linux/arch/sparc64/kernel/head.S
David S. Miller 5642530651 [SPARC64]: Add CONFIG_DEBUG_PAGEALLOC support.
The trick is that we do the kernel linear mapping TLB miss starting
with an instruction sequence like this:

	ba,pt		%xcc, kvmap_load
	 xor		%g2, %g4, %g5

succeeded by an instruction sequence which performs a full page table
walk starting at swapper_pg_dir.

We first take over the trap table from the firmware.  Then, using this
constant PTE generation for the linear mapping area above, we build
the kernel page tables for the linear mapping.

After this is setup, we patch that branch above into a "nop", which
will cause TLB misses to fall through to the full page table walk.

With this, the page unmapping for CONFIG_DEBUG_PAGEALLOC is trivial.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-25 16:46:57 -07:00

548 lines
13 KiB
ArmAsm

/* $Id: head.S,v 1.87 2002/02/09 19:49:31 davem Exp $
* head.S: Initial boot code for the Sparc64 port of Linux.
*
* Copyright (C) 1996,1997 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 1996 David Sitsky (David.Sitsky@anu.edu.au)
* Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
* Copyright (C) 1997 Miguel de Icaza (miguel@nuclecu.unam.mx)
*/
#include <linux/config.h>
#include <linux/version.h>
#include <linux/errno.h>
#include <asm/thread_info.h>
#include <asm/asi.h>
#include <asm/pstate.h>
#include <asm/ptrace.h>
#include <asm/spitfire.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/errno.h>
#include <asm/signal.h>
#include <asm/processor.h>
#include <asm/lsu.h>
#include <asm/dcr.h>
#include <asm/dcu.h>
#include <asm/head.h>
#include <asm/ttable.h>
#include <asm/mmu.h>
/* This section from from _start to sparc64_boot_end should fit into
* 0x0000.0000.0040.4000 to 0x0000.0000.0040.8000 and will be sharing space
* with bootup_user_stack, which is from 0x0000.0000.0040.4000 to
* 0x0000.0000.0040.6000 and empty_bad_page, which is from
* 0x0000.0000.0040.6000 to 0x0000.0000.0040.8000.
*/
.text
.globl start, _start, stext, _stext
_start:
start:
_stext:
stext:
bootup_user_stack:
! 0x0000000000404000
b sparc64_boot
flushw /* Flush register file. */
/* This stuff has to be in sync with SILO and other potential boot loaders
* Fields should be kept upward compatible and whenever any change is made,
* HdrS version should be incremented.
*/
.global root_flags, ram_flags, root_dev
.global sparc_ramdisk_image, sparc_ramdisk_size
.global sparc_ramdisk_image64
.ascii "HdrS"
.word LINUX_VERSION_CODE
/* History:
*
* 0x0300 : Supports being located at other than 0x4000
* 0x0202 : Supports kernel params string
* 0x0201 : Supports reboot_command
*/
.half 0x0301 /* HdrS version */
root_flags:
.half 1
root_dev:
.half 0
ram_flags:
.half 0
sparc_ramdisk_image:
.word 0
sparc_ramdisk_size:
.word 0
.xword reboot_command
.xword bootstr_info
sparc_ramdisk_image64:
.xword 0
.word _end
/* PROM cif handler code address is in %o4. */
sparc64_boot:
1: rd %pc, %g7
set 1b, %g1
cmp %g1, %g7
be,pn %xcc, sparc64_boot_after_remap
mov %o4, %l7
/* We need to remap the kernel. Use position independant
* code to remap us to KERNBASE.
*
* SILO can invoke us with 32-bit address masking enabled,
* so make sure that's clear.
*/
rdpr %pstate, %g1
andn %g1, PSTATE_AM, %g1
wrpr %g1, 0x0, %pstate
ba,a,pt %xcc, 1f
.globl prom_finddev_name, prom_chosen_path
.globl prom_getprop_name, prom_mmu_name
.globl prom_callmethod_name, prom_translate_name
.globl prom_map_name, prom_unmap_name, prom_mmu_ihandle_cache
.globl prom_boot_mapped_pc, prom_boot_mapping_mode
.globl prom_boot_mapping_phys_high, prom_boot_mapping_phys_low
prom_finddev_name:
.asciz "finddevice"
prom_chosen_path:
.asciz "/chosen"
prom_getprop_name:
.asciz "getprop"
prom_mmu_name:
.asciz "mmu"
prom_callmethod_name:
.asciz "call-method"
prom_translate_name:
.asciz "translate"
prom_map_name:
.asciz "map"
prom_unmap_name:
.asciz "unmap"
.align 4
prom_mmu_ihandle_cache:
.word 0
prom_boot_mapped_pc:
.word 0
prom_boot_mapping_mode:
.word 0
.align 8
prom_boot_mapping_phys_high:
.xword 0
prom_boot_mapping_phys_low:
.xword 0
1:
rd %pc, %l0
mov (1b - prom_finddev_name), %l1
mov (1b - prom_chosen_path), %l2
mov (1b - prom_boot_mapped_pc), %l3
sub %l0, %l1, %l1
sub %l0, %l2, %l2
sub %l0, %l3, %l3
stw %l0, [%l3]
sub %sp, (192 + 128), %sp
/* chosen_node = prom_finddevice("/chosen") */
stx %l1, [%sp + 2047 + 128 + 0x00] ! service, "finddevice"
mov 1, %l3
stx %l3, [%sp + 2047 + 128 + 0x08] ! num_args, 1
stx %l3, [%sp + 2047 + 128 + 0x10] ! num_rets, 1
stx %l2, [%sp + 2047 + 128 + 0x18] ! arg1, "/chosen"
stx %g0, [%sp + 2047 + 128 + 0x20] ! ret1
call %l7
add %sp, (2047 + 128), %o0 ! argument array
ldx [%sp + 2047 + 128 + 0x20], %l4 ! chosen device node
mov (1b - prom_getprop_name), %l1
mov (1b - prom_mmu_name), %l2
mov (1b - prom_mmu_ihandle_cache), %l5
sub %l0, %l1, %l1
sub %l0, %l2, %l2
sub %l0, %l5, %l5
/* prom_mmu_ihandle_cache = prom_getint(chosen_node, "mmu") */
stx %l1, [%sp + 2047 + 128 + 0x00] ! service, "getprop"
mov 4, %l3
stx %l3, [%sp + 2047 + 128 + 0x08] ! num_args, 4
mov 1, %l3
stx %l3, [%sp + 2047 + 128 + 0x10] ! num_rets, 1
stx %l4, [%sp + 2047 + 128 + 0x18] ! arg1, chosen_node
stx %l2, [%sp + 2047 + 128 + 0x20] ! arg2, "mmu"
stx %l5, [%sp + 2047 + 128 + 0x28] ! arg3, &prom_mmu_ihandle_cache
mov 4, %l3
stx %l3, [%sp + 2047 + 128 + 0x30] ! arg4, sizeof(arg3)
stx %g0, [%sp + 2047 + 128 + 0x38] ! ret1
call %l7
add %sp, (2047 + 128), %o0 ! argument array
mov (1b - prom_callmethod_name), %l1
mov (1b - prom_translate_name), %l2
sub %l0, %l1, %l1
sub %l0, %l2, %l2
lduw [%l5], %l5 ! prom_mmu_ihandle_cache
stx %l1, [%sp + 2047 + 128 + 0x00] ! service, "call-method"
mov 3, %l3
stx %l3, [%sp + 2047 + 128 + 0x08] ! num_args, 3
mov 5, %l3
stx %l3, [%sp + 2047 + 128 + 0x10] ! num_rets, 5
stx %l2, [%sp + 2047 + 128 + 0x18] ! arg1: "translate"
stx %l5, [%sp + 2047 + 128 + 0x20] ! arg2: prom_mmu_ihandle_cache
srlx %l0, 22, %l3
sllx %l3, 22, %l3
stx %l3, [%sp + 2047 + 128 + 0x28] ! arg3: vaddr, our PC
stx %g0, [%sp + 2047 + 128 + 0x30] ! res1
stx %g0, [%sp + 2047 + 128 + 0x38] ! res2
stx %g0, [%sp + 2047 + 128 + 0x40] ! res3
stx %g0, [%sp + 2047 + 128 + 0x48] ! res4
stx %g0, [%sp + 2047 + 128 + 0x50] ! res5
call %l7
add %sp, (2047 + 128), %o0 ! argument array
ldx [%sp + 2047 + 128 + 0x40], %l1 ! translation mode
mov (1b - prom_boot_mapping_mode), %l4
sub %l0, %l4, %l4
stw %l1, [%l4]
mov (1b - prom_boot_mapping_phys_high), %l4
sub %l0, %l4, %l4
ldx [%sp + 2047 + 128 + 0x48], %l2 ! physaddr high
stx %l2, [%l4 + 0x0]
ldx [%sp + 2047 + 128 + 0x50], %l3 ! physaddr low
stx %l3, [%l4 + 0x8]
/* Leave service as-is, "call-method" */
mov 7, %l3
stx %l3, [%sp + 2047 + 128 + 0x08] ! num_args, 7
mov 1, %l3
stx %l3, [%sp + 2047 + 128 + 0x10] ! num_rets, 1
mov (1b - prom_map_name), %l3
sub %l0, %l3, %l3
stx %l3, [%sp + 2047 + 128 + 0x18] ! arg1: "map"
/* Leave arg2 as-is, prom_mmu_ihandle_cache */
mov -1, %l3
stx %l3, [%sp + 2047 + 128 + 0x28] ! arg3: mode (-1 default)
sethi %hi(8 * 1024 * 1024), %l3
stx %l3, [%sp + 2047 + 128 + 0x30] ! arg4: size (8MB)
sethi %hi(KERNBASE), %l3
stx %l3, [%sp + 2047 + 128 + 0x38] ! arg5: vaddr (KERNBASE)
stx %g0, [%sp + 2047 + 128 + 0x40] ! arg6: empty
mov (1b - prom_boot_mapping_phys_low), %l3
sub %l0, %l3, %l3
ldx [%l3], %l3
stx %l3, [%sp + 2047 + 128 + 0x48] ! arg7: phys addr
call %l7
add %sp, (2047 + 128), %o0 ! argument array
add %sp, (192 + 128), %sp
sparc64_boot_after_remap:
BRANCH_IF_CHEETAH_BASE(g1,g7,cheetah_boot)
BRANCH_IF_CHEETAH_PLUS_OR_FOLLOWON(g1,g7,cheetah_plus_boot)
ba,pt %xcc, spitfire_boot
nop
cheetah_plus_boot:
/* Preserve OBP chosen DCU and DCR register settings. */
ba,pt %xcc, cheetah_generic_boot
nop
cheetah_boot:
mov DCR_BPE | DCR_RPE | DCR_SI | DCR_IFPOE | DCR_MS, %g1
wr %g1, %asr18
sethi %uhi(DCU_ME|DCU_RE|DCU_HPE|DCU_SPE|DCU_SL|DCU_WE), %g7
or %g7, %ulo(DCU_ME|DCU_RE|DCU_HPE|DCU_SPE|DCU_SL|DCU_WE), %g7
sllx %g7, 32, %g7
or %g7, DCU_DM | DCU_IM | DCU_DC | DCU_IC, %g7
stxa %g7, [%g0] ASI_DCU_CONTROL_REG
membar #Sync
cheetah_generic_boot:
mov TSB_EXTENSION_P, %g3
stxa %g0, [%g3] ASI_DMMU
stxa %g0, [%g3] ASI_IMMU
membar #Sync
mov TSB_EXTENSION_S, %g3
stxa %g0, [%g3] ASI_DMMU
membar #Sync
mov TSB_EXTENSION_N, %g3
stxa %g0, [%g3] ASI_DMMU
stxa %g0, [%g3] ASI_IMMU
membar #Sync
ba,a,pt %xcc, jump_to_sun4u_init
spitfire_boot:
/* Typically PROM has already enabled both MMU's and both on-chip
* caches, but we do it here anyway just to be paranoid.
*/
mov (LSU_CONTROL_IC|LSU_CONTROL_DC|LSU_CONTROL_IM|LSU_CONTROL_DM), %g1
stxa %g1, [%g0] ASI_LSU_CONTROL
membar #Sync
jump_to_sun4u_init:
/*
* Make sure we are in privileged mode, have address masking,
* using the ordinary globals and have enabled floating
* point.
*
* Again, typically PROM has left %pil at 13 or similar, and
* (PSTATE_PRIV | PSTATE_PEF | PSTATE_IE) in %pstate.
*/
wrpr %g0, (PSTATE_PRIV|PSTATE_PEF|PSTATE_IE), %pstate
wr %g0, 0, %fprs
set sun4u_init, %g2
jmpl %g2 + %g0, %g0
nop
sun4u_init:
/* Set ctx 0 */
mov PRIMARY_CONTEXT, %g7
stxa %g0, [%g7] ASI_DMMU
membar #Sync
mov SECONDARY_CONTEXT, %g7
stxa %g0, [%g7] ASI_DMMU
membar #Sync
BRANCH_IF_ANY_CHEETAH(g1,g7,cheetah_tlb_fixup)
ba,pt %xcc, spitfire_tlb_fixup
nop
cheetah_tlb_fixup:
mov 2, %g2 /* Set TLB type to cheetah+. */
BRANCH_IF_CHEETAH_PLUS_OR_FOLLOWON(g1,g7,1f)
mov 1, %g2 /* Set TLB type to cheetah. */
1: sethi %hi(tlb_type), %g1
stw %g2, [%g1 + %lo(tlb_type)]
BRANCH_IF_CHEETAH_PLUS_OR_FOLLOWON(g1,g7,1f)
ba,pt %xcc, 2f
nop
1: /* Patch context register writes to support nucleus page
* size correctly.
*/
call cheetah_plus_patch_etrap
nop
call cheetah_plus_patch_rtrap
nop
call cheetah_plus_patch_fpdis
nop
call cheetah_plus_patch_winfixup
nop
2: /* Patch copy/page operations to cheetah optimized versions. */
call cheetah_patch_copyops
nop
call cheetah_patch_copy_page
nop
call cheetah_patch_cachetlbops
nop
ba,pt %xcc, tlb_fixup_done
nop
spitfire_tlb_fixup:
/* Set TLB type to spitfire. */
mov 0, %g2
sethi %hi(tlb_type), %g1
stw %g2, [%g1 + %lo(tlb_type)]
tlb_fixup_done:
sethi %hi(init_thread_union), %g6
or %g6, %lo(init_thread_union), %g6
ldx [%g6 + TI_TASK], %g4
mov %sp, %l6
mov %o4, %l7
wr %g0, ASI_P, %asi
mov 1, %g1
sllx %g1, THREAD_SHIFT, %g1
sub %g1, (STACKFRAME_SZ + STACK_BIAS), %g1
add %g6, %g1, %sp
mov 0, %fp
/* Set per-cpu pointer initially to zero, this makes
* the boot-cpu use the in-kernel-image per-cpu areas
* before setup_per_cpu_area() is invoked.
*/
clr %g5
wrpr %g0, 0, %wstate
wrpr %g0, 0x0, %tl
/* Clear the bss */
sethi %hi(__bss_start), %o0
or %o0, %lo(__bss_start), %o0
sethi %hi(_end), %o1
or %o1, %lo(_end), %o1
call __bzero
sub %o1, %o0, %o1
mov %l6, %o1 ! OpenPROM stack
call prom_init
mov %l7, %o0 ! OpenPROM cif handler
/* Off we go.... */
call start_kernel
nop
/* Not reached... */
/* IMPORTANT NOTE: Whenever making changes here, check
* trampoline.S as well. -jj */
.globl setup_tba
setup_tba: /* i0 = is_starfire */
save %sp, -160, %sp
rdpr %tba, %g7
sethi %hi(prom_tba), %o1
or %o1, %lo(prom_tba), %o1
stx %g7, [%o1]
/* Setup "Linux" globals 8-) */
rdpr %pstate, %o1
mov %g6, %o2
wrpr %o1, (PSTATE_AG|PSTATE_IE), %pstate
sethi %hi(sparc64_ttable_tl0), %g1
wrpr %g1, %tba
mov %o2, %g6
/* Set up MMU globals */
wrpr %o1, (PSTATE_MG|PSTATE_IE), %pstate
/* Set fixed globals used by dTLB miss handler. */
#define KERN_HIGHBITS ((_PAGE_VALID|_PAGE_SZ4MB)^0xfffff80000000000)
#define KERN_LOWBITS (_PAGE_CP | _PAGE_CV | _PAGE_P | _PAGE_W)
mov TSB_REG, %g1
stxa %g0, [%g1] ASI_DMMU
membar #Sync
stxa %g0, [%g1] ASI_IMMU
membar #Sync
mov TLB_SFSR, %g1
sethi %uhi(KERN_HIGHBITS), %g2
or %g2, %ulo(KERN_HIGHBITS), %g2
sllx %g2, 32, %g2
or %g2, KERN_LOWBITS, %g2
BRANCH_IF_ANY_CHEETAH(g3,g7,cheetah_vpte_base)
ba,pt %xcc, spitfire_vpte_base
nop
cheetah_vpte_base:
sethi %uhi(VPTE_BASE_CHEETAH), %g3
or %g3, %ulo(VPTE_BASE_CHEETAH), %g3
ba,pt %xcc, 2f
sllx %g3, 32, %g3
spitfire_vpte_base:
sethi %uhi(VPTE_BASE_SPITFIRE), %g3
or %g3, %ulo(VPTE_BASE_SPITFIRE), %g3
sllx %g3, 32, %g3
2:
clr %g7
#undef KERN_HIGHBITS
#undef KERN_LOWBITS
/* Kill PROM timer */
sethi %hi(0x80000000), %o2
sllx %o2, 32, %o2
wr %o2, 0, %tick_cmpr
BRANCH_IF_ANY_CHEETAH(o2,o3,1f)
ba,pt %xcc, 2f
nop
/* Disable STICK_INT interrupts. */
1:
sethi %hi(0x80000000), %o2
sllx %o2, 32, %o2
wr %o2, %asr25
/* Ok, we're done setting up all the state our trap mechanims needs,
* now get back into normal globals and let the PROM know what is up.
*/
2:
wrpr %g0, %g0, %wstate
wrpr %o1, PSTATE_IE, %pstate
call init_irqwork_curcpu
nop
call prom_set_trap_table
sethi %hi(sparc64_ttable_tl0), %o0
BRANCH_IF_CHEETAH_PLUS_OR_FOLLOWON(g2,g3,1f)
ba,pt %xcc, 2f
nop
1: /* Start using proper page size encodings in ctx register. */
sethi %uhi(CTX_CHEETAH_PLUS_NUC), %g3
mov PRIMARY_CONTEXT, %g1
sllx %g3, 32, %g3
sethi %hi(CTX_CHEETAH_PLUS_CTX0), %g2
or %g3, %g2, %g3
stxa %g3, [%g1] ASI_DMMU
membar #Sync
2:
rdpr %pstate, %o1
or %o1, PSTATE_IE, %o1
wrpr %o1, 0, %pstate
ret
restore
/*
* The following skips make sure the trap table in ttable.S is aligned
* on a 32K boundary as required by the v9 specs for TBA register.
*/
sparc64_boot_end:
.skip 0x2000 + _start - sparc64_boot_end
bootup_user_stack_end:
.skip 0x2000
#ifdef CONFIG_SBUS
/* This is just a hack to fool make depend config.h discovering
strategy: As the .S files below need config.h, but
make depend does not find it for them, we include config.h
in head.S */
#endif
! 0x0000000000408000
#include "ttable.S"
#include "systbls.S"
#include "ktlb.S"
#include "etrap.S"
#include "rtrap.S"
#include "winfixup.S"
#include "entry.S"
/* This is just anal retentiveness on my part... */
.align 16384
.data
.align 8
.globl prom_tba, tlb_type
prom_tba: .xword 0
tlb_type: .word 0 /* Must NOT end up in BSS */
.section ".fixup",#alloc,#execinstr
.globl __ret_efault
__ret_efault:
ret
restore %g0, -EFAULT, %o0