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From: Mike Leach <Mike.Leach@arm.com>
To: Andrew Murray <Andrew.Murray@arm.com>,
	Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	"coresight@lists.linaro.org" <coresight@lists.linaro.org>,
	Mike Leach <mike.leach@linaro.org>,
	"linux-arm-kernel@lists.infradead.org"
	<linux-arm-kernel@lists.infradead.org>,
	Sudeep Holla <Sudeep.Holla@arm.com>
Subject: RE: [PATCH v4 5/6] coresight: etm4x: save/restore state across CPU low power states
Date: Wed, 31 Jul 2019 08:16:08 +0000
Message-ID: <VE1PR08MB4638FFA34F7AFDDE907F43388CDF0@VE1PR08MB4638.eurprd08.prod.outlook.com> (raw)
In-Reply-To: <20190730214542.GH56241@e119886-lin.cambridge.arm.com>

Hi,

Since the decision has apparently been made to ignore the needs of external debug agents, then the "state" struct & variable used in this and the previously mentioned issues around allocating it are un-necessary complication. Simply use the existing config in the driver that contains all of the values that you need - and save on additional memory usage by the drivers.

Regards

Mike


> -----Original Message-----
> From: CoreSight <coresight-bounces@lists.linaro.org> On Behalf Of Andrew
> Murray
> Sent: 30 July 2019 22:46
> To: Mathieu Poirier <mathieu.poirier@linaro.org>
> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>;
> coresight@lists.linaro.org; Sudeep Holla <Sudeep.Holla@arm.com>; linux-
> arm-kernel@lists.infradead.org; Mike Leach <mike.leach@linaro.org>
> Subject: Re: [PATCH v4 5/6] coresight: etm4x: save/restore state across CPU
> low power states
>
> On Tue, Jul 30, 2019 at 03:16:33PM -0600, Mathieu Poirier wrote:
> > On Tue, Jul 30, 2019 at 01:51:56PM +0100, Andrew Murray wrote:
> > > Some hardware will ignore bit TRCPDCR.PU which is used to signal to
> > > hardware that power should not be removed from the trace unit.
> > > Let's mitigate against this by conditionally saving and restoring
> > > the trace unit state when the CPU enters low power states.
> > >
> > > This patchset introduces a firmware property named
> > > 'arm,coresight-needs-save-restore' - when this is present the
> > > hardware state will be conditionally saved and restored.
> > >
> > > A module parameter 'pm_save_enable' is also introduced which can be
> > > configured to override the firmware property. This can be set to
> > > never allow save/restore, to conditionally allow it, or to do as the
> > > firmware indicates (default).
> > >
> > > We avoid saving the hardware state when coresight isn't in use to
> > > reduce PM latency - we can't determine this by reading the claim
> > > tags (TRCCLAIMCLR) as these are 'trace' registers which need power
> > > and clocking, something we can't easily provide in the PM context.
> > > Therefore we rely on the existing drvdata->mode internal state that
> > > is set when self-hosted coresight is used (and powered).
> > >
> > > As we do not have a simple way of determining if an external agent
> > > is using coresight, we don't save/restore for this use case.
> > >
> > > Signed-off-by: Andrew Murray <andrew.murray@arm.com>
> > > ---
> > >  drivers/hwtracing/coresight/coresight-etm4x.c | 322
> > > ++++++++++++++++++  drivers/hwtracing/coresight/coresight-etm4x.h |
> > > 64 ++++
> > >  2 files changed, 386 insertions(+)
> > >
> > > diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c
> > > b/drivers/hwtracing/coresight/coresight-etm4x.c
> > > index a128b5063f46..30f118792289 100644
> > > --- a/drivers/hwtracing/coresight/coresight-etm4x.c
> > > +++ b/drivers/hwtracing/coresight/coresight-etm4x.c
> > > @@ -18,6 +18,7 @@
> > >  #include <linux/stat.h>
> > >  #include <linux/clk.h>
> > >  #include <linux/cpu.h>
> > > +#include <linux/cpu_pm.h>
> > >  #include <linux/coresight.h>
> > >  #include <linux/coresight-pmu.h>
> > >  #include <linux/pm_wakeup.h>
> > > @@ -26,6 +27,7 @@
> > >  #include <linux/uaccess.h>
> > >  #include <linux/perf_event.h>
> > >  #include <linux/pm_runtime.h>
> > > +#include <linux/property.h>
> > >  #include <asm/sections.h>
> > >  #include <asm/local.h>
> > >  #include <asm/virt.h>
> > > @@ -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_NEVER0 /* never save/restore state
> */
> > > +#define PARAM_PM_SAVE_ALWAYS1 /* always save/restore
> state */
> > > +#define PARAM_PM_SAVE_FIRMWARE2 /* only save/restore if
> firmware flag set */
> > > +
> > > +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: 0 = never, 1 = always, 2 =
> > > +firmware");
> > > +
> > >  /* 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 +1104,294
> @@
> > > 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 0;
> > > +
> > > +drvdata = etmdrvdata[cpu];
> > > +
> > > +if (!drvdata->save_state)
> > > +return NOTIFY_OK;
> >
> > The problem here is that if no memory was allocated for ->save_state
> > at boot time and someone does:
> >         $ echo 1 >
> > /sys/module/coresight_etm4x/parameters/pm_save_enable
> >
> > then they will be mislead in thinking that save/restore operations are
> > taking place.  To avoid the problem I suggest to use module_param_cb()
> > where memory can be allocated and freed as the functionality is requested
> by users.
>
> Actually notice the permissions of pm_save_enable:
>
> > > +module_param(pm_save_enable, int, 0444);
>
> I changed this to be readonly after boot. I initially started down the track of
> module_param_cb, but allocating memory ahead of when it is needed was
> slightly complex as the module_param_cb callback doesn't have drvdata and
> so you'd have to figure out which of the etmdrvdata's to allocate for
> (perhaps all those that are not NULL). You'd also have to allocate on probe as
> well.
>
> Besides the benefit of changing the param via sysfs for testing, I'm not sure
> that this is all that useful to anyone - especially as we currently don't support
> save/restore for external debug. Unless there are potential coresight users
> that don't have the ability to change the kernel command line or device tree?
>
> Thanks,
>
> Andrew Murray
>
> >
> > Thanks,
> > Mathieu
> >
> > > +
> > > +if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id()))
> > > +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:
> > > +case CPU_PM_ENTER_FAILED:
> > > +/* trcclaimset is set when there is state to restore */
> > > +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 inline bool etm4_needs_save_restore(struct device *dev) {
> > > +return fwnode_property_present(dev->fwnode,
> > > +       "arm,coresight-needs-save-restore");
> > > +}
> > > +
> > >  static int etm4_probe(struct amba_device *adev, const struct
> > > amba_id *id)  {
> > >  int ret;
> > > @@ -1101,6 +1408,15 @@ 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_ALWAYS ||
> > > +    (pm_save_enable == PARAM_PM_SAVE_FIRMWARE &&
> > > +     etm4_needs_save_restore(dev))) {
> > > +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 +1451,10 @@ 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 +1505,8 @@ 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_STARTI
> NG);
> > >  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_BIT0
> > > +#define TRCSTATR_PMSTABLE_BIT1
> > >  #define ETM_DEFAULT_ADDR_COMP0
> > >
> > >  /* PowerDown Control Register bits */ @@ -281,6 +282,65 @@ struct
> > > etmv4_config {
> > >  u32ext_inp;
> > >  };
> > >
> > > +/**
> > > + * struct etm4_save_state - state to be preserved when ETM is
> > > +without power  */ struct etmv4_save_state {
> > > +u32trcprgctlr;
> > > +u32trcprocselr;
> > > +u32trcconfigr;
> > > +u32trcauxctlr;
> > > +u32trceventctl0r;
> > > +u32trceventctl1r;
> > > +u32trcstallctlr;
> > > +u32trctsctlr;
> > > +u32trcsyncpr;
> > > +u32trcccctlr;
> > > +u32trcbbctlr;
> > > +u32trctraceidr;
> > > +u32trcqctlr;
> > > +
> > > +u32trcvictlr;
> > > +u32trcviiectlr;
> > > +u32trcvissctlr;
> > > +u32trcvipcssctlr;
> > > +u32trcvdctlr;
> > > +u32trcvdsacctlr;
> > > +u32trcvdarcctlr;
> > > +
> > > +u32trcseqevr[ETM_MAX_SEQ_STATES];
> > > +u32trcseqrstevr;
> > > +u32trcseqstr;
> > > +u32trcextinselr;
> > > +u32trccntrldvr[ETMv4_MAX_CNTR];
> > > +u32trccntctlr[ETMv4_MAX_CNTR];
> > > +u32trccntvr[ETMv4_MAX_CNTR];
> > > +
> > > +u32trcrsctlr[ETM_MAX_RES_SEL * 2];
> > > +
> > > +u32trcssccr[ETM_MAX_SS_CMP];
> > > +u32trcsscsr[ETM_MAX_SS_CMP];
> > > +u32trcsspcicr[ETM_MAX_SS_CMP];
> > > +
> > > +u64trcacvr[ETM_MAX_SINGLE_ADDR_CMP];
> > > +u64trcacatr[ETM_MAX_SINGLE_ADDR_CMP];
> > > +u64trccidcvr[ETMv4_MAX_CTXID_CMP];
> > > +u32trcvmidcvr[ETM_MAX_VMID_CMP];
> > > +u32trccidcctlr0;
> > > +u32trccidcctlr1;
> > > +u32trcvmidcctlr0;
> > > +u32trcvmidcctlr1;
> > > +
> > > +u32trcclaimset;
> > > +
> > > +u32cntr_val[ETMv4_MAX_CNTR];
> > > +u32seq_state;
> > > +u32vinst_ctrl;
> > > +u32ss_status[ETM_MAX_SS_CMP];
> > > +
> > > +u32trcpdcr;
> > > +};
> > > +
> > >  /**
> > >   * 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 {
> > >  boolatbtrig;
> > >  boollpoverride;
> > >  struct etmv4_configconfig;
> > > +struct etmv4_save_state*save_state;
> > > +boolstate_needs_restore;
> > >  };
> > >
> > >  /* Address comparator access types */
> > > --
> > > 2.21.0
> > >
> _______________________________________________
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  reply index

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-30 12:51 [PATCH v4 0/6] coresight: etm4x: save/restore ETMv4 context " Andrew Murray
2019-07-30 12:51 ` [PATCH v4 1/6] coresight: etm4x: remove superfluous setting of os_unlock Andrew Murray
2019-07-30 12:51 ` [PATCH v4 2/6] coresight: etm4x: use explicit barriers on enable/disable Andrew Murray
2019-08-01 13:31   ` Sasha Levin
2019-08-01 14:48     ` Mathieu Poirier
2019-08-02 18:08   ` Sasha Levin
2019-07-30 12:51 ` [PATCH v4 3/6] coresight: etm4x: use module_param instead of module_param_named Andrew Murray
2019-08-02 10:23   ` Suzuki K Poulose
2019-07-30 12:51 ` [PATCH v4 4/6] coresight: etm4x: improve clarity of etm4_os_unlock comment Andrew Murray
2019-07-30 12:51 ` [PATCH v4 5/6] coresight: etm4x: save/restore state across CPU low power states Andrew Murray
2019-07-30 21:16   ` Mathieu Poirier
2019-07-30 21:45     ` Andrew Murray
2019-07-31  8:16       ` Mike Leach [this message]
2019-07-31  9:45         ` Andrew Murray
2019-08-02 10:54   ` Suzuki K Poulose
2019-08-14  9:12     ` Andrew Murray
2019-07-30 12:51 ` [PATCH v4 6/6] dt-bindings: arm: coresight: Add support for coresight-needs-save-restore Andrew Murray
2019-08-02 10:40   ` Suzuki K Poulose
2019-08-02 14:37     ` Andrew Murray
2019-08-04 13:13       ` Mathieu Poirier
2019-08-14 10:01         ` Andrew Murray
2019-08-14 11:06           ` Mike Leach
2019-08-14 12:35             ` Suzuki K Poulose
2019-08-14 12:49               ` Andrew Murray
2019-08-14 14:20               ` Mike Leach
2019-07-30 20:12 ` [PATCH v4 0/6] coresight: etm4x: save/restore ETMv4 context across CPU low power states Mathieu Poirier
2019-07-30 21:46   ` Andrew Murray

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