diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c index a128b5063f46..4cecabdd051b 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.c +++ b/drivers/hwtracing/coresight/coresight-etm4x.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -26,6 +27,7 @@ #include #include #include +#include #include #include #include @@ -37,6 +39,15 @@ static int boot_enable; module_param(boot_enable, int, 0444); MODULE_PARM_DESC(boot_enable, "Enable tracing on boot"); +#define PARAM_PM_SAVE_FIRMWARE 0 /* save self-hosted state as per firmware */ +#define PARAM_PM_SAVE_NEVER 1 /* never save any state */ +#define PARAM_PM_SAVE_SELF_HOSTED 2 /* save self-hosted state only */ + +static int pm_save_enable = PARAM_PM_SAVE_FIRMWARE; +module_param(pm_save_enable, int, 0444); +MODULE_PARM_DESC(pm_save_enable, + "Save/restore state on power down: 1 = never, 2 = self-hosted"); + /* The number of ETMv4 currently registered */ static int etm4_count; static struct etmv4_drvdata *etmdrvdata[NR_CPUS]; @@ -54,6 +65,14 @@ static void etm4_os_unlock(struct etmv4_drvdata *drvdata) isb(); } +static void etm4_os_lock(struct etmv4_drvdata *drvdata) +{ + /* Writing 0x1 to TRCOSLAR locks the trace registers */ + writel_relaxed(0x1, drvdata->base + TRCOSLAR); + drvdata->os_unlock = false; + isb(); +} + static bool etm4_arch_supported(u8 arch) { /* Mask out the minor version number */ @@ -1085,6 +1104,288 @@ static void etm4_init_trace_id(struct etmv4_drvdata *drvdata) drvdata->trcid = coresight_get_trace_id(drvdata->cpu); } +#ifdef CONFIG_CPU_PM +static int etm4_cpu_save(struct etmv4_drvdata *drvdata) +{ + int i, ret = 0; + struct etmv4_save_state *state; + struct device *etm_dev = &drvdata->csdev->dev; + + /* + * As recommended by 3.4.1 ("The procedure when powering down the PE") + * of ARM IHI 0064D + */ + dsb(sy); + isb(); + + CS_UNLOCK(drvdata->base); + + /* Lock the OS lock to disable trace and external debugger access */ + etm4_os_lock(drvdata); + + /* wait for TRCSTATR.PMSTABLE to go up */ + if (coresight_timeout(drvdata->base, TRCSTATR, + TRCSTATR_PMSTABLE_BIT, 1)) { + dev_err(etm_dev, + "timeout while waiting for PM Stable Status\n"); + etm4_os_unlock(drvdata); + ret = -EBUSY; + goto out; + } + + state = drvdata->save_state; + + state->trcprgctlr = readl(drvdata->base + TRCPRGCTLR); + state->trcprocselr = readl(drvdata->base + TRCPROCSELR); + state->trcconfigr = readl(drvdata->base + TRCCONFIGR); + state->trcauxctlr = readl(drvdata->base + TRCAUXCTLR); + state->trceventctl0r = readl(drvdata->base + TRCEVENTCTL0R); + state->trceventctl1r = readl(drvdata->base + TRCEVENTCTL1R); + state->trcstallctlr = readl(drvdata->base + TRCSTALLCTLR); + state->trctsctlr = readl(drvdata->base + TRCTSCTLR); + state->trcsyncpr = readl(drvdata->base + TRCSYNCPR); + state->trcccctlr = readl(drvdata->base + TRCCCCTLR); + state->trcbbctlr = readl(drvdata->base + TRCBBCTLR); + state->trctraceidr = readl(drvdata->base + TRCTRACEIDR); + state->trcqctlr = readl(drvdata->base + TRCQCTLR); + + state->trcvictlr = readl(drvdata->base + TRCVICTLR); + state->trcviiectlr = readl(drvdata->base + TRCVIIECTLR); + state->trcvissctlr = readl(drvdata->base + TRCVISSCTLR); + state->trcvipcssctlr = readl(drvdata->base + TRCVIPCSSCTLR); + state->trcvdctlr = readl(drvdata->base + TRCVDCTLR); + state->trcvdsacctlr = readl(drvdata->base + TRCVDSACCTLR); + state->trcvdarcctlr = readl(drvdata->base + TRCVDARCCTLR); + + for (i = 0; i < drvdata->nrseqstate; i++) + state->trcseqevr[i] = readl(drvdata->base + TRCSEQEVRn(i)); + + state->trcseqrstevr = readl(drvdata->base + TRCSEQRSTEVR); + state->trcseqstr = readl(drvdata->base + TRCSEQSTR); + state->trcextinselr = readl(drvdata->base + TRCEXTINSELR); + + for (i = 0; i < drvdata->nr_cntr; i++) { + state->trccntrldvr[i] = readl(drvdata->base + TRCCNTRLDVRn(i)); + state->trccntctlr[i] = readl(drvdata->base + TRCCNTCTLRn(i)); + state->trccntvr[i] = readl(drvdata->base + TRCCNTVRn(i)); + } + + for (i = 0; i < drvdata->nr_resource * 2; i++) + state->trcrsctlr[i] = readl(drvdata->base + TRCRSCTLRn(i)); + + for (i = 0; i < drvdata->nr_ss_cmp; i++) { + state->trcssccr[i] = readl(drvdata->base + TRCSSCCRn(i)); + state->trcsscsr[i] = readl(drvdata->base + TRCSSCSRn(i)); + state->trcsspcicr[i] = readl(drvdata->base + TRCSSPCICRn(i)); + } + + for (i = 0; i < drvdata->nr_addr_cmp * 2; i++) { + state->trcacvr[i] = readl(drvdata->base + TRCACVRn(i)); + state->trcacatr[i] = readl(drvdata->base + TRCACATRn(i)); + } + + /* + * Data trace stream is architecturally prohibited for A profile cores + * so we don't save (or later restore) trcdvcvr and trcdvcmr - As per + * section 1.3.4 ("Possible functional configurations of an ETMv4 trace + * unit") of ARM IHI 0064D. + */ + + for (i = 0; i < drvdata->numcidc; i++) + state->trccidcvr[i] = readl(drvdata->base + TRCCIDCVRn(i)); + + for (i = 0; i < drvdata->numvmidc; i++) + state->trcvmidcvr[i] = readl(drvdata->base + TRCVMIDCVRn(i)); + + state->trccidcctlr0 = readl(drvdata->base + TRCCIDCCTLR0); + state->trccidcctlr1 = readl(drvdata->base + TRCCIDCCTLR1); + + state->trcvmidcctlr0 = readl(drvdata->base + TRCVMIDCCTLR0); + state->trcvmidcctlr0 = readl(drvdata->base + TRCVMIDCCTLR1); + + state->trcclaimset = readl(drvdata->base + TRCCLAIMCLR); + + state->trcpdcr = readl(drvdata->base + TRCPDCR); + + /* wait for TRCSTATR.IDLE to go up */ + if (coresight_timeout(drvdata->base, TRCSTATR, TRCSTATR_IDLE_BIT, 1)) { + dev_err(etm_dev, + "timeout while waiting for Idle Trace Status\n"); + etm4_os_unlock(drvdata); + ret = -EBUSY; + goto out; + } + + drvdata->state_needs_restore = true; + + /* + * Power can be removed from the trace unit now. We do this to + * potentially save power on systems that respect the TRCPDCR_PU + * despite requesting software to save/restore state. + */ + writel_relaxed((state->trcpdcr & ~TRCPDCR_PU), + drvdata->base + TRCPDCR); + +out: + CS_LOCK(drvdata->base); + return ret; +} + +static void etm4_cpu_restore(struct etmv4_drvdata *drvdata) +{ + int i; + struct etmv4_save_state *state = drvdata->save_state; + + CS_UNLOCK(drvdata->base); + + writel_relaxed(state->trcclaimset, drvdata->base + TRCCLAIMSET); + + writel_relaxed(state->trcprgctlr, drvdata->base + TRCPRGCTLR); + writel_relaxed(state->trcprocselr, drvdata->base + TRCPROCSELR); + writel_relaxed(state->trcconfigr, drvdata->base + TRCCONFIGR); + writel_relaxed(state->trcauxctlr, drvdata->base + TRCAUXCTLR); + writel_relaxed(state->trceventctl0r, drvdata->base + TRCEVENTCTL0R); + writel_relaxed(state->trceventctl1r, drvdata->base + TRCEVENTCTL1R); + writel_relaxed(state->trcstallctlr, drvdata->base + TRCSTALLCTLR); + writel_relaxed(state->trctsctlr, drvdata->base + TRCTSCTLR); + writel_relaxed(state->trcsyncpr, drvdata->base + TRCSYNCPR); + writel_relaxed(state->trcccctlr, drvdata->base + TRCCCCTLR); + writel_relaxed(state->trcbbctlr, drvdata->base + TRCBBCTLR); + writel_relaxed(state->trctraceidr, drvdata->base + TRCTRACEIDR); + writel_relaxed(state->trcqctlr, drvdata->base + TRCQCTLR); + + writel_relaxed(state->trcvictlr, drvdata->base + TRCVICTLR); + writel_relaxed(state->trcviiectlr, drvdata->base + TRCVIIECTLR); + writel_relaxed(state->trcvissctlr, drvdata->base + TRCVISSCTLR); + writel_relaxed(state->trcvipcssctlr, drvdata->base + TRCVIPCSSCTLR); + writel_relaxed(state->trcvdctlr, drvdata->base + TRCVDCTLR); + writel_relaxed(state->trcvdsacctlr, drvdata->base + TRCVDSACCTLR); + writel_relaxed(state->trcvdarcctlr, drvdata->base + TRCVDARCCTLR); + + for (i = 0; i < drvdata->nrseqstate; i++) + writel_relaxed(state->trcseqevr[i], + drvdata->base + TRCSEQEVRn(i)); + + writel_relaxed(state->trcseqrstevr, drvdata->base + TRCSEQRSTEVR); + writel_relaxed(state->trcseqstr, drvdata->base + TRCSEQSTR); + writel_relaxed(state->trcextinselr, drvdata->base + TRCEXTINSELR); + + for (i = 0; i < drvdata->nr_cntr; i++) { + writel_relaxed(state->trccntrldvr[i], + drvdata->base + TRCCNTRLDVRn(i)); + writel_relaxed(state->trccntctlr[i], + drvdata->base + TRCCNTCTLRn(i)); + writel_relaxed(state->trccntvr[i], + drvdata->base + TRCCNTVRn(i)); + } + + for (i = 0; i < drvdata->nr_resource * 2; i++) + writel_relaxed(state->trcrsctlr[i], + drvdata->base + TRCRSCTLRn(i)); + + for (i = 0; i < drvdata->nr_ss_cmp; i++) { + writel_relaxed(state->trcssccr[i], + drvdata->base + TRCSSCCRn(i)); + writel_relaxed(state->trcsscsr[i], + drvdata->base + TRCSSCSRn(i)); + writel_relaxed(state->trcsspcicr[i], + drvdata->base + TRCSSPCICRn(i)); + } + + for (i = 0; i < drvdata->nr_addr_cmp * 2; i++) { + writel_relaxed(state->trcacvr[i], + drvdata->base + TRCACVRn(i)); + writel_relaxed(state->trcacatr[i], + drvdata->base + TRCACATRn(i)); + } + + for (i = 0; i < drvdata->numcidc; i++) + writel_relaxed(state->trccidcvr[i], + drvdata->base + TRCCIDCVRn(i)); + + for (i = 0; i < drvdata->numvmidc; i++) + writel_relaxed(state->trcvmidcvr[i], + drvdata->base + TRCVMIDCVRn(i)); + + writel_relaxed(state->trccidcctlr0, drvdata->base + TRCCIDCCTLR0); + writel_relaxed(state->trccidcctlr1, drvdata->base + TRCCIDCCTLR1); + + writel_relaxed(state->trcvmidcctlr0, drvdata->base + TRCVMIDCCTLR0); + writel_relaxed(state->trcvmidcctlr0, drvdata->base + TRCVMIDCCTLR1); + + writel_relaxed(state->trcclaimset, drvdata->base + TRCCLAIMSET); + + writel_relaxed(state->trcpdcr, drvdata->base + TRCPDCR); + + drvdata->state_needs_restore = false; + + /* + * As recommended by section 4.3.7 ("Synchronization when using the + * memory-mapped interface") of ARM IHI 0064D + */ + dsb(sy); + isb(); + + /* Unlock the OS lock to re-enable trace and external debug access */ + etm4_os_unlock(drvdata); + CS_LOCK(drvdata->base); +} + +static int etm4_cpu_pm_notify(struct notifier_block *nb, unsigned long cmd, + void *v) +{ + struct etmv4_drvdata *drvdata; + unsigned int cpu = smp_processor_id(); + + if (!etmdrvdata[cpu]) + return NOTIFY_OK; + + drvdata = etmdrvdata[cpu]; + + if (!drvdata->save_state) + return NOTIFY_OK; + + if (WARN_ON_ONCE(drvdata->cpu != cpu)) + return NOTIFY_BAD; + + switch (cmd) { + case CPU_PM_ENTER: + /* save the state if self-hosted coresight is in use */ + if (local_read(&drvdata->mode)) + if (etm4_cpu_save(drvdata)) + return NOTIFY_BAD; + break; + case CPU_PM_EXIT: + /* fallthrough */ + case CPU_PM_ENTER_FAILED: + if (drvdata->state_needs_restore) + etm4_cpu_restore(drvdata); + break; + default: + return NOTIFY_DONE; + } + + return NOTIFY_OK; +} + +static struct notifier_block etm4_cpu_pm_nb = { + .notifier_call = etm4_cpu_pm_notify, +}; + +static int etm4_cpu_pm_register(void) +{ + return cpu_pm_register_notifier(&etm4_cpu_pm_nb); +} + +static void etm4_cpu_pm_unregister(void) +{ + cpu_pm_unregister_notifier(&etm4_cpu_pm_nb); +} +#else +static int etm4_cpu_pm_register(void) { return 0; } +static void etm4_cpu_pm_unregister(void) { } +#endif + static int etm4_probe(struct amba_device *adev, const struct amba_id *id) { int ret; @@ -1101,6 +1402,17 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id) dev_set_drvdata(dev, drvdata); + if (pm_save_enable == PARAM_PM_SAVE_FIRMWARE) + pm_save_enable = coresight_loses_context_with_cpu(dev) ? + PARAM_PM_SAVE_SELF_HOSTED : PARAM_PM_SAVE_NEVER; + + if (pm_save_enable != PARAM_PM_SAVE_NEVER) { + drvdata->save_state = devm_kmalloc(dev, + sizeof(struct etmv4_save_state), GFP_KERNEL); + if (!drvdata->save_state) + return -ENOMEM; + } + /* Validity for the resource is already checked by the AMBA core */ base = devm_ioremap_resource(dev, res); if (IS_ERR(base)) @@ -1135,6 +1447,10 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id) if (ret < 0) goto err_arch_supported; hp_online = ret; + + ret = etm4_cpu_pm_register(); + if (ret) + goto err_arch_supported; } cpus_read_unlock(); @@ -1185,6 +1501,8 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id) err_arch_supported: if (--etm4_count == 0) { + etm4_cpu_pm_unregister(); + cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING); if (hp_online) cpuhp_remove_state_nocalls(hp_online); diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h index 4523f10ddd0f..546d790cb01b 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.h +++ b/drivers/hwtracing/coresight/coresight-etm4x.h @@ -175,6 +175,7 @@ ETM_MODE_EXCL_USER) #define TRCSTATR_IDLE_BIT 0 +#define TRCSTATR_PMSTABLE_BIT 1 #define ETM_DEFAULT_ADDR_COMP 0 /* PowerDown Control Register bits */ @@ -281,6 +282,65 @@ struct etmv4_config { u32 ext_inp; }; +/** + * struct etm4_save_state - state to be preserved when ETM is without power + */ +struct etmv4_save_state { + u32 trcprgctlr; + u32 trcprocselr; + u32 trcconfigr; + u32 trcauxctlr; + u32 trceventctl0r; + u32 trceventctl1r; + u32 trcstallctlr; + u32 trctsctlr; + u32 trcsyncpr; + u32 trcccctlr; + u32 trcbbctlr; + u32 trctraceidr; + u32 trcqctlr; + + u32 trcvictlr; + u32 trcviiectlr; + u32 trcvissctlr; + u32 trcvipcssctlr; + u32 trcvdctlr; + u32 trcvdsacctlr; + u32 trcvdarcctlr; + + u32 trcseqevr[ETM_MAX_SEQ_STATES]; + u32 trcseqrstevr; + u32 trcseqstr; + u32 trcextinselr; + u32 trccntrldvr[ETMv4_MAX_CNTR]; + u32 trccntctlr[ETMv4_MAX_CNTR]; + u32 trccntvr[ETMv4_MAX_CNTR]; + + u32 trcrsctlr[ETM_MAX_RES_SEL * 2]; + + u32 trcssccr[ETM_MAX_SS_CMP]; + u32 trcsscsr[ETM_MAX_SS_CMP]; + u32 trcsspcicr[ETM_MAX_SS_CMP]; + + u64 trcacvr[ETM_MAX_SINGLE_ADDR_CMP]; + u64 trcacatr[ETM_MAX_SINGLE_ADDR_CMP]; + u64 trccidcvr[ETMv4_MAX_CTXID_CMP]; + u32 trcvmidcvr[ETM_MAX_VMID_CMP]; + u32 trccidcctlr0; + u32 trccidcctlr1; + u32 trcvmidcctlr0; + u32 trcvmidcctlr1; + + u32 trcclaimset; + + u32 cntr_val[ETMv4_MAX_CNTR]; + u32 seq_state; + u32 vinst_ctrl; + u32 ss_status[ETM_MAX_SS_CMP]; + + u32 trcpdcr; +}; + /** * struct etm4_drvdata - specifics associated to an ETM component * @base: Memory mapped base address for this component. @@ -336,6 +396,8 @@ struct etmv4_config { * @atbtrig: If the implementation can support ATB triggers * @lpoverride: If the implementation can support low-power state over. * @config: structure holding configuration parameters. + * @save_state: State to be preserved across power loss + * @state_needs_restore: True when there is context to restore after PM exit */ struct etmv4_drvdata { void __iomem *base; @@ -381,6 +443,8 @@ struct etmv4_drvdata { bool atbtrig; bool lpoverride; struct etmv4_config config; + struct etmv4_save_state *save_state; + bool state_needs_restore; }; /* Address comparator access types */ diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c index 6453c67a4d01..e6ca899fea4e 100644 --- a/drivers/hwtracing/coresight/coresight.c +++ b/drivers/hwtracing/coresight/coresight.c @@ -1308,6 +1308,12 @@ static inline int coresight_search_device_idx(struct coresight_dev_list *dict, return -ENOENT; } +bool coresight_loses_context_with_cpu(struct device *dev) +{ + return fwnode_property_present(dev_fwnode(dev), + "arm,coresight-loses-context-with-cpu"); +} + /* * coresight_alloc_device_name - Get an index for a given device in the * device index list specific to a driver. An index is allocated for a diff --git a/include/linux/coresight.h b/include/linux/coresight.h index a2b68823717b..44e552de419c 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -285,6 +285,8 @@ extern void coresight_disclaim_device(void __iomem *base); extern void coresight_disclaim_device_unlocked(void __iomem *base); extern char *coresight_alloc_device_name(struct coresight_dev_list *devs, struct device *dev); + +extern bool coresight_loses_context_with_cpu(struct device *dev); #else static inline struct coresight_device * coresight_register(struct coresight_desc *desc) { return NULL; } @@ -307,6 +309,10 @@ static inline int coresight_claim_device(void __iomem *base) static inline void coresight_disclaim_device(void __iomem *base) {} static inline void coresight_disclaim_device_unlocked(void __iomem *base) {} +static inline bool coresight_loses_context_with_cpu(struct device *dev) +{ + return false; +} #endif extern int coresight_get_cpu(struct device *dev);