xref: /openbmc/linux/arch/mips/kernel/cps-vec.S (revision 842b6b16) 
1/*
2 * Copyright (C) 2013 Imagination Technologies
3 * Author: Paul Burton <paul.burton@imgtec.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation;  either version 2 of the  License, or (at your
8 * option) any later version.
9 */
10
11#include <asm/addrspace.h>
12#include <asm/asm.h>
13#include <asm/asm-offsets.h>
14#include <asm/asmmacro.h>
15#include <asm/cacheops.h>
16#include <asm/eva.h>
17#include <asm/mipsregs.h>
18#include <asm/mipsmtregs.h>
19#include <asm/pm.h>
20
21#define GCR_CL_COHERENCE_OFS	0x2008
22#define GCR_CL_ID_OFS		0x2028
23
24.extern mips_cm_base
25
26.set noreorder
27
28#ifdef CONFIG_64BIT
29# define STATUS_BITDEPS		ST0_KX
30#else
31# define STATUS_BITDEPS		0
32#endif
33
34#ifdef CONFIG_MIPS_CPS_NS16550
35
36#define DUMP_EXCEP(name)		\
37	PTR_LA	a0, 8f;			\
38	jal	mips_cps_bev_dump;	\
39	 nop;				\
40	TEXT(name)
41
42#else /* !CONFIG_MIPS_CPS_NS16550 */
43
44#define DUMP_EXCEP(name)
45
46#endif /* !CONFIG_MIPS_CPS_NS16550 */
47
48	/*
49	 * Set dest to non-zero if the core supports the MT ASE, else zero. If
50	 * MT is not supported then branch to nomt.
51	 */
52	.macro	has_mt	dest, nomt
53	mfc0	\dest, CP0_CONFIG, 1
54	bgez	\dest, \nomt
55	 mfc0	\dest, CP0_CONFIG, 2
56	bgez	\dest, \nomt
57	 mfc0	\dest, CP0_CONFIG, 3
58	andi	\dest, \dest, MIPS_CONF3_MT
59	beqz	\dest, \nomt
60	 nop
61	.endm
62
63.section .text.cps-vec
64.balign 0x1000
65
66LEAF(mips_cps_core_entry)
67	/*
68	 * These first 4 bytes will be patched by cps_smp_setup to load the
69	 * CCA to use into register s0.
70	 */
71	.word	0
72
73	/* Check whether we're here due to an NMI */
74	mfc0	k0, CP0_STATUS
75	and	k0, k0, ST0_NMI
76	beqz	k0, not_nmi
77	 nop
78
79	/* This is an NMI */
80	PTR_LA	k0, nmi_handler
81	jr	k0
82	 nop
83
84not_nmi:
85	/* Setup Cause */
86	li	t0, CAUSEF_IV
87	mtc0	t0, CP0_CAUSE
88
89	/* Setup Status */
90	li	t0, ST0_CU1 | ST0_CU0 | ST0_BEV | STATUS_BITDEPS
91	mtc0	t0, CP0_STATUS
92
93	/*
94	 * Clear the bits used to index the caches. Note that the architecture
95	 * dictates that writing to any of TagLo or TagHi selects 0 or 2 should
96	 * be valid for all MIPS32 CPUs, even those for which said writes are
97	 * unnecessary.
98	 */
99	mtc0	zero, CP0_TAGLO, 0
100	mtc0	zero, CP0_TAGHI, 0
101	mtc0	zero, CP0_TAGLO, 2
102	mtc0	zero, CP0_TAGHI, 2
103	ehb
104
105	/* Primary cache configuration is indicated by Config1 */
106	mfc0	v0, CP0_CONFIG, 1
107
108	/* Detect I-cache line size */
109	_EXT	t0, v0, MIPS_CONF1_IL_SHF, MIPS_CONF1_IL_SZ
110	beqz	t0, icache_done
111	 li	t1, 2
112	sllv	t0, t1, t0
113
114	/* Detect I-cache size */
115	_EXT	t1, v0, MIPS_CONF1_IS_SHF, MIPS_CONF1_IS_SZ
116	xori	t2, t1, 0x7
117	beqz	t2, 1f
118	 li	t3, 32
119	addiu	t1, t1, 1
120	sllv	t1, t3, t1
1211:	/* At this point t1 == I-cache sets per way */
122	_EXT	t2, v0, MIPS_CONF1_IA_SHF, MIPS_CONF1_IA_SZ
123	addiu	t2, t2, 1
124	mul	t1, t1, t0
125	mul	t1, t1, t2
126
127	li	a0, CKSEG0
128	PTR_ADD	a1, a0, t1
1291:	cache	Index_Store_Tag_I, 0(a0)
130	PTR_ADD	a0, a0, t0
131	bne	a0, a1, 1b
132	 nop
133icache_done:
134
135	/* Detect D-cache line size */
136	_EXT	t0, v0, MIPS_CONF1_DL_SHF, MIPS_CONF1_DL_SZ
137	beqz	t0, dcache_done
138	 li	t1, 2
139	sllv	t0, t1, t0
140
141	/* Detect D-cache size */
142	_EXT	t1, v0, MIPS_CONF1_DS_SHF, MIPS_CONF1_DS_SZ
143	xori	t2, t1, 0x7
144	beqz	t2, 1f
145	 li	t3, 32
146	addiu	t1, t1, 1
147	sllv	t1, t3, t1
1481:	/* At this point t1 == D-cache sets per way */
149	_EXT	t2, v0, MIPS_CONF1_DA_SHF, MIPS_CONF1_DA_SZ
150	addiu	t2, t2, 1
151	mul	t1, t1, t0
152	mul	t1, t1, t2
153
154	li	a0, CKSEG0
155	PTR_ADDU a1, a0, t1
156	PTR_SUBU a1, a1, t0
1571:	cache	Index_Store_Tag_D, 0(a0)
158	bne	a0, a1, 1b
159	 PTR_ADD a0, a0, t0
160dcache_done:
161
162	/* Set Kseg0 CCA to that in s0 */
163	mfc0	t0, CP0_CONFIG
164	ori	t0, 0x7
165	xori	t0, 0x7
166	or	t0, t0, s0
167	mtc0	t0, CP0_CONFIG
168	ehb
169
170	/* Calculate an uncached address for the CM GCRs */
171	MFC0	v1, CP0_CMGCRBASE
172	PTR_SLL	v1, v1, 4
173	PTR_LI	t0, UNCAC_BASE
174	PTR_ADDU v1, v1, t0
175
176	/* Enter the coherent domain */
177	li	t0, 0xff
178	sw	t0, GCR_CL_COHERENCE_OFS(v1)
179	ehb
180
181	/* Jump to kseg0 */
182	PTR_LA	t0, 1f
183	jr	t0
184	 nop
185
186	/*
187	 * We're up, cached & coherent. Perform any further required core-level
188	 * initialisation.
189	 */
1901:	jal	mips_cps_core_init
191	 nop
192
193	/* Do any EVA initialization if necessary */
194	eva_init
195
196	/*
197	 * Boot any other VPEs within this core that should be online, and
198	 * deactivate this VPE if it should be offline.
199	 */
200	jal	mips_cps_boot_vpes
201	 nop
202
203	/* Off we go! */
204	PTR_L	t1, VPEBOOTCFG_PC(v0)
205	PTR_L	gp, VPEBOOTCFG_GP(v0)
206	PTR_L	sp, VPEBOOTCFG_SP(v0)
207	jr	t1
208	 nop
209	END(mips_cps_core_entry)
210
211.org 0x200
212LEAF(excep_tlbfill)
213	DUMP_EXCEP("TLB Fill")
214	b	.
215	 nop
216	END(excep_tlbfill)
217
218.org 0x280
219LEAF(excep_xtlbfill)
220	DUMP_EXCEP("XTLB Fill")
221	b	.
222	 nop
223	END(excep_xtlbfill)
224
225.org 0x300
226LEAF(excep_cache)
227	DUMP_EXCEP("Cache")
228	b	.
229	 nop
230	END(excep_cache)
231
232.org 0x380
233LEAF(excep_genex)
234	DUMP_EXCEP("General")
235	b	.
236	 nop
237	END(excep_genex)
238
239.org 0x400
240LEAF(excep_intex)
241	DUMP_EXCEP("Interrupt")
242	b	.
243	 nop
244	END(excep_intex)
245
246.org 0x480
247LEAF(excep_ejtag)
248	DUMP_EXCEP("EJTAG")
249	PTR_LA	k0, ejtag_debug_handler
250	jr	k0
251	 nop
252	END(excep_ejtag)
253
254LEAF(mips_cps_core_init)
255#ifdef CONFIG_MIPS_MT_SMP
256	/* Check that the core implements the MT ASE */
257	has_mt	t0, 3f
258
259	.set	push
260	.set	mt
261
262	/* Only allow 1 TC per VPE to execute... */
263	dmt
264
265	/* ...and for the moment only 1 VPE */
266	dvpe
267	PTR_LA	t1, 1f
268	jr.hb	t1
269	 nop
270
271	/* Enter VPE configuration state */
2721:	mfc0	t0, CP0_MVPCONTROL
273	ori	t0, t0, MVPCONTROL_VPC
274	mtc0	t0, CP0_MVPCONTROL
275
276	/* Retrieve the number of VPEs within the core */
277	mfc0	t0, CP0_MVPCONF0
278	srl	t0, t0, MVPCONF0_PVPE_SHIFT
279	andi	t0, t0, (MVPCONF0_PVPE >> MVPCONF0_PVPE_SHIFT)
280	addiu	ta3, t0, 1
281
282	/* If there's only 1, we're done */
283	beqz	t0, 2f
284	 nop
285
286	/* Loop through each VPE within this core */
287	li	ta1, 1
288
2891:	/* Operate on the appropriate TC */
290	mtc0	ta1, CP0_VPECONTROL
291	ehb
292
293	/* Bind TC to VPE (1:1 TC:VPE mapping) */
294	mttc0	ta1, CP0_TCBIND
295
296	/* Set exclusive TC, non-active, master */
297	li	t0, VPECONF0_MVP
298	sll	t1, ta1, VPECONF0_XTC_SHIFT
299	or	t0, t0, t1
300	mttc0	t0, CP0_VPECONF0
301
302	/* Set TC non-active, non-allocatable */
303	mttc0	zero, CP0_TCSTATUS
304
305	/* Set TC halted */
306	li	t0, TCHALT_H
307	mttc0	t0, CP0_TCHALT
308
309	/* Next VPE */
310	addiu	ta1, ta1, 1
311	slt	t0, ta1, ta3
312	bnez	t0, 1b
313	 nop
314
315	/* Leave VPE configuration state */
3162:	mfc0	t0, CP0_MVPCONTROL
317	xori	t0, t0, MVPCONTROL_VPC
318	mtc0	t0, CP0_MVPCONTROL
319
3203:	.set	pop
321#endif
322	jr	ra
323	 nop
324	END(mips_cps_core_init)
325
326LEAF(mips_cps_boot_vpes)
327	/* Retrieve CM base address */
328	PTR_LA	t0, mips_cm_base
329	PTR_L	t0, 0(t0)
330
331	/* Calculate a pointer to this cores struct core_boot_config */
332	lw	t0, GCR_CL_ID_OFS(t0)
333	li	t1, COREBOOTCFG_SIZE
334	mul	t0, t0, t1
335	PTR_LA	t1, mips_cps_core_bootcfg
336	PTR_L	t1, 0(t1)
337	PTR_ADDU t0, t0, t1
338
339	/* Calculate this VPEs ID. If the core doesn't support MT use 0 */
340	li	t9, 0
341#ifdef CONFIG_MIPS_MT_SMP
342	has_mt	ta2, 1f
343
344	/* Find the number of VPEs present in the core */
345	mfc0	t1, CP0_MVPCONF0
346	srl	t1, t1, MVPCONF0_PVPE_SHIFT
347	andi	t1, t1, MVPCONF0_PVPE >> MVPCONF0_PVPE_SHIFT
348	addiu	t1, t1, 1
349
350	/* Calculate a mask for the VPE ID from EBase.CPUNum */
351	clz	t1, t1
352	li	t2, 31
353	subu	t1, t2, t1
354	li	t2, 1
355	sll	t1, t2, t1
356	addiu	t1, t1, -1
357
358	/* Retrieve the VPE ID from EBase.CPUNum */
359	mfc0	t9, $15, 1
360	and	t9, t9, t1
361#endif
362
3631:	/* Calculate a pointer to this VPEs struct vpe_boot_config */
364	li	t1, VPEBOOTCFG_SIZE
365	mul	v0, t9, t1
366	PTR_L	ta3, COREBOOTCFG_VPECONFIG(t0)
367	PTR_ADDU v0, v0, ta3
368
369#ifdef CONFIG_MIPS_MT_SMP
370
371	/* If the core doesn't support MT then return */
372	bnez	ta2, 1f
373	 nop
374	jr	ra
375	 nop
376
377	.set	push
378	.set	mt
379
3801:	/* Enter VPE configuration state */
381	dvpe
382	PTR_LA	t1, 1f
383	jr.hb	t1
384	 nop
3851:	mfc0	t1, CP0_MVPCONTROL
386	ori	t1, t1, MVPCONTROL_VPC
387	mtc0	t1, CP0_MVPCONTROL
388	ehb
389
390	/* Loop through each VPE */
391	PTR_L	ta2, COREBOOTCFG_VPEMASK(t0)
392	move	t8, ta2
393	li	ta1, 0
394
395	/* Check whether the VPE should be running. If not, skip it */
3961:	andi	t0, ta2, 1
397	beqz	t0, 2f
398	 nop
399
400	/* Operate on the appropriate TC */
401	mfc0	t0, CP0_VPECONTROL
402	ori	t0, t0, VPECONTROL_TARGTC
403	xori	t0, t0, VPECONTROL_TARGTC
404	or	t0, t0, ta1
405	mtc0	t0, CP0_VPECONTROL
406	ehb
407
408	/* Skip the VPE if its TC is not halted */
409	mftc0	t0, CP0_TCHALT
410	beqz	t0, 2f
411	 nop
412
413	/* Calculate a pointer to the VPEs struct vpe_boot_config */
414	li	t0, VPEBOOTCFG_SIZE
415	mul	t0, t0, ta1
416	addu	t0, t0, ta3
417
418	/* Set the TC restart PC */
419	lw	t1, VPEBOOTCFG_PC(t0)
420	mttc0	t1, CP0_TCRESTART
421
422	/* Set the TC stack pointer */
423	lw	t1, VPEBOOTCFG_SP(t0)
424	mttgpr	t1, sp
425
426	/* Set the TC global pointer */
427	lw	t1, VPEBOOTCFG_GP(t0)
428	mttgpr	t1, gp
429
430	/* Copy config from this VPE */
431	mfc0	t0, CP0_CONFIG
432	mttc0	t0, CP0_CONFIG
433
434	/* Ensure no software interrupts are pending */
435	mttc0	zero, CP0_CAUSE
436	mttc0	zero, CP0_STATUS
437
438	/* Set TC active, not interrupt exempt */
439	mftc0	t0, CP0_TCSTATUS
440	li	t1, ~TCSTATUS_IXMT
441	and	t0, t0, t1
442	ori	t0, t0, TCSTATUS_A
443	mttc0	t0, CP0_TCSTATUS
444
445	/* Clear the TC halt bit */
446	mttc0	zero, CP0_TCHALT
447
448	/* Set VPE active */
449	mftc0	t0, CP0_VPECONF0
450	ori	t0, t0, VPECONF0_VPA
451	mttc0	t0, CP0_VPECONF0
452
453	/* Next VPE */
4542:	srl	ta2, ta2, 1
455	addiu	ta1, ta1, 1
456	bnez	ta2, 1b
457	 nop
458
459	/* Leave VPE configuration state */
460	mfc0	t1, CP0_MVPCONTROL
461	xori	t1, t1, MVPCONTROL_VPC
462	mtc0	t1, CP0_MVPCONTROL
463	ehb
464	evpe
465
466	/* Check whether this VPE is meant to be running */
467	li	t0, 1
468	sll	t0, t0, t9
469	and	t0, t0, t8
470	bnez	t0, 2f
471	 nop
472
473	/* This VPE should be offline, halt the TC */
474	li	t0, TCHALT_H
475	mtc0	t0, CP0_TCHALT
476	PTR_LA	t0, 1f
4771:	jr.hb	t0
478	 nop
479
4802:	.set	pop
481
482#endif /* CONFIG_MIPS_MT_SMP */
483
484	/* Return */
485	jr	ra
486	 nop
487	END(mips_cps_boot_vpes)
488
489#if defined(CONFIG_MIPS_CPS_PM) && defined(CONFIG_CPU_PM)
490
491	/* Calculate a pointer to this CPUs struct mips_static_suspend_state */
492	.macro	psstate	dest
493	.set	push
494	.set	noat
495	lw	$1, TI_CPU(gp)
496	sll	$1, $1, LONGLOG
497	PTR_LA	\dest, __per_cpu_offset
498	addu	$1, $1, \dest
499	lw	$1, 0($1)
500	PTR_LA	\dest, cps_cpu_state
501	addu	\dest, \dest, $1
502	.set	pop
503	.endm
504
505LEAF(mips_cps_pm_save)
506	/* Save CPU state */
507	SUSPEND_SAVE_REGS
508	psstate	t1
509	SUSPEND_SAVE_STATIC
510	jr	v0
511	 nop
512	END(mips_cps_pm_save)
513
514LEAF(mips_cps_pm_restore)
515	/* Restore CPU state */
516	psstate	t1
517	RESUME_RESTORE_STATIC
518	RESUME_RESTORE_REGS_RETURN
519	END(mips_cps_pm_restore)
520
521#endif /* CONFIG_MIPS_CPS_PM && CONFIG_CPU_PM */
522