xref: /linux/arch/arm64/include/asm/rsi.h (revision e814f3fd16acfb7f9966773953de8f740a1e3202)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2024 ARM Ltd.
4  */
5 
6 #ifndef __ASM_RSI_H_
7 #define __ASM_RSI_H_
8 
9 #include <linux/errno.h>
10 #include <linux/jump_label.h>
11 #include <asm/rsi_cmds.h>
12 
13 #define RSI_PDEV_NAME "arm-cca-dev"
14 
15 DECLARE_STATIC_KEY_FALSE(rsi_present);
16 
17 void __init arm64_rsi_init(void);
18 
19 bool __arm64_is_protected_mmio(phys_addr_t base, size_t size);
20 
21 static inline bool is_realm_world(void)
22 {
23 	return static_branch_unlikely(&rsi_present);
24 }
25 
26 static inline int rsi_set_memory_range(phys_addr_t start, phys_addr_t end,
27 				       enum ripas state, unsigned long flags)
28 {
29 	unsigned long ret;
30 	phys_addr_t top;
31 
32 	while (start != end) {
33 		ret = rsi_set_addr_range_state(start, end, state, flags, &top);
34 		if (ret || top < start || top > end)
35 			return -EINVAL;
36 		start = top;
37 	}
38 
39 	return 0;
40 }
41 
42 /*
43  * Convert the specified range to RAM. Do not use this if you rely on the
44  * contents of a page that may already be in RAM state.
45  */
46 static inline int rsi_set_memory_range_protected(phys_addr_t start,
47 						 phys_addr_t end)
48 {
49 	return rsi_set_memory_range(start, end, RSI_RIPAS_RAM,
50 				    RSI_CHANGE_DESTROYED);
51 }
52 
53 /*
54  * Convert the specified range to RAM. Do not convert any pages that may have
55  * been DESTROYED, without our permission.
56  */
57 static inline int rsi_set_memory_range_protected_safe(phys_addr_t start,
58 						      phys_addr_t end)
59 {
60 	return rsi_set_memory_range(start, end, RSI_RIPAS_RAM,
61 				    RSI_NO_CHANGE_DESTROYED);
62 }
63 
64 static inline int rsi_set_memory_range_shared(phys_addr_t start,
65 					      phys_addr_t end)
66 {
67 	return rsi_set_memory_range(start, end, RSI_RIPAS_EMPTY,
68 				    RSI_CHANGE_DESTROYED);
69 }
70 #endif /* __ASM_RSI_H_ */
71