/*
* Copyright 2011 Tilera Corporation. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
*
* copy new kernel into place and then call hv_reexec
*
*/
#include <linux/linkage.h>
#include <arch/chip.h>
#include <asm/page.h>
#include <hv/hypervisor.h>
#undef RELOCATE_NEW_KERNEL_VERBOSE
STD_ENTRY(relocate_new_kernel)
move r30, r0 /* page list */
move r31, r1 /* address of page we are on */
move r32, r2 /* start address of new kernel */
shrui r1, r1, PAGE_SHIFT
addi r1, r1, 1
shli sp, r1, PAGE_SHIFT
addi sp, sp, -8
/* we now have a stack (whether we need one or not) */
#ifdef RELOCATE_NEW_KERNEL_VERBOSE
moveli r40, hw2_last(hv_console_putc)
shl16insli r40, r40, hw1(hv_console_putc)
shl16insli r40, r40, hw0(hv_console_putc)
moveli r0, 'r'
jalr r40
moveli r0, '_'
jalr r40
moveli r0, 'n'
jalr r40
moveli r0, '_'
jalr r40
moveli r0, 'k'
jalr r40
moveli r0, '\n'
jalr r40
#endif
/*
* Throughout this code r30 is pointer to the element of page
* list we are working on.
*
* Normally we get to the next element of the page list by
* incrementing r30 by eight. The exception is if the element
* on the page list is an IND_INDIRECTION in which case we use
* the element with the low bits masked off as the new value
* of r30.
*
* To get this started, we need the value passed to us (which
* will always be an IND_INDIRECTION) in memory somewhere with
* r30 pointing at it. To do that, we push the value passed
* to us on the stack and make r30 point to it.
*/
st sp, r30
move r30, sp
addi sp, sp, -16
/*
* On TILE-GX, we need to flush all tiles' caches, since we may
* have been doing hash-for-home caching there. Note that we
* must do this _after_ we're completely done modifying any memory
* other than our output buffer (which we know is locally cached).
* We want the caches to be fully clean when we do the reexec,
* because the hypervisor is going to do this flush again at that
* point, and we don't want that second flush to overwrite any memory.
*/
{
move r0, zero /* cache_pa */
moveli r1, hw2_last(HV_FLUSH_EVICT_L2)
}
{
shl16insli r1, r1, hw1(HV_FLUSH_EVICT_L2)
movei r2, -1 /* cache_cpumask; -1 means all client tiles */
}
{
shl16insli r1, r1, hw0(HV_FLUSH_EVICT_L2) /* cache_control */
move r3, zero /* tlb_va */
}
{
move r4, zero /* tlb_length */
move r5, zero /* tlb_pgsize */
}
{
move r6, zero /* tlb_cpumask */
move r7, zero /* asids */
}
{
moveli r20, hw2_last(hv_flush_remote)
move r8, zero /* asidcount */
}
shl16insli r20, r20, hw1(hv_flush_remote)
shl16insli r20, r20, hw0(hv_flush_remote)
jalr r20
/* r33 is destination pointer, default to zero */
moveli r33, 0
.Lloop: ld r10, r30
andi r9, r10, 0xf /* low 4 bits tell us what type it is */
xor r10, r10, r9 /* r10 is now value with low 4 bits stripped */
cmpeqi r0, r9, 0x1 /* IND_DESTINATION */
beqzt r0, .Ltry2
move r33, r10
#ifdef RELOCATE_NEW_KERNEL_VERBOSE
moveli r0, 'd'
jalr r40
#endif
addi r30, r30, 8
j .Lloop
.Ltry2:
cmpeqi r0, r9, 0x2 /* IND_INDIRECTION */
beqzt r0, .Ltry4
move r30, r10
#ifdef RELOCATE_NEW_KERNEL_VERBOSE
moveli r0, 'i'
jalr r40
#endif
j .Lloop
.Ltry4:
cmpeqi r0, r9, 0x4 /* IND_DONE */
beqzt r0, .Ltry8
mf
#ifdef RELOCATE_NEW_KERNEL_VERBOSE
moveli r0, 'D'
jalr r40
moveli r0, '\n'
jalr r40
#endif
move r0, r32
moveli r41, hw2_last(hv_reexec)
shl16insli r41, r41, hw1(hv_reexec)
shl16insli r41, r41, hw0(hv_reexec)
jalr r41
/* we should not get here */
#ifdef RELOCATE_NEW_KERNEL_VERBOSE
moveli r0, '?'
jalr r40
moveli r0, '\n'
jalr r40
#endif
j .Lhalt
.Ltry8: cmpeqi r0, r9, 0x8 /* IND_SOURCE */
beqz r0, .Lerr /* unknown type */
/* copy page at r10 to page at r33 */
move r11, r33
moveli r0, hw2_last(PAGE_SIZE)
shl16insli r0, r0, hw1(PAGE_SIZE)
shl16insli r0, r0, hw0(PAGE_SIZE)
add r33, r33, r0
/* copy word at r10 to word at r11 until r11 equals r33 */
/* We know page size must be multiple of 8, so we can unroll
* 8 times safely without any edge case checking.
*
* Issue a flush of the destination every 8 words to avoid
* incoherence when starting the new kernel. (Now this is
* just good paranoia because the hv_reexec call will also
* take care of this.)
*/
1:
{ ld r0, r10; addi r10, r10, 8 }
{ st r11, r0; addi r11, r11, 8 }
{ ld r0, r10; addi r10, r10, 8 }
{ st r11, r0; addi r11, r11, 8 }
{ ld r0, r10; addi r10, r10, 8 }
{ st r11, r0; addi r11, r11, 8 }
{ ld r0, r10; addi r10, r10, 8 }
{ st r11, r0; addi r11, r11, 8 }
{ ld r0, r10; addi r10, r10, 8 }
{ st r11, r0; addi r11, r11, 8 }
{ ld r0, r10; addi r10, r10, 8 }
{ st r11, r0; addi r11, r11, 8 }
{ ld r0, r10; addi r10, r10, 8 }
{ st r11, r0; addi r11, r11, 8 }
{ ld r0, r10; addi r10, r10, 8 }
{ st r11, r0 }
{ flush r11 ; addi r11, r11, 8 }
cmpeq r0, r33, r11
beqzt r0, 1b
#ifdef RELOCATE_NEW_KERNEL_VERBOSE
moveli r0, 's'
jalr r40
#endif
addi r30, r30, 8
j .Lloop
.Lerr:
#ifdef RELOCATE_NEW_KERNEL_VERBOSE
moveli r0, 'e'
jalr r40
moveli r0, 'r'
jalr r40
moveli r0, 'r'
jalr r40
moveli r0, '\n'
jalr r40
#endif
.Lhalt:
moveli r41, hw2_last(hv_halt)
shl16insli r41, r41, hw1(hv_halt)
shl16insli r41, r41, hw0(hv_halt)
jalr r41
STD_ENDPROC(relocate_new_kernel)
.section .rodata,"a"
.globl relocate_new_kernel_size
relocate_new_kernel_size:
.long .Lend_relocate_new_kernel - relocate_new_kernel
