arch/powerpc/include/asm/drmem.h

Source file repositories/reference/linux-study-clean/arch/powerpc/include/asm/drmem.h

File Facts

System
Linux kernel
Corpus path
arch/powerpc/include/asm/drmem.h
Extension
.h
Size
3008 bytes
Lines
126
Domain
Architecture Layer
Bucket
arch/powerpc
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

struct drmem_lmb {
	u64     base_addr;
	u32     drc_index;
	u32     aa_index;
	u32     flags;
};

struct drmem_lmb_info {
	struct drmem_lmb        *lmbs;
	int                     n_lmbs;
	u64                     lmb_size;
};

struct device_node;
struct property;

extern struct drmem_lmb_info *drmem_info;

static inline struct drmem_lmb *drmem_lmb_next(struct drmem_lmb *lmb,
					       const struct drmem_lmb *start)
{
	/*
	 * DLPAR code paths can take several milliseconds per element
	 * when interacting with firmware. Ensure that we don't
	 * unfairly monopolize the CPU.
	 */
	if (((++lmb - start) % 16) == 0)
		cond_resched();

	return lmb;
}

#define for_each_drmem_lmb_in_range(lmb, start, end)		\
	for ((lmb) = (start); (lmb) < (end); lmb = drmem_lmb_next(lmb, start))

#define for_each_drmem_lmb(lmb)					\
	for_each_drmem_lmb_in_range((lmb),			\
		&drmem_info->lmbs[0],				\
		&drmem_info->lmbs[drmem_info->n_lmbs])

/*
 * The of_drconf_cell_v1 struct defines the layout of the LMB data
 * specified in the ibm,dynamic-memory device tree property.
 * The property itself is a 32-bit value specifying the number of
 * LMBs followed by an array of of_drconf_cell_v1 entries, one
 * per LMB.
 */
struct of_drconf_cell_v1 {
	__be64	base_addr;
	__be32	drc_index;
	__be32	reserved;
	__be32	aa_index;
	__be32	flags;
};

/*
 * Version 2 of the ibm,dynamic-memory property is defined as a
 * 32-bit value specifying the number of LMB sets followed by an
 * array of of_drconf_cell_v2 entries, one per LMB set.
 */
struct of_drconf_cell_v2 {
	u32	seq_lmbs;
	u64	base_addr;
	u32	drc_index;
	u32	aa_index;
	u32	flags;
} __packed;

#define DRCONF_MEM_ASSIGNED	0x00000008
#define DRCONF_MEM_AI_INVALID	0x00000040
#define DRCONF_MEM_RESERVED	0x00000080
#define DRCONF_MEM_HOTREMOVABLE	0x00000100

static inline u64 drmem_lmb_size(void)
{
	return drmem_info->lmb_size;
}

#define DRMEM_LMB_RESERVED	0x80000000

static inline void drmem_mark_lmb_reserved(struct drmem_lmb *lmb)
{
	lmb->flags |= DRMEM_LMB_RESERVED;
}

static inline void drmem_remove_lmb_reservation(struct drmem_lmb *lmb)
{
	lmb->flags &= ~DRMEM_LMB_RESERVED;
}

Annotation

Implementation Notes