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 <errno.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_get_spec_version() - get current SBI specification version
58  *
59  * Return: version id
60  */
sbi_get_spec_version(void)61 long sbi_get_spec_version(void)
62 {
63 	struct sbiret ret;
64 
65 	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_SPEC_VERSION,
66 			0, 0, 0, 0, 0, 0);
67 	if (!ret.error)
68 		if (ret.value)
69 			return ret.value;
70 
71 	return -ENOTSUPP;
72 }
73 
74 /**
75  * sbi_get_impl_id() - get SBI implementation ID
76  *
77  * Return: implementation ID
78  */
sbi_get_impl_id(void)79 int sbi_get_impl_id(void)
80 {
81 	struct sbiret ret;
82 
83 	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_IMP_ID,
84 			0, 0, 0, 0, 0, 0);
85 	if (!ret.error)
86 		if (ret.value)
87 			return ret.value;
88 
89 	return -ENOTSUPP;
90 }
91 
92 /**
93  * sbi_get_impl_version() - get SBI implementation version
94  *
95  * @version:	pointer to receive version
96  * Return:	0 on success, -ENOTSUPP otherwise
97  */
sbi_get_impl_version(long * version)98 int sbi_get_impl_version(long *version)
99 {
100 	struct sbiret ret;
101 
102 	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_IMP_VERSION,
103 			0, 0, 0, 0, 0, 0);
104 	if (ret.error)
105 		return -ENOTSUPP;
106 	if (version)
107 		*version = ret.value;
108 	return 0;
109 }
110 
111 /**
112  * sbi_probe_extension() - Check if an SBI extension ID is supported or not.
113  * @extid: The extension ID to be probed.
114  *
115  * Return: Extension specific nonzero value f yes, -ENOTSUPP otherwise.
116  */
sbi_probe_extension(int extid)117 int sbi_probe_extension(int extid)
118 {
119 	struct sbiret ret;
120 
121 	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_PROBE_EXT, extid,
122 			0, 0, 0, 0, 0);
123 	if (!ret.error)
124 		if (ret.value)
125 			return ret.value;
126 
127 	return -ENOTSUPP;
128 }
129 
130 /**
131  * sbi_get_mvendorid() - get machine vendor ID
132  *
133  * @mimpid:	on return machine vendor ID
134  * Return:	0 on success
135  */
sbi_get_mvendorid(long * mvendorid)136 int sbi_get_mvendorid(long *mvendorid)
137 {
138 	struct sbiret ret;
139 
140 	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_MVENDORID,
141 			0, 0, 0, 0, 0, 0);
142 	if (ret.error)
143 		return -ENOTSUPP;
144 
145 	if (mvendorid)
146 		*mvendorid = ret.value;
147 
148 	return 0;
149 }
150 
151 /**
152  * sbi_get_marchid() - get machine architecture ID
153  *
154  * @mimpid:	on return machine architecture ID
155  * Return:	0 on success
156  */
sbi_get_marchid(long * marchid)157 int sbi_get_marchid(long *marchid)
158 {
159 	struct sbiret ret;
160 
161 	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_MARCHID,
162 			0, 0, 0, 0, 0, 0);
163 
164 	if (ret.error)
165 		return -ENOTSUPP;
166 
167 	if (marchid)
168 		*marchid = ret.value;
169 
170 	return 0;
171 }
172 
173 /**
174  * sbi_get_mimpid() - get machine implementation ID
175  *
176  * @mimpid:	on return machine implementation ID
177  * Return:	0 on success
178  */
sbi_get_mimpid(long * mimpid)179 int sbi_get_mimpid(long *mimpid)
180 {
181 	struct sbiret ret;
182 
183 	ret = sbi_ecall(SBI_EXT_BASE, SBI_EXT_BASE_GET_MIMPID,
184 			0, 0, 0, 0, 0, 0);
185 
186 	if (ret.error)
187 		return -ENOTSUPP;
188 
189 	if (mimpid)
190 		*mimpid = ret.value;
191 
192 	return 0;
193 }
194 
195 /**
196  * sbi_srst_reset() - invoke system reset extension
197  *
198  * @type:	type of reset
199  * @reason:	reason for reset
200  */
sbi_srst_reset(unsigned long type,unsigned long reason)201 void sbi_srst_reset(unsigned long type, unsigned long reason)
202 {
203 	sbi_ecall(SBI_EXT_SRST, SBI_EXT_SRST_RESET, type, reason,
204 		  0, 0, 0, 0);
205 }
206 
207 /**
208  * sbi_dbcn_write_byte() - write byte to debug console
209  *
210  * @ch:		byte to be written
211  * Return:	SBI error code (SBI_SUCCESS = 0 on success)
212  */
sbi_dbcn_write_byte(unsigned char ch)213 int sbi_dbcn_write_byte(unsigned char ch)
214 {
215 	struct sbiret ret;
216 
217 	ret = sbi_ecall(SBI_EXT_DBCN,
218 			SBI_EXT_DBCN_CONSOLE_WRITE_BYTE,
219 			ch, 0, 0, 0, 0, 0);
220 	return ret.error;
221 }
222 
223 #ifdef CONFIG_SBI_V01
224 
225 /**
226  * sbi_console_putchar() - Writes given character to the console device.
227  * @ch: The data to be written to the console.
228  *
229  * Return: None
230  */
sbi_console_putchar(int ch)231 void sbi_console_putchar(int ch)
232 {
233 	sbi_ecall(SBI_EXT_0_1_CONSOLE_PUTCHAR, 0, ch, 0, 0, 0, 0, 0);
234 }
235 
236 /**
237  * sbi_console_getchar() - Reads a byte from console device.
238  *
239  * Returns the value read from console.
240  */
sbi_console_getchar(void)241 int sbi_console_getchar(void)
242 {
243 	struct sbiret ret;
244 
245 	ret = sbi_ecall(SBI_EXT_0_1_CONSOLE_GETCHAR, 0, 0, 0, 0, 0, 0, 0);
246 
247 	return ret.error;
248 }
249 
250 /**
251  * sbi_clear_ipi() - Clear any pending IPIs for the calling hart.
252  *
253  * Return: None
254  */
sbi_clear_ipi(void)255 void sbi_clear_ipi(void)
256 {
257 	sbi_ecall(SBI_EXT_0_1_CLEAR_IPI, 0, 0, 0, 0, 0, 0, 0);
258 }
259 
260 /**
261  * sbi_shutdown() - Remove all the harts from executing supervisor code.
262  *
263  * Return: None
264  */
sbi_shutdown(void)265 void sbi_shutdown(void)
266 {
267 	sbi_ecall(SBI_EXT_0_1_SHUTDOWN, 0, 0, 0, 0, 0, 0, 0);
268 }
269 
270 /**
271  * sbi_send_ipi() - Send an IPI to any hart.
272  * @hart_mask: A cpu mask containing all the target harts.
273  *
274  * Return: None
275  */
sbi_send_ipi(const unsigned long * hart_mask)276 void sbi_send_ipi(const unsigned long *hart_mask)
277 {
278 	sbi_ecall(SBI_EXT_SEND_IPI, SBI_FID_SEND_IPI, (unsigned long)hart_mask,
279 		  0, 0, 0, 0, 0);
280 }
281 
282 /**
283  * sbi_remote_fence_i() - Execute FENCE.I instruction on given remote harts.
284  * @hart_mask: A cpu mask containing all the target harts.
285  *
286  * Return: None
287  */
sbi_remote_fence_i(const unsigned long * hart_mask)288 void sbi_remote_fence_i(const unsigned long *hart_mask)
289 {
290 	sbi_ecall(SBI_EXT_REMOTE_FENCE_I, SBI_FID_REMOTE_FENCE_I,
291 		  (unsigned long)hart_mask, 0, 0, 0, 0, 0);
292 }
293 
294 /**
295  * sbi_remote_sfence_vma() - Execute SFENCE.VMA instructions on given remote
296  *			     harts for the specified virtual address range.
297  * @hart_mask: A cpu mask containing all the target harts.
298  * @start: Start of the virtual address
299  * @size: Total size of the virtual address range.
300  *
301  * Return: None
302  */
sbi_remote_sfence_vma(const unsigned long * hart_mask,unsigned long start,unsigned long size)303 void sbi_remote_sfence_vma(const unsigned long *hart_mask,
304 			   unsigned long start,
305 			   unsigned long size)
306 {
307 	sbi_ecall(SBI_EXT_REMOTE_SFENCE_VMA, SBI_FID_REMOTE_SFENCE_VMA,
308 		  (unsigned long)hart_mask, start, size, 0, 0, 0);
309 }
310 
311 /**
312  * sbi_remote_sfence_vma_asid() - Execute SFENCE.VMA instructions on given
313  * remote harts for a virtual address range belonging to a specific ASID.
314  *
315  * @hart_mask: A cpu mask containing all the target harts.
316  * @start: Start of the virtual address
317  * @size: Total size of the virtual address range.
318  * @asid: The value of address space identifier (ASID).
319  *
320  * Return: None
321  */
sbi_remote_sfence_vma_asid(const unsigned long * hart_mask,unsigned long start,unsigned long size,unsigned long asid)322 void sbi_remote_sfence_vma_asid(const unsigned long *hart_mask,
323 				unsigned long start,
324 				unsigned long size,
325 				unsigned long asid)
326 {
327 	sbi_ecall(SBI_EXT_REMOTE_SFENCE_VMA_ASID,
328 		  SBI_FID_REMOTE_SFENCE_VMA_ASID,
329 		  (unsigned long)hart_mask, start, size, asid, 0, 0);
330 }
331 
332 #endif /* CONFIG_SBI_V01 */
333