On Thu, 12 May 2016 16:19:32 +0100 Jon Hunter <jonathanh@xxxxxxxxxx> wrote: > Add a platform driver to support non-root GICs that require runtime > power-management. Currently, only non-root GICs are supported because > the functions, smp_cross_call() and set_handle_irq(), that need to > be called for a root controller are located in the __init section and > so cannot be called by the platform driver. > > The GIC platform driver re-uses many functions from the existing GIC > driver including some functions to save and restore the GIC context > during power transitions. The functions for saving and restoring the > GIC context are currently only defined if CONFIG_CPU_PM is enabled and > to ensure that these functions are always defined when the platform > driver is enabled, a dependency on CONFIG_ARM_GIC_PM (which selects the > platform driver) has been added. > > In order to re-use the private GIC initialisation code, a new public > function, of_gic_init(), has been added which calls various private > functions to initialise the GIC. > > There is no specific suspend handling for GICs registered as platform > devices. Non-wakeup interrupts will be disabled by the kernel during > late suspend, however, this alone will not power down the GIC if > interrupts have been requested and not freed. Therefore, requestors of > non-wakeup interrupts will need to free them on entering suspend in > order to power-down the GIC. > > Signed-off-by: Jon Hunter <jonathanh@xxxxxxxxxx> > --- > drivers/irqchip/Kconfig | 6 ++ > drivers/irqchip/Makefile | 1 + > drivers/irqchip/irq-gic-pm.c | 187 +++++++++++++++++++++++++++++++++++++++++++ > drivers/irqchip/irq-gic.c | 34 +++++++- > drivers/irqchip/irq-gic.h | 2 + > 5 files changed, 227 insertions(+), 3 deletions(-) > create mode 100644 drivers/irqchip/irq-gic-pm.c > > diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig > index 81f88ada3a61..68f65c84fdfd 100644 > --- a/drivers/irqchip/Kconfig > +++ b/drivers/irqchip/Kconfig > @@ -8,6 +8,12 @@ config ARM_GIC > select IRQ_DOMAIN_HIERARCHY > select MULTI_IRQ_HANDLER > > +config ARM_GIC_PM > + bool > + depends on PM > + select ARM_GIC > + select PM_CLK > + > config ARM_GIC_MAX_NR > int > default 2 if ARCH_REALVIEW > diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile > index f828244b44c2..eab28e80cd8d 100644 > --- a/drivers/irqchip/Makefile > +++ b/drivers/irqchip/Makefile > @@ -24,6 +24,7 @@ obj-$(CONFIG_ARCH_SUNXI) += irq-sun4i.o > obj-$(CONFIG_ARCH_SUNXI) += irq-sunxi-nmi.o > obj-$(CONFIG_ARCH_SPEAR3XX) += spear-shirq.o > obj-$(CONFIG_ARM_GIC) += irq-gic.o irq-gic-common.o > +obj-$(CONFIG_ARM_GIC_PM) += irq-gic-pm.o > obj-$(CONFIG_REALVIEW_DT) += irq-gic-realview.o > obj-$(CONFIG_ARM_GIC_V2M) += irq-gic-v2m.o > obj-$(CONFIG_ARM_GIC_V3) += irq-gic-v3.o irq-gic-common.o > diff --git a/drivers/irqchip/irq-gic-pm.c b/drivers/irqchip/irq-gic-pm.c > new file mode 100644 > index 000000000000..a14331007bcf > --- /dev/null > +++ b/drivers/irqchip/irq-gic-pm.c > @@ -0,0 +1,187 @@ > +/* > + * Copyright (C) 2016 NVIDIA CORPORATION, All Rights Reserved. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program. If not, see <http://www.gnu.org/licenses/>. > + */ > +#include <linux/module.h> > +#include <linux/clk.h> > +#include <linux/of_device.h> > +#include <linux/of_irq.h> > +#include <linux/platform_device.h> > +#include <linux/pm_clock.h> > +#include <linux/pm_runtime.h> > +#include <linux/slab.h> > + > +#include "irq-gic.h" > + > +struct gic_clk_data { > + unsigned int num_clocks; > + const char *const *clocks; > +}; > + > +static int gic_runtime_resume(struct device *dev) > +{ > + struct gic_chip_data *gic = dev_get_drvdata(dev); > + int ret; > + > + ret = pm_clk_resume(dev); > + if (ret) > + return ret; > + > + /* > + * On the very first resume, the pointer to the driver data > + * will be NULL and this is intentional, because we do not > + * want to restore the GIC on the very first resume. So if > + * the pointer is not valid just return. > + */ > + if (!gic) > + return 0; > + > + gic_dist_restore(gic); > + gic_cpu_restore(gic); > + > + return 0; > +} > + > +static int gic_runtime_suspend(struct device *dev) > +{ > + struct gic_chip_data *gic = dev_get_drvdata(dev); > + > + gic_dist_save(gic); > + gic_cpu_save(gic); > + > + return pm_clk_suspend(dev); > +} > + > +static int gic_get_clocks(struct device *dev, const struct gic_clk_data *data) > +{ > + struct clk *clk; > + unsigned int i; > + int ret; > + > + if (!dev || !data) > + return -EINVAL; > + > + ret = pm_clk_create(dev); > + if (ret) > + return ret; > + > + for (i = 0; i < data->num_clocks; i++) { > + clk = of_clk_get_by_name(dev->of_node, data->clocks[i]); > + if (IS_ERR(clk)) { > + dev_err(dev, "failed to get clock %s\n", > + data->clocks[i]); > + ret = PTR_ERR(clk); > + goto error; > + } > + > + ret = pm_clk_add_clk(dev, clk); > + if (ret) { > + dev_err(dev, "failed to add clock at index %d\n", i); > + clk_put(clk); > + goto error; > + } > + } > + > + return 0; > + > +error: > + pm_clk_destroy(dev); > + > + return ret; > +} > + > +static int gic_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + const struct gic_clk_data *data; > + struct gic_chip_data *gic; > + int ret, irq; > + > + data = of_device_get_match_data(&pdev->dev); > + if (!data) { > + dev_err(&pdev->dev, "no device match found\n"); > + return -ENODEV; > + } > + > + irq = irq_of_parse_and_map(dev->of_node, 0); > + if (!irq) { > + dev_err(dev, "no parent interrupt found!\n"); > + return -EINVAL; > + } > + > + ret = gic_get_clocks(dev, data); > + if (ret) > + goto irq_dispose; > + > + pm_runtime_enable(dev); > + > + ret = pm_runtime_get_sync(dev); > + if (ret < 0) > + goto rpm_disable; > + > + ret = of_gic_init(dev, &gic); > + if (ret) > + goto rpm_put; > + > + irq_set_chained_handler_and_data(irq, gic_handle_cascade_irq, gic); nit: Rather than exporting the gic_handle_cascade entry point, I'd rather you exported a helper from the GIC driver. Something like: void gic_setup_cascade(int irq, struct gic_data *gic); and do the handler registration there. Alternatively, you could also move the irq parsing and handler registration into of_gic_init, and have this single initialization entry point. > + > + platform_set_drvdata(pdev, gic); > + > + pm_runtime_put(dev); > + > + dev_info(dev, "GIC IRQ controller registered\n"); > + > + return 0; > + > +rpm_put: > + pm_runtime_put_sync(dev); > +rpm_disable: > + pm_runtime_disable(dev); > + pm_clk_destroy(dev); > +irq_dispose: > + irq_dispose_mapping(irq); > + > + return ret; > +} > + > +static const struct dev_pm_ops gic_pm_ops = { > + SET_RUNTIME_PM_OPS(gic_runtime_suspend, > + gic_runtime_resume, NULL) > +}; > + > +static const char * const gic400_clocks[] = { > + "clk", > +}; > + > +static const struct gic_clk_data gic400_data = { > + .num_clocks = ARRAY_SIZE(gic400_clocks), > + .clocks = gic400_clocks, > +}; > + > +static const struct of_device_id gic_match[] = { > + { .compatible = "nvidia,tegra210-agic", .data = &gic400_data }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, gic_match); > + > +static struct platform_driver gic_driver = { > + .probe = gic_probe, > + .driver = { > + .name = "gic", > + .of_match_table = gic_match, > + .pm = &gic_pm_ops, > + } > +}; > + > +builtin_platform_driver(gic_driver); > diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c > index 9f8ab124898b..e65090f7afa4 100644 > --- a/drivers/irqchip/irq-gic.c > +++ b/drivers/irqchip/irq-gic.c > @@ -76,7 +76,7 @@ struct gic_chip_data { > void __iomem *raw_dist_base; > void __iomem *raw_cpu_base; > u32 percpu_offset; > -#ifdef CONFIG_CPU_PM > +#if defined(CONFIG_CPU_PM) || defined(ARM_GIC_PM) Shouldn't that be CONFIG_ARM_GIC_PM? > u32 saved_spi_enable[DIV_ROUND_UP(1020, 32)]; > u32 saved_spi_active[DIV_ROUND_UP(1020, 32)]; > u32 saved_spi_conf[DIV_ROUND_UP(1020, 16)]; > @@ -526,7 +526,7 @@ int gic_cpu_if_down(unsigned int gic_nr) > return 0; > } > > -#ifdef CONFIG_CPU_PM > +#if defined(CONFIG_CPU_PM) || defined(ARM_GIC_PM) Same here? > /* > * Saves the GIC distributor registers during suspend or idle. Must be called > * with interrupts disabled but before powering down the GIC. After calling > @@ -1297,6 +1297,30 @@ error: > return -ENOMEM; > } > > +int of_gic_init(struct device *dev, struct gic_chip_data **gic) > +{ > + int ret; > + > + if (!dev || !dev->of_node || !gic) > + return -EINVAL; > + > + *gic = devm_kzalloc(dev, sizeof(**gic), GFP_KERNEL); > + if (!*gic) > + return -ENOMEM; > + > + gic_init_chip(*gic, dev, dev->of_node->name, false); > + > + ret = gic_of_setup(*gic, dev->of_node); > + if (ret) > + return ret; > + > + ret = gic_init_bases(*gic, -1, &dev->of_node->fwnode); > + if (ret) > + gic_teardown(*gic); > + > + return ret; > +} > + > int __init > gic_of_init(struct device_node *node, struct device_node *parent) > { > @@ -1351,7 +1375,11 @@ IRQCHIP_DECLARE(cortex_a7_gic, "arm,cortex-a7-gic", gic_of_init); > IRQCHIP_DECLARE(msm_8660_qgic, "qcom,msm-8660-qgic", gic_of_init); > IRQCHIP_DECLARE(msm_qgic2, "qcom,msm-qgic2", gic_of_init); > IRQCHIP_DECLARE(pl390, "arm,pl390", gic_of_init); > - > +#else > +int of_gic_init(struct device *dev, struct gic_chip_data **gic) > +{ > + return -ENOTSUPP; > +} > #endif > > #ifdef CONFIG_ACPI > diff --git a/drivers/irqchip/irq-gic.h b/drivers/irqchip/irq-gic.h > index 646e92614b2c..b03ec4bac795 100644 > --- a/drivers/irqchip/irq-gic.h > +++ b/drivers/irqchip/irq-gic.h > @@ -25,4 +25,6 @@ void gic_dist_save(struct gic_chip_data *gic); > void gic_dist_restore(struct gic_chip_data *gic); > void gic_handle_cascade_irq(struct irq_desc *desc); > > +int of_gic_init(struct device *dev, struct gic_chip_data **gic); > + > #endif /* _IRQ_GIC_H */ Otherwise, looks good. Thanks, M. -- Jazz is not dead. It just smells funny. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
