1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * This file contains the generic code to perform a call to the
4 * pSeries LPAR hypervisor.
5 */
6#include <linux/jump_label.h>
7#include <asm/hvcall.h>
8#include <asm/processor.h>
9#include <asm/ppc_asm.h>
10#include <asm/asm-offsets.h>
11#include <asm/ptrace.h>
12#include <asm/feature-fixups.h>
13
14	.section	".text"
15
16#ifdef CONFIG_TRACEPOINTS
17
18#ifndef CONFIG_JUMP_LABEL
19	.data
20
21	.globl hcall_tracepoint_refcount
22hcall_tracepoint_refcount:
23	.8byte	0
24
25	.section	".text"
26#endif
27
28/*
29 * precall must preserve all registers.  use unused STK_PARAM()
30 * areas to save snapshots and opcode. STK_PARAM() in the caller's
31 * frame will be available even on ELFv2 because these are all
32 * variadic functions.
33 */
34#define HCALL_INST_PRECALL(FIRST_REG)				\
35	mflr	r0;						\
36	std	r3,STK_PARAM(R3)(r1);				\
37	std	r4,STK_PARAM(R4)(r1);				\
38	std	r5,STK_PARAM(R5)(r1);				\
39	std	r6,STK_PARAM(R6)(r1);				\
40	std	r7,STK_PARAM(R7)(r1);				\
41	std	r8,STK_PARAM(R8)(r1);				\
42	std	r9,STK_PARAM(R9)(r1);				\
43	std	r10,STK_PARAM(R10)(r1);				\
44	std	r0,16(r1);					\
45	addi	r4,r1,STK_PARAM(FIRST_REG);			\
46	stdu	r1,-STACK_FRAME_MIN_SIZE(r1);			\
47	bl	CFUNC(__trace_hcall_entry);			\
48	ld	r3,STACK_FRAME_MIN_SIZE+STK_PARAM(R3)(r1);	\
49	ld	r4,STACK_FRAME_MIN_SIZE+STK_PARAM(R4)(r1);	\
50	ld	r5,STACK_FRAME_MIN_SIZE+STK_PARAM(R5)(r1);	\
51	ld	r6,STACK_FRAME_MIN_SIZE+STK_PARAM(R6)(r1);	\
52	ld	r7,STACK_FRAME_MIN_SIZE+STK_PARAM(R7)(r1);	\
53	ld	r8,STACK_FRAME_MIN_SIZE+STK_PARAM(R8)(r1);	\
54	ld	r9,STACK_FRAME_MIN_SIZE+STK_PARAM(R9)(r1);	\
55	ld	r10,STACK_FRAME_MIN_SIZE+STK_PARAM(R10)(r1)
56
57/*
58 * postcall is performed immediately before function return which
59 * allows liberal use of volatile registers.
60 */
61#define __HCALL_INST_POSTCALL					\
62	ld	r0,STACK_FRAME_MIN_SIZE+STK_PARAM(R3)(r1);	\
63	std	r3,STACK_FRAME_MIN_SIZE+STK_PARAM(R3)(r1);	\
64	mr	r4,r3;						\
65	mr	r3,r0;						\
66	bl	CFUNC(__trace_hcall_exit);			\
67	ld	r0,STACK_FRAME_MIN_SIZE+16(r1);			\
68	addi	r1,r1,STACK_FRAME_MIN_SIZE;			\
69	ld	r3,STK_PARAM(R3)(r1);				\
70	mtlr	r0
71
72#define HCALL_INST_POSTCALL_NORETS				\
73	li	r5,0;						\
74	__HCALL_INST_POSTCALL
75
76#define HCALL_INST_POSTCALL(BUFREG)				\
77	mr	r5,BUFREG;					\
78	__HCALL_INST_POSTCALL
79
80#ifdef CONFIG_JUMP_LABEL
81#define HCALL_BRANCH(LABEL)					\
82	ARCH_STATIC_BRANCH(LABEL, hcall_tracepoint_key)
83#else
84
85/*
86 * We branch around this in early init (eg when populating the MMU
87 * hashtable) by using an unconditional cpu feature.
88 */
89#define HCALL_BRANCH(LABEL)					\
90BEGIN_FTR_SECTION;						\
91	b	1f;						\
92END_FTR_SECTION(0, 1);						\
93	LOAD_REG_ADDR(r12, hcall_tracepoint_refcount) ;		\
94	std	r12,32(r1);					\
95	cmpdi	r12,0;						\
96	bne-	LABEL;						\
971:
98#endif
99
100#else
101#define HCALL_INST_PRECALL(FIRST_ARG)
102#define HCALL_INST_POSTCALL_NORETS
103#define HCALL_INST_POSTCALL(BUFREG)
104#define HCALL_BRANCH(LABEL)
105#endif
106
107_GLOBAL_TOC(plpar_hcall_norets_notrace)
108	HMT_MEDIUM
109
110	mfcr	r0
111	stw	r0,8(r1)
112	HVSC				/* invoke the hypervisor */
113
114	li	r4,0
115	stb	r4,PACASRR_VALID(r13)
116
117	lwz	r0,8(r1)
118	mtcrf	0xff,r0
119	blr				/* return r3 = status */
120
121_GLOBAL_TOC(plpar_hcall_norets)
122	HMT_MEDIUM
123
124	mfcr	r0
125	stw	r0,8(r1)
126	HCALL_BRANCH(plpar_hcall_norets_trace)
127	HVSC				/* invoke the hypervisor */
128
129	li	r4,0
130	stb	r4,PACASRR_VALID(r13)
131
132	lwz	r0,8(r1)
133	mtcrf	0xff,r0
134	blr				/* return r3 = status */
135
136#ifdef CONFIG_TRACEPOINTS
137plpar_hcall_norets_trace:
138	HCALL_INST_PRECALL(R4)
139	HVSC
140	HCALL_INST_POSTCALL_NORETS
141
142	li	r4,0
143	stb	r4,PACASRR_VALID(r13)
144
145	lwz	r0,8(r1)
146	mtcrf	0xff,r0
147	blr
148#endif
149
150_GLOBAL_TOC(plpar_hcall)
151	HMT_MEDIUM
152
153	mfcr	r0
154	stw	r0,8(r1)
155
156	HCALL_BRANCH(plpar_hcall_trace)
157
158	std     r4,STK_PARAM(R4)(r1)     /* Save ret buffer */
159
160	mr	r4,r5
161	mr	r5,r6
162	mr	r6,r7
163	mr	r7,r8
164	mr	r8,r9
165	mr	r9,r10
166
167	HVSC				/* invoke the hypervisor */
168
169	ld	r12,STK_PARAM(R4)(r1)
170	std	r4,  0(r12)
171	std	r5,  8(r12)
172	std	r6, 16(r12)
173	std	r7, 24(r12)
174
175	li	r4,0
176	stb	r4,PACASRR_VALID(r13)
177
178	lwz	r0,8(r1)
179	mtcrf	0xff,r0
180
181	blr				/* return r3 = status */
182
183#ifdef CONFIG_TRACEPOINTS
184plpar_hcall_trace:
185	HCALL_INST_PRECALL(R5)
186
187	std	r4,STK_PARAM(R4)(r1)
188	mr	r0,r4
189
190	mr	r4,r5
191	mr	r5,r6
192	mr	r6,r7
193	mr	r7,r8
194	mr	r8,r9
195	mr	r9,r10
196
197	HVSC
198
199	ld	r12,STK_PARAM(R4)(r1)
200	std	r4,0(r12)
201	std	r5,8(r12)
202	std	r6,16(r12)
203	std	r7,24(r12)
204
205	HCALL_INST_POSTCALL(r12)
206
207	li	r4,0
208	stb	r4,PACASRR_VALID(r13)
209
210	lwz	r0,8(r1)
211	mtcrf	0xff,r0
212
213	blr
214#endif
215
216/*
217 * plpar_hcall_raw can be called in real mode. kexec/kdump need some
218 * hypervisor calls to be executed in real mode. So plpar_hcall_raw
219 * does not access the per cpu hypervisor call statistics variables,
220 * since these variables may not be present in the RMO region.
221 */
222_GLOBAL(plpar_hcall_raw)
223	HMT_MEDIUM
224
225	mfcr	r0
226	stw	r0,8(r1)
227
228	std     r4,STK_PARAM(R4)(r1)     /* Save ret buffer */
229
230	mr	r4,r5
231	mr	r5,r6
232	mr	r6,r7
233	mr	r7,r8
234	mr	r8,r9
235	mr	r9,r10
236
237	HVSC				/* invoke the hypervisor */
238
239	ld	r12,STK_PARAM(R4)(r1)
240	std	r4,  0(r12)
241	std	r5,  8(r12)
242	std	r6, 16(r12)
243	std	r7, 24(r12)
244
245	li	r4,0
246	stb	r4,PACASRR_VALID(r13)
247
248	lwz	r0,8(r1)
249	mtcrf	0xff,r0
250
251	blr				/* return r3 = status */
252
253_GLOBAL_TOC(plpar_hcall9)
254	HMT_MEDIUM
255
256	mfcr	r0
257	stw	r0,8(r1)
258
259	HCALL_BRANCH(plpar_hcall9_trace)
260
261	std     r4,STK_PARAM(R4)(r1)     /* Save ret buffer */
262
263	mr	r4,r5
264	mr	r5,r6
265	mr	r6,r7
266	mr	r7,r8
267	mr	r8,r9
268	mr	r9,r10
269	ld	r10,STK_PARAM(R11)(r1)	 /* put arg7 in R10 */
270	ld	r11,STK_PARAM(R12)(r1)	 /* put arg8 in R11 */
271	ld	r12,STK_PARAM(R13)(r1)    /* put arg9 in R12 */
272
273	HVSC				/* invoke the hypervisor */
274
275	mr	r0,r12
276	ld	r12,STK_PARAM(R4)(r1)
277	std	r4,  0(r12)
278	std	r5,  8(r12)
279	std	r6, 16(r12)
280	std	r7, 24(r12)
281	std	r8, 32(r12)
282	std	r9, 40(r12)
283	std	r10,48(r12)
284	std	r11,56(r12)
285	std	r0, 64(r12)
286
287	li	r4,0
288	stb	r4,PACASRR_VALID(r13)
289
290	lwz	r0,8(r1)
291	mtcrf	0xff,r0
292
293	blr				/* return r3 = status */
294
295#ifdef CONFIG_TRACEPOINTS
296plpar_hcall9_trace:
297	HCALL_INST_PRECALL(R5)
298
299	std	r4,STK_PARAM(R4)(r1)
300	mr	r0,r4
301
302	mr	r4,r5
303	mr	r5,r6
304	mr	r6,r7
305	mr	r7,r8
306	mr	r8,r9
307	mr	r9,r10
308	ld	r10,STACK_FRAME_MIN_SIZE+STK_PARAM(R11)(r1)
309	ld	r11,STACK_FRAME_MIN_SIZE+STK_PARAM(R12)(r1)
310	ld	r12,STACK_FRAME_MIN_SIZE+STK_PARAM(R13)(r1)
311
312	HVSC
313
314	mr	r0,r12
315	ld	r12,STACK_FRAME_MIN_SIZE+STK_PARAM(R4)(r1)
316	std	r4,0(r12)
317	std	r5,8(r12)
318	std	r6,16(r12)
319	std	r7,24(r12)
320	std	r8,32(r12)
321	std	r9,40(r12)
322	std	r10,48(r12)
323	std	r11,56(r12)
324	std	r0,64(r12)
325
326	HCALL_INST_POSTCALL(r12)
327
328	li	r4,0
329	stb	r4,PACASRR_VALID(r13)
330
331	lwz	r0,8(r1)
332	mtcrf	0xff,r0
333
334	blr
335#endif
336
337/* See plpar_hcall_raw to see why this is needed */
338_GLOBAL(plpar_hcall9_raw)
339	HMT_MEDIUM
340
341	mfcr	r0
342	stw	r0,8(r1)
343
344	std     r4,STK_PARAM(R4)(r1)     /* Save ret buffer */
345
346	mr	r4,r5
347	mr	r5,r6
348	mr	r6,r7
349	mr	r7,r8
350	mr	r8,r9
351	mr	r9,r10
352	ld	r10,STK_PARAM(R11)(r1)	 /* put arg7 in R10 */
353	ld	r11,STK_PARAM(R12)(r1)	 /* put arg8 in R11 */
354	ld	r12,STK_PARAM(R13)(r1)    /* put arg9 in R12 */
355
356	HVSC				/* invoke the hypervisor */
357
358	mr	r0,r12
359	ld	r12,STK_PARAM(R4)(r1)
360	std	r4,  0(r12)
361	std	r5,  8(r12)
362	std	r6, 16(r12)
363	std	r7, 24(r12)
364	std	r8, 32(r12)
365	std	r9, 40(r12)
366	std	r10,48(r12)
367	std	r11,56(r12)
368	std	r0, 64(r12)
369
370	li	r4,0
371	stb	r4,PACASRR_VALID(r13)
372
373	lwz	r0,8(r1)
374	mtcrf	0xff,r0
375
376	blr				/* return r3 = status */
377