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-rw-r--r--arch/tile/kernel/relocate_kernel.S280
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diff --git a/arch/tile/kernel/relocate_kernel.S b/arch/tile/kernel/relocate_kernel.S
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+/*
+ * Copyright 2010 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>
+
+#define ___hvb MEM_SV_INTRPT + HV_GLUE_START_CPA
+
+#define ___hv_dispatch(f) (___hvb + (HV_DISPATCH_ENTRY_SIZE * f))
+
+#define ___hv_console_putc ___hv_dispatch(HV_DISPATCH_CONSOLE_PUTC)
+#define ___hv_halt ___hv_dispatch(HV_DISPATCH_HALT)
+#define ___hv_reexec ___hv_dispatch(HV_DISPATCH_REEXEC)
+#define ___hv_flush_remote ___hv_dispatch(HV_DISPATCH_FLUSH_REMOTE)
+
+#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 */
+
+ shri 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, lo16(___hv_console_putc)
+ auli r40, r40, ha16(___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 four. 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.
+ */
+
+ sw sp, r30
+ move r30, sp
+ addi sp, sp, -8
+
+#if CHIP_HAS_CBOX_HOME_MAP()
+ /*
+ * On TILEPro, 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 */
+ move r1, zero
+ }
+ {
+ auli r2, zero, ha16(HV_FLUSH_EVICT_L2) /* cache_control */
+ movei r3, -1 /* cache_cpumask; -1 means all client tiles */
+ }
+ {
+ move r4, zero /* tlb_va */
+ move r5, zero /* tlb_length */
+ }
+ {
+ move r6, zero /* tlb_pgsize */
+ move r7, zero /* tlb_cpumask */
+ }
+ {
+ move r8, zero /* asids */
+ moveli r20, lo16(___hv_flush_remote)
+ }
+ {
+ move r9, zero /* asidcount */
+ auli r20, r20, ha16(___hv_flush_remote)
+ }
+
+ jalr r20
+#endif
+
+ /* r33 is destination pointer, default to zero */
+
+ moveli r33, 0
+
+.Lloop: lw 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 */
+
+ seqi r0, r9, 0x1 /* IND_DESTINATION */
+ bzt r0, .Ltry2
+
+ move r33, r10
+
+#ifdef RELOCATE_NEW_KERNEL_VERBOSE
+ moveli r0, 'd'
+ jalr r40
+#endif
+
+ addi r30, r30, 4
+ j .Lloop
+
+.Ltry2:
+ seqi r0, r9, 0x2 /* IND_INDIRECTION */
+ bzt r0, .Ltry4
+
+ move r30, r10
+
+#ifdef RELOCATE_NEW_KERNEL_VERBOSE
+ moveli r0, 'i'
+ jalr r40
+#endif
+
+ j .Lloop
+
+.Ltry4:
+ seqi r0, r9, 0x4 /* IND_DONE */
+ bzt r0, .Ltry8
+
+ mf
+
+#ifdef RELOCATE_NEW_KERNEL_VERBOSE
+ moveli r0, 'D'
+ jalr r40
+ moveli r0, '\n'
+ jalr r40
+#endif
+
+ move r0, r32
+ moveli r1, 0 /* arg to hv_reexec is 64 bits */
+
+ moveli r41, lo16(___hv_reexec)
+ auli r41, r41, ha16(___hv_reexec)
+
+ jalr r41
+
+ /* we should not get here */
+
+ moveli r0, '?'
+ jalr r40
+ moveli r0, '\n'
+ jalr r40
+
+ j .Lhalt
+
+.Ltry8: seqi r0, r9, 0x8 /* IND_SOURCE */
+ bz r0, .Lerr /* unknown type */
+
+ /* copy page at r10 to page at r33 */
+
+ move r11, r33
+
+ moveli r0, lo16(PAGE_SIZE)
+ auli r0, r0, ha16(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 16, so we can unroll
+ * 16 times safely without any edge case checking.
+ *
+ * Issue a flush of the destination every 16 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:
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0; addi r11, r11, 4 }
+ { lw r0, r10; addi r10, r10, 4 }
+ { sw r11, r0 }
+ { flush r11 ; addi r11, r11, 4 }
+
+ seq r0, r33, r11
+ bzt r0, 1b
+
+#ifdef RELOCATE_NEW_KERNEL_VERBOSE
+ moveli r0, 's'
+ jalr r40
+#endif
+
+ addi r30, r30, 4
+ 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, lo16(___hv_halt)
+ auli r41, r41, ha16(___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