[RFC PATCH v3 6/9] coresight: config: Add preloaded configurations

[Mike Leach <mike.leach@linaro.org>]

Preload set of configurations.

This patch creates a small set of preloaded configurations and features
that are available immediately after coresight has been initialised.

The current set provides a strobing feature for ETMv4, that creates a
periodic sampling of trace by switching trace generation on and off
using counters in the ETM.

A configuration called "autofdo" is also provided that uses the 'strobing'
feature and provides a couple of preset values, selectable on the perf
command line.

Signed-off-by: Mike Leach <mike.leach@linaro.org>
---
 drivers/hwtracing/coresight/Makefile          |   3 +-
 .../coresight/coresight-cfg-preload.c         | 160 ++++++++++++++++++
 drivers/hwtracing/coresight/coresight-core.c  |   6 +
 .../hwtracing/coresight/coresight-syscfg.h    |   1 +
 4 files changed, 169 insertions(+), 1 deletion(-)
 create mode 100644 drivers/hwtracing/coresight/coresight-cfg-preload.c

diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index ea544206204d..9de5586cfd1a 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile
@@ -4,7 +4,8 @@
 #
 obj-$(CONFIG_CORESIGHT) += coresight.o
 coresight-y := coresight-core.o  coresight-etm-perf.o coresight-platform.o \
-		coresight-sysfs.o coresight-syscfg.o coresight-config.o
+		coresight-sysfs.o coresight-syscfg.o coresight-config.o \
+		coresight-cfg-preload.o
 obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o
 coresight-tmc-y := coresight-tmc-core.o coresight-tmc-etf.o \
 		      coresight-tmc-etr.o
diff --git a/drivers/hwtracing/coresight/coresight-cfg-preload.c b/drivers/hwtracing/coresight/coresight-cfg-preload.c
new file mode 100644
index 000000000000..0975d64a1d9e
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-cfg-preload.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright(C) 2020 Linaro Limited. All rights reserved.
+ * Author: Mike Leach <mike.leach@linaro.org>
+ */
+
+#include "coresight-config.h"
+#include "coresight-syscfg.h"
+#include "coresight-etm4x-cfg.h"
+
+/* preload configurations and features */
+
+/* preload in features for ETMv4 */
+
+/* strobe feature */
+
+/* register defines */
+#define STRB_REG_CTR (CS_CFG_REG_RESOURCE | ETM4_CFG_RES_CTR)
+#define STRB_REG_CTR_RB (STRB_REG_CTR | CS_CFG_REG_VAL_SAVE)
+#define STRB_REG_CTR_PRM (STRB_REG_CTR | CS_CFG_REG_VAL_PARAM)
+#define STRB_REG_SEQ (CS_CFG_REG_RESOURCE | ETM4_CFG_RES_SEQ)
+#define STRB_REG_SEL (CS_CFG_REG_RESOURCE | ETM4_CFG_RES_SEL)
+#define STRB_REG_VI  (CS_CFG_REG_STD | CS_CFG_REG_VAL_MASK)
+
+static struct cscfg_parameter_desc strobe_params[] = {
+	{
+		.name = "window",
+		.value = 5000,
+	},
+	{
+		.name = "period",
+		.value = 10000,
+	},
+};
+
+static struct cscfg_regval strobe_regs[] = {
+	/* resource selectors */
+	{
+		.flags = STRB_REG_SEL | TRCRSCTLRn(2),
+		.val32 = 0x20001,
+	},
+	{
+		.flags = STRB_REG_SEQ | TRCRSCTLRn(3),
+		.val32 = 0x20002,
+	},
+	/* strobe window counter 0 - reload from param 0 */
+	{
+		.flags = STRB_REG_CTR_RB | TRCCNTVRn(0),
+	},
+	{
+		.flags = STRB_REG_CTR_PRM | TRCCNTRLDVRn(0),
+		.val32 = 0,
+	},
+	{
+		.flags = STRB_REG_CTR | TRCCNTCTLRn(0),
+		.val32 = 0x10001,
+	},
+	/* strobe period counter 1 - reload from param 1 */
+	{
+		.flags = STRB_REG_CTR_RB | TRCCNTVRn(1),
+	},
+	{
+		.flags = STRB_REG_CTR_PRM | TRCCNTRLDVRn(1),
+		.val32 = 1,
+	},
+	{
+		.flags = STRB_REG_CTR | TRCCNTCTLRn(1),
+		.val32 = 0x8102,
+	},
+	/* sequencer */
+	{
+		.flags = STRB_REG_SEQ | TRCSEQEVRn(0),
+		.val32 = 0x0081,
+	},
+	{
+		.flags = STRB_REG_SEQ | TRCSEQEVRn(1),
+		.val32 = 0x0000,
+	},
+	/* view-inst */
+	{
+		.flags = STRB_REG_VI | TRCVICTLR,
+		.val32 = 0x0003,
+		.mask32 = 0x0003,
+	},
+	/* end of regs */
+};
+
+static struct cscfg_feature_desc strobe = {
+	.name = "strobing",
+	.brief = "Generate periodic trace capture windows.\n"
+	"parameter \'window\': a number of CPU cycles (W)\n"
+	"parameter \'period\': trace enabled for W cycles every period x W cycles\n",
+	.match_flags = CS_CFG_MATCH_CLASS_SRC_ETM4,
+	.nr_params = ARRAY_SIZE(strobe_params),
+	.params = strobe_params,
+	.nr_regs = ARRAY_SIZE(strobe_regs),
+	.regs = strobe_regs,
+};
+
+static struct cscfg_feature_desc *preload_feats[] = {
+	&strobe,
+	0
+};
+
+/* create an autofdo configuration */
+
+/* we will provide 9 sets of preset parameter values */
+#define AFDO_NR_PRESETS		9
+/* the total number of parameters in used features */
+#define AFDO_NR_PARAM_SUM	ARRAY_SIZE(strobe_params)
+
+#define AFDO_MATCH_STROBING (CS_CFG_MATCH_INST_ANY | CS_CFG_MATCH_CLASS_SRC_ETM4)
+
+static struct cscfg_config_feat_ref afdo_refs[] = {
+	{
+		.name = "strobing",
+		.nr_params = ARRAY_SIZE(strobe_params),
+		.match = {
+			.match_flags = AFDO_MATCH_STROBING,
+		},
+	},
+};
+
+/*
+ * set of presets leaves strobing window constant while varying period to allow
+ * experimentation with mark / space ratios for various workloads
+ */
+static u64 afdo_presets[AFDO_NR_PRESETS][AFDO_NR_PARAM_SUM] = {
+	{ 5000, 2 },
+	{ 5000, 4 },
+	{ 5000, 8 },
+	{ 5000, 16 },
+	{ 5000, 64 },
+	{ 5000, 128 },
+	{ 5000, 512 },
+	{ 5000, 1024 },
+	{ 5000, 4096 },
+};
+
+static struct cscfg_config_desc afdo = {
+	.name = "autofdo",
+	.brief = "Setup ETMs with strobing for autofdo\n"
+	"Supplied presets allow experimentation with mark-space ratio for various loads\n",
+	.nr_refs = ARRAY_SIZE(afdo_refs),
+	.refs = afdo_refs,
+	.nr_presets = AFDO_NR_PRESETS,
+	.nr_total_params = AFDO_NR_PARAM_SUM,
+	.presets = &afdo_presets[0][0],
+};
+
+static struct cscfg_config_desc *preload_cfgs[] = {
+	&afdo,
+	0
+};
+
+/* preload called with mutex locked */
+int cscfg_preload(void)
+{
+	return cscfg_load_config_sets(preload_cfgs, preload_feats);
+}
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
index 481d2b7b6b6f..dca84b3f5fca 100644
--- a/drivers/hwtracing/coresight/coresight-core.c
+++ b/drivers/hwtracing/coresight/coresight-core.c
@@ -1680,9 +1680,15 @@ static int __init coresight_init(void)
 
 	/* initialise the coresight syscfg API */
 	ret = cscfg_init();
+	if (ret)
+		goto exit_perf_close;
+
+	/* preload builtin configurations */
+	ret = cscfg_preload();
 	if (!ret)
 		return 0;
 
+exit_perf_close:
 	etm_perf_exit();
 exit_bus_unregister:
 	bus_unregister(&coresight_bustype);
diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h
index ecf4aac7d712..e8f352599dd7 100644
--- a/drivers/hwtracing/coresight/coresight-syscfg.h
+++ b/drivers/hwtracing/coresight/coresight-syscfg.h
@@ -45,6 +45,7 @@ struct cscfg_csdev_register {
 /* internal core operations for cscfg */
 int __init cscfg_init(void);
 void __exit cscfg_exit(void);
+int cscfg_preload(void);
 
 /* syscfg external API */
 int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs,
-- 
2.17.1


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