Re: [PATCH 03/10] Coresight: Add driver to support Coresight device TPDM
From: Jinlong
Date: Fri Nov 05 2021 - 04:15:45 EST
Good afternoon.
On Thu, Nov 04, 2021 at 10:55:04AM -0600, Mathieu Poirier wrote:
> [...]
>
> >
> > > > +
> > > > +#ifdef CONFIG_CORESIGHT_TPDM_DEFAULT_ENABLE
> > > > +static int boot_enable = 1;
> > > > +#else
> > > > +static int boot_enable;
> > > > +#endif
> > >
> > > That isn't the proper way to do this. Look at how it is done in
> > > coresight-etm4x.c
> > >
> > > > +
> > > > +struct gpr_dataset {
> > > > + DECLARE_BITMAP(gpr_dirty, TPDM_GPR_REGS_MAX);
> > > > + uint32_t gp_regs[TPDM_GPR_REGS_MAX];
> > >
> > > Shouldn't this be u32?
> > >
> >
> > uint32_t is the same as u32.
> > typedef u32 uint32_t;
>
> Right - but the common kernel convention is to use u64/32/16/8. Please refactor
> for the entire patchset.
>
We will address your comments.
> >
> > > > +};
> > > > +
> > > > +struct bc_dataset {
> > > > + enum tpdm_mode capture_mode;
> > > > + enum tpdm_mode retrieval_mode;
> > > > + uint32_t sat_mode;
> > > > + uint32_t enable_counters;
> > > > + uint32_t clear_counters;
> > > > + uint32_t enable_irq;
> > > > + uint32_t clear_irq;
> > > > + uint32_t trig_val_lo[TPDM_BC_MAX_COUNTERS];
> > > > + uint32_t trig_val_hi[TPDM_BC_MAX_COUNTERS];
> > > > + uint32_t enable_ganging;
> > > > + uint32_t overflow_val[TPDM_BC_MAX_OVERFLOW];
> > > > + uint32_t msr[TPDM_BC_MAX_MSR];
> > > > +};
> > > > +
> > > > +struct tc_dataset {
> > > > + enum tpdm_mode capture_mode;
> > > > + enum tpdm_mode retrieval_mode;
> > > > + bool sat_mode;
> > > > + uint32_t enable_counters;
> > > > + uint32_t clear_counters;
> > > > + uint32_t enable_irq;
> > > > + uint32_t clear_irq;
> > > > + uint32_t trig_sel[TPDM_TC_MAX_TRIG];
> > > > + uint32_t trig_val_lo[TPDM_TC_MAX_TRIG];
> > > > + uint32_t trig_val_hi[TPDM_TC_MAX_TRIG];
> > > > + uint32_t msr[TPDM_TC_MAX_MSR];
> > > > +};
> > > > +
> > > > +struct dsb_dataset {
> > > > + uint32_t mode;
> > > > + uint32_t edge_ctrl[TPDM_DSB_MAX_EDCR];
> > > > + uint32_t edge_ctrl_mask[TPDM_DSB_MAX_EDCR / 2];
> > > > + uint32_t patt_val[TPDM_DSB_MAX_PATT];
> > > > + uint32_t patt_mask[TPDM_DSB_MAX_PATT];
> > > > + bool patt_ts;
> > > > + bool patt_type;
> > > > + uint32_t trig_patt_val[TPDM_DSB_MAX_PATT];
> > > > + uint32_t trig_patt_mask[TPDM_DSB_MAX_PATT];
> > > > + bool trig_ts;
> > > > + bool trig_type;
> > > > + uint32_t select_val[TPDM_DSB_MAX_SELECT];
> > > > + uint32_t msr[TPDM_DSB_MAX_MSR];
> > > > +};
> > > > +
> > > > +struct mcmb_dataset {
> > > > + uint8_t mcmb_trig_lane;
> > > > + uint8_t mcmb_lane_select;
> > > > +};
> > > > +
> > > > +struct cmb_dataset {
> > > > + bool trace_mode;
> > > > + uint32_t cycle_acc;
> > > > + uint32_t patt_val[TPDM_CMB_PATT_CMP];
> > > > + uint32_t patt_mask[TPDM_CMB_PATT_CMP];
> > > > + bool patt_ts;
> > > > + uint32_t trig_patt_val[TPDM_CMB_PATT_CMP];
> > > > + uint32_t trig_patt_mask[TPDM_CMB_PATT_CMP];
> > > > + bool trig_ts;
> > > > + bool ts_all;
> > > > + uint32_t msr[TPDM_CMB_MAX_MSR];
> > > > + uint8_t read_ctl_reg;
> > > > + struct mcmb_dataset *mcmb;
> > > > +};
> > > > +
> > > > +DEFINE_CORESIGHT_DEVLIST(tpdm_devs, "tpdm");
> > > > +
> > > > +struct tpdm_drvdata {
> > > > + void __iomem *base;
> > > > + struct device *dev;
> > > > + struct coresight_device *csdev;
> > > > + int nr_tclk;
> > > > + struct clk **tclk;
> > > > + int nr_treg;
> > > > + struct regulator **treg;
> > > > + struct mutex lock;
> > > > + bool enable;
> > > > + bool clk_enable;
> > > > + DECLARE_BITMAP(datasets, TPDM_DATASETS);
> > > > + DECLARE_BITMAP(enable_ds, TPDM_DATASETS);
> > > > + enum tpdm_support_type tc_trig_type;
> > > > + enum tpdm_support_type bc_trig_type;
> > > > + enum tpdm_support_type bc_gang_type;
> > > > + uint32_t bc_counters_avail;
> > > > + uint32_t tc_counters_avail;
> > > > + struct gpr_dataset *gpr;
> > > > + struct bc_dataset *bc;
> > > > + struct tc_dataset *tc;
> > > > + struct dsb_dataset *dsb;
> > > > + struct cmb_dataset *cmb;
> > > > + int traceid;
> > > > + uint32_t version;
> > > > + bool msr_support;
> > > > + bool msr_fix_req;
> > > > + bool cmb_msr_skip;
> > > > +};
> > >
> > > All of these should also be in a header file and properly documented.
> > >
> >
> > We will move these to header file and add the documentation.
> >
> > > > +
> > > > +static void tpdm_init_default_data(struct tpdm_drvdata *drvdata);
> > >
> > > This isn't needed.
> >
> > We will remove this.
> > >
> > > > +
> > > > +static void __tpdm_enable(struct tpdm_drvdata *drvdata)
> > > > +{
> > > > + TPDM_UNLOCK(drvdata);
> > > > +
> > > > + if (drvdata->clk_enable)
> > > > + tpdm_writel(drvdata, 0x1, TPDM_CLK_CTRL);
> > > > +
> > > > + TPDM_LOCK(drvdata);
> > > > +}
> > > > +
> > > > +static int tpdm_enable(struct coresight_device *csdev,
> > > > + struct perf_event *event, u32 mode)
> > > > +{
> > > > + struct tpdm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
> > > > + int ret = 0;
> > > > +
> > > > + if (drvdata->enable) {
> > >
> > > This a race condition.
> > >
> >
> > Need to add it to mutex_lock. We will update.
> >
> > > > + dev_err(drvdata->dev,
> > > > + "TPDM setup already enabled,Skipping enablei\n");
> > >
> > > Please remove this.
> > >
> >
> > We will remove this.
> >
> > > > + return ret;
> > >
> > > Shouldn't this be return -EBUSY?
> >
> > We will address your comments.
> >
> > >
> > > > + }
> > > > +
> > > > + mutex_lock(&drvdata->lock);
> > > > + __tpdm_enable(drvdata);
> > > > + drvdata->enable = true;
> > > > + mutex_unlock(&drvdata->lock);
> > > > +
> > > > + dev_info(drvdata->dev, "TPDM tracing enabled\n");
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static void __tpdm_disable(struct tpdm_drvdata *drvdata)
> > > > +{
> > > > + TPDM_UNLOCK(drvdata);
> > > > +
> > > > + if (drvdata->clk_enable)
> > > > + tpdm_writel(drvdata, 0x0, TPDM_CLK_CTRL);
> > > > +
> > > > + TPDM_LOCK(drvdata);
> > > > +}
> > > > +
> > > > +static void tpdm_disable(struct coresight_device *csdev,
> > > > + struct perf_event *event)
> > > > +{
> > > > + struct tpdm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
> > > > +
> > > > + if (!drvdata->enable) {
> > > > + dev_err(drvdata->dev,
> > > > + "TPDM setup already disabled, Skipping disable\n");
> > > > + return;
> > > > + }
> > > > + mutex_lock(&drvdata->lock);
> > > > + __tpdm_disable(drvdata);
> > > > + drvdata->enable = false;
> > > > + mutex_unlock(&drvdata->lock);
> > >
> > > Same comments as above.
> > >
> >
> > We will address your comments.
> >
> > > > +
> > > > + dev_info(drvdata->dev, "TPDM tracing disabled\n");
> > > > +}
> > > > +
> > > > +static int tpdm_trace_id(struct coresight_device *csdev)
> > > > +{
> > > > + struct tpdm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
> > > > +
> > > > + return drvdata->traceid;
> > > > +}
> > > > +
> > > > +static const struct coresight_ops_source tpdm_source_ops = {
> > > > + .trace_id = tpdm_trace_id,
> > > > + .enable = tpdm_enable,
> > > > + .disable = tpdm_disable,
> > > > +};
> > > > +
> > > > +static const struct coresight_ops tpdm_cs_ops = {
> > > > + .source_ops = &tpdm_source_ops,
> > > > +};
> > > > +
> > > > +static int tpdm_datasets_alloc(struct tpdm_drvdata *drvdata)
> > > > +{
> > > > + if (test_bit(TPDM_DS_GPR, drvdata->datasets)) {
> > > > + drvdata->gpr = devm_kzalloc(drvdata->dev, sizeof(*drvdata->gpr),
> > > > + GFP_KERNEL);
> > > > + if (!drvdata->gpr)
> > > > + return -ENOMEM;
> > > > + }
> > > > + if (test_bit(TPDM_DS_BC, drvdata->datasets)) {
> > > > + drvdata->bc = devm_kzalloc(drvdata->dev, sizeof(*drvdata->bc),
> > > > + GFP_KERNEL);
> > > > + if (!drvdata->bc)
> > > > + return -ENOMEM;
> > > > + }
> > > > + if (test_bit(TPDM_DS_TC, drvdata->datasets)) {
> > > > + drvdata->tc = devm_kzalloc(drvdata->dev, sizeof(*drvdata->tc),
> > > > + GFP_KERNEL);
> > > > + if (!drvdata->tc)
> > > > + return -ENOMEM;
> > > > + }
> > > > + if (test_bit(TPDM_DS_DSB, drvdata->datasets)) {
> > > > + drvdata->dsb = devm_kzalloc(drvdata->dev, sizeof(*drvdata->dsb),
> > > > + GFP_KERNEL);
> > > > + if (!drvdata->dsb)
> > > > + return -ENOMEM;
> > > > + }
> > > > + if (test_bit(TPDM_DS_CMB, drvdata->datasets)) {
> > > > + drvdata->cmb = devm_kzalloc(drvdata->dev, sizeof(*drvdata->cmb),
> > > > + GFP_KERNEL);
> > > > + if (!drvdata->cmb)
> > > > + return -ENOMEM;
> > > > + } else if (test_bit(TPDM_DS_MCMB, drvdata->datasets)) {
> > > > + drvdata->cmb = devm_kzalloc(drvdata->dev, sizeof(*drvdata->cmb),
> > > > + GFP_KERNEL);
> > > > + if (!drvdata->cmb)
> > > > + return -ENOMEM;
> > > > + drvdata->cmb->mcmb = devm_kzalloc(drvdata->dev,
> > > > + sizeof(*drvdata->cmb->mcmb),
> > > > + GFP_KERNEL);
> > > > + if (!drvdata->cmb->mcmb)
> > > > + return -ENOMEM;
> > >
> > > How can I understand what the above does when:
> > >
> > > 1) There isn't a single line of comments.
> > > 2) I don't know the HW.
> > > 3) I don't have access to the documentation.
> > >
> >
> > We will add comments here.
> >
> > > > + }
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static void tpdm_init_default_data(struct tpdm_drvdata *drvdata)
> > > > +{
> > > > + if (test_bit(TPDM_DS_BC, drvdata->datasets))
> > > > + drvdata->bc->retrieval_mode = TPDM_MODE_ATB;
> > > > +
> > > > + if (test_bit(TPDM_DS_TC, drvdata->datasets))
> > > > + drvdata->tc->retrieval_mode = TPDM_MODE_ATB;
> > > > +
> > > > + if (test_bit(TPDM_DS_DSB, drvdata->datasets)) {
> > > > + drvdata->dsb->trig_ts = true;
> > > > + drvdata->dsb->trig_type = false;
> > > > + }
> > > > +
> > > > + if (test_bit(TPDM_DS_CMB, drvdata->datasets) ||
> > > > + test_bit(TPDM_DS_MCMB, drvdata->datasets))
> > > > + drvdata->cmb->trig_ts = true;
> > > > +}
> > > > +
> > > > +static int tpdm_parse_of_data(struct tpdm_drvdata *drvdata)
> > > > +{
> > > > + int i, ret;
> > > > + const char *tclk_name, *treg_name;
> > > > + struct device_node *node = drvdata->dev->of_node;
> > > > +
> > > > + drvdata->clk_enable = of_property_read_bool(node, "qcom,clk-enable");
> > > > + drvdata->msr_fix_req = of_property_read_bool(node, "qcom,msr-fix-req");
> > > > + drvdata->cmb_msr_skip = of_property_read_bool(node,
> > > > + "qcom,cmb-msr-skip");
> > > > +
> > > > + drvdata->nr_tclk = of_property_count_strings(node, "qcom,tpdm-clks");
> > > > + if (drvdata->nr_tclk > 0) {
> > > > + drvdata->tclk = devm_kzalloc(drvdata->dev, drvdata->nr_tclk *
> > > > + sizeof(*drvdata->tclk),
> > > > + GFP_KERNEL);
> > > > + if (!drvdata->tclk)
> > > > + return -ENOMEM;
> > > > +
> > > > + for (i = 0; i < drvdata->nr_tclk; i++) {
> > > > + ret = of_property_read_string_index(node,
> > > > + "qcom,tpdm-clks", i, &tclk_name);
> > > > + if (ret)
> > > > + return ret;
> > > > +
> > > > + drvdata->tclk[i] = devm_clk_get(drvdata->dev,
> > > > + tclk_name);
> > > > + if (IS_ERR(drvdata->tclk[i]))
> > > > + return PTR_ERR(drvdata->tclk[i]);
> > > > + }
> > > > + }
> > > > +
> > > > + drvdata->nr_treg = of_property_count_strings(node, "qcom,tpdm-regs");
> > > > + if (drvdata->nr_treg > 0) {
> > > > + drvdata->treg = devm_kzalloc(drvdata->dev, drvdata->nr_treg *
> > > > + sizeof(*drvdata->treg),
> > > > + GFP_KERNEL);
> > > > + if (!drvdata->treg)
> > > > + return -ENOMEM;
> > > > +
> > > > + for (i = 0; i < drvdata->nr_treg; i++) {
> > > > + ret = of_property_read_string_index(node,
> > > > + "qcom,tpdm-regs", i, &treg_name);
> > > > + if (ret)
> > > > + return ret;
> > > > +
> > > > + drvdata->treg[i] = devm_regulator_get(drvdata->dev,
> > > > + treg_name);
> > > > + if (IS_ERR(drvdata->treg[i]))
> > > > + return PTR_ERR(drvdata->treg[i]);
> > > > + }
> > > > + }
> > >
> > > _None_ of the above are defined in the yaml file and/or part of the example that
> > > is shown there. Moreover they don't appear in patch 10/10 where TPDM and TPDA are
> > > supposed to be introduced. I will comment on patch 10/10 when I'm done with
> > > this one.
> > >
> >
> > We will update the dtsi change in next version.
> >
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static int tpdm_probe(struct amba_device *adev, const struct amba_id *id)
> > > > +{
> > > > + int ret, i;
> > > > + uint32_t pidr, devid;
> > > > + struct device *dev = &adev->dev;
> > > > + struct coresight_platform_data *pdata;
> > > > + struct tpdm_drvdata *drvdata;
> > > > + struct coresight_desc desc = { 0 };
> > > > + static int traceid = TPDM_TRACE_ID_START;
> > > > + uint32_t version;
> > > > +
> > > > + desc.name = coresight_alloc_device_name(&tpdm_devs, dev);
> > > > + if (!desc.name)
> > > > + return -ENOMEM;
> > > > + pdata = coresight_get_platform_data(dev);
> > > > + if (IS_ERR(pdata))
> > > > + return PTR_ERR(pdata);
> > > > + adev->dev.platform_data = pdata;
> > > > +
> > > > + drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
> > > > + if (!drvdata)
> > > > + return -ENOMEM;
> > > > + drvdata->dev = &adev->dev;
> > > > + dev_set_drvdata(dev, drvdata);
> > > > +
> > > > + drvdata->base = devm_ioremap_resource(dev, &adev->res);
> > > > + if (!drvdata->base)
> > > > + return -ENOMEM;
> > > > +
> > > > + mutex_init(&drvdata->lock);
> > > > +
> > > > + ret = tpdm_parse_of_data(drvdata);
> > > > + if (ret) {
> > > > + dev_err(drvdata->dev, "TPDM parse of data fail\n");
> > > > + return -EINVAL;
> > > > + }
> > > > +
> > > > + desc.type = CORESIGHT_DEV_TYPE_SOURCE;
> > > > + desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_PROC;
> > >
> > > Why is this of subtype CORESIGHT_DEV_SUBTYPE_SOURCE_PROC when TPDMs are not
> > > associated with a CPU? Here we should probably introduce something like
> > > CORESIGHT_DEV_SUBTYPE_SOURCE_SYS
> >
> >
> > We will check and update.
> >
> > >
> > > > + desc.ops = &tpdm_cs_ops;
> > > > + desc.pdata = adev->dev.platform_data;
> > > > + desc.dev = &adev->dev;
> > > > + drvdata->csdev = coresight_register(&desc);
> > > > + if (IS_ERR(drvdata->csdev))
> > > > + return PTR_ERR(drvdata->csdev);
> > > > +
> > > > + version = tpdm_readl(drvdata, CORESIGHT_PERIPHIDR2);
> > > > + drvdata->version = BMVAL(version, 4, 7);
> > > > +
> > >
> > > What is MSR support? This should be documented. Looking more closely at this
> > > patch, not a single line of documentation is provided. If you look at other
> > > drivers, you will find things to be quite different. The coresight subsystem
> > > has become very complex and documentation helps us, and anyone trying to
> > > contribute, understand what the code does.
> > >
> >
> > We will add more documentation in the driver.
> >
> >
> > > > + if (drvdata->version)
> > > > + drvdata->msr_support = true;
> > > > +
> > > > + pidr = tpdm_readl(drvdata, CORESIGHT_PERIPHIDR0);
> > > > + for (i = 0; i < TPDM_DATASETS; i++) {
> > > > + if (pidr & BIT(i)) {
> > > > + __set_bit(i, drvdata->datasets);
> > > > + __set_bit(i, drvdata->enable_ds);
> > > > + }
> > > > + }
> > > > +
> > > > + ret = tpdm_datasets_alloc(drvdata);
> > > > + if (ret) {
> > > > + coresight_unregister(drvdata->csdev);
> > > > + return ret;
> > > > + }
> > > > +
> > > > + tpdm_init_default_data(drvdata);
> > > > +
> > > > + devid = tpdm_readl(drvdata, CORESIGHT_DEVID);
> > > > + drvdata->tc_trig_type = BMVAL(devid, 27, 28);
> > > > + drvdata->bc_trig_type = BMVAL(devid, 25, 26);
> > > > + drvdata->bc_gang_type = BMVAL(devid, 23, 24);
> > > > + drvdata->bc_counters_avail = BMVAL(devid, 6, 10) + 1;
> > > > + drvdata->tc_counters_avail = BMVAL(devid, 4, 5) + 1;
> > >
> > > Shouldn't this be part of tpdm_init_default_data()?
> > >
> >
> > We will address your comments.
> >
> > > > +
> > > > + drvdata->traceid = traceid++;
> > >
> > > For this to work a new function needs to be introduced in coresight-pmu.h.
> > > Something like:
> > >
> > > static inline int coresight_get_system_trace_id(int id)
> > > {
> > > /* Start system IDs above the highest per CPU trace ID. */
> > > return coresigth_get_trace_id(cpumask_last(cpu_possible_mask) + 1);
> > > }
> > >
> >
> > We will address your comments.
> >
> > > > +
> > > > + dev_dbg(drvdata->dev, "TPDM initialized\n");
> > >
> > > Please remove this.
> > >
> >
> > We will remove it.
> >
> > > > +
> > > > + if (boot_enable)
> > > > + coresight_enable(drvdata->csdev);
> > > > +
> > > > + pm_runtime_put(&adev->dev);
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static struct amba_id tpdm_ids[] = {
> > > > + {
> > > > + .id = 0x001f0e00,
> > > > + .mask = 0x00ffff00,
> > >
> > > Any way we can use CS_AMBA_ID() here?
> > >
> >
> > We will address your comments.
> >
> > > > + .data = "TPDM",
> > >
> > > What is .data used for?
> >
> > It is just to fill the structure. We will remove it if it is not necessary.
> >
> > >
> > > > + },
> > > > + { 0, 0},
> > > > +};
> > > > +
> > > > +static struct amba_driver tpdm_driver = {
> > > > + .drv = {
> > > > + .name = "coresight-tpdm",
> > > > + .owner = THIS_MODULE,
> > > > + .suppress_bind_attrs = true,
> > > > + },
> > > > + .probe = tpdm_probe,
> > > > + .id_table = tpdm_ids,
> > > > +};
> > > > +
> > > > +module_amba_driver(tpdm_driver);
> > > > +
> > > > +MODULE_LICENSE("GPL v2");
> > > > +MODULE_DESCRIPTION("Trace, Profiling & Diagnostic Monitor driver");
> > > > --
> > > > 2.17.1
> > > >