1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * SBI initialilization and all extension implementation.
4  *
5  * Copyright (c) 2020 Western Digital Corporation or its affiliates.
6  *
7  * Taken from Linux arch/riscv/kernel/sbi.c
8  */
9 
10 #include <common.h>
11 #include <asm/encoding.h>
12 #include <asm/sbi.h>
13 
sbi_ecall(int ext,int fid,unsigned long arg0,unsigned long arg1,unsigned long arg2,unsigned long arg3,unsigned long arg4,unsigned long arg5)14 struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0,
15 			unsigned long arg1, unsigned long arg2,
16 			unsigned long arg3, unsigned long arg4,
17 			unsigned long arg5)
18 {
19 	struct sbiret ret;
20 
21 	register uintptr_t a0 asm ("a0") = (uintptr_t)(arg0);
22 	register uintptr_t a1 asm ("a1") = (uintptr_t)(arg1);
23 	register uintptr_t a2 asm ("a2") = (uintptr_t)(arg2);
24 	register uintptr_t a3 asm ("a3") = (uintptr_t)(arg3);
25 	register uintptr_t a4 asm ("a4") = (uintptr_t)(arg4);
26 	register uintptr_t a5 asm ("a5") = (uintptr_t)(arg5);
27 	register uintptr_t a6 asm ("a6") = (uintptr_t)(fid);
28 	register uintptr_t a7 asm ("a7") = (uintptr_t)(ext);
29 	asm volatile ("ecall"
30 		      : "+r" (a0), "+r" (a1)
31 		      : "r" (a2), "r" (a3), "r" (a4), "r" (a5), "r" (a6), "r" (a7)
32 		      : "memory");
33 	ret.error = a0;
34 	ret.value = a1;
35 
36 	return ret;
37 }
38 
39 /**
40  * sbi_set_timer() - Program the timer for next timer event.
41  * @stime_value: The value after which next timer event should fire.
42  *
43  * Return: None
44  */
sbi_set_timer(uint64_t stime_value)45 void sbi_set_timer(uint64_t stime_value)
46 {
47 #if __riscv_xlen == 32
48 	sbi_ecall(SBI_EXT_SET_TIMER, SBI_FID_SET_TIMER, stime_value,
49 		  stime_value >> 32, 0, 0, 0, 0);
50 #else
51 	sbi_ecall(SBI_EXT_SET_TIMER, SBI_FID_SET_TIMER, stime_value,
52 		  0, 0, 0, 0, 0);
53 #endif
54 }
55 
56 /**
57  * sbi_probe_extension() - Check if an SBI extension ID is supported or not.
58  * @extid: The extension ID to be probed.
59  *
60  * Return: Extension specific nonzero value f yes, -ENOTSUPP otherwise.
61  */
sbi_probe_extension(int extid)62 int sbi_probe_extension(int extid)
63 {
64 	struct sbiret ret;
65 
66 	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_PROBE_EXT, extid,
67 			0, 0, 0, 0, 0);
68 	if (!ret.error)
69 		if (ret.value)
70 			return ret.value;
71 
72 	return -ENOTSUPP;
73 }
74 
75 #ifdef CONFIG_SBI_V01
76 
77 /**
78  * sbi_console_putchar() - Writes given character to the console device.
79  * @ch: The data to be written to the console.
80  *
81  * Return: None
82  */
sbi_console_putchar(int ch)83 void sbi_console_putchar(int ch)
84 {
85 	sbi_ecall(SBI_EXT_0_1_CONSOLE_PUTCHAR, 0, ch, 0, 0, 0, 0, 0);
86 }
87 
88 /**
89  * sbi_console_getchar() - Reads a byte from console device.
90  *
91  * Returns the value read from console.
92  */
sbi_console_getchar(void)93 int sbi_console_getchar(void)
94 {
95 	struct sbiret ret;
96 
97 	ret = sbi_ecall(SBI_EXT_0_1_CONSOLE_GETCHAR, 0, 0, 0, 0, 0, 0, 0);
98 
99 	return ret.error;
100 }
101 
102 /**
103  * sbi_clear_ipi() - Clear any pending IPIs for the calling hart.
104  *
105  * Return: None
106  */
sbi_clear_ipi(void)107 void sbi_clear_ipi(void)
108 {
109 	sbi_ecall(SBI_EXT_0_1_CLEAR_IPI, 0, 0, 0, 0, 0, 0, 0);
110 }
111 
112 /**
113  * sbi_shutdown() - Remove all the harts from executing supervisor code.
114  *
115  * Return: None
116  */
sbi_shutdown(void)117 void sbi_shutdown(void)
118 {
119 	sbi_ecall(SBI_EXT_0_1_SHUTDOWN, 0, 0, 0, 0, 0, 0, 0);
120 }
121 
122 /**
123  * sbi_send_ipi() - Send an IPI to any hart.
124  * @hart_mask: A cpu mask containing all the target harts.
125  *
126  * Return: None
127  */
sbi_send_ipi(const unsigned long * hart_mask)128 void sbi_send_ipi(const unsigned long *hart_mask)
129 {
130 	sbi_ecall(SBI_EXT_SEND_IPI, SBI_FID_SEND_IPI, (unsigned long)hart_mask,
131 		  0, 0, 0, 0, 0);
132 }
133 
134 /**
135  * sbi_remote_fence_i() - Execute FENCE.I instruction on given remote harts.
136  * @hart_mask: A cpu mask containing all the target harts.
137  *
138  * Return: None
139  */
sbi_remote_fence_i(const unsigned long * hart_mask)140 void sbi_remote_fence_i(const unsigned long *hart_mask)
141 {
142 	sbi_ecall(SBI_EXT_REMOTE_FENCE_I, SBI_FID_REMOTE_FENCE_I,
143 		  (unsigned long)hart_mask, 0, 0, 0, 0, 0);
144 }
145 
146 /**
147  * sbi_remote_sfence_vma() - Execute SFENCE.VMA instructions on given remote
148  *			     harts for the specified virtual address range.
149  * @hart_mask: A cpu mask containing all the target harts.
150  * @start: Start of the virtual address
151  * @size: Total size of the virtual address range.
152  *
153  * Return: None
154  */
sbi_remote_sfence_vma(const unsigned long * hart_mask,unsigned long start,unsigned long size)155 void sbi_remote_sfence_vma(const unsigned long *hart_mask,
156 			   unsigned long start,
157 			   unsigned long size)
158 {
159 	sbi_ecall(SBI_EXT_REMOTE_SFENCE_VMA, SBI_FID_REMOTE_SFENCE_VMA,
160 		  (unsigned long)hart_mask, start, size, 0, 0, 0);
161 }
162 
163 /**
164  * sbi_remote_sfence_vma_asid() - Execute SFENCE.VMA instructions on given
165  * remote harts for a virtual address range belonging to a specific ASID.
166  *
167  * @hart_mask: A cpu mask containing all the target harts.
168  * @start: Start of the virtual address
169  * @size: Total size of the virtual address range.
170  * @asid: The value of address space identifier (ASID).
171  *
172  * Return: None
173  */
sbi_remote_sfence_vma_asid(const unsigned long * hart_mask,unsigned long start,unsigned long size,unsigned long asid)174 void sbi_remote_sfence_vma_asid(const unsigned long *hart_mask,
175 				unsigned long start,
176 				unsigned long size,
177 				unsigned long asid)
178 {
179 	sbi_ecall(SBI_EXT_REMOTE_SFENCE_VMA_ASID,
180 		  SBI_FID_REMOTE_SFENCE_VMA_ASID,
181 		  (unsigned long)hart_mask, start, size, asid, 0, 0);
182 }
183 
184 #endif /* CONFIG_SBI_V01 */
185