[PATCH v9 2/4] irqchip: add platform device driver for mbigen device
Marc Zyngier
marc.zyngier at arm.com
Thu Dec 3 08:22:23 PST 2015
On 23/11/15 03:15, MaJun wrote:
> From: Ma Jun <majun258 at huawei.com>
>
> Mbigen means Message Based Interrupt Generator(MBIGEN).
>
> Its a kind of interrupt controller that collects
> the interrupts from external devices and generate msi interrupt.
> Mbigen is applied to reduce the number of wire connected interrupts.
>
> As the peripherals increasing, the interrupts lines needed is
> increasing much, especially on the Arm64 server SOC.
>
> Therefore, the interrupt pin in GIC is not enough to cover so
> many peripherals.
>
> Mbigen is designed to fix this problem.
>
> Mbigen chip locates in ITS or outside of ITS.
>
> Mbigen chip hardware structure shows as below:
>
> mbigen chip
> |---------------------|-------------------|
> mgn_node0 mgn_node1 mgn_node2
> | |-------| |-------|------|
> dev1 dev1 dev2 dev1 dev3 dev4
>
> Each mbigen chip contains several mbigen nodes.
>
> External devices can connect to mbigen node through wire connecting way.
>
> Because a mbigen node only can support 128 interrupt maximum, depends
> on the interrupt lines number of devices, a device can connects to one
> more mbigen nodes.
>
> Also, several different devices can connect to a same mbigen node.
>
> When devices triggered interrupt,mbigen chip detects and collects
> the interrupts and generates the MBI interrupts by writing the ITS
> Translator register.
>
> To simplify mbigen driver,I used a new conception--mbigen device.
> Each mbigen device is initialized as a platform device.
>
> Mbigen device presents the parts(register, pin definition etc.) in
> mbigen chip corresponding to a peripheral device.
>
> So from software view, the structure likes below
>
> mbigen chip
> |---------------------|-----------------|
> mbigen device1 mbigen device2 mbigen device3
> | | |
> dev1 dev2 dev3
> Signed-off-by: Ma Jun <majun258 at huawei.com>
> ---
> drivers/irqchip/Kconfig | 8 ++++
> drivers/irqchip/Makefile | 1 +
> drivers/irqchip/irq-mbigen.c | 78 ++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 87 insertions(+), 0 deletions(-)
> create mode 100644 drivers/irqchip/irq-mbigen.c
>
> diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
> index 4d7294e..b205e15 100644
> --- a/drivers/irqchip/Kconfig
> +++ b/drivers/irqchip/Kconfig
> @@ -27,6 +27,14 @@ config ARM_GIC_V3_ITS
> bool
> select PCI_MSI_IRQ_DOMAIN
>
> +config HISILICON_IRQ_MBIGEN
> + bool "Support mbigen interrupt controller"
> + default n
> + depends on ARM_GIC_V3 && ARM_GIC_V3_ITS && GENERIC_MSI_IRQ_DOMAIN
> + help
> + Enable the mbigen interrupt controller used on
> + Hisilicon platform.
> +
> config ARM_NVIC
> bool
> select IRQ_DOMAIN
> diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
> index 177f78f..cd76b11 100644
> --- a/drivers/irqchip/Makefile
> +++ b/drivers/irqchip/Makefile
> @@ -24,6 +24,7 @@ obj-$(CONFIG_ARM_GIC) += irq-gic.o irq-gic-common.o
> obj-$(CONFIG_ARM_GIC_V2M) += irq-gic-v2m.o
> obj-$(CONFIG_ARM_GIC_V3) += irq-gic-v3.o irq-gic-common.o
> obj-$(CONFIG_ARM_GIC_V3_ITS) += irq-gic-v3-its.o irq-gic-v3-its-pci-msi.o irq-gic-v3-its-platform-msi.o
> +obj-$(CONFIG_HISILICON_IRQ_MBIGEN) += irq-mbigen.o
> obj-$(CONFIG_ARM_NVIC) += irq-nvic.o
> obj-$(CONFIG_ARM_VIC) += irq-vic.o
> obj-$(CONFIG_ATMEL_AIC_IRQ) += irq-atmel-aic-common.o irq-atmel-aic.o
> diff --git a/drivers/irqchip/irq-mbigen.c b/drivers/irqchip/irq-mbigen.c
> new file mode 100644
> index 0000000..9f036c2
> --- /dev/null
> +++ b/drivers/irqchip/irq-mbigen.c
> @@ -0,0 +1,78 @@
> +/*
> + * Copyright (C) 2015 Hisilicon Limited, All Rights Reserved.
> + * Author: Jun Ma <majun258 at huawei.com>
> + * Author: Yun Wu <wuyun.wu at huawei.com>
> + *
> + * 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/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +/**
> + * struct mbigen_device - holds the information of mbigen device.
> + *
> + * @pdev: pointer to the platform device structure of mbigen chip.
> + * @base: mapped address of this mbigen chip.
> + */
> +struct mbigen_device {
> + struct platform_device *pdev;
> + void __iomem *base;
> +};
> +
> +static int mbigen_device_probe(struct platform_device *pdev)
> +{
> + struct mbigen_device *mgn_chip;
> + struct resource *res;
> +
> + mgn_chip = devm_kzalloc(&pdev->dev, sizeof(*mgn_chip), GFP_KERNEL);
> + if (!mgn_chip)
> + return -ENOMEM;
> +
> + mgn_chip->pdev = pdev;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + mgn_chip->base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(mgn_chip->base))
> + return PTR_ERR(mgn_chip->base);
> +
> + platform_set_drvdata(pdev, mgn_chip);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id mbigen_of_match[] = {
> + { .compatible = "hisilicon,mbigen-v2" },
> + { /* END */ }
> +};
> +MODULE_DEVICE_TABLE(of, mbigen_of_match);
> +
> +static struct platform_driver mbigen_platform_driver = {
> + .driver = {
> + .name = "Hisilicon MBIGEN-V2",
> + .owner = THIS_MODULE,
> + .of_match_table = mbigen_of_match,
> + },
> + .probe = mbigen_device_probe,
> +};
> +
> +module_platform_driver(mbigen_platform_driver);
> +
> +MODULE_AUTHOR("Jun Ma <majun258 at huawei.com>");
> +MODULE_AUTHOR("Yun Wu <wuyun.wu at huawei.com>");
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("Hisilicon MBI Generator driver");
>
Reviewed-by: Marc Zyngier <marc.zyngier at arm.com>
M.
--
Jazz is not dead. It just smells funny...
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