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Commit ad5fb870 authored by Dan Williams's avatar Dan Williams
Browse files

e820, efi: add ACPI 6.0 persistent memory types 



ACPI 6.0 formalizes e820-type-7 and efi-type-14 as persistent memory.
Mark it "reserved" and allow it to be claimed by a persistent memory
device driver.

This definition is in addition to the Linux kernel's existing type-12
definition that was recently added in support of shipping platforms with
NVDIMM support that predate ACPI 6.0 (which now classifies type-12 as
OEM reserved).

Note, /proc/iomem can be consulted for differentiating legacy
"Persistent Memory (legacy)" E820_PRAM vs standard "Persistent Memory"
E820_PMEM.

Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarJeff Moyer <jmoyer@redhat.com>
Acked-by: default avatarAndy Lutomirski <luto@amacapital.net>
Reviewed-by: default avatarRoss Zwisler <ross.zwisler@linux.intel.com>
Acked-by: default avatarChristoph Hellwig <hch@lst.de>
Tested-by: default avatarToshi Kani <toshi.kani@hp.com>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent f3b6ced2

arch/arm64/kernel/efi.c

+1 −0
Original line number Diff line number Diff line
@@ -158,6 +158,7 @@ static __init int is_reserve_region(efi_memory_desc_t *md) 
	case EFI_BOOT_SERVICES_CODE:

	case EFI_BOOT_SERVICES_DATA:

	case EFI_CONVENTIONAL_MEMORY:

	case EFI_PERSISTENT_MEMORY:

		return 0;

	default:

		break;

arch/ia64/kernel/efi.c

+4 −0
Original line number Diff line number Diff line
@@ -1223,6 +1223,10 @@ efi_initialize_iomem_resources(struct resource *code_resource, 
				flags |= IORESOURCE_DISABLED;

				break;



			case EFI_PERSISTENT_MEMORY:

				name = "Persistent Memory";

				break;



			case EFI_RESERVED_TYPE:

			case EFI_RUNTIME_SERVICES_CODE:

			case EFI_RUNTIME_SERVICES_DATA:

arch/x86/boot/compressed/eboot.c

+4 −0
Original line number Diff line number Diff line
@@ -1224,6 +1224,10 @@ static efi_status_t setup_e820(struct boot_params *params, 
			e820_type = E820_NVS;

			break;



		case EFI_PERSISTENT_MEMORY:

			e820_type = E820_PMEM;

			break;



		default:

			continue;

		}

arch/x86/include/uapi/asm/e820.h

+1 −0
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ 
#define E820_ACPI	3

#define E820_NVS	4

#define E820_UNUSABLE	5

#define E820_PMEM	7



/*

 * This is a non-standardized way to represent ADR or NVDIMM regions that

arch/x86/kernel/e820.c

+24 −4
Original line number Diff line number Diff line
@@ -149,6 +149,7 @@ static void __init e820_print_type(u32 type) 
	case E820_UNUSABLE:

		printk(KERN_CONT "unusable");

		break;

	case E820_PMEM:

	case E820_PRAM:

		printk(KERN_CONT "persistent (type %u)", type);

		break;
@@ -918,11 +919,32 @@ static inline const char *e820_type_to_string(int e820_type) 
	case E820_ACPI:	return "ACPI Tables";

	case E820_NVS:	return "ACPI Non-volatile Storage";

	case E820_UNUSABLE:	return "Unusable memory";

	case E820_PRAM: return "Persistent RAM";

	case E820_PRAM: return "Persistent Memory (legacy)";

	case E820_PMEM: return "Persistent Memory";

	default:	return "reserved";

	}

}



static bool do_mark_busy(u32 type, struct resource *res)

{

	/* this is the legacy bios/dos rom-shadow + mmio region */

	if (res->start < (1ULL<<20))

		return true;



	/*

	 * Treat persistent memory like device memory, i.e. reserve it

	 * for exclusive use of a driver

	 */

	switch (type) {

	case E820_RESERVED:

	case E820_PRAM:

	case E820_PMEM:

		return false;

	default:

		return true;

	}

}



/*

 * Mark e820 reserved areas as busy for the resource manager.

 */
@@ -952,9 +974,7 @@ void __init e820_reserve_resources(void) 
		 * pci device BAR resource and insert them later in

		 * pcibios_resource_survey()

		 */

		if (((e820.map[i].type != E820_RESERVED) &&

		     (e820.map[i].type != E820_PRAM)) ||

		     res->start < (1ULL<<20)) {

		if (do_mark_busy(e820.map[i].type, res)) {

			res->flags |= IORESOURCE_BUSY;

			insert_resource(&iomem_resource, res);

		}