1/*
2 *
3 * This file is subject to the terms and conditions of the GNU General Public
4 * License.  See the file "COPYING" in the main directory of this archive
5 * for more details.
6 *
7 * Copyright (C) 2000 Hewlett Packard (Paul Bame bame@puffin.external.hp.com)
8 *
9 */
10#include <asm/assembly.h>
11#include <asm/psw.h>
12
13	.section	.bss
14	.export real_stack
15	.align	64
16real_stack:
17	.block	8192
18
19#ifdef __LP64__
20#  define REG_SZ 8
21#else
22#  define REG_SZ 4
23#endif
24
25#define N_SAVED_REGS 9
26
27save_cr_space:
28	.block	REG_SZ * N_SAVED_REGS
29
30
31/************************ 32-bit real-mode calls ***********************/
32/* This can be called in both narrow and wide kernels */
33
34	.text
35
36	.export real32_call_asm
37
38	/* unsigned long real32_call_asm(unsigned int *sp,
39	 *		unsigned int *arg0p,
40	 *		unsigned int iodc_fn)
41	 *	sp is value of stack pointer to adopt before calling PDC (virt)
42	 *	arg0p points to where saved arg values may be found
43	 *	iodc_fn is the IODC function to call
44	 */
45
46real32_call_asm:
47	STREG	%rp, -RP_OFFSET(%sp)	/* save RP */
48#ifdef __LP64__
49	callee_save
50	ldo	2*REG_SZ(%sp), %sp	/* room for a couple more saves */
51	STREG	%r27, -1*REG_SZ(%sp)
52	STREG	%r29, -2*REG_SZ(%sp)
53#endif
54	STREG	%sp, -REG_SZ(%arg0)	/* save SP on real-mode stack */
55	copy	%arg0, %sp		/* adopt the real-mode SP */
56
57	/* save iodc_fn */
58	copy	%arg2, %r31
59
60	/* load up the arg registers from the saved arg area */
61	/* 32-bit calling convention passes first 4 args in registers */
62	ldw	0(%arg1), %arg0		/* note overwriting arg0 */
63	ldw	-8(%arg1), %arg2
64	ldw	-12(%arg1), %arg3
65	ldw	-4(%arg1), %arg1	/* obviously must do this one last! */
66
67	tophys_r1  %sp
68
69	b,l	rfi_virt2real,%r2
70	nop
71
72	b,l	save_control_regs,%r2		/* modifies r1, r2, r28 */
73	nop
74
75#ifdef __LP64__
76	rsm	PSW_SM_W, %r0		/* go narrow */
77#endif
78
79	ldil	L%PA(ric_ret), %r2
80	ldo	R%PA(ric_ret)(%r2), %r2
81	bv	0(%r31)
82	nop
83ric_ret:
84#ifdef __LP64__
85	ssm	PSW_SM_W, %r0		/* go wide */
86#endif
87	/* restore CRs before going virtual in case we page fault */
88	b,l	restore_control_regs, %r2	/* modifies r1, r2, r26 */
89	nop
90
91	b,l	rfi_real2virt,%r2
92	nop
93
94	tovirt_r1 %sp
95	LDREG	-REG_SZ(%sp), %sp	/* restore SP */
96#ifdef __LP64__
97	LDREG	-1*REG_SZ(%sp), %r27
98	LDREG	-2*REG_SZ(%sp), %r29
99	ldo	-2*REG_SZ(%sp), %sp
100	callee_rest
101#endif
102	LDREG	-RP_OFFSET(%sp), %rp	/* restore RP */
103	bv	0(%rp)
104	nop
105
106
107#  define PUSH_CR(r, where) mfctl r, %r1 ! STREG,ma %r1, REG_SZ(where)
108#  define POP_CR(r, where) LDREG,mb -REG_SZ(where), %r1 ! mtctl %r1, r
109
110	.text
111save_control_regs:
112	load32	PA(save_cr_space), %r28
113	PUSH_CR(%cr24, %r28)
114	PUSH_CR(%cr25, %r28)
115	PUSH_CR(%cr26, %r28)
116	PUSH_CR(%cr27, %r28)
117	PUSH_CR(%cr28, %r28)
118	PUSH_CR(%cr29, %r28)
119	PUSH_CR(%cr30, %r28)
120	PUSH_CR(%cr31, %r28)
121	PUSH_CR(%cr15, %r28)
122	bv 0(%r2)
123	nop
124
125restore_control_regs:
126	load32	PA(save_cr_space + (N_SAVED_REGS * REG_SZ)), %r26
127	POP_CR(%cr15, %r26)
128	POP_CR(%cr31, %r26)
129	POP_CR(%cr30, %r26)
130	POP_CR(%cr29, %r26)
131	POP_CR(%cr28, %r26)
132	POP_CR(%cr27, %r26)
133	POP_CR(%cr26, %r26)
134	POP_CR(%cr25, %r26)
135	POP_CR(%cr24, %r26)
136	bv 0(%r2)
137	nop
138
139/* rfi_virt2real() and rfi_real2virt() could perhaps be adapted for
140 * more general-purpose use by the several places which need RFIs
141 */
142	.align 128
143	.text
144rfi_virt2real:
145	/* switch to real mode... */
146	ssm		0,0		/* See "relied upon translation" */
147	nop				/* comment in interruption.S */
148	nop
149	nop
150	nop
151	nop
152	nop
153	nop
154	nop
155
156	rsm             (PSW_SM_Q|PSW_SM_I),%r0  /* disable Q & I bits to load iia queue */
157	mtctl		0, %cr17	/* space 0 */
158	mtctl		0, %cr17
159	load32		PA(rfi_v2r_1), %r1
160	mtctl		%r1, %cr18
161	ldo		4(%r1), %r1
162	mtctl		%r1, %cr18
163	load32          REAL_MODE_PSW, %r1
164	mtctl		%r1, %cr22
165	rfi
166
167	nop
168	nop
169	nop
170	nop
171	nop
172	nop
173	nop
174	nop
175rfi_v2r_1:
176	tophys_r1 %r2
177	bv	0(%r2)
178	nop
179
180	.text
181	.align 128
182rfi_real2virt:
183	ssm		0,0		/* See "relied upon translation" */
184	nop				/* comment in interruption.S */
185	nop
186	nop
187	nop
188	nop
189	nop
190	nop
191	nop
192
193	rsm             PSW_SM_Q,%r0    /* disable Q bit to load iia queue */
194	mtctl		0, %cr17	/* space 0 */
195	mtctl		0, %cr17
196	load32		(rfi_r2v_1), %r1
197	mtctl		%r1, %cr18
198	ldo		4(%r1), %r1
199	mtctl		%r1, %cr18
200	load32		KERNEL_PSW, %r1
201	mtctl		%r1, %cr22
202	rfi
203
204	nop
205	nop
206	nop
207	nop
208	nop
209	nop
210	nop
211	nop
212rfi_r2v_1:
213	tovirt_r1 %r2
214	bv	0(%r2)
215	nop
216
217#ifdef __LP64__
218
219/************************ 64-bit real-mode calls ***********************/
220/* This is only usable in wide kernels right now and will probably stay so */
221	.text
222	.export real64_call_asm
223	/* unsigned long real64_call_asm(unsigned long *sp,
224	 *		unsigned long *arg0p,
225	 *		unsigned long fn)
226	 *	sp is value of stack pointer to adopt before calling PDC (virt)
227	 *	arg0p points to where saved arg values may be found
228	 *	iodc_fn is the IODC function to call
229	 */
230real64_call_asm:
231	std	%rp, -0x10(%sp)		/* save RP */
232	std	%sp, -8(%arg0)		/* save SP on real-mode stack */
233	copy	%arg0, %sp		/* adopt the real-mode SP */
234
235	/* save fn */
236	copy	%arg2, %r31
237
238	/* set up the new ap */
239	ldo	64(%arg1), %r29
240
241	/* load up the arg registers from the saved arg area */
242	/* 32-bit calling convention passes first 4 args in registers */
243	ldd	0*REG_SZ(%arg1), %arg0		/* note overwriting arg0 */
244	ldd	2*REG_SZ(%arg1), %arg2
245	ldd	3*REG_SZ(%arg1), %arg3
246	ldd	4*REG_SZ(%arg1), %r22
247	ldd	5*REG_SZ(%arg1), %r21
248	ldd	6*REG_SZ(%arg1), %r20
249	ldd	7*REG_SZ(%arg1), %r19
250	ldd	1*REG_SZ(%arg1), %arg1		/* do this one last! */
251
252	tophys_r1 %sp
253
254	b,l	rfi_virt2real,%r2
255	nop
256
257	b,l	save_control_regs,%r2		/* modifies r1, r2, r28 */
258	nop
259
260	load32	PA(r64_ret), %r2
261	bv	0(%r31)
262	nop
263r64_ret:
264	/* restore CRs before going virtual in case we page fault */
265	b,l	restore_control_regs, %r2	/* modifies r1, r2, r26 */
266	nop
267
268	b,l	rfi_real2virt,%r2
269	nop
270
271	tovirt_r1 %sp
272	ldd	-8(%sp), %sp		/* restore SP */
273	ldd	-0x10(%sp), %rp		/* restore RP */
274	bv	0(%rp)
275	nop
276
277#endif
278	.export pc_in_user_space
279	.text
280	/* Doesn't belong here but I couldn't find a nicer spot. */
281	/* Should never get called, only used by profile stuff in time.c */
282pc_in_user_space:
283	bv,n	0(%rp)
284	nop
285
286