define _CORESIGHT_ETM4X_CFG_H
+
+#include "coresight-config.h"
+#include "coresight-etm4x.h"
+
+/* ETMv4 specific config functions */
+int etm4_cscfg_register(struct coresight_device *csdev);
+
+#endif /* CORESIGHT_ETM4X_CFG_H */

drivers/hwtracing/coresight/coresight-etm4x-core.c

@@ -39,6 +39,8 @@
 
 #include "coresight-etm4x.h"
 #include "coresight-etm-perf.h"
+#include "coresight-etm4x-cfg.h"
+#include "coresight-syscfg.h"
 
 static int boot_enable;
 module_param(boot_enable, int, 0444);
@@ -561,12 +563,15 @@ out:
 	return ret;
 }
 
-static int etm4_parse_event_config(struct etmv4_drvdata *drvdata,
+static int etm4_parse_event_config(struct coresight_device *csdev,
 				   struct perf_event *event)
 {
 	int ret = 0;
+	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 	struct etmv4_config *config = &drvdata->config;
 	struct perf_event_attr *attr = &event->attr;
+	unsigned long cfg_hash;
+	int preset;
 
 	/* Clear configuration from previous run */
 	memset(config, 0, sizeof(struct etmv4_config));
@@ -632,6 +637,20 @@ static int etm4_parse_event_config(struct etmv4_drvdata *drvdata,
 		/* bit[12], Return stack enable bit */
 		config->cfg |= BIT(12);
 
+	/*
+	 * Set any selected configuration and preset.
+	 *
+	 * This extracts the values of PMU_FORMAT_ATTR(configid) and PMU_FORMAT_ATTR(preset)
+	 * in the perf attributes defined in coresight-etm-perf.c.
+	 * configid uses bits 63:32 of attr->config2, preset uses bits 3:0 of attr->config.
+	 * A zero configid means no configuration active, preset = 0 means no preset selected.
+	 */
+	if (attr->config2 & GENMASK_ULL(63, 32)) {
+		cfg_hash = (u32)(attr->config2 >> 32);
+		preset = attr->config & 0xF;
+		ret = cscfg_csdev_enable_active_config(csdev, cfg_hash, preset);
+	}
+
 out:
 	return ret;
 }
@@ -648,7 +667,7 @@ static int etm4_enable_perf(struct coresight_device *csdev,
 	}
 
 	/* Configure the tracer based on the session's specifics */
-	ret = etm4_parse_event_config(drvdata, event);
+	ret = etm4_parse_event_config(csdev, event);
 	if (ret)
 		goto out;
 	/* And enable it */
@@ -794,11 +813,18 @@ static int etm4_disable_perf(struct coresight_device *csdev,
 	u32 control;
 	struct etm_filters *filters = event->hw.addr_filters;
 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+	struct perf_event_attr *attr = &event->attr;
 
 	if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id()))
 		return -EINVAL;
 
 	etm4_disable_hw(drvdata);
+	/*
+	 * The config_id occupies bits 63:32 of the config2 perf event attr
+	 * field. If this is non-zero then we will have enabled a config.
+	 */
+	if (attr->config2 & GENMASK_ULL(63, 32))
+		cscfg_csdev_disable_active_config(csdev);
 
 	/*
 	 * Check if the start/stop logic was active when the unit was stopped.
@@ -1939,6 +1965,13 @@ static int etm4_probe(struct device *dev, void __iomem *base, u32 etm_pid)
 		return ret;
 	}
 
+	/* register with config infrastructure & load any current features */
+	ret = etm4_cscfg_register(drvdata->csdev);
+	if (ret) {
+		coresight_unregister(drvdata->csdev);
+		return ret;
+	}
+
 	etmdrvdata[drvdata->cpu] = drvdata;
 
 	dev_info(&drvdata->csdev->dev, "CPU%d: %s v%d.%d initialized\n",
@@ -2025,6 +2058,7 @@ static int __exit etm4_remove_dev(struct etmv4_drvdata *drvdata)
 
 	cpus_read_unlock();
 
+	cscfg_unregister_csdev(drvdata->csdev);
 	coresight_unregister(drvdata->csdev);
 
 	return 0;

drivers/hwtracing/coresight/coresight-etm4x-sysfs.c

@@ -9,6 +9,7 @@
 #include <linux/sysfs.h>
 #include "coresight-etm4x.h"
 #include "coresight-priv.h"
+#include "coresight-syscfg.h"
 
 static int etm4_set_mode_exclude(struct etmv4_drvdata *drvdata, bool exclude)
 {
@@ -269,6 +270,8 @@ static ssize_t reset_store(struct device *dev,
 
 	spin_unlock(&drvdata->spinlock);
 
+	cscfg_csdev_reset_feats(to_coresight_device(dev));
+
 	return size;
 }
 static DEVICE_ATTR_WO(reset);