xref: /openbmc/linux/arch/powerpc/include/asm/drmem.h (revision 99b75eb7)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * drmem.h: Power specific logical memory block representation
4  *
5  * Copyright 2017 IBM Corporation
6  */
7 
8 #ifndef _ASM_POWERPC_LMB_H
9 #define _ASM_POWERPC_LMB_H
10 
11 #include <linux/sched.h>
12 
13 struct drmem_lmb {
14 	u64     base_addr;
15 	u32     drc_index;
16 	u32     aa_index;
17 	u32     flags;
18 };
19 
20 struct drmem_lmb_info {
21 	struct drmem_lmb        *lmbs;
22 	int                     n_lmbs;
23 	u64                     lmb_size;
24 };
25 
26 extern struct drmem_lmb_info *drmem_info;
27 
28 static inline struct drmem_lmb *drmem_lmb_next(struct drmem_lmb *lmb,
29 					       const struct drmem_lmb *start)
30 {
31 	/*
32 	 * DLPAR code paths can take several milliseconds per element
33 	 * when interacting with firmware. Ensure that we don't
34 	 * unfairly monopolize the CPU.
35 	 */
36 	if (((++lmb - start) % 16) == 0)
37 		cond_resched();
38 
39 	return lmb;
40 }
41 
42 #define for_each_drmem_lmb_in_range(lmb, start, end)		\
43 	for ((lmb) = (start); (lmb) < (end); lmb = drmem_lmb_next(lmb, start))
44 
45 #define for_each_drmem_lmb(lmb)					\
46 	for_each_drmem_lmb_in_range((lmb),			\
47 		&drmem_info->lmbs[0],				\
48 		&drmem_info->lmbs[drmem_info->n_lmbs])
49 
50 /*
51  * The of_drconf_cell_v1 struct defines the layout of the LMB data
52  * specified in the ibm,dynamic-memory device tree property.
53  * The property itself is a 32-bit value specifying the number of
54  * LMBs followed by an array of of_drconf_cell_v1 entries, one
55  * per LMB.
56  */
57 struct of_drconf_cell_v1 {
58 	__be64	base_addr;
59 	__be32	drc_index;
60 	__be32	reserved;
61 	__be32	aa_index;
62 	__be32	flags;
63 };
64 
65 /*
66  * Version 2 of the ibm,dynamic-memory property is defined as a
67  * 32-bit value specifying the number of LMB sets followed by an
68  * array of of_drconf_cell_v2 entries, one per LMB set.
69  */
70 struct of_drconf_cell_v2 {
71 	u32	seq_lmbs;
72 	u64	base_addr;
73 	u32	drc_index;
74 	u32	aa_index;
75 	u32	flags;
76 } __packed;
77 
78 #define DRCONF_MEM_ASSIGNED	0x00000008
79 #define DRCONF_MEM_AI_INVALID	0x00000040
80 #define DRCONF_MEM_RESERVED	0x00000080
81 #define DRCONF_MEM_HOTREMOVABLE	0x00000100
82 
83 static inline u64 drmem_lmb_size(void)
84 {
85 	return drmem_info->lmb_size;
86 }
87 
88 #define DRMEM_LMB_RESERVED	0x80000000
89 
90 static inline void drmem_mark_lmb_reserved(struct drmem_lmb *lmb)
91 {
92 	lmb->flags |= DRMEM_LMB_RESERVED;
93 }
94 
95 static inline void drmem_remove_lmb_reservation(struct drmem_lmb *lmb)
96 {
97 	lmb->flags &= ~DRMEM_LMB_RESERVED;
98 }
99 
100 static inline bool drmem_lmb_reserved(struct drmem_lmb *lmb)
101 {
102 	return lmb->flags & DRMEM_LMB_RESERVED;
103 }
104 
105 u64 drmem_lmb_memory_max(void);
106 int walk_drmem_lmbs(struct device_node *dn, void *data,
107 		    int (*func)(struct drmem_lmb *, const __be32 **, void *));
108 int drmem_update_dt(void);
109 
110 #ifdef CONFIG_PPC_PSERIES
111 int __init
112 walk_drmem_lmbs_early(unsigned long node, void *data,
113 		      int (*func)(struct drmem_lmb *, const __be32 **, void *));
114 #endif
115 
116 static inline void invalidate_lmb_associativity_index(struct drmem_lmb *lmb)
117 {
118 	lmb->aa_index = 0xffffffff;
119 }
120 
121 #endif /* _ASM_POWERPC_LMB_H */
122