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Diffstat (limited to 'arch/tile/kernel/relocate_kernel_64.S')
| -rw-r--r-- | arch/tile/kernel/relocate_kernel_64.S | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/arch/tile/kernel/relocate_kernel_64.S b/arch/tile/kernel/relocate_kernel_64.S new file mode 100644 index 00000000000..1c09a4f5a4e --- /dev/null +++ b/arch/tile/kernel/relocate_kernel_64.S @@ -0,0 +1,260 @@ +/* + * 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) */ + + moveli r40, hw2_last(hv_console_putc) + shl16insli r40, r40, hw1(hv_console_putc) + shl16insli r40, r40, hw0(hv_console_putc) + +#ifdef RELOCATE_NEW_KERNEL_VERBOSE + 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 + +#if CHIP_HAS_CBOX_HOME_MAP() + /* + * 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 +#endif + + /* 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 */ + + moveli r0, '?' + jalr r40 + moveli r0, '\n' + jalr r40 + + 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: moveli r0, 'e' + jalr r40 + moveli r0, 'r' + jalr r40 + moveli r0, 'r' + jalr r40 + moveli r0, '\n' + jalr r40 +.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 |