[RFC PATCH v3 5/9] coresight: etm4x: Add complex configuration handlers to etmv4
Mathieu Poirier
mathieu.poirier at linaro.org
Mon Nov 23 16:58:20 EST 2020
On Fri, Oct 30, 2020 at 05:56:51PM +0000, Mike Leach wrote:
> Adds in handlers to allow the ETMv4 to use the complex configuration
> support. Features and configurations can be loaded and selected in the
> device.
>
> Signed-off-by: Mike Leach <mike.leach at linaro.org>
> ---
> drivers/hwtracing/coresight/Makefile | 3 +-
> .../hwtracing/coresight/coresight-etm4x-cfg.c | 181 ++++++++++++++++++
> .../hwtracing/coresight/coresight-etm4x-cfg.h | 29 +++
> .../coresight/coresight-etm4x-core.c | 36 +++-
> .../coresight/coresight-etm4x-sysfs.c | 3 +
> 5 files changed, 249 insertions(+), 3 deletions(-)
> create mode 100644 drivers/hwtracing/coresight/coresight-etm4x-cfg.c
> create mode 100644 drivers/hwtracing/coresight/coresight-etm4x-cfg.h
>
> diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
> index daad9f103a78..ea544206204d 100644
> --- a/drivers/hwtracing/coresight/Makefile
> +++ b/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
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-cfg.c b/drivers/hwtracing/coresight/coresight-etm4x-cfg.c
> new file mode 100644
> index 000000000000..9589d43e7947
> --- /dev/null
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-cfg.c
> @@ -0,0 +1,181 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright(C) 2020 Linaro Limited. All rights reserved.
> + * Author: Mike Leach <mike.leach at linaro.org>
> + */
> +
> +#include "coresight-etm4x.h"
> +#include "coresight-etm4x-cfg.h"
> +#include "coresight-priv.h"
> +#include "coresight-syscfg.h"
> +
> +/**
> + * 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_reg_csdev *reg, u32 offset)
> +{
> + int err = -EINVAL, idx;
> + struct etmv4_config *drvcfg = &drvdata->config;
> + u32 off_mask;
> +
> +#define CHECKREG(cval, elem) \
> + { \
> + if (offset == cval) { \
> + reg->drv_store = &drvcfg->elem; \
> + err = 0; \
> + break; \
> + } \
> + }
> +
> +#define CHECKREGIDX(cval, elem, off_idx) \
> + { \
> + if (off_mask == cval) { \
> + reg->drv_store = &drvcfg->elem[off_idx]; \
> + err = 0; \
> + break; \
> + } \
> + }
> +
> + 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->drv_store = &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);
> + CHECKREGIDX(TRCSSCSRn(0), ss_status, idx);
> + CHECKREGIDX(TRCSSPCICRn(0), ss_pe_cmp, idx);
This one is harder to understand because of @off_mask - please add it to the
list of parameters to the marcro so that all the element needed to understand
what is going on is at the same place.
> + } 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);
> + CHECKREGIDX(TRCVMIDCVRn(0), vmid_val, idx);
> + } 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->drv_store = &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);
> + CHECKREGIDX(TRCACATRn(0), addr_acc, idx);
> + } 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);
> + CHECKREGIDX(TRCCNTCTLRn(0), cntr_ctrl, idx);
> + CHECKREGIDX(TRCCNTVRn(0), cntr_val, idx);
> + } 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)
> +{
> + struct device *dev = csdev->dev.parent;
> + struct etmv4_drvdata *drvdata = dev_get_drvdata(dev);
> + const struct cscfg_feature_desc *feat_desc = feat->desc;
> + u32 offset;
> + int i = 0, err = 0;
> +
> + /* essential we set the device spinlock */
Please explain why you are doing this. Otherwise we know it has to be done but
still wonder about the motivation.
> + feat->csdev_spinlock = &drvdata->spinlock;
> +
> + /* process the register descriptions */
> + for (i = 0; i < feat->nr_regs && !err; i++) {
> + offset = feat_desc->regs[i].flags & CS_CFG_REG_ID_MASK;
This confirms my comment from a previous patch. Embedding the offset
in a variable called "flags" is very confusing.
> + err = etm4_cfg_map_reg_offset(drvdata, &feat->regs[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_cs_cfg_register(struct coresight_device *csdev, const char *dev_name)
> +{
s/etm4_cs_cfg_register/etm4_cscfg_register()
> + struct cscfg_match_info cfg_info;
> + struct cscfg_csdev_feat_ops ops;
> +
> + cfg_info.dev_name = dev_name;
> + cfg_info.match_flags = CS_CFG_ETM4_MATCH_FLAGS;
> +
> + ops.load_feat = &etm4_cfg_load_feature;
> +
> + return cscfg_register_csdev(csdev, &cfg_info, &ops);
> +}
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-cfg.h b/drivers/hwtracing/coresight/coresight-etm4x-cfg.h
> new file mode 100644
> index 000000000000..bf33c720b5e9
> --- /dev/null
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-cfg.h
> @@ -0,0 +1,29 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2014-2015, The Linux Foundation. All rights reserved.
> + */
> +
> +#ifndef _CORESIGHT_CORESIGHT_ETM4X_CFG_H
> +#define _CORESIGHT_CORESIGHT_ETM4X_CFG_H
> +
> +#include "coresight-config.h"
> +#include "coresight-etm4x.h"
> +
> +/* ETMv4 specific config defines */
> +
> +/* resource IDs */
> +
> +#define ETM4_CFG_RES_CTR 0x00001000
> +#define ETM4_CFG_RES_CMP 0x00002000
> +#define ETM4_CFG_RES_CMP_PAIR0 0x00003000
> +#define ETM4_CFG_RES_CMP_PAIR1 0x00004000
> +#define ETM4_CFG_RES_SEL 0x00005000
> +#define ETM4_CFG_RES_SEL_PAIR0 0x00006000
> +#define ETM4_CFG_RES_SEL_PAIR1 0x00007000
> +#define ETM4_CFG_RES_SEQ 0x00008000
> +#define ETM4_CFG_RES_TS 0x00009000
> +#define ETM4_CFG_RES_MASK 0x0000F000
> +
The first #define is used in the next patch but none of the others are.
> +int etm4_cs_cfg_register(struct coresight_device *csdev, const char *dev_name);
> +
> +#endif /* _CORESIGHT_CORESIGHT_ETM4X_CFG_H */
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> index 6096d7abf80d..88213aa7a72e 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
> +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
> @@ -34,6 +34,8 @@
>
> #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);
> @@ -321,12 +323,15 @@ static int etm4_config_timestamp_event(struct etmv4_drvdata *drvdata)
> 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_id;
> + int preset;
>
> if (!attr) {
> ret = -EINVAL;
> @@ -384,6 +389,19 @@ 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.
> + */
> + if (attr->config2 & GENMASK_ULL(63, 32)) {
I understand why you have used a mask of 63-32 but it would be extremely cryptic
for anyone else. Please add a comment that justify your choice.
> + cfg_id = (u32)(attr->config2 >> 32);
> + preset = attr->config & 0xF;
This implies that presets need to start at 1 rather than 0. Otherwise there is
no way to specify the absence of a preset. There is a comment for
cscfg_csdev_enable_config() but adding another one here to complete the equation
would be appreciated.
> + ret = cscfg_csdev_enable_config(csdev, cfg_id, preset);
> + }
> +
> out:
> return ret;
> }
> @@ -400,7 +418,7 @@ 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 */
> @@ -416,6 +434,8 @@ static int etm4_enable_sysfs(struct coresight_device *csdev)
> struct etm4_enable_arg arg = { };
> int ret;
>
> + cscfg_csdev_set_enabled_feats(csdev);
> +
> spin_lock(&drvdata->spinlock);
>
> /*
> @@ -530,11 +550,14 @@ 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);
> + if (attr->config2 & GENMASK_ULL(63, 32))
Here too.
I will continue tomorrow.
Thanks,
Mathieu
> + cscfg_csdev_disable_config(csdev);
>
> /*
> * Check if the start/stop logic was active when the unit was stopped.
> @@ -569,6 +592,7 @@ static void etm4_disable_sysfs(struct coresight_device *csdev)
> smp_call_function_single(drvdata->cpu, etm4_disable_hw, drvdata, 1);
>
> spin_unlock(&drvdata->spinlock);
> + cscfg_csdev_save_enabled_feats(csdev);
> cpus_read_unlock();
>
> dev_dbg(&csdev->dev, "ETM tracing disabled\n");
> @@ -1536,6 +1560,13 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
> return ret;
> }
>
> + /* register with config infrastructure & load any current features */
> + ret = etm4_cs_cfg_register(drvdata->csdev, dev_name(dev));
> + if (ret) {
> + coresight_unregister(drvdata->csdev);
> + return ret;
> + }
> +
> etmdrvdata[drvdata->cpu] = drvdata;
>
> pm_runtime_put(&adev->dev);
> @@ -1588,6 +1619,7 @@ static int __exit etm4_remove(struct amba_device *adev)
>
> cpus_read_unlock();
>
> + cscfg_unregister_csdev(drvdata->csdev);
> coresight_unregister(drvdata->csdev);
>
> return 0;
> diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
> index 989ce7b8ade7..78e68f3032d5 100644
> --- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
> +++ b/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-config.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);
> --
> 2.17.1
>
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