On Sun, Dec 09, 2018 at 11:29:42PM +0300, Dmitry Osipenko wrote: > The device-tree binding has been changed. There is no separate GART device > anymore, it is squashed into the Memory Controller. Integrate GART module > with the MC in a way it is done for the SMMU of Tegra30+. > > Signed-off-by: Dmitry Osipenko > --- > drivers/iommu/Kconfig | 1 + > drivers/iommu/tegra-gart.c | 77 ++++++++++++-------------------------- > drivers/memory/tegra/mc.c | 41 ++++++++++++++++++++ > include/soc/tegra/mc.h | 27 +++++++++++++ > 4 files changed, 93 insertions(+), 53 deletions(-) > > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig > index d9a25715650e..83c099bb7288 100644 > --- a/drivers/iommu/Kconfig > +++ b/drivers/iommu/Kconfig > @@ -282,6 +282,7 @@ config ROCKCHIP_IOMMU > config TEGRA_IOMMU_GART > bool "Tegra GART IOMMU Support" > depends on ARCH_TEGRA_2x_SOC > + depends on TEGRA_MC > select IOMMU_API > help > Enables support for remapping discontiguous physical memory > diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c > index 835fea461c59..0a72b6afa842 100644 > --- a/drivers/iommu/tegra-gart.c > +++ b/drivers/iommu/tegra-gart.c > @@ -19,16 +19,17 @@ > * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. > */ > > -#include > #include > #include > #include > #include > -#include > +#include > #include > #include > #include > > +#include > + > /* bitmap of the page sizes currently supported */ > #define GART_IOMMU_PGSIZES (SZ_4K) > > @@ -397,9 +398,8 @@ static const struct iommu_ops gart_iommu_ops = { > .iotlb_sync = gart_iommu_sync, > }; > > -static int tegra_gart_suspend(struct device *dev) > +int tegra_gart_suspend(struct gart_device *gart) > { > - struct gart_device *gart = dev_get_drvdata(dev); > unsigned long iova; > u32 *data = gart->savedata; > unsigned long flags; > @@ -411,9 +411,8 @@ static int tegra_gart_suspend(struct device *dev) > return 0; > } > > -static int tegra_gart_resume(struct device *dev) > +int tegra_gart_resume(struct gart_device *gart) > { > - struct gart_device *gart = dev_get_drvdata(dev); > unsigned long flags; > > spin_lock_irqsave(&gart->pte_lock, flags); > @@ -422,41 +421,39 @@ static int tegra_gart_resume(struct device *dev) > return 0; > } > > -static int tegra_gart_probe(struct platform_device *pdev) > +struct gart_device *tegra_gart_probe(struct device *dev, > + const struct tegra_smmu_soc *soc, > + struct tegra_mc *mc) > { > struct gart_device *gart; > - struct resource *res, *res_remap; > + struct resource *res_remap; > void __iomem *gart_regs; > - struct device *dev = &pdev->dev; > int ret; > > BUILD_BUG_ON(PAGE_SHIFT != GART_PAGE_SHIFT); > > + /* Tegra30+ has an SMMU and no GART */ > + if (soc) > + return NULL; This looks weird. Why do we even call tegra_gart_probe() on anything but Tegra20? > + > /* the GART memory aperture is required */ > - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > - res_remap = platform_get_resource(pdev, IORESOURCE_MEM, 1); > - if (!res || !res_remap) { > + res_remap = platform_get_resource(to_platform_device(dev), > + IORESOURCE_MEM, 1); > + if (!res_remap) { > dev_err(dev, "GART memory aperture expected\n"); > - return -ENXIO; > + return ERR_PTR(-ENXIO); > } > > gart = devm_kzalloc(dev, sizeof(*gart), GFP_KERNEL); > if (!gart) { > dev_err(dev, "failed to allocate gart_device\n"); > - return -ENOMEM; > + return ERR_PTR(-ENOMEM); > } > > - gart_regs = devm_ioremap(dev, res->start, resource_size(res)); > - if (!gart_regs) { > - dev_err(dev, "failed to remap GART registers\n"); > - return -ENXIO; > - } > - > - ret = iommu_device_sysfs_add(&gart->iommu, &pdev->dev, NULL, > - dev_name(&pdev->dev)); > + ret = iommu_device_sysfs_add(&gart->iommu, dev, NULL, "gart"); > if (ret) { > dev_err(dev, "Failed to register IOMMU in sysfs\n"); > - return ret; > + return ERR_PTR(ret); > } > > iommu_device_set_ops(&gart->iommu, &gart_iommu_ops); > @@ -468,7 +465,8 @@ static int tegra_gart_probe(struct platform_device *pdev) > goto remove_sysfs; > } > > - gart->dev = &pdev->dev; > + gart->dev = dev; > + gart_regs = mc->regs + GART_REG_BASE; > spin_lock_init(&gart->pte_lock); > spin_lock_init(&gart->client_lock); > INIT_LIST_HEAD(&gart->client); > @@ -483,46 +481,19 @@ static int tegra_gart_probe(struct platform_device *pdev) > goto unregister_iommu; > } > > - platform_set_drvdata(pdev, gart); > do_gart_setup(gart, NULL); > > gart_handle = gart; > > - return 0; > + return gart; > > unregister_iommu: > iommu_device_unregister(&gart->iommu); > remove_sysfs: > iommu_device_sysfs_remove(&gart->iommu); > > - return ret; > -} > - > -static const struct dev_pm_ops tegra_gart_pm_ops = { > - .suspend = tegra_gart_suspend, > - .resume = tegra_gart_resume, > -}; > - > -static const struct of_device_id tegra_gart_of_match[] = { > - { .compatible = "nvidia,tegra20-gart", }, > - { }, > -}; > - > -static struct platform_driver tegra_gart_driver = { > - .probe = tegra_gart_probe, > - .driver = { > - .name = "tegra-gart", > - .pm = &tegra_gart_pm_ops, > - .of_match_table = tegra_gart_of_match, > - .suppress_bind_attrs = true, > - }, > -}; > - > -static int __init tegra_gart_init(void) > -{ > - return platform_driver_register(&tegra_gart_driver); > + return ERR_PTR(ret); > } > -subsys_initcall(tegra_gart_init); > > module_param(gart_debug, bool, 0644); > MODULE_PARM_DESC(gart_debug, "Enable GART debugging"); > diff --git a/drivers/memory/tegra/mc.c b/drivers/memory/tegra/mc.c > index 55ecfb2d8cfd..4cae1c3a853b 100644 > --- a/drivers/memory/tegra/mc.c > +++ b/drivers/memory/tegra/mc.c > @@ -702,13 +702,54 @@ static int tegra_mc_probe(struct platform_device *pdev) > PTR_ERR(mc->smmu)); > } > > + if (IS_ENABLED(CONFIG_TEGRA_IOMMU_GART)) { > + mc->gart = tegra_gart_probe(&pdev->dev, mc->soc->smmu, mc); > + if (IS_ERR(mc->gart)) > + dev_err(&pdev->dev, "failed to probe GART: %ld\n", > + PTR_ERR(mc->gart)); > + } Perhaps if we add a check for for !mc->soc->smmu here we can avoid passing this data structure to tegra_gart_probe() and remove the corresponding check from tegra_gart_probe(). That seems more like a more logical sequence than attempting to probe GART on device that may not have one and return. Also, since there's no error return here, do we want to set mc->gart to NULL on error to avoid crashing later on... > + > + return 0; > +} > + > +static int tegra_mc_suspend(struct device *dev) > +{ > + struct tegra_mc *mc = dev_get_drvdata(dev); > + int err; > + > + if (mc->gart) { ... like here? > + err = tegra_gart_suspend(mc->gart); > + if (err) > + return err; > + } > + > return 0; > } > > +static int tegra_mc_resume(struct device *dev) > +{ > + struct tegra_mc *mc = dev_get_drvdata(dev); > + int err; > + > + if (mc->gart) { And here? > + err = tegra_gart_resume(mc->gart); > + if (err) > + return err; > + } > + > + return 0; > +} > + > +static const struct dev_pm_ops tegra_mc_pm_ops = { > + .suspend = tegra_mc_suspend, > + .resume = tegra_mc_resume, > +}; > + > static struct platform_driver tegra_mc_driver = { > .driver = { > .name = "tegra-mc", > .of_match_table = tegra_mc_of_match, > + .pm = &tegra_mc_pm_ops, > .suppress_bind_attrs = true, > }, > .prevent_deferred_probe = true, > diff --git a/include/soc/tegra/mc.h b/include/soc/tegra/mc.h > index db5bfdf589b4..5da42e3fb801 100644 > --- a/include/soc/tegra/mc.h > +++ b/include/soc/tegra/mc.h > @@ -77,6 +77,7 @@ struct tegra_smmu_soc { > > struct tegra_mc; > struct tegra_smmu; > +struct gart_device; > > #ifdef CONFIG_TEGRA_IOMMU_SMMU > struct tegra_smmu *tegra_smmu_probe(struct device *dev, > @@ -96,6 +97,31 @@ static inline void tegra_smmu_remove(struct tegra_smmu *smmu) > } > #endif > > +#ifdef CONFIG_TEGRA_IOMMU_GART > +struct gart_device *tegra_gart_probe(struct device *dev, > + const struct tegra_smmu_soc *soc, > + struct tegra_mc *mc); > +int tegra_gart_suspend(struct gart_device *gart); > +int tegra_gart_resume(struct gart_device *gart); > +#else > +static inline struct gart_device * > +tegra_gart_probe(struct device *dev, const struct tegra_smmu_soc *soc, > + struct tegra_mc *mc) > +{ > + return NULL; > +} > + > +static inline int tegra_gart_suspend(struct gart_device *gart) > +{ > + return -ENODEV; > +} > + > +static inline int tegra_gart_resume(struct gart_device *gart) > +{ > + return -ENODEV; > +} > +#endif That doesn't look right. If we don't enable GART, then the dummy implementations will be used, but they return error codes, so suspend/resume of MC will also fail, causing the whole system to not be able to suspend if GART is disabled. I think it'd be better to avoid the dummy functions and instead add extra checks for IS_ENABLED(CONFIG_TEGRA_IOMMU_GART) where these are called. That way references to these functions should be discarded at translation time. To be specific, tegra_mc_suspend() and tegra_mc_resume() would change like this: if (IS_ENABLED(CONFIG_TEGRA_IOMMU_GART) && mc->gart) Thierry