xref: /openbmc/linux/arch/powerpc/include/asm/drmem.h (revision 0c6dfa75)
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 struct device_node;
27 struct property;
28 
29 extern struct drmem_lmb_info *drmem_info;
30 
31 static inline struct drmem_lmb *drmem_lmb_next(struct drmem_lmb *lmb,
32 					       const struct drmem_lmb *start)
33 {
34 	/*
35 	 * DLPAR code paths can take several milliseconds per element
36 	 * when interacting with firmware. Ensure that we don't
37 	 * unfairly monopolize the CPU.
38 	 */
39 	if (((++lmb - start) % 16) == 0)
40 		cond_resched();
41 
42 	return lmb;
43 }
44 
45 #define for_each_drmem_lmb_in_range(lmb, start, end)		\
46 	for ((lmb) = (start); (lmb) < (end); lmb = drmem_lmb_next(lmb, start))
47 
48 #define for_each_drmem_lmb(lmb)					\
49 	for_each_drmem_lmb_in_range((lmb),			\
50 		&drmem_info->lmbs[0],				\
51 		&drmem_info->lmbs[drmem_info->n_lmbs])
52 
53 /*
54  * The of_drconf_cell_v1 struct defines the layout of the LMB data
55  * specified in the ibm,dynamic-memory device tree property.
56  * The property itself is a 32-bit value specifying the number of
57  * LMBs followed by an array of of_drconf_cell_v1 entries, one
58  * per LMB.
59  */
60 struct of_drconf_cell_v1 {
61 	__be64	base_addr;
62 	__be32	drc_index;
63 	__be32	reserved;
64 	__be32	aa_index;
65 	__be32	flags;
66 };
67 
68 /*
69  * Version 2 of the ibm,dynamic-memory property is defined as a
70  * 32-bit value specifying the number of LMB sets followed by an
71  * array of of_drconf_cell_v2 entries, one per LMB set.
72  */
73 struct of_drconf_cell_v2 {
74 	u32	seq_lmbs;
75 	u64	base_addr;
76 	u32	drc_index;
77 	u32	aa_index;
78 	u32	flags;
79 } __packed;
80 
81 #define DRCONF_MEM_ASSIGNED	0x00000008
82 #define DRCONF_MEM_AI_INVALID	0x00000040
83 #define DRCONF_MEM_RESERVED	0x00000080
84 #define DRCONF_MEM_HOTREMOVABLE	0x00000100
85 
86 static inline u64 drmem_lmb_size(void)
87 {
88 	return drmem_info->lmb_size;
89 }
90 
91 #define DRMEM_LMB_RESERVED	0x80000000
92 
93 static inline void drmem_mark_lmb_reserved(struct drmem_lmb *lmb)
94 {
95 	lmb->flags |= DRMEM_LMB_RESERVED;
96 }
97 
98 static inline void drmem_remove_lmb_reservation(struct drmem_lmb *lmb)
99 {
100 	lmb->flags &= ~DRMEM_LMB_RESERVED;
101 }
102 
103 static inline bool drmem_lmb_reserved(struct drmem_lmb *lmb)
104 {
105 	return lmb->flags & DRMEM_LMB_RESERVED;
106 }
107 
108 u64 drmem_lmb_memory_max(void);
109 int walk_drmem_lmbs(struct device_node *dn, void *data,
110 		    int (*func)(struct drmem_lmb *, const __be32 **, void *));
111 int drmem_update_dt(void);
112 
113 #ifdef CONFIG_PPC_PSERIES
114 int __init
115 walk_drmem_lmbs_early(unsigned long node, void *data,
116 		      int (*func)(struct drmem_lmb *, const __be32 **, void *));
117 void drmem_update_lmbs(struct property *prop);
118 #endif
119 
120 static inline void invalidate_lmb_associativity_index(struct drmem_lmb *lmb)
121 {
122 	lmb->aa_index = 0xffffffff;
123 }
124 
125 #endif /* _ASM_POWERPC_LMB_H */
126