mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-21 08:46:49 +07:00
a6c7f4c6ae
Platform firmware like EFI/ACPI may publish "hmem" platform devices. Such a device is a performance differentiated memory range likely reserved for an application specific use case. The driver gives access to 100% of the capacity via a device-dax mmap instance by default. However, if over-subscription and other kernel memory management is desired the resulting dax device can be assigned to the core-mm via the kmem driver. This consumes "hmem" devices the producer of "hmem" devices is saved for a follow-on patch so that it can reference the new CONFIG_DEV_DAX_HMEM symbol to gate performing the enumeration work. Reported-by: kbuild test robot <lkp@intel.com> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
57 lines
1.3 KiB
C
57 lines
1.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <linux/platform_device.h>
|
|
#include <linux/memregion.h>
|
|
#include <linux/module.h>
|
|
#include <linux/pfn_t.h>
|
|
#include "bus.h"
|
|
|
|
static int dax_hmem_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct dev_pagemap pgmap = { };
|
|
struct dax_region *dax_region;
|
|
struct memregion_info *mri;
|
|
struct dev_dax *dev_dax;
|
|
struct resource *res;
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
if (!res)
|
|
return -ENOMEM;
|
|
|
|
mri = dev->platform_data;
|
|
memcpy(&pgmap.res, res, sizeof(*res));
|
|
|
|
dax_region = alloc_dax_region(dev, pdev->id, res, mri->target_node,
|
|
PMD_SIZE, PFN_DEV|PFN_MAP);
|
|
if (!dax_region)
|
|
return -ENOMEM;
|
|
|
|
dev_dax = devm_create_dev_dax(dax_region, 0, &pgmap);
|
|
if (IS_ERR(dev_dax))
|
|
return PTR_ERR(dev_dax);
|
|
|
|
/* child dev_dax instances now own the lifetime of the dax_region */
|
|
dax_region_put(dax_region);
|
|
return 0;
|
|
}
|
|
|
|
static int dax_hmem_remove(struct platform_device *pdev)
|
|
{
|
|
/* devm handles teardown */
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver dax_hmem_driver = {
|
|
.probe = dax_hmem_probe,
|
|
.remove = dax_hmem_remove,
|
|
.driver = {
|
|
.name = "hmem",
|
|
},
|
|
};
|
|
|
|
module_platform_driver(dax_hmem_driver);
|
|
|
|
MODULE_ALIAS("platform:hmem*");
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_AUTHOR("Intel Corporation");
|