| Message ID | 20180827105551.16346-3-vivek.gautam@codeaurora.org (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | iommu/arm-smmu: Add runtime pm/sleep support | expand |
On Mon, Aug 27, 2018 at 4:27 PM Vivek Gautam <vivek.gautam@codeaurora.org> wrote: > > From: Sricharan R <sricharan@codeaurora.org> > > The smmu device probe/remove and add/remove master device callbacks > gets called when the smmu is not linked to its master, that is without > the context of the master device. So calling runtime apis in those places > separately. > > Signed-off-by: Sricharan R <sricharan@codeaurora.org> > [vivek: Cleanup pm runtime calls] > Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> > Reviewed-by: Tomasz Figa <tfiga@chromium.org> > Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> > --- > > Changes since v14: > - none. > > drivers/iommu/arm-smmu.c | 101 +++++++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 93 insertions(+), 8 deletions(-) > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > index a81224bc6637..23b4a60149b6 100644 > --- a/drivers/iommu/arm-smmu.c > +++ b/drivers/iommu/arm-smmu.c [snip] > @@ -2131,6 +2188,26 @@ static int arm_smmu_device_probe(struct platform_device *pdev) > if (err) > return err; > > + /* > + * We want to avoid touching dev->power.lock in fastpaths unless > + * it's really going to do something useful - pm_runtime_enabled() > + * can serve as an ideal proxy for that decision. So, conditionally > + * enable pm_runtime. > + */ > + if (dev->pm_domain) > + pm_runtime_enable(dev); > + > + err = arm_smmu_rpm_get(smmu); We shouldn't be doing a runtime_get() yet, as this eventually calls arm_smmu_device_reset(). arm_smmu_device_reset() should be called only after arm_smmu_device_cfg_probe(). So, I plan to replace the pm_runtime_get/put() calls in probe() with simple clk_bulk_enable() to let the driver initialize smmu, and at the end of the probe we can disable the clocks and enable runtime pm over the device to let it take care of the device further-on. > + if (err < 0) > + return err; > + > + /* Enable clocks explicitly if runtime PM is disabled */ > + if (!pm_runtime_enabled(dev)) { > + err = clk_bulk_enable(smmu->num_clks, smmu->clks); > + if (err) > + return err; > + } > + > err = arm_smmu_device_cfg_probe(smmu); > if (err) > return err; [snip] Best regards Vivek -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
On Thu, Aug 30, 2018 at 6:22 PM Vivek Gautam <vivek.gautam@codeaurora.org> wrote: > > On Mon, Aug 27, 2018 at 4:27 PM Vivek Gautam > <vivek.gautam@codeaurora.org> wrote: > > > > From: Sricharan R <sricharan@codeaurora.org> > > > > The smmu device probe/remove and add/remove master device callbacks > > gets called when the smmu is not linked to its master, that is without > > the context of the master device. So calling runtime apis in those places > > separately. > > > > Signed-off-by: Sricharan R <sricharan@codeaurora.org> > > [vivek: Cleanup pm runtime calls] > > Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> > > Reviewed-by: Tomasz Figa <tfiga@chromium.org> > > Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> > > --- > > > > Changes since v14: > > - none. > > > > drivers/iommu/arm-smmu.c | 101 +++++++++++++++++++++++++++++++++++++++++++---- > > 1 file changed, 93 insertions(+), 8 deletions(-) > > > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > > index a81224bc6637..23b4a60149b6 100644 > > --- a/drivers/iommu/arm-smmu.c > > +++ b/drivers/iommu/arm-smmu.c > > [snip] > > > @@ -2131,6 +2188,26 @@ static int arm_smmu_device_probe(struct platform_device *pdev) > > if (err) > > return err; > > > > + /* > > + * We want to avoid touching dev->power.lock in fastpaths unless > > + * it's really going to do something useful - pm_runtime_enabled() > > + * can serve as an ideal proxy for that decision. So, conditionally > > + * enable pm_runtime. > > + */ > > + if (dev->pm_domain) > > + pm_runtime_enable(dev); > > + > > + err = arm_smmu_rpm_get(smmu); > > We shouldn't be doing a runtime_get() yet, as this eventually calls > arm_smmu_device_reset(). > arm_smmu_device_reset() should be called only after arm_smmu_device_cfg_probe(). > So, I plan to replace the pm_runtime_get/put() calls in probe() with > simple clk_bulk_enable() > to let the driver initialize smmu, and at the end of the probe we can > disable the clocks and > enable runtime pm over the device to let it take care of the device further-on. > We can avoid the explicit clock disable by just calling pm_runtime_set_active() before pm_runtime_enable(), assuming that what probe does is symmetrical with the suspend callback, which would be called after the latter. Best regards, Tomasz
On Thu, Aug 30, 2018 at 3:04 PM Tomasz Figa <tfiga@chromium.org> wrote: > > On Thu, Aug 30, 2018 at 6:22 PM Vivek Gautam > <vivek.gautam@codeaurora.org> wrote: > > > > On Mon, Aug 27, 2018 at 4:27 PM Vivek Gautam > > <vivek.gautam@codeaurora.org> wrote: > > > > > > From: Sricharan R <sricharan@codeaurora.org> > > > > > > The smmu device probe/remove and add/remove master device callbacks > > > gets called when the smmu is not linked to its master, that is without > > > the context of the master device. So calling runtime apis in those places > > > separately. > > > > > > Signed-off-by: Sricharan R <sricharan@codeaurora.org> > > > [vivek: Cleanup pm runtime calls] > > > Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> > > > Reviewed-by: Tomasz Figa <tfiga@chromium.org> > > > Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> > > > --- > > > > > > Changes since v14: > > > - none. > > > > > > drivers/iommu/arm-smmu.c | 101 +++++++++++++++++++++++++++++++++++++++++++---- > > > 1 file changed, 93 insertions(+), 8 deletions(-) > > > > > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > > > index a81224bc6637..23b4a60149b6 100644 > > > --- a/drivers/iommu/arm-smmu.c > > > +++ b/drivers/iommu/arm-smmu.c > > > > [snip] > > > > > @@ -2131,6 +2188,26 @@ static int arm_smmu_device_probe(struct platform_device *pdev) > > > if (err) > > > return err; > > > > > > + /* > > > + * We want to avoid touching dev->power.lock in fastpaths unless > > > + * it's really going to do something useful - pm_runtime_enabled() > > > + * can serve as an ideal proxy for that decision. So, conditionally > > > + * enable pm_runtime. > > > + */ > > > + if (dev->pm_domain) > > > + pm_runtime_enable(dev); > > > + > > > + err = arm_smmu_rpm_get(smmu); > > > > We shouldn't be doing a runtime_get() yet, as this eventually calls > > arm_smmu_device_reset(). > > arm_smmu_device_reset() should be called only after arm_smmu_device_cfg_probe(). > > So, I plan to replace the pm_runtime_get/put() calls in probe() with > > simple clk_bulk_enable() > > to let the driver initialize smmu, and at the end of the probe we can > > disable the clocks and > > enable runtime pm over the device to let it take care of the device further-on. > > > > We can avoid the explicit clock disable by just calling > pm_runtime_set_active() before pm_runtime_enable(), assuming that what > probe does is symmetrical with the suspend callback, which would be > called after the latter. Sure, that sounds reasonable. Will use pm_runtime_set_active() instead of explicitly disabling the clocks.Thanks. Best regards Vivek > > Best regards, > Tomasz > _______________________________________________ > iommu mailing list > iommu@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/iommu
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index a81224bc6637..23b4a60149b6 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -268,6 +268,20 @@ static struct arm_smmu_option_prop arm_smmu_options[] = { { 0, NULL}, }; +static inline int arm_smmu_rpm_get(struct arm_smmu_device *smmu) +{ + if (pm_runtime_enabled(smmu->dev)) + return pm_runtime_get_sync(smmu->dev); + + return 0; +} + +static inline void arm_smmu_rpm_put(struct arm_smmu_device *smmu) +{ + if (pm_runtime_enabled(smmu->dev)) + pm_runtime_put(smmu->dev); +} + static struct arm_smmu_domain *to_smmu_domain(struct iommu_domain *dom) { return container_of(dom, struct arm_smmu_domain, domain); @@ -913,11 +927,15 @@ static void arm_smmu_destroy_domain_context(struct iommu_domain *domain) struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); struct arm_smmu_device *smmu = smmu_domain->smmu; struct arm_smmu_cfg *cfg = &smmu_domain->cfg; - int irq; + int ret, irq; if (!smmu || domain->type == IOMMU_DOMAIN_IDENTITY) return; + ret = arm_smmu_rpm_get(smmu); + if (ret < 0) + return; + /* * Disable the context bank and free the page tables before freeing * it. @@ -932,6 +950,8 @@ static void arm_smmu_destroy_domain_context(struct iommu_domain *domain) free_io_pgtable_ops(smmu_domain->pgtbl_ops); __arm_smmu_free_bitmap(smmu->context_map, cfg->cbndx); + + arm_smmu_rpm_put(smmu); } static struct iommu_domain *arm_smmu_domain_alloc(unsigned type) @@ -1213,10 +1233,15 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) return -ENODEV; smmu = fwspec_smmu(fwspec); + + ret = arm_smmu_rpm_get(smmu); + if (ret < 0) + return ret; + /* Ensure that the domain is finalised */ ret = arm_smmu_init_domain_context(domain, smmu); if (ret < 0) - return ret; + goto rpm_put; /* * Sanity check the domain. We don't support domains across @@ -1226,33 +1251,50 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) dev_err(dev, "cannot attach to SMMU %s whilst already attached to domain on SMMU %s\n", dev_name(smmu_domain->smmu->dev), dev_name(smmu->dev)); - return -EINVAL; + ret = -EINVAL; + goto rpm_put; } /* Looks ok, so add the device to the domain */ - return arm_smmu_domain_add_master(smmu_domain, fwspec); + ret = arm_smmu_domain_add_master(smmu_domain, fwspec); + +rpm_put: + arm_smmu_rpm_put(smmu); + return ret; } static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova, phys_addr_t paddr, size_t size, int prot) { struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops; + struct arm_smmu_device *smmu = to_smmu_domain(domain)->smmu; + int ret; if (!ops) return -ENODEV; - return ops->map(ops, iova, paddr, size, prot); + arm_smmu_rpm_get(smmu); + ret = ops->map(ops, iova, paddr, size, prot); + arm_smmu_rpm_put(smmu); + + return ret; } static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size) { struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops; + struct arm_smmu_device *smmu = to_smmu_domain(domain)->smmu; + size_t ret; if (!ops) return 0; - return ops->unmap(ops, iova, size); + arm_smmu_rpm_get(smmu); + ret = ops->unmap(ops, iova, size); + arm_smmu_rpm_put(smmu); + + return ret; } static void arm_smmu_iotlb_sync(struct iommu_domain *domain) @@ -1407,7 +1449,13 @@ static int arm_smmu_add_device(struct device *dev) while (i--) cfg->smendx[i] = INVALID_SMENDX; + ret = arm_smmu_rpm_get(smmu); + if (ret < 0) + goto out_cfg_free; + ret = arm_smmu_master_alloc_smes(dev); + arm_smmu_rpm_put(smmu); + if (ret) goto out_cfg_free; @@ -1427,7 +1475,7 @@ static void arm_smmu_remove_device(struct device *dev) struct iommu_fwspec *fwspec = dev->iommu_fwspec; struct arm_smmu_master_cfg *cfg; struct arm_smmu_device *smmu; - + int ret; if (!fwspec || fwspec->ops != &arm_smmu_ops) return; @@ -1435,8 +1483,15 @@ static void arm_smmu_remove_device(struct device *dev) cfg = fwspec->iommu_priv; smmu = cfg->smmu; + ret = arm_smmu_rpm_get(smmu); + if (ret < 0) + return; + iommu_device_unlink(&smmu->iommu, dev); arm_smmu_master_free_smes(fwspec); + + arm_smmu_rpm_put(smmu); + iommu_group_remove_device(dev); kfree(fwspec->iommu_priv); iommu_fwspec_free(dev); @@ -2123,6 +2178,8 @@ static int arm_smmu_device_probe(struct platform_device *pdev) smmu->irqs[i] = irq; } + platform_set_drvdata(pdev, smmu); + err = devm_clk_bulk_get(smmu->dev, smmu->num_clks, smmu->clks); if (err) return err; @@ -2131,6 +2188,26 @@ static int arm_smmu_device_probe(struct platform_device *pdev) if (err) return err; + /* + * We want to avoid touching dev->power.lock in fastpaths unless + * it's really going to do something useful - pm_runtime_enabled() + * can serve as an ideal proxy for that decision. So, conditionally + * enable pm_runtime. + */ + if (dev->pm_domain) + pm_runtime_enable(dev); + + err = arm_smmu_rpm_get(smmu); + if (err < 0) + return err; + + /* Enable clocks explicitly if runtime PM is disabled */ + if (!pm_runtime_enabled(dev)) { + err = clk_bulk_enable(smmu->num_clks, smmu->clks); + if (err) + return err; + } + err = arm_smmu_device_cfg_probe(smmu); if (err) return err; @@ -2176,10 +2253,11 @@ static int arm_smmu_device_probe(struct platform_device *pdev) return err; } - platform_set_drvdata(pdev, smmu); arm_smmu_device_reset(smmu); arm_smmu_test_smr_masks(smmu); + arm_smmu_rpm_put(smmu); + /* * For ACPI and generic DT bindings, an SMMU will be probed before * any device which might need it, so we want the bus ops in place @@ -2215,8 +2293,15 @@ static int arm_smmu_device_remove(struct platform_device *pdev) if (!bitmap_empty(smmu->context_map, ARM_SMMU_MAX_CBS)) dev_err(&pdev->dev, "removing device with active domains!\n"); + arm_smmu_rpm_get(smmu); /* Turn the thing off */ writel(sCR0_CLIENTPD, ARM_SMMU_GR0_NS(smmu) + ARM_SMMU_GR0_sCR0); + arm_smmu_rpm_put(smmu); + + if (pm_runtime_enabled(smmu->dev)) + pm_runtime_force_suspend(smmu->dev); + else + clk_bulk_disable(smmu->num_clks, smmu->clks); clk_bulk_unprepare(smmu->num_clks, smmu->clks);