[RFC PATCH v3 6/9] coresight: config: Add preloaded configurations
Mike Leach
mike.leach at linaro.org
Fri Oct 30 13:56:52 EDT 2020
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 at 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 at 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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