[mirror_ubuntu-bionic-kernel.git] / arch / parisc / kernel / real2.S

/*
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2000 Hewlett Packard (Paul Bame bame@puffin.external.hp.com)
 *
 */
#include <asm/psw.h>
#include <asm/assembly.h>

	.section	.bss
	.export real_stack
	.export real32_stack
	.export real64_stack
	.align	64
real_stack:
real32_stack:
real64_stack:
	.block	8192

#ifdef __LP64__
#  define REG_SZ 8
#else
#  define REG_SZ 4
#endif

#define N_SAVED_REGS 9

save_cr_space:
	.block	REG_SZ * N_SAVED_REGS
save_cr_end:


/************************ 32-bit real-mode calls ***********************/
/* This can be called in both narrow and wide kernels */

	.text

	.export real32_call_asm

	/* unsigned long real32_call_asm(unsigned int *sp,
	 *		unsigned int *arg0p,
	 *		unsigned int iodc_fn)
	 *	sp is value of stack pointer to adopt before calling PDC (virt)
	 *	arg0p points to where saved arg values may be found
	 *	iodc_fn is the IODC function to call
	 */

real32_call_asm:
	STREG	%rp, -RP_OFFSET(%sp)	/* save RP */
#ifdef __LP64__
	callee_save
	ldo	2*REG_SZ(%sp), %sp	/* room for a couple more saves */
	STREG	%r27, -1*REG_SZ(%sp)
	STREG	%r29, -2*REG_SZ(%sp)
#endif
	STREG	%sp, -REG_SZ(%arg0)	/* save SP on real-mode stack */
	copy	%arg0, %sp		/* adopt the real-mode SP */

	/* save iodc_fn */
	copy	%arg2, %r31

	/* load up the arg registers from the saved arg area */
	/* 32-bit calling convention passes first 4 args in registers */
	ldw	0(%arg1), %arg0		/* note overwriting arg0 */
	ldw	-8(%arg1), %arg2
	ldw	-12(%arg1), %arg3
	ldw	-4(%arg1), %arg1	/* obviously must do this one last! */

	tophys_r1  %sp

	b,l	rfi_virt2real,%r2
	nop

	b,l	save_control_regs,%r2		/* modifies r1, r2, r28 */
	nop

#ifdef __LP64__
	rsm	PSW_SM_W, %r0		/* go narrow */
#endif

	load32	PA(ric_ret), %r2
	bv	0(%r31)
	nop
ric_ret:
#ifdef __LP64__
	ssm	PSW_SM_W, %r0		/* go wide */
#endif
	/* restore CRs before going virtual in case we page fault */
	b,l	restore_control_regs, %r2	/* modifies r1, r2, r26 */
	nop

	b,l	rfi_real2virt,%r2
	nop

	tovirt_r1 %sp
	LDREG	-REG_SZ(%sp), %sp	/* restore SP */
#ifdef __LP64__
	LDREG	-1*REG_SZ(%sp), %r27
	LDREG	-2*REG_SZ(%sp), %r29
	ldo	-2*REG_SZ(%sp), %sp
	callee_rest
#endif
	LDREG	-RP_OFFSET(%sp), %rp	/* restore RP */
	bv	0(%rp)
	nop


#  define PUSH_CR(r, where) mfctl r, %r1 ! STREG,ma %r1, REG_SZ(where)
#  define POP_CR(r, where) LDREG,mb -REG_SZ(where), %r1 ! mtctl %r1, r

	.text
save_control_regs:
	load32	PA(save_cr_space), %r28
	PUSH_CR(%cr24, %r28)
	PUSH_CR(%cr25, %r28)
	PUSH_CR(%cr26, %r28)
	PUSH_CR(%cr27, %r28)
	PUSH_CR(%cr28, %r28)
	PUSH_CR(%cr29, %r28)
	PUSH_CR(%cr30, %r28)
	PUSH_CR(%cr31, %r28)
	PUSH_CR(%cr15, %r28)
	bv 0(%r2)
	nop

restore_control_regs:
	load32	PA(save_cr_end), %r26
	POP_CR(%cr15, %r26)
	POP_CR(%cr31, %r26)
	POP_CR(%cr30, %r26)
	POP_CR(%cr29, %r26)
	POP_CR(%cr28, %r26)
	POP_CR(%cr27, %r26)
	POP_CR(%cr26, %r26)
	POP_CR(%cr25, %r26)
	POP_CR(%cr24, %r26)
	bv 0(%r2)
	nop

/* rfi_virt2real() and rfi_real2virt() could perhaps be adapted for
 * more general-purpose use by the several places which need RFIs
 */
	.align 128
	.text
rfi_virt2real:
	/* switch to real mode... */
	rsm		PSW_SM_I,%r0
	load32		PA(rfi_v2r_1), %r1
	nop
	nop
	nop
	nop
	nop
	
	rsm             PSW_SM_Q,%r0  /* disable Q & I bits to load iia queue */
	mtctl		%r0, %cr17	/* Clear IIASQ tail */
	mtctl		%r0, %cr17	/* Clear IIASQ head */
	mtctl		%r1, %cr18	/* IIAOQ head */
	ldo		4(%r1), %r1
	mtctl		%r1, %cr18	/* IIAOQ tail */
	load32          REAL_MODE_PSW, %r1
	mtctl		%r1, %cr22
	rfi
	
	nop
	nop
	nop
	nop
	nop
	nop
	nop
	nop
rfi_v2r_1:
	tophys_r1 %r2
	bv	0(%r2)
	nop

	.text
	.align 128
rfi_real2virt:
	rsm		PSW_SM_I,%r0
	load32		(rfi_r2v_1), %r1
	nop
	nop
	nop
	nop
	nop
	
	rsm             PSW_SM_Q,%r0    /* disable Q bit to load iia queue */
	mtctl		%r0, %cr17	/* Clear IIASQ tail */
	mtctl		%r0, %cr17	/* Clear IIASQ head */
	mtctl		%r1, %cr18	/* IIAOQ head */
	ldo		4(%r1), %r1
	mtctl		%r1, %cr18	/* IIAOQ tail */
	load32		KERNEL_PSW, %r1
	mtctl		%r1, %cr22
	rfi
	
	nop
	nop
	nop
	nop
	nop
	nop
	nop
	nop
rfi_r2v_1:
	tovirt_r1 %r2
	bv	0(%r2)
	nop

#ifdef __LP64__

/************************ 64-bit real-mode calls ***********************/
/* This is only usable in wide kernels right now and will probably stay so */
	.text
	.export real64_call_asm
	/* unsigned long real64_call_asm(unsigned long *sp,
	 *		unsigned long *arg0p,
	 *		unsigned long fn)
	 *	sp is value of stack pointer to adopt before calling PDC (virt)
	 *	arg0p points to where saved arg values may be found
	 *	iodc_fn is the IODC function to call
	 */
real64_call_asm:
	std	%rp, -0x10(%sp)		/* save RP */
	std	%sp, -8(%arg0)		/* save SP on real-mode stack */
	copy	%arg0, %sp		/* adopt the real-mode SP */

	/* save fn */
	copy	%arg2, %r31

	/* set up the new ap */
	ldo	64(%arg1), %r29

	/* load up the arg registers from the saved arg area */
	/* 32-bit calling convention passes first 4 args in registers */
	ldd	0*REG_SZ(%arg1), %arg0		/* note overwriting arg0 */
	ldd	2*REG_SZ(%arg1), %arg2
	ldd	3*REG_SZ(%arg1), %arg3
	ldd	4*REG_SZ(%arg1), %r22
	ldd	5*REG_SZ(%arg1), %r21
	ldd	6*REG_SZ(%arg1), %r20
	ldd	7*REG_SZ(%arg1), %r19
	ldd	1*REG_SZ(%arg1), %arg1		/* do this one last! */

	tophys_r1 %sp

	b,l	rfi_virt2real,%r2
	nop

	b,l	save_control_regs,%r2		/* modifies r1, r2, r28 */
	nop

	load32	PA(r64_ret), %r2
	bv	0(%r31)
	nop
r64_ret:
	/* restore CRs before going virtual in case we page fault */
	b,l	restore_control_regs, %r2	/* modifies r1, r2, r26 */
	nop

	b,l	rfi_real2virt,%r2
	nop

	tovirt_r1 %sp
	ldd	-8(%sp), %sp		/* restore SP */
	ldd	-0x10(%sp), %rp		/* restore RP */
	bv	0(%rp)
	nop

#endif

	.export pc_in_user_space
	.text
	/* Doesn't belong here but I couldn't find a nicer spot. */
	/* Should never get called, only used by profile stuff in time.c */
pc_in_user_space:
	bv,n	0(%rp)
	nop


	.export __canonicalize_funcptr_for_compare
	.text
	/* http://lists.parisc-linux.org/hypermail/parisc-linux/10916.html
	**	GCC 3.3 and later has a new function in libgcc.a for
	**	comparing function pointers.
	*/
__canonicalize_funcptr_for_compare:
#ifdef __LP64__
	bve (%r2)
#else
	bv %r0(%r2)
#endif
	copy %r26,%r28
Commit	Line	Data
1da177e4 LT	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	*/
1da177e4	10	#include <asm/psw.h>
896a3756	11	#include <asm/assembly.h>
1da177e4 LT	12
	13	.section .bss
	14	.export real_stack
	15	.export real32_stack
	16	.export real64_stack
	17	.align 64
	18	real_stack:
	19	real32_stack:
	20	real64_stack:
	21	.block 8192
	22
	23	#ifdef __LP64__
	24	# define REG_SZ 8
	25	#else
	26	# define REG_SZ 4
	27	#endif
	28
	29	#define N_SAVED_REGS 9
	30
	31	save_cr_space:
	32	.block REG_SZ * N_SAVED_REGS
	33	save_cr_end:
	34
	35
	36	/********************** 32-bit real-mode calls *********************/
	37	/* This can be called in both narrow and wide kernels */
	38
	39	.text
	40
	41	.export real32_call_asm
	42
	43	/* unsigned long real32_call_asm(unsigned int *sp,
	44	* unsigned int *arg0p,
	45	* unsigned int iodc_fn)
	46	* sp is value of stack pointer to adopt before calling PDC (virt)
	47	* arg0p points to where saved arg values may be found
	48	* iodc_fn is the IODC function to call
	49	*/
	50
	51	real32_call_asm:
	52	STREG %rp, -RP_OFFSET(%sp) /* save RP */
	53	#ifdef __LP64__
	54	callee_save
	55	ldo 2REG_SZ(%sp), %sp / room for a couple more saves */
	56	STREG %r27, -1*REG_SZ(%sp)
	57	STREG %r29, -2*REG_SZ(%sp)
	58	#endif
	59	STREG %sp, -REG_SZ(%arg0) /* save SP on real-mode stack */
	60	copy %arg0, %sp /* adopt the real-mode SP */
	61
	62	/* save iodc_fn */
	63	copy %arg2, %r31
	64
	65	/* load up the arg registers from the saved arg area */
	66	/* 32-bit calling convention passes first 4 args in registers */
	67	ldw 0(%arg1), %arg0 /* note overwriting arg0 */
	68	ldw -8(%arg1), %arg2
	69	ldw -12(%arg1), %arg3
	70	ldw -4(%arg1), %arg1 /* obviously must do this one last! */
	71
	72	tophys_r1 %sp
	73
	74	b,l rfi_virt2real,%r2
	75	nop
76
77	b,l save_control_regs,%r2 /* modifies r1, r2, r28 */
78	nop
79
80	#ifdef __LP64__
81	rsm PSW_SM_W, %r0 /* go narrow */
82	#endif
83
84	load32 PA(ric_ret), %r2
85	bv 0(%r31)
86	nop
87	ric_ret:
88	#ifdef __LP64__
89	ssm PSW_SM_W, %r0 /* go wide */
90	#endif
91	/* restore CRs before going virtual in case we page fault */
92	b,l restore_control_regs, %r2 /* modifies r1, r2, r26 */
93	nop
94
95	b,l rfi_real2virt,%r2
96	nop
97
98	tovirt_r1 %sp
99	LDREG -REG_SZ(%sp), %sp /* restore SP */
100	#ifdef __LP64__
101	LDREG -1*REG_SZ(%sp), %r27
102	LDREG -2*REG_SZ(%sp), %r29
103	ldo -2*REG_SZ(%sp), %sp
104	callee_rest
105	#endif
106	LDREG -RP_OFFSET(%sp), %rp /* restore RP */
107	bv 0(%rp)
108	nop
109
110
111	# define PUSH_CR(r, where) mfctl r, %r1 ! STREG,ma %r1, REG_SZ(where)
112	# define POP_CR(r, where) LDREG,mb -REG_SZ(where), %r1 ! mtctl %r1, r
113
114	.text
115	save_control_regs:
116	load32 PA(save_cr_space), %r28
117	PUSH_CR(%cr24, %r28)
118	PUSH_CR(%cr25, %r28)
119	PUSH_CR(%cr26, %r28)
120	PUSH_CR(%cr27, %r28)
121	PUSH_CR(%cr28, %r28)
122	PUSH_CR(%cr29, %r28)
123	PUSH_CR(%cr30, %r28)
124	PUSH_CR(%cr31, %r28)
125	PUSH_CR(%cr15, %r28)
126	bv 0(%r2)
127	nop
128
129	restore_control_regs:
130	load32 PA(save_cr_end), %r26
131	POP_CR(%cr15, %r26)
132	POP_CR(%cr31, %r26)
133	POP_CR(%cr30, %r26)
134	POP_CR(%cr29, %r26)
135	POP_CR(%cr28, %r26)
136	POP_CR(%cr27, %r26)
137	POP_CR(%cr26, %r26)
138	POP_CR(%cr25, %r26)
139	POP_CR(%cr24, %r26)
140	bv 0(%r2)
141	nop
142
143	/* rfi_virt2real() and rfi_real2virt() could perhaps be adapted for
144	* more general-purpose use by the several places which need RFIs
145	*/
146	.align 128
147	.text
148	rfi_virt2real:
149	/* switch to real mode... */
896a3756 GG	150	rsm PSW_SM_I,%r0
896a3756 GG	151	load32 PA(rfi_v2r_1), %r1
1da177e4 LT	152	nop
	153	nop
	154	nop
	155	nop
	156	nop
	157
896a3756	158	rsm PSW_SM_Q,%r0 /* disable Q & I bits to load iia queue */
1da177e4 LT	159	mtctl %r0, %cr17 /* Clear IIASQ tail */
1da177e4 LT	160	mtctl %r0, %cr17 /* Clear IIASQ head */
1da177e4 LT	161	mtctl %r1, %cr18 /* IIAOQ head */
	162	ldo 4(%r1), %r1
	163	mtctl %r1, %cr18 /* IIAOQ tail */
	164	load32 REAL_MODE_PSW, %r1
	165	mtctl %r1, %cr22
	166	rfi
	167
	168	nop
	169	nop
	170	nop
	171	nop
	172	nop
	173	nop
	174	nop
	175	nop
	176	rfi_v2r_1:
	177	tophys_r1 %r2
	178	bv 0(%r2)
	179	nop
	180
	181	.text
	182	.align 128
	183	rfi_real2virt:
896a3756 GG	184	rsm PSW_SM_I,%r0
896a3756 GG	185	load32 (rfi_r2v_1), %r1
1da177e4 LT	186	nop
	187	nop
	188	nop
	189	nop
	190	nop
	191
	192	rsm PSW_SM_Q,%r0 /* disable Q bit to load iia queue */
	193	mtctl %r0, %cr17 /* Clear IIASQ tail */
	194	mtctl %r0, %cr17 /* Clear IIASQ head */
1da177e4 LT	195	mtctl %r1, %cr18 /* IIAOQ head */
	196	ldo 4(%r1), %r1
	197	mtctl %r1, %cr18 /* IIAOQ tail */
	198	load32 KERNEL_PSW, %r1
	199	mtctl %r1, %cr22
	200	rfi
	201
	202	nop
	203	nop
	204	nop
	205	nop
	206	nop
	207	nop
	208	nop
	209	nop
	210	rfi_r2v_1:
	211	tovirt_r1 %r2
	212	bv 0(%r2)
	213	nop
	214
	215	#ifdef __LP64__
	216
	217	/********************** 64-bit real-mode calls *********************/
	218	/* This is only usable in wide kernels right now and will probably stay so */
	219	.text
	220	.export real64_call_asm
	221	/* unsigned long real64_call_asm(unsigned long *sp,
	222	* unsigned long *arg0p,
	223	* unsigned long fn)
	224	* sp is value of stack pointer to adopt before calling PDC (virt)
	225	* arg0p points to where saved arg values may be found
	226	* iodc_fn is the IODC function to call
	227	*/
	228	real64_call_asm:
	229	std %rp, -0x10(%sp) /* save RP */
	230	std %sp, -8(%arg0) /* save SP on real-mode stack */
	231	copy %arg0, %sp /* adopt the real-mode SP */
	232
	233	/* save fn */
	234	copy %arg2, %r31
	235
	236	/* set up the new ap */
	237	ldo 64(%arg1), %r29
	238
	239	/* load up the arg registers from the saved arg area */
	240	/* 32-bit calling convention passes first 4 args in registers */
	241	ldd 0REG_SZ(%arg1), %arg0 / note overwriting arg0 */
	242	ldd 2*REG_SZ(%arg1), %arg2
	243	ldd 3*REG_SZ(%arg1), %arg3
	244	ldd 4*REG_SZ(%arg1), %r22
	245	ldd 5*REG_SZ(%arg1), %r21
	246	ldd 6*REG_SZ(%arg1), %r20
	247	ldd 7*REG_SZ(%arg1), %r19
	248	ldd 1REG_SZ(%arg1), %arg1 / do this one last! */
	249
	250	tophys_r1 %sp
	251
	252	b,l rfi_virt2real,%r2
	253	nop
	254
	255	b,l save_control_regs,%r2 /* modifies r1, r2, r28 */
	256	nop
	257
	258	load32 PA(r64_ret), %r2
259	bv 0(%r31)
260	nop
261	r64_ret:
262	/* restore CRs before going virtual in case we page fault */
263	b,l restore_control_regs, %r2 /* modifies r1, r2, r26 */
264	nop
265
266	b,l rfi_real2virt,%r2
267	nop
268
269	tovirt_r1 %sp
270	ldd -8(%sp), %sp /* restore SP */
271	ldd -0x10(%sp), %rp /* restore RP */
272	bv 0(%rp)
273	nop
274
275	#endif
276
277	.export pc_in_user_space
278	.text
279	/* Doesn't belong here but I couldn't find a nicer spot. */
280	/* Should never get called, only used by profile stuff in time.c */
281	pc_in_user_space:
282	bv,n 0(%rp)
283	nop
284
285
286	.export __canonicalize_funcptr_for_compare
287	.text
288	/* http://lists.parisc-linux.org/hypermail/parisc-linux/10916.html
289	** GCC 3.3 and later has a new function in libgcc.a for
290	** comparing function pointers.
291	*/
292	__canonicalize_funcptr_for_compare:
293	#ifdef __LP64__
294	bve (%r2)
295	#else
296	bv %r0(%r2)
297	#endif
298	copy %r26,%r28