xref: /linux/arch/parisc/kernel/head.S (revision 7b12b9137930eb821b68e1bfa11e9de692208620)
1/* This file is subject to the terms and conditions of the GNU General Public
2 * License.  See the file "COPYING" in the main directory of this archive
3 * for more details.
4 *
5 * Copyright (C) 1999 by Helge Deller
6 * Copyright 1999 SuSE GmbH (Philipp Rumpf)
7 * Copyright 1999 Philipp Rumpf (prumpf@tux.org)
8 * Copyright 2000 Hewlett Packard (Paul Bame, bame@puffin.external.hp.com)
9 * Copyright (C) 2001 Grant Grundler (Hewlett Packard)
10 * Copyright (C) 2004 Kyle McMartin <kyle@debian.org>
11 *
12 * Initial Version 04-23-1999 by Helge Deller <deller@gmx.de>
13 */
14
15#include <linux/config.h>	/* for CONFIG_SMP */
16
17#include <asm/asm-offsets.h>
18#include <asm/psw.h>
19#include <asm/pdc.h>
20
21#include <asm/assembly.h>
22#include <asm/pgtable.h>
23
24	.level	LEVEL
25
26	.data
27
28	.export boot_args
29boot_args:
30	.word 0 /* arg0 */
31	.word 0 /* arg1 */
32	.word 0 /* arg2 */
33	.word 0 /* arg3 */
34
35	.text
36	.align	4
37	.import init_thread_union,data
38	.import fault_vector_20,code    /* IVA parisc 2.0 32 bit */
39#ifndef CONFIG_64BIT
40        .import fault_vector_11,code    /* IVA parisc 1.1 32 bit */
41	.import	$global$		/* forward declaration */
42#endif /*!CONFIG_64BIT*/
43	.export stext
44	.export _stext,data		/* Kernel want it this way! */
45_stext:
46stext:
47	.proc
48	.callinfo
49
50	/* Make sure sr4-sr7 are set to zero for the kernel address space */
51	mtsp	%r0,%sr4
52	mtsp	%r0,%sr5
53	mtsp	%r0,%sr6
54	mtsp	%r0,%sr7
55
56	/* Clear BSS (shouldn't the boot loader do this?) */
57
58	.import __bss_start,data
59	.import __bss_stop,data
60
61	load32		PA(__bss_start),%r3
62	load32		PA(__bss_stop),%r4
63$bss_loop:
64	cmpb,<<,n       %r3,%r4,$bss_loop
65	stw,ma          %r0,4(%r3)
66
67	/* Save away the arguments the boot loader passed in (32 bit args) */
68	load32		PA(boot_args),%r1
69	stw,ma          %arg0,4(%r1)
70	stw,ma          %arg1,4(%r1)
71	stw,ma          %arg2,4(%r1)
72	stw,ma          %arg3,4(%r1)
73
74	/* Initialize startup VM. Just map first 8/16 MB of memory */
75	load32		PA(swapper_pg_dir),%r4
76	mtctl		%r4,%cr24	/* Initialize kernel root pointer */
77	mtctl		%r4,%cr25	/* Initialize user root pointer */
78
79#if PT_NLEVELS == 3
80	/* Set pmd in pgd */
81	load32		PA(pmd0),%r5
82	shrd            %r5,PxD_VALUE_SHIFT,%r3
83	ldo		(PxD_FLAG_PRESENT+PxD_FLAG_VALID)(%r3),%r3
84	stw		%r3,ASM_PGD_ENTRY*ASM_PGD_ENTRY_SIZE(%r4)
85	ldo		ASM_PMD_ENTRY*ASM_PMD_ENTRY_SIZE(%r5),%r4
86#else
87	/* 2-level page table, so pmd == pgd */
88	ldo		ASM_PGD_ENTRY*ASM_PGD_ENTRY_SIZE(%r4),%r4
89#endif
90
91	/* Fill in pmd with enough pte directories */
92	load32		PA(pg0),%r1
93	SHRREG		%r1,PxD_VALUE_SHIFT,%r3
94	ldo		(PxD_FLAG_PRESENT+PxD_FLAG_VALID)(%r3),%r3
95
96	ldi		ASM_PT_INITIAL,%r1
97
981:
99	stw		%r3,0(%r4)
100	ldo		(ASM_PAGE_SIZE >> PxD_VALUE_SHIFT)(%r3),%r3
101	addib,>		-1,%r1,1b
102#if PT_NLEVELS == 3
103	ldo             ASM_PMD_ENTRY_SIZE(%r4),%r4
104#else
105	ldo             ASM_PGD_ENTRY_SIZE(%r4),%r4
106#endif
107
108
109	/* Now initialize the PTEs themselves */
110	ldo		0+_PAGE_KERNEL(%r0),%r3 /* Hardwired 0 phys addr start */
111	ldi		(1<<(KERNEL_INITIAL_ORDER-PAGE_SHIFT)),%r11 /* PFN count */
112	load32		PA(pg0),%r1
113
114$pgt_fill_loop:
115	STREGM          %r3,ASM_PTE_ENTRY_SIZE(%r1)
116	ldo		(1<<PFN_PTE_SHIFT)(%r3),%r3 /* add one PFN */
117	addib,>		-1,%r11,$pgt_fill_loop
118	nop
119
120	/* Load the return address...er...crash 'n burn */
121	copy		%r0,%r2
122
123	/* And the RFI Target address too */
124	load32		start_kernel,%r11
125
126	/* And the initial task pointer */
127	load32		init_thread_union,%r6
128	mtctl           %r6,%cr30
129
130	/* And the stack pointer too */
131	ldo             THREAD_SZ_ALGN(%r6),%sp
132
133	/* And the interrupt stack */
134	load32		interrupt_stack,%r6
135	mtctl           %r6,%cr31
136
137#ifdef CONFIG_SMP
138	/* Set the smp rendevous address into page zero.
139	** It would be safer to do this in init_smp_config() but
140	** it's just way easier to deal with here because
141	** of 64-bit function ptrs and the address is local to this file.
142	*/
143	load32		PA(smp_slave_stext),%r10
144	stw		%r10,0x10(%r0)	/* MEM_RENDEZ */
145	stw		%r0,0x28(%r0)	/* MEM_RENDEZ_HI - assume addr < 4GB */
146
147	/* FALLTHROUGH */
148	.procend
149
150	/*
151	** Code Common to both Monarch and Slave processors.
152	** Entry:
153	**
154	**  1.1:
155	**    %r11 must contain RFI target address.
156	**    %r25/%r26 args to pass to target function
157	**    %r2  in case rfi target decides it didn't like something
158	**
159	**  2.0w:
160	**    %r3  PDCE_PROC address
161	**    %r11 RFI target address
162	**
163	** Caller must init: SR4-7, %sp, %r10, %cr24/25,
164	*/
165common_stext:
166	.proc
167	.callinfo
168#else
169	/* Clear PDC entry point - we won't use it */
170	stw		%r0,0x10(%r0)	/* MEM_RENDEZ */
171	stw		%r0,0x28(%r0)	/* MEM_RENDEZ_HI */
172#endif /*CONFIG_SMP*/
173
174#ifdef CONFIG_64BIT
175	tophys_r1	%sp
176
177	/* Save the rfi target address */
178	ldd             TI_TASK-THREAD_SZ_ALGN(%sp), %r10
179	tophys_r1       %r10
180	std             %r11,  TASK_PT_GR11(%r10)
181	/* Switch to wide mode Superdome doesn't support narrow PDC
182	** calls.
183	*/
1841:	mfia            %rp             /* clear upper part of pcoq */
185	ldo             2f-1b(%rp),%rp
186	depdi           0,31,32,%rp
187	bv              (%rp)
188	ssm             PSW_SM_W,%r0
189
190        /* Set Wide mode as the "Default" (eg for traps)
191        ** First trap occurs *right* after (or part of) rfi for slave CPUs.
192        ** Someday, palo might not do this for the Monarch either.
193        */
1942:
195#define MEM_PDC_LO 0x388
196#define MEM_PDC_HI 0x35C
197	ldw             MEM_PDC_LO(%r0),%r3
198	ldw             MEM_PDC_HI(%r0),%r6
199	depd            %r6, 31, 32, %r3        /* move to upper word */
200
201	ldo             PDC_PSW(%r0),%arg0              /* 21 */
202	ldo             PDC_PSW_SET_DEFAULTS(%r0),%arg1 /* 2 */
203	ldo             PDC_PSW_WIDE_BIT(%r0),%arg2     /* 2 */
204	load32          PA(stext_pdc_ret), %rp
205	bv              (%r3)
206	copy            %r0,%arg3
207
208stext_pdc_ret:
209	/* restore rfi target address*/
210	ldd             TI_TASK-THREAD_SZ_ALGN(%sp), %r10
211	tophys_r1       %r10
212	ldd             TASK_PT_GR11(%r10), %r11
213	tovirt_r1       %sp
214#endif
215
216	/* PARANOID: clear user scratch/user space SR's */
217	mtsp	%r0,%sr0
218	mtsp	%r0,%sr1
219	mtsp	%r0,%sr2
220	mtsp	%r0,%sr3
221
222	/* Initialize Protection Registers */
223	mtctl	%r0,%cr8
224	mtctl	%r0,%cr9
225	mtctl	%r0,%cr12
226	mtctl	%r0,%cr13
227
228	/* Initialize the global data pointer */
229	loadgp
230
231	/* Set up our interrupt table.  HPMCs might not work after this!
232	 *
233	 * We need to install the correct iva for PA1.1 or PA2.0. The
234	 * following short sequence of instructions can determine this
235	 * (without being illegal on a PA1.1 machine).
236	 */
237#ifndef CONFIG_64BIT
238	ldi		32,%r10
239	mtctl		%r10,%cr11
240	.level 2.0
241	mfctl,w		%cr11,%r10
242	.level 1.1
243	comib,<>,n	0,%r10,$is_pa20
244	ldil		L%PA(fault_vector_11),%r10
245	b		$install_iva
246	ldo		R%PA(fault_vector_11)(%r10),%r10
247
248$is_pa20:
249	.level		LEVEL /* restore 1.1 || 2.0w */
250#endif /*!CONFIG_64BIT*/
251	load32		PA(fault_vector_20),%r10
252
253$install_iva:
254	mtctl		%r10,%cr14
255
256	b		aligned_rfi  /* Prepare to RFI! Man all the cannons! */
257	nop
258
259	.align 128
260aligned_rfi:
261	pcxt_ssm_bug
262
263	rsm		PSW_SM_QUIET,%r0	/* off troublesome PSW bits */
264	/* Don't need NOPs, have 8 compliant insn before rfi */
265
266	mtctl		%r0,%cr17	/* Clear IIASQ tail */
267	mtctl		%r0,%cr17	/* Clear IIASQ head */
268
269	/* Load RFI target into PC queue */
270	mtctl		%r11,%cr18	/* IIAOQ head */
271	ldo		4(%r11),%r11
272	mtctl		%r11,%cr18	/* IIAOQ tail */
273
274	load32		KERNEL_PSW,%r10
275	mtctl		%r10,%ipsw
276
277	/* Jump through hyperspace to Virt Mode */
278	rfi
279	nop
280
281	.procend
282
283#ifdef CONFIG_SMP
284
285	.import smp_init_current_idle_task,data
286	.import	smp_callin,code
287
288#ifndef CONFIG_64BIT
289smp_callin_rtn:
290        .proc
291	.callinfo
292	break	1,1		/*  Break if returned from start_secondary */
293	nop
294	nop
295        .procend
296#endif /*!CONFIG_64BIT*/
297
298/***************************************************************************
299* smp_slave_stext is executed by all non-monarch Processors when the Monarch
300* pokes the slave CPUs in smp.c:smp_boot_cpus().
301*
302* Once here, registers values are initialized in order to branch to virtual
303* mode. Once all available/eligible CPUs are in virtual mode, all are
304* released and start out by executing their own idle task.
305*****************************************************************************/
306smp_slave_stext:
307        .proc
308	.callinfo
309
310	/*
311	** Initialize Space registers
312	*/
313	mtsp	   %r0,%sr4
314	mtsp	   %r0,%sr5
315	mtsp	   %r0,%sr6
316	mtsp	   %r0,%sr7
317
318	/*  Initialize the SP - monarch sets up smp_init_current_idle_task */
319	load32		PA(smp_init_current_idle_task),%sp
320	LDREG		0(%sp),%sp	/* load task address */
321	tophys_r1	%sp
322	LDREG		TASK_THREAD_INFO(%sp),%sp
323	mtctl           %sp,%cr30       /* store in cr30 */
324	ldo             THREAD_SZ_ALGN(%sp),%sp
325
326	/* point CPU to kernel page tables */
327	load32		PA(swapper_pg_dir),%r4
328	mtctl		%r4,%cr24	/* Initialize kernel root pointer */
329	mtctl		%r4,%cr25	/* Initialize user root pointer */
330
331#ifdef CONFIG_64BIT
332	/* Setup PDCE_PROC entry */
333	copy            %arg0,%r3
334#else
335	/* Load RFI *return* address in case smp_callin bails */
336	load32		smp_callin_rtn,%r2
337#endif
338
339	/* Load RFI target address.  */
340	load32		smp_callin,%r11
341
342	/* ok...common code can handle the rest */
343	b		common_stext
344	nop
345
346	.procend
347#endif /* CONFIG_SMP */
348#ifndef CONFIG_64BIT
349	.data
350
351	.align	4
352	.export	$global$,data
353
354	.type	$global$,@object
355	.size	$global$,4
356$global$:
357	.word 0
358#endif /*!CONFIG_64BIT*/
359