[deliverable/linux.git] / arch / mips / kernel / relocate_kernel.S

/*
 * relocate_kernel.S for kexec
 * Created by <nschichan@corp.free.fr> on Thu Oct 12 17:49:57 2006
 *
 * This source code is licensed under the GNU General Public License,
 * Version 2.  See the file COPYING for more details.
 */

#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/regdef.h>
#include <asm/page.h>
#include <asm/mipsregs.h>
#include <asm/stackframe.h>
#include <asm/addrspace.h>

LEAF(relocate_new_kernel)
	PTR_L a0,	arg0
	PTR_L a1,	arg1
	PTR_L a2,	arg2
	PTR_L a3,	arg3

	PTR_L		s0, kexec_indirection_page
	PTR_L		s1, kexec_start_address

process_entry:
	PTR_L		s2, (s0)
	PTR_ADD		s0, s0, SZREG

	/* destination page */
	and		s3, s2, 0x1
	beq		s3, zero, 1f
	and		s4, s2, ~0x1	/* store destination addr in s4 */
	b		process_entry

1:
	/* indirection page, update s0  */
	and		s3, s2, 0x2
	beq		s3, zero, 1f
	and		s0, s2, ~0x2
	b		process_entry

1:
	/* done page */
	and		s3, s2, 0x4
	beq		s3, zero, 1f
	b		done
1:
	/* source page */
	and		s3, s2, 0x8
	beq		s3, zero, process_entry
	and		s2, s2, ~0x8
	li		s6, (1 << PAGE_SHIFT) / SZREG

copy_word:
	/* copy page word by word */
	REG_L		s5, (s2)
	REG_S		s5, (s4)
	PTR_ADD		s4, s4, SZREG
	PTR_ADD		s2, s2, SZREG
	LONG_SUB	s6, s6, 1
	beq		s6, zero, process_entry
	b		copy_word
	b		process_entry

done:
#ifdef CONFIG_SMP
	/* kexec_flag reset is signal to other CPUs what kernel
	   was moved to it's location. Note - we need relocated address
	   of kexec_flag.  */

	bal		1f
 1: 	move		t1,ra;
	PTR_LA		t2,1b
	PTR_LA		t0,kexec_flag
	PTR_SUB		t0,t0,t2;
	PTR_ADD		t0,t1,t0;
	LONG_S		zero,(t0)
#endif

#ifdef CONFIG_CPU_CAVIUM_OCTEON
	/* We need to flush I-cache before jumping to new kernel.
	 * Unfortunatelly, this code is cpu-specific.
	 */
	.set push
	.set noreorder
	syncw
	syncw
	synci		0($0)
	.set pop
#else
	sync
#endif
	/* jump to kexec_start_address */
	j		s1
	END(relocate_new_kernel)

#ifdef CONFIG_SMP
/*
 * Other CPUs should wait until code is relocated and
 * then start at entry (?) point.
 */
LEAF(kexec_smp_wait)
	PTR_L		a0, s_arg0
	PTR_L		a1, s_arg1
	PTR_L		a2, s_arg2
	PTR_L		a3, s_arg3
	PTR_L		s1, kexec_start_address

	/* Non-relocated address works for args and kexec_start_address ( old
	 * kernel is not overwritten). But we need relocated address of
	 * kexec_flag.
	 */

	bal		1f
1:	move		t1,ra;
	PTR_LA		t2,1b
	PTR_LA		t0,kexec_flag
	PTR_SUB		t0,t0,t2;
	PTR_ADD		t0,t1,t0;

1:	LONG_L		s0, (t0)
	bne		s0, zero,1b

#ifdef CONFIG_CPU_CAVIUM_OCTEON
	.set push
	.set noreorder
	synci		0($0)
	.set pop
#else
	sync
#endif
	j		s1
	END(kexec_smp_wait)
#endif

#ifdef __mips64
       /* all PTR's must be aligned to 8 byte in 64-bit mode */
       .align  3
#endif

/* All parameters to new kernel are passed in registers a0-a3.
 * kexec_args[0..3] are uses to prepare register values.
 */

kexec_args:
	EXPORT(kexec_args)
arg0:	PTR		0x0
arg1:	PTR		0x0
arg2:	PTR		0x0
arg3:	PTR		0x0
	.size	kexec_args,PTRSIZE*4

#ifdef CONFIG_SMP
/*
 * Secondary CPUs may have different kernel parameters in
 * their registers a0-a3. secondary_kexec_args[0..3] are used
 * to prepare register values.
 */
secondary_kexec_args:
	EXPORT(secondary_kexec_args)
s_arg0:	PTR		0x0
s_arg1:	PTR		0x0
s_arg2:	PTR		0x0
s_arg3:	PTR		0x0
	.size	secondary_kexec_args,PTRSIZE*4
kexec_flag:
	LONG		0x1

#endif

kexec_start_address:
	EXPORT(kexec_start_address)
	PTR		0x0
	.size		kexec_start_address, PTRSIZE

kexec_indirection_page:
	EXPORT(kexec_indirection_page)
	PTR		0
	.size		kexec_indirection_page, PTRSIZE

relocate_new_kernel_end:

relocate_new_kernel_size:
	EXPORT(relocate_new_kernel_size)
	PTR		relocate_new_kernel_end - relocate_new_kernel
	.size		relocate_new_kernel_size, PTRSIZE
Commit	Line	Data
583bb86f NS	1	/*
	2	* relocate_kernel.S for kexec
	3	* Created by <nschichan@corp.free.fr> on Thu Oct 12 17:49:57 2006
	4	*
	5	* This source code is licensed under the GNU General Public License,
	6	* Version 2. See the file COPYING for more details.
	7	*/
	8
	9	#include <asm/asm.h>
	10	#include <asm/asmmacro.h>
	11	#include <asm/regdef.h>
	12	#include <asm/page.h>
	13	#include <asm/mipsregs.h>
	14	#include <asm/stackframe.h>
	15	#include <asm/addrspace.h>
	16
00be0f30	17	LEAF(relocate_new_kernel)
7aa1c8f4 RB	18	PTR_L a0, arg0
	19	PTR_L a1, arg1
	20	PTR_L a2, arg2
	21	PTR_L a3, arg3
	22
00be0f30 RB	23	PTR_L s0, kexec_indirection_page
00be0f30 RB	24	PTR_L s1, kexec_start_address
583bb86f NS	25
583bb86f NS	26	process_entry:
00be0f30 RB	27	PTR_L s2, (s0)
00be0f30 RB	28	PTR_ADD s0, s0, SZREG
583bb86f NS	29
583bb86f NS	30	/* destination page */
00be0f30 RB	31	and s3, s2, 0x1
	32	beq s3, zero, 1f
	33	and s4, s2, ~0x1 /* store destination addr in s4 */
00be0f30	34	b process_entry
583bb86f NS	35
	36	1:
	37	/* indirection page, update s0 */
00be0f30 RB	38	and s3, s2, 0x2
	39	beq s3, zero, 1f
	40	and s0, s2, ~0x2
	41	b process_entry
583bb86f NS	42
	43	1:
	44	/* done page */
00be0f30 RB	45	and s3, s2, 0x4
	46	beq s3, zero, 1f
	47	b done
583bb86f NS	48	1:
583bb86f NS	49	/* source page */
00be0f30 RB	50	and s3, s2, 0x8
	51	beq s3, zero, process_entry
	52	and s2, s2, ~0x8
	53	li s6, (1 << PAGE_SHIFT) / SZREG
583bb86f NS	54
	55	copy_word:
	56	/* copy page word by word */
00be0f30 RB	57	REG_L s5, (s2)
	58	REG_S s5, (s4)
	59	PTR_ADD s4, s4, SZREG
	60	PTR_ADD s2, s2, SZREG
	61	LONG_SUB s6, s6, 1
	62	beq s6, zero, process_entry
	63	b copy_word
	64	b process_entry
583bb86f NS	65
583bb86f NS	66	done:
7aa1c8f4 RB	67	#ifdef CONFIG_SMP
	68	/* kexec_flag reset is signal to other CPUs what kernel
	69	was moved to it's location. Note - we need relocated address
	70	of kexec_flag. */
	71
	72	bal 1f
	73	1: move t1,ra;
	74	PTR_LA t2,1b
	75	PTR_LA t0,kexec_flag
	76	PTR_SUB t0,t0,t2;
	77	PTR_ADD t0,t1,t0;
	78	LONG_S zero,(t0)
	79	#endif
	80
abe77f90 RB	81	#ifdef CONFIG_CPU_CAVIUM_OCTEON
	82	/* We need to flush I-cache before jumping to new kernel.
	83	* Unfortunatelly, this code is cpu-specific.
	84	*/
	85	.set push
	86	.set noreorder
	87	syncw
	88	syncw
	89	synci 0($0)
	90	.set pop
	91	#else
7aa1c8f4	92	sync
abe77f90	93	#endif
583bb86f	94	/* jump to kexec_start_address */
00be0f30 RB	95	j s1
00be0f30 RB	96	END(relocate_new_kernel)
583bb86f	97
7aa1c8f4 RB	98	#ifdef CONFIG_SMP
	99	/*
	100	* Other CPUs should wait until code is relocated and
	101	* then start at entry (?) point.
	102	*/
	103	LEAF(kexec_smp_wait)
	104	PTR_L a0, s_arg0
	105	PTR_L a1, s_arg1
	106	PTR_L a2, s_arg2
	107	PTR_L a3, s_arg3
	108	PTR_L s1, kexec_start_address
	109
	110	/* Non-relocated address works for args and kexec_start_address ( old
	111	* kernel is not overwritten). But we need relocated address of
	112	* kexec_flag.
	113	*/
	114
	115	bal 1f
	116	1: move t1,ra;
	117	PTR_LA t2,1b
	118	PTR_LA t0,kexec_flag
	119	PTR_SUB t0,t0,t2;
	120	PTR_ADD t0,t1,t0;
	121
	122	1: LONG_L s0, (t0)
	123	bne s0, zero,1b
	124
abe77f90 RB	125	#ifdef CONFIG_CPU_CAVIUM_OCTEON
	126	.set push
	127	.set noreorder
	128	synci 0($0)
	129	.set pop
	130	#else
7aa1c8f4	131	sync
abe77f90	132	#endif
7aa1c8f4 RB	133	j s1
	134	END(kexec_smp_wait)
	135	#endif
	136
	137	#ifdef __mips64
	138	/* all PTR's must be aligned to 8 byte in 64-bit mode */
	139	.align 3
	140	#endif
	141
	142	/* All parameters to new kernel are passed in registers a0-a3.
	143	* kexec_args[0..3] are uses to prepare register values.
	144	*/
	145
	146	kexec_args:
	147	EXPORT(kexec_args)
	148	arg0: PTR 0x0
	149	arg1: PTR 0x0
	150	arg2: PTR 0x0
	151	arg3: PTR 0x0
	152	.size kexec_args,PTRSIZE*4
	153
	154	#ifdef CONFIG_SMP
	155	/*
	156	* Secondary CPUs may have different kernel parameters in
	157	* their registers a0-a3. secondary_kexec_args[0..3] are used
	158	* to prepare register values.
	159	*/
	160	secondary_kexec_args:
	161	EXPORT(secondary_kexec_args)
	162	s_arg0: PTR 0x0
	163	s_arg1: PTR 0x0
	164	s_arg2: PTR 0x0
	165	s_arg3: PTR 0x0
	166	.size secondary_kexec_args,PTRSIZE*4
	167	kexec_flag:
	168	LONG 0x1
	169
	170	#endif
	171
583bb86f	172	kexec_start_address:
00be0f30 RB	173	EXPORT(kexec_start_address)
	174	PTR 0x0
	175	.size kexec_start_address, PTRSIZE
583bb86f	176
583bb86f	177	kexec_indirection_page:
00be0f30 RB	178	EXPORT(kexec_indirection_page)
	179	PTR 0
	180	.size kexec_indirection_page, PTRSIZE
583bb86f NS	181
	182	relocate_new_kernel_end:
	183
583bb86f	184	relocate_new_kernel_size:
00be0f30 RB	185	EXPORT(relocate_new_kernel_size)
	186	PTR relocate_new_kernel_end - relocate_new_kernel
	187	.size relocate_new_kernel_size, PTRSIZE