Re: [PATCH V4 4/5] misc/pvpanic: add support to get pvpanic device info by FDT

From: Andy Shevchenko
Date: Wed Oct 31 2018 - 08:50:18 EST


On Wed, Oct 31, 2018 at 7:27 AM Peng Hao <peng.hao2@xxxxxxxxxx> wrote:
>
> By default, when ACPI tables and FDT coexist for ARM64,
> current kernel takes precedence over FDT to get device information.
> Virt machine in qemu provides both FDT and ACPI table. This patch
> increases the way to get information through FDT.
>
> Signed-off-by: Peng Hao <peng.hao2@xxxxxxxxxx>
> ---
> drivers/misc/pvpanic.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++---
> 1 file changed, 64 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/misc/pvpanic.c b/drivers/misc/pvpanic.c
> index d0e28b2..861a0eb 100644
> --- a/drivers/misc/pvpanic.c
> +++ b/drivers/misc/pvpanic.c
> @@ -3,15 +3,18 @@
> * Pvpanic Device Support
> *
> * Copyright (C) 2013 Fujitsu.
> + * Copyright (C) 2018 ZTE.
> */
>
> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>
> +#include <linux/acpi.h>
> #include <linux/kernel.h>
> #include <linux/module.h>
> -#include <linux/init.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> #include <linux/types.h>
> -#include <linux/acpi.h>
>
> MODULE_AUTHOR("Hu Tao <hutao@xxxxxxxxxxxxxx>");
> MODULE_DESCRIPTION("pvpanic device driver");
> @@ -22,7 +25,7 @@
>
> static const struct acpi_device_id pvpanic_device_ids[] = {
> { "QEMU0001", 0 },
> - { "", 0 },
> + { "", 0 }
> };
> MODULE_DEVICE_TABLE(acpi, pvpanic_device_ids);
>
> @@ -60,6 +63,32 @@
> .priority = 1, /* let this called before broken drm_fb_helper */
> };
>
> +static int pvpanic_mmio_probe(struct platform_device *pdev)
> +{
> + struct resource *mem;
> +
> + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!mem)
> + return -EINVAL;
> +
> + base = devm_ioremap_resource(&pdev->dev, mem);
> + if (base == NULL)
> + return -EFAULT;
> +
> + atomic_notifier_chain_register(&panic_notifier_list,
> + &pvpanic_panic_nb);
> +
> + return 0;
> +}
> +
> +static int pvpanic_mmio_remove(struct platform_device *pdev)
> +{
> +
> + atomic_notifier_chain_unregister(&panic_notifier_list,
> + &pvpanic_panic_nb);
> +
> + return 0;
> +}
>
> static acpi_status
> pvpanic_walk_resources(struct acpi_resource *res, void *context)
> @@ -120,4 +149,35 @@ static int pvpanic_remove(struct acpi_device *device)
> return 0;
> }
>
> -module_acpi_driver(pvpanic_driver);
> +static const struct of_device_id pvpanic_mmio_match[] = {
> + { .compatible = "qemu,pvpanic-mmio", },
> + {}
> +};
> +
> +static struct platform_driver pvpanic_mmio_driver = {
> + .driver = {
> + .name = "pvpanic-mmio",
> + .of_match_table = pvpanic_mmio_match,
> + },
> + .probe = pvpanic_mmio_probe,
> + .remove = pvpanic_mmio_remove,
> +};
> +
> +static int __init pvpanic_mmio_init(void)
> +{
> + if (acpi_disabled)
> + return platform_driver_register(&pvpanic_mmio_driver);
> + else
> + return acpi_bus_register_driver(&pvpanic_driver);
> +}
> +
> +static void __exit pvpanic_mmio_exit(void)
> +{
> + if (acpi_disabled)
> + platform_driver_unregister(&pvpanic_mmio_driver);
> + else
> + acpi_bus_unregister_driver(&pvpanic_driver);
> +}
> +
> +module_init(pvpanic_mmio_init);
> +module_exit(pvpanic_mmio_exit);
> --
> 1.8.3.1
>


--
With Best Regards,
Andy Shevchenko