1333 строки
36 KiB
ArmAsm
1333 строки
36 KiB
ArmAsm
/*
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* PowerPC version
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* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
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*
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* Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP
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* Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
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* Adapted for Power Macintosh by Paul Mackerras.
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* Low-level exception handlers and MMU support
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* rewritten by Paul Mackerras.
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* Copyright (C) 1996 Paul Mackerras.
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* MPC8xx modifications Copyright (C) 1997 Dan Malek (dmalek@jlc.net).
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*
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* This file contains the low-level support and setup for the
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* PowerPC platform, including trap and interrupt dispatch.
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* (The PPC 8xx embedded CPUs use head_8xx.S instead.)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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*/
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#include <asm/reg.h>
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#include <asm/page.h>
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#include <asm/mmu.h>
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#include <asm/pgtable.h>
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#include <asm/cputable.h>
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#include <asm/cache.h>
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#include <asm/thread_info.h>
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#include <asm/ppc_asm.h>
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#include <asm/asm-offsets.h>
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#include <asm/ptrace.h>
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#include <asm/bug.h>
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/* 601 only have IBAT; cr0.eq is set on 601 when using this macro */
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#define LOAD_BAT(n, reg, RA, RB) \
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/* see the comment for clear_bats() -- Cort */ \
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li RA,0; \
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mtspr SPRN_IBAT##n##U,RA; \
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mtspr SPRN_DBAT##n##U,RA; \
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lwz RA,(n*16)+0(reg); \
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lwz RB,(n*16)+4(reg); \
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mtspr SPRN_IBAT##n##U,RA; \
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mtspr SPRN_IBAT##n##L,RB; \
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beq 1f; \
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lwz RA,(n*16)+8(reg); \
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lwz RB,(n*16)+12(reg); \
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mtspr SPRN_DBAT##n##U,RA; \
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mtspr SPRN_DBAT##n##L,RB; \
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1:
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.section .text.head, "ax"
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.stabs "arch/powerpc/kernel/",N_SO,0,0,0f
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.stabs "head_32.S",N_SO,0,0,0f
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0:
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_ENTRY(_stext);
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/*
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* _start is defined this way because the XCOFF loader in the OpenFirmware
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* on the powermac expects the entry point to be a procedure descriptor.
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*/
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_ENTRY(_start);
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/*
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* These are here for legacy reasons, the kernel used to
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* need to look like a coff function entry for the pmac
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* but we're always started by some kind of bootloader now.
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* -- Cort
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*/
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nop /* used by __secondary_hold on prep (mtx) and chrp smp */
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nop /* used by __secondary_hold on prep (mtx) and chrp smp */
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nop
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/* PMAC
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* Enter here with the kernel text, data and bss loaded starting at
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* 0, running with virtual == physical mapping.
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* r5 points to the prom entry point (the client interface handler
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* address). Address translation is turned on, with the prom
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* managing the hash table. Interrupts are disabled. The stack
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* pointer (r1) points to just below the end of the half-meg region
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* from 0x380000 - 0x400000, which is mapped in already.
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*
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* If we are booted from MacOS via BootX, we enter with the kernel
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* image loaded somewhere, and the following values in registers:
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* r3: 'BooX' (0x426f6f58)
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* r4: virtual address of boot_infos_t
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* r5: 0
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*
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* PREP
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* This is jumped to on prep systems right after the kernel is relocated
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* to its proper place in memory by the boot loader. The expected layout
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* of the regs is:
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* r3: ptr to residual data
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* r4: initrd_start or if no initrd then 0
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* r5: initrd_end - unused if r4 is 0
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* r6: Start of command line string
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* r7: End of command line string
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*
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* This just gets a minimal mmu environment setup so we can call
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* start_here() to do the real work.
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* -- Cort
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*/
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.globl __start
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__start:
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/*
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* We have to do any OF calls before we map ourselves to KERNELBASE,
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* because OF may have I/O devices mapped into that area
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* (particularly on CHRP).
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*/
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#ifdef CONFIG_PPC_MULTIPLATFORM
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cmpwi 0,r5,0
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beq 1f
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/* find out where we are now */
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bcl 20,31,$+4
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0: mflr r8 /* r8 = runtime addr here */
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addis r8,r8,(_stext - 0b)@ha
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addi r8,r8,(_stext - 0b)@l /* current runtime base addr */
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bl prom_init
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trap
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#endif
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/*
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* Check for BootX signature when supporting PowerMac and branch to
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* appropriate trampoline if it's present
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*/
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#ifdef CONFIG_PPC_PMAC
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1: lis r31,0x426f
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ori r31,r31,0x6f58
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cmpw 0,r3,r31
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bne 1f
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bl bootx_init
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trap
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#endif /* CONFIG_PPC_PMAC */
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1: mr r31,r3 /* save parameters */
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mr r30,r4
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li r24,0 /* cpu # */
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/*
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* early_init() does the early machine identification and does
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* the necessary low-level setup and clears the BSS
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* -- Cort <cort@fsmlabs.com>
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*/
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bl early_init
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/* Switch MMU off, clear BATs and flush TLB. At this point, r3 contains
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* the physical address we are running at, returned by early_init()
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*/
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bl mmu_off
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__after_mmu_off:
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bl clear_bats
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bl flush_tlbs
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bl initial_bats
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#if defined(CONFIG_BOOTX_TEXT)
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bl setup_disp_bat
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#endif
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#ifdef CONFIG_PPC_EARLY_DEBUG_CPM
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bl setup_cpm_bat
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#endif
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/*
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* Call setup_cpu for CPU 0 and initialize 6xx Idle
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*/
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bl reloc_offset
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li r24,0 /* cpu# */
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bl call_setup_cpu /* Call setup_cpu for this CPU */
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#ifdef CONFIG_6xx
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bl reloc_offset
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bl init_idle_6xx
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#endif /* CONFIG_6xx */
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/*
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* We need to run with _start at physical address 0.
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* On CHRP, we are loaded at 0x10000 since OF on CHRP uses
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* the exception vectors at 0 (and therefore this copy
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* overwrites OF's exception vectors with our own).
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* The MMU is off at this point.
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*/
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bl reloc_offset
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mr r26,r3
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addis r4,r3,KERNELBASE@h /* current address of _start */
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lis r5,PHYSICAL_START@h
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cmplw 0,r4,r5 /* already running at PHYSICAL_START? */
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bne relocate_kernel
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/*
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* we now have the 1st 16M of ram mapped with the bats.
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* prep needs the mmu to be turned on here, but pmac already has it on.
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* this shouldn't bother the pmac since it just gets turned on again
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* as we jump to our code at KERNELBASE. -- Cort
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* Actually no, pmac doesn't have it on any more. BootX enters with MMU
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* off, and in other cases, we now turn it off before changing BATs above.
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*/
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turn_on_mmu:
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mfmsr r0
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ori r0,r0,MSR_DR|MSR_IR
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mtspr SPRN_SRR1,r0
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lis r0,start_here@h
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ori r0,r0,start_here@l
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mtspr SPRN_SRR0,r0
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SYNC
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RFI /* enables MMU */
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/*
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* We need __secondary_hold as a place to hold the other cpus on
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* an SMP machine, even when we are running a UP kernel.
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*/
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. = 0xc0 /* for prep bootloader */
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li r3,1 /* MTX only has 1 cpu */
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.globl __secondary_hold
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__secondary_hold:
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/* tell the master we're here */
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stw r3,__secondary_hold_acknowledge@l(0)
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#ifdef CONFIG_SMP
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100: lwz r4,0(0)
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/* wait until we're told to start */
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cmpw 0,r4,r3
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bne 100b
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/* our cpu # was at addr 0 - go */
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mr r24,r3 /* cpu # */
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b __secondary_start
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#else
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b .
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#endif /* CONFIG_SMP */
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.globl __secondary_hold_spinloop
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__secondary_hold_spinloop:
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.long 0
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.globl __secondary_hold_acknowledge
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__secondary_hold_acknowledge:
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.long -1
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/*
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* Exception entry code. This code runs with address translation
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* turned off, i.e. using physical addresses.
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* We assume sprg3 has the physical address of the current
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* task's thread_struct.
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*/
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#define EXCEPTION_PROLOG \
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mtspr SPRN_SPRG0,r10; \
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mtspr SPRN_SPRG1,r11; \
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mfcr r10; \
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EXCEPTION_PROLOG_1; \
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EXCEPTION_PROLOG_2
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#define EXCEPTION_PROLOG_1 \
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mfspr r11,SPRN_SRR1; /* check whether user or kernel */ \
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andi. r11,r11,MSR_PR; \
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tophys(r11,r1); /* use tophys(r1) if kernel */ \
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beq 1f; \
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mfspr r11,SPRN_SPRG3; \
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lwz r11,THREAD_INFO-THREAD(r11); \
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addi r11,r11,THREAD_SIZE; \
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tophys(r11,r11); \
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1: subi r11,r11,INT_FRAME_SIZE /* alloc exc. frame */
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#define EXCEPTION_PROLOG_2 \
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CLR_TOP32(r11); \
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stw r10,_CCR(r11); /* save registers */ \
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stw r12,GPR12(r11); \
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stw r9,GPR9(r11); \
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mfspr r10,SPRN_SPRG0; \
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stw r10,GPR10(r11); \
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mfspr r12,SPRN_SPRG1; \
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stw r12,GPR11(r11); \
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mflr r10; \
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stw r10,_LINK(r11); \
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mfspr r12,SPRN_SRR0; \
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mfspr r9,SPRN_SRR1; \
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stw r1,GPR1(r11); \
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stw r1,0(r11); \
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tovirt(r1,r11); /* set new kernel sp */ \
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li r10,MSR_KERNEL & ~(MSR_IR|MSR_DR); /* can take exceptions */ \
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MTMSRD(r10); /* (except for mach check in rtas) */ \
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stw r0,GPR0(r11); \
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lis r10,STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */ \
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addi r10,r10,STACK_FRAME_REGS_MARKER@l; \
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stw r10,8(r11); \
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SAVE_4GPRS(3, r11); \
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SAVE_2GPRS(7, r11)
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/*
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* Note: code which follows this uses cr0.eq (set if from kernel),
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* r11, r12 (SRR0), and r9 (SRR1).
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*
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* Note2: once we have set r1 we are in a position to take exceptions
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* again, and we could thus set MSR:RI at that point.
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*/
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/*
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* Exception vectors.
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*/
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#define EXCEPTION(n, label, hdlr, xfer) \
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. = n; \
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label: \
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EXCEPTION_PROLOG; \
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addi r3,r1,STACK_FRAME_OVERHEAD; \
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xfer(n, hdlr)
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#define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret) \
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li r10,trap; \
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stw r10,_TRAP(r11); \
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li r10,MSR_KERNEL; \
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copyee(r10, r9); \
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bl tfer; \
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i##n: \
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.long hdlr; \
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.long ret
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#define COPY_EE(d, s) rlwimi d,s,0,16,16
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#define NOCOPY(d, s)
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#define EXC_XFER_STD(n, hdlr) \
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EXC_XFER_TEMPLATE(n, hdlr, n, NOCOPY, transfer_to_handler_full, \
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ret_from_except_full)
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#define EXC_XFER_LITE(n, hdlr) \
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EXC_XFER_TEMPLATE(n, hdlr, n+1, NOCOPY, transfer_to_handler, \
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ret_from_except)
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#define EXC_XFER_EE(n, hdlr) \
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EXC_XFER_TEMPLATE(n, hdlr, n, COPY_EE, transfer_to_handler_full, \
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ret_from_except_full)
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#define EXC_XFER_EE_LITE(n, hdlr) \
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EXC_XFER_TEMPLATE(n, hdlr, n+1, COPY_EE, transfer_to_handler, \
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ret_from_except)
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/* System reset */
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/* core99 pmac starts the seconary here by changing the vector, and
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putting it back to what it was (unknown_exception) when done. */
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EXCEPTION(0x100, Reset, unknown_exception, EXC_XFER_STD)
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/* Machine check */
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/*
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* On CHRP, this is complicated by the fact that we could get a
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* machine check inside RTAS, and we have no guarantee that certain
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* critical registers will have the values we expect. The set of
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* registers that might have bad values includes all the GPRs
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* and all the BATs. We indicate that we are in RTAS by putting
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* a non-zero value, the address of the exception frame to use,
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* in SPRG2. The machine check handler checks SPRG2 and uses its
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* value if it is non-zero. If we ever needed to free up SPRG2,
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* we could use a field in the thread_info or thread_struct instead.
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* (Other exception handlers assume that r1 is a valid kernel stack
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* pointer when we take an exception from supervisor mode.)
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* -- paulus.
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*/
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. = 0x200
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mtspr SPRN_SPRG0,r10
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mtspr SPRN_SPRG1,r11
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mfcr r10
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#ifdef CONFIG_PPC_CHRP
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mfspr r11,SPRN_SPRG2
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cmpwi 0,r11,0
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bne 7f
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#endif /* CONFIG_PPC_CHRP */
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EXCEPTION_PROLOG_1
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7: EXCEPTION_PROLOG_2
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addi r3,r1,STACK_FRAME_OVERHEAD
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#ifdef CONFIG_PPC_CHRP
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mfspr r4,SPRN_SPRG2
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cmpwi cr1,r4,0
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bne cr1,1f
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#endif
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EXC_XFER_STD(0x200, machine_check_exception)
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#ifdef CONFIG_PPC_CHRP
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1: b machine_check_in_rtas
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#endif
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/* Data access exception. */
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. = 0x300
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DataAccess:
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EXCEPTION_PROLOG
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mfspr r10,SPRN_DSISR
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stw r10,_DSISR(r11)
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andis. r0,r10,0xa470 /* weird error? */
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bne 1f /* if not, try to put a PTE */
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mfspr r4,SPRN_DAR /* into the hash table */
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rlwinm r3,r10,32-15,21,21 /* DSISR_STORE -> _PAGE_RW */
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bl hash_page
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1: lwz r5,_DSISR(r11) /* get DSISR value */
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mfspr r4,SPRN_DAR
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EXC_XFER_EE_LITE(0x300, handle_page_fault)
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/* Instruction access exception. */
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. = 0x400
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InstructionAccess:
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EXCEPTION_PROLOG
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andis. r0,r9,0x4000 /* no pte found? */
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beq 1f /* if so, try to put a PTE */
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li r3,0 /* into the hash table */
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mr r4,r12 /* SRR0 is fault address */
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bl hash_page
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1: mr r4,r12
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mr r5,r9
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EXC_XFER_EE_LITE(0x400, handle_page_fault)
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/* External interrupt */
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EXCEPTION(0x500, HardwareInterrupt, do_IRQ, EXC_XFER_LITE)
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/* Alignment exception */
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. = 0x600
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Alignment:
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EXCEPTION_PROLOG
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mfspr r4,SPRN_DAR
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stw r4,_DAR(r11)
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mfspr r5,SPRN_DSISR
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stw r5,_DSISR(r11)
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addi r3,r1,STACK_FRAME_OVERHEAD
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EXC_XFER_EE(0x600, alignment_exception)
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/* Program check exception */
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EXCEPTION(0x700, ProgramCheck, program_check_exception, EXC_XFER_STD)
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/* Floating-point unavailable */
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. = 0x800
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FPUnavailable:
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BEGIN_FTR_SECTION
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/*
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* Certain Freescale cores don't have a FPU and treat fp instructions
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* as a FP Unavailable exception. Redirect to illegal/emulation handling.
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*/
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b ProgramCheck
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END_FTR_SECTION_IFSET(CPU_FTR_FPU_UNAVAILABLE)
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EXCEPTION_PROLOG
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beq 1f
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bl load_up_fpu /* if from user, just load it up */
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b fast_exception_return
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1: addi r3,r1,STACK_FRAME_OVERHEAD
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EXC_XFER_EE_LITE(0x800, kernel_fp_unavailable_exception)
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/* Decrementer */
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EXCEPTION(0x900, Decrementer, timer_interrupt, EXC_XFER_LITE)
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EXCEPTION(0xa00, Trap_0a, unknown_exception, EXC_XFER_EE)
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EXCEPTION(0xb00, Trap_0b, unknown_exception, EXC_XFER_EE)
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/* System call */
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. = 0xc00
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SystemCall:
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EXCEPTION_PROLOG
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EXC_XFER_EE_LITE(0xc00, DoSyscall)
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/* Single step - not used on 601 */
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EXCEPTION(0xd00, SingleStep, single_step_exception, EXC_XFER_STD)
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EXCEPTION(0xe00, Trap_0e, unknown_exception, EXC_XFER_EE)
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/*
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* The Altivec unavailable trap is at 0x0f20. Foo.
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* We effectively remap it to 0x3000.
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* We include an altivec unavailable exception vector even if
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* not configured for Altivec, so that you can't panic a
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* non-altivec kernel running on a machine with altivec just
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* by executing an altivec instruction.
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*/
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. = 0xf00
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b PerformanceMonitor
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. = 0xf20
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b AltiVecUnavailable
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/*
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* Handle TLB miss for instruction on 603/603e.
|
|
* Note: we get an alternate set of r0 - r3 to use automatically.
|
|
*/
|
|
. = 0x1000
|
|
InstructionTLBMiss:
|
|
/*
|
|
* r0: stored ctr
|
|
* r1: linux style pte ( later becomes ppc hardware pte )
|
|
* r2: ptr to linux-style pte
|
|
* r3: scratch
|
|
*/
|
|
mfctr r0
|
|
/* Get PTE (linux-style) and check access */
|
|
mfspr r3,SPRN_IMISS
|
|
lis r1,PAGE_OFFSET@h /* check if kernel address */
|
|
cmplw 0,r1,r3
|
|
mfspr r2,SPRN_SPRG3
|
|
li r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
|
|
lwz r2,PGDIR(r2)
|
|
bge- 112f
|
|
mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
|
|
rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
|
|
lis r2,swapper_pg_dir@ha /* if kernel address, use */
|
|
addi r2,r2,swapper_pg_dir@l /* kernel page table */
|
|
112: tophys(r2,r2)
|
|
rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
|
|
lwz r2,0(r2) /* get pmd entry */
|
|
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
|
|
beq- InstructionAddressInvalid /* return if no mapping */
|
|
rlwimi r2,r3,22,20,29 /* insert next 10 bits of address */
|
|
lwz r3,0(r2) /* get linux-style pte */
|
|
andc. r1,r1,r3 /* check access & ~permission */
|
|
bne- InstructionAddressInvalid /* return if access not permitted */
|
|
ori r3,r3,_PAGE_ACCESSED /* set _PAGE_ACCESSED in pte */
|
|
/*
|
|
* NOTE! We are assuming this is not an SMP system, otherwise
|
|
* we would need to update the pte atomically with lwarx/stwcx.
|
|
*/
|
|
stw r3,0(r2) /* update PTE (accessed bit) */
|
|
/* Convert linux-style PTE to low word of PPC-style PTE */
|
|
rlwinm r1,r3,32-10,31,31 /* _PAGE_RW -> PP lsb */
|
|
rlwinm r2,r3,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */
|
|
and r1,r1,r2 /* writable if _RW and _DIRTY */
|
|
rlwimi r3,r3,32-1,30,30 /* _PAGE_USER -> PP msb */
|
|
rlwimi r3,r3,32-1,31,31 /* _PAGE_USER -> PP lsb */
|
|
ori r1,r1,0xe14 /* clear out reserved bits and M */
|
|
andc r1,r3,r1 /* PP = user? (rw&dirty? 2: 3): 0 */
|
|
mtspr SPRN_RPA,r1
|
|
mfspr r3,SPRN_IMISS
|
|
tlbli r3
|
|
mfspr r3,SPRN_SRR1 /* Need to restore CR0 */
|
|
mtcrf 0x80,r3
|
|
rfi
|
|
InstructionAddressInvalid:
|
|
mfspr r3,SPRN_SRR1
|
|
rlwinm r1,r3,9,6,6 /* Get load/store bit */
|
|
|
|
addis r1,r1,0x2000
|
|
mtspr SPRN_DSISR,r1 /* (shouldn't be needed) */
|
|
mtctr r0 /* Restore CTR */
|
|
andi. r2,r3,0xFFFF /* Clear upper bits of SRR1 */
|
|
or r2,r2,r1
|
|
mtspr SPRN_SRR1,r2
|
|
mfspr r1,SPRN_IMISS /* Get failing address */
|
|
rlwinm. r2,r2,0,31,31 /* Check for little endian access */
|
|
rlwimi r2,r2,1,30,30 /* change 1 -> 3 */
|
|
xor r1,r1,r2
|
|
mtspr SPRN_DAR,r1 /* Set fault address */
|
|
mfmsr r0 /* Restore "normal" registers */
|
|
xoris r0,r0,MSR_TGPR>>16
|
|
mtcrf 0x80,r3 /* Restore CR0 */
|
|
mtmsr r0
|
|
b InstructionAccess
|
|
|
|
/*
|
|
* Handle TLB miss for DATA Load operation on 603/603e
|
|
*/
|
|
. = 0x1100
|
|
DataLoadTLBMiss:
|
|
/*
|
|
* r0: stored ctr
|
|
* r1: linux style pte ( later becomes ppc hardware pte )
|
|
* r2: ptr to linux-style pte
|
|
* r3: scratch
|
|
*/
|
|
mfctr r0
|
|
/* Get PTE (linux-style) and check access */
|
|
mfspr r3,SPRN_DMISS
|
|
lis r1,PAGE_OFFSET@h /* check if kernel address */
|
|
cmplw 0,r1,r3
|
|
mfspr r2,SPRN_SPRG3
|
|
li r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
|
|
lwz r2,PGDIR(r2)
|
|
bge- 112f
|
|
mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
|
|
rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
|
|
lis r2,swapper_pg_dir@ha /* if kernel address, use */
|
|
addi r2,r2,swapper_pg_dir@l /* kernel page table */
|
|
112: tophys(r2,r2)
|
|
rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
|
|
lwz r2,0(r2) /* get pmd entry */
|
|
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
|
|
beq- DataAddressInvalid /* return if no mapping */
|
|
rlwimi r2,r3,22,20,29 /* insert next 10 bits of address */
|
|
lwz r3,0(r2) /* get linux-style pte */
|
|
andc. r1,r1,r3 /* check access & ~permission */
|
|
bne- DataAddressInvalid /* return if access not permitted */
|
|
ori r3,r3,_PAGE_ACCESSED /* set _PAGE_ACCESSED in pte */
|
|
/*
|
|
* NOTE! We are assuming this is not an SMP system, otherwise
|
|
* we would need to update the pte atomically with lwarx/stwcx.
|
|
*/
|
|
stw r3,0(r2) /* update PTE (accessed bit) */
|
|
/* Convert linux-style PTE to low word of PPC-style PTE */
|
|
rlwinm r1,r3,32-10,31,31 /* _PAGE_RW -> PP lsb */
|
|
rlwinm r2,r3,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */
|
|
and r1,r1,r2 /* writable if _RW and _DIRTY */
|
|
rlwimi r3,r3,32-1,30,30 /* _PAGE_USER -> PP msb */
|
|
rlwimi r3,r3,32-1,31,31 /* _PAGE_USER -> PP lsb */
|
|
ori r1,r1,0xe14 /* clear out reserved bits and M */
|
|
andc r1,r3,r1 /* PP = user? (rw&dirty? 2: 3): 0 */
|
|
mtspr SPRN_RPA,r1
|
|
mfspr r3,SPRN_DMISS
|
|
tlbld r3
|
|
mfspr r3,SPRN_SRR1 /* Need to restore CR0 */
|
|
mtcrf 0x80,r3
|
|
rfi
|
|
DataAddressInvalid:
|
|
mfspr r3,SPRN_SRR1
|
|
rlwinm r1,r3,9,6,6 /* Get load/store bit */
|
|
addis r1,r1,0x2000
|
|
mtspr SPRN_DSISR,r1
|
|
mtctr r0 /* Restore CTR */
|
|
andi. r2,r3,0xFFFF /* Clear upper bits of SRR1 */
|
|
mtspr SPRN_SRR1,r2
|
|
mfspr r1,SPRN_DMISS /* Get failing address */
|
|
rlwinm. r2,r2,0,31,31 /* Check for little endian access */
|
|
beq 20f /* Jump if big endian */
|
|
xori r1,r1,3
|
|
20: mtspr SPRN_DAR,r1 /* Set fault address */
|
|
mfmsr r0 /* Restore "normal" registers */
|
|
xoris r0,r0,MSR_TGPR>>16
|
|
mtcrf 0x80,r3 /* Restore CR0 */
|
|
mtmsr r0
|
|
b DataAccess
|
|
|
|
/*
|
|
* Handle TLB miss for DATA Store on 603/603e
|
|
*/
|
|
. = 0x1200
|
|
DataStoreTLBMiss:
|
|
/*
|
|
* r0: stored ctr
|
|
* r1: linux style pte ( later becomes ppc hardware pte )
|
|
* r2: ptr to linux-style pte
|
|
* r3: scratch
|
|
*/
|
|
mfctr r0
|
|
/* Get PTE (linux-style) and check access */
|
|
mfspr r3,SPRN_DMISS
|
|
lis r1,PAGE_OFFSET@h /* check if kernel address */
|
|
cmplw 0,r1,r3
|
|
mfspr r2,SPRN_SPRG3
|
|
li r1,_PAGE_RW|_PAGE_USER|_PAGE_PRESENT /* access flags */
|
|
lwz r2,PGDIR(r2)
|
|
bge- 112f
|
|
mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
|
|
rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
|
|
lis r2,swapper_pg_dir@ha /* if kernel address, use */
|
|
addi r2,r2,swapper_pg_dir@l /* kernel page table */
|
|
112: tophys(r2,r2)
|
|
rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
|
|
lwz r2,0(r2) /* get pmd entry */
|
|
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
|
|
beq- DataAddressInvalid /* return if no mapping */
|
|
rlwimi r2,r3,22,20,29 /* insert next 10 bits of address */
|
|
lwz r3,0(r2) /* get linux-style pte */
|
|
andc. r1,r1,r3 /* check access & ~permission */
|
|
bne- DataAddressInvalid /* return if access not permitted */
|
|
ori r3,r3,_PAGE_ACCESSED|_PAGE_DIRTY
|
|
/*
|
|
* NOTE! We are assuming this is not an SMP system, otherwise
|
|
* we would need to update the pte atomically with lwarx/stwcx.
|
|
*/
|
|
stw r3,0(r2) /* update PTE (accessed/dirty bits) */
|
|
/* Convert linux-style PTE to low word of PPC-style PTE */
|
|
rlwimi r3,r3,32-1,30,30 /* _PAGE_USER -> PP msb */
|
|
li r1,0xe15 /* clear out reserved bits and M */
|
|
andc r1,r3,r1 /* PP = user? 2: 0 */
|
|
mtspr SPRN_RPA,r1
|
|
mfspr r3,SPRN_DMISS
|
|
tlbld r3
|
|
mfspr r3,SPRN_SRR1 /* Need to restore CR0 */
|
|
mtcrf 0x80,r3
|
|
rfi
|
|
|
|
#ifndef CONFIG_ALTIVEC
|
|
#define altivec_assist_exception unknown_exception
|
|
#endif
|
|
|
|
EXCEPTION(0x1300, Trap_13, instruction_breakpoint_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x1400, SMI, SMIException, EXC_XFER_EE)
|
|
EXCEPTION(0x1500, Trap_15, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x1600, Trap_16, altivec_assist_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x1700, Trap_17, TAUException, EXC_XFER_STD)
|
|
EXCEPTION(0x1800, Trap_18, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x1900, Trap_19, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x1a00, Trap_1a, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x1b00, Trap_1b, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x1c00, Trap_1c, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x1d00, Trap_1d, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x1e00, Trap_1e, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x1f00, Trap_1f, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2000, RunMode, RunModeException, EXC_XFER_EE)
|
|
EXCEPTION(0x2100, Trap_21, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2200, Trap_22, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2300, Trap_23, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2400, Trap_24, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2500, Trap_25, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2600, Trap_26, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2700, Trap_27, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2800, Trap_28, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2900, Trap_29, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2a00, Trap_2a, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2b00, Trap_2b, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2c00, Trap_2c, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2d00, Trap_2d, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2e00, Trap_2e, unknown_exception, EXC_XFER_EE)
|
|
EXCEPTION(0x2f00, MOLTrampoline, unknown_exception, EXC_XFER_EE_LITE)
|
|
|
|
.globl mol_trampoline
|
|
.set mol_trampoline, i0x2f00
|
|
|
|
. = 0x3000
|
|
|
|
AltiVecUnavailable:
|
|
EXCEPTION_PROLOG
|
|
#ifdef CONFIG_ALTIVEC
|
|
bne load_up_altivec /* if from user, just load it up */
|
|
#endif /* CONFIG_ALTIVEC */
|
|
addi r3,r1,STACK_FRAME_OVERHEAD
|
|
EXC_XFER_EE_LITE(0xf20, altivec_unavailable_exception)
|
|
|
|
PerformanceMonitor:
|
|
EXCEPTION_PROLOG
|
|
addi r3,r1,STACK_FRAME_OVERHEAD
|
|
EXC_XFER_STD(0xf00, performance_monitor_exception)
|
|
|
|
#ifdef CONFIG_ALTIVEC
|
|
/* Note that the AltiVec support is closely modeled after the FP
|
|
* support. Changes to one are likely to be applicable to the
|
|
* other! */
|
|
load_up_altivec:
|
|
/*
|
|
* Disable AltiVec for the task which had AltiVec previously,
|
|
* and save its AltiVec registers in its thread_struct.
|
|
* Enables AltiVec for use in the kernel on return.
|
|
* On SMP we know the AltiVec units are free, since we give it up every
|
|
* switch. -- Kumar
|
|
*/
|
|
mfmsr r5
|
|
oris r5,r5,MSR_VEC@h
|
|
MTMSRD(r5) /* enable use of AltiVec now */
|
|
isync
|
|
/*
|
|
* For SMP, we don't do lazy AltiVec switching because it just gets too
|
|
* horrendously complex, especially when a task switches from one CPU
|
|
* to another. Instead we call giveup_altivec in switch_to.
|
|
*/
|
|
#ifndef CONFIG_SMP
|
|
tophys(r6,0)
|
|
addis r3,r6,last_task_used_altivec@ha
|
|
lwz r4,last_task_used_altivec@l(r3)
|
|
cmpwi 0,r4,0
|
|
beq 1f
|
|
add r4,r4,r6
|
|
addi r4,r4,THREAD /* want THREAD of last_task_used_altivec */
|
|
SAVE_32VRS(0,r10,r4)
|
|
mfvscr vr0
|
|
li r10,THREAD_VSCR
|
|
stvx vr0,r10,r4
|
|
lwz r5,PT_REGS(r4)
|
|
add r5,r5,r6
|
|
lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5)
|
|
lis r10,MSR_VEC@h
|
|
andc r4,r4,r10 /* disable altivec for previous task */
|
|
stw r4,_MSR-STACK_FRAME_OVERHEAD(r5)
|
|
1:
|
|
#endif /* CONFIG_SMP */
|
|
/* enable use of AltiVec after return */
|
|
oris r9,r9,MSR_VEC@h
|
|
mfspr r5,SPRN_SPRG3 /* current task's THREAD (phys) */
|
|
li r4,1
|
|
li r10,THREAD_VSCR
|
|
stw r4,THREAD_USED_VR(r5)
|
|
lvx vr0,r10,r5
|
|
mtvscr vr0
|
|
REST_32VRS(0,r10,r5)
|
|
#ifndef CONFIG_SMP
|
|
subi r4,r5,THREAD
|
|
sub r4,r4,r6
|
|
stw r4,last_task_used_altivec@l(r3)
|
|
#endif /* CONFIG_SMP */
|
|
/* restore registers and return */
|
|
/* we haven't used ctr or xer or lr */
|
|
b fast_exception_return
|
|
|
|
/*
|
|
* giveup_altivec(tsk)
|
|
* Disable AltiVec for the task given as the argument,
|
|
* and save the AltiVec registers in its thread_struct.
|
|
* Enables AltiVec for use in the kernel on return.
|
|
*/
|
|
|
|
.globl giveup_altivec
|
|
giveup_altivec:
|
|
mfmsr r5
|
|
oris r5,r5,MSR_VEC@h
|
|
SYNC
|
|
MTMSRD(r5) /* enable use of AltiVec now */
|
|
isync
|
|
cmpwi 0,r3,0
|
|
beqlr- /* if no previous owner, done */
|
|
addi r3,r3,THREAD /* want THREAD of task */
|
|
lwz r5,PT_REGS(r3)
|
|
cmpwi 0,r5,0
|
|
SAVE_32VRS(0, r4, r3)
|
|
mfvscr vr0
|
|
li r4,THREAD_VSCR
|
|
stvx vr0,r4,r3
|
|
beq 1f
|
|
lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5)
|
|
lis r3,MSR_VEC@h
|
|
andc r4,r4,r3 /* disable AltiVec for previous task */
|
|
stw r4,_MSR-STACK_FRAME_OVERHEAD(r5)
|
|
1:
|
|
#ifndef CONFIG_SMP
|
|
li r5,0
|
|
lis r4,last_task_used_altivec@ha
|
|
stw r5,last_task_used_altivec@l(r4)
|
|
#endif /* CONFIG_SMP */
|
|
blr
|
|
#endif /* CONFIG_ALTIVEC */
|
|
|
|
/*
|
|
* This code is jumped to from the startup code to copy
|
|
* the kernel image to physical address PHYSICAL_START.
|
|
*/
|
|
relocate_kernel:
|
|
addis r9,r26,klimit@ha /* fetch klimit */
|
|
lwz r25,klimit@l(r9)
|
|
addis r25,r25,-KERNELBASE@h
|
|
lis r3,PHYSICAL_START@h /* Destination base address */
|
|
li r6,0 /* Destination offset */
|
|
li r5,0x4000 /* # bytes of memory to copy */
|
|
bl copy_and_flush /* copy the first 0x4000 bytes */
|
|
addi r0,r3,4f@l /* jump to the address of 4f */
|
|
mtctr r0 /* in copy and do the rest. */
|
|
bctr /* jump to the copy */
|
|
4: mr r5,r25
|
|
bl copy_and_flush /* copy the rest */
|
|
b turn_on_mmu
|
|
|
|
/*
|
|
* Copy routine used to copy the kernel to start at physical address 0
|
|
* and flush and invalidate the caches as needed.
|
|
* r3 = dest addr, r4 = source addr, r5 = copy limit, r6 = start offset
|
|
* on exit, r3, r4, r5 are unchanged, r6 is updated to be >= r5.
|
|
*/
|
|
_ENTRY(copy_and_flush)
|
|
addi r5,r5,-4
|
|
addi r6,r6,-4
|
|
4: li r0,L1_CACHE_BYTES/4
|
|
mtctr r0
|
|
3: addi r6,r6,4 /* copy a cache line */
|
|
lwzx r0,r6,r4
|
|
stwx r0,r6,r3
|
|
bdnz 3b
|
|
dcbst r6,r3 /* write it to memory */
|
|
sync
|
|
icbi r6,r3 /* flush the icache line */
|
|
cmplw 0,r6,r5
|
|
blt 4b
|
|
sync /* additional sync needed on g4 */
|
|
isync
|
|
addi r5,r5,4
|
|
addi r6,r6,4
|
|
blr
|
|
|
|
#ifdef CONFIG_SMP
|
|
#ifdef CONFIG_GEMINI
|
|
.globl __secondary_start_gemini
|
|
__secondary_start_gemini:
|
|
mfspr r4,SPRN_HID0
|
|
ori r4,r4,HID0_ICFI
|
|
li r3,0
|
|
ori r3,r3,HID0_ICE
|
|
andc r4,r4,r3
|
|
mtspr SPRN_HID0,r4
|
|
sync
|
|
b __secondary_start
|
|
#endif /* CONFIG_GEMINI */
|
|
|
|
.globl __secondary_start_mpc86xx
|
|
__secondary_start_mpc86xx:
|
|
mfspr r3, SPRN_PIR
|
|
stw r3, __secondary_hold_acknowledge@l(0)
|
|
mr r24, r3 /* cpu # */
|
|
b __secondary_start
|
|
|
|
.globl __secondary_start_pmac_0
|
|
__secondary_start_pmac_0:
|
|
/* NB the entries for cpus 0, 1, 2 must each occupy 8 bytes. */
|
|
li r24,0
|
|
b 1f
|
|
li r24,1
|
|
b 1f
|
|
li r24,2
|
|
b 1f
|
|
li r24,3
|
|
1:
|
|
/* on powersurge, we come in here with IR=0 and DR=1, and DBAT 0
|
|
set to map the 0xf0000000 - 0xffffffff region */
|
|
mfmsr r0
|
|
rlwinm r0,r0,0,28,26 /* clear DR (0x10) */
|
|
SYNC
|
|
mtmsr r0
|
|
isync
|
|
|
|
.globl __secondary_start
|
|
__secondary_start:
|
|
/* Copy some CPU settings from CPU 0 */
|
|
bl __restore_cpu_setup
|
|
|
|
lis r3,-KERNELBASE@h
|
|
mr r4,r24
|
|
bl call_setup_cpu /* Call setup_cpu for this CPU */
|
|
#ifdef CONFIG_6xx
|
|
lis r3,-KERNELBASE@h
|
|
bl init_idle_6xx
|
|
#endif /* CONFIG_6xx */
|
|
|
|
/* get current_thread_info and current */
|
|
lis r1,secondary_ti@ha
|
|
tophys(r1,r1)
|
|
lwz r1,secondary_ti@l(r1)
|
|
tophys(r2,r1)
|
|
lwz r2,TI_TASK(r2)
|
|
|
|
/* stack */
|
|
addi r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
|
|
li r0,0
|
|
tophys(r3,r1)
|
|
stw r0,0(r3)
|
|
|
|
/* load up the MMU */
|
|
bl load_up_mmu
|
|
|
|
/* ptr to phys current thread */
|
|
tophys(r4,r2)
|
|
addi r4,r4,THREAD /* phys address of our thread_struct */
|
|
CLR_TOP32(r4)
|
|
mtspr SPRN_SPRG3,r4
|
|
li r3,0
|
|
mtspr SPRN_SPRG2,r3 /* 0 => not in RTAS */
|
|
|
|
/* enable MMU and jump to start_secondary */
|
|
li r4,MSR_KERNEL
|
|
FIX_SRR1(r4,r5)
|
|
lis r3,start_secondary@h
|
|
ori r3,r3,start_secondary@l
|
|
mtspr SPRN_SRR0,r3
|
|
mtspr SPRN_SRR1,r4
|
|
SYNC
|
|
RFI
|
|
#endif /* CONFIG_SMP */
|
|
|
|
/*
|
|
* Those generic dummy functions are kept for CPUs not
|
|
* included in CONFIG_6xx
|
|
*/
|
|
#if !defined(CONFIG_6xx)
|
|
_ENTRY(__save_cpu_setup)
|
|
blr
|
|
_ENTRY(__restore_cpu_setup)
|
|
blr
|
|
#endif /* !defined(CONFIG_6xx) */
|
|
|
|
|
|
/*
|
|
* Load stuff into the MMU. Intended to be called with
|
|
* IR=0 and DR=0.
|
|
*/
|
|
load_up_mmu:
|
|
sync /* Force all PTE updates to finish */
|
|
isync
|
|
tlbia /* Clear all TLB entries */
|
|
sync /* wait for tlbia/tlbie to finish */
|
|
TLBSYNC /* ... on all CPUs */
|
|
/* Load the SDR1 register (hash table base & size) */
|
|
lis r6,_SDR1@ha
|
|
tophys(r6,r6)
|
|
lwz r6,_SDR1@l(r6)
|
|
mtspr SPRN_SDR1,r6
|
|
li r0,16 /* load up segment register values */
|
|
mtctr r0 /* for context 0 */
|
|
lis r3,0x2000 /* Ku = 1, VSID = 0 */
|
|
li r4,0
|
|
3: mtsrin r3,r4
|
|
addi r3,r3,0x111 /* increment VSID */
|
|
addis r4,r4,0x1000 /* address of next segment */
|
|
bdnz 3b
|
|
|
|
/* Load the BAT registers with the values set up by MMU_init.
|
|
MMU_init takes care of whether we're on a 601 or not. */
|
|
mfpvr r3
|
|
srwi r3,r3,16
|
|
cmpwi r3,1
|
|
lis r3,BATS@ha
|
|
addi r3,r3,BATS@l
|
|
tophys(r3,r3)
|
|
LOAD_BAT(0,r3,r4,r5)
|
|
LOAD_BAT(1,r3,r4,r5)
|
|
LOAD_BAT(2,r3,r4,r5)
|
|
LOAD_BAT(3,r3,r4,r5)
|
|
BEGIN_MMU_FTR_SECTION
|
|
LOAD_BAT(4,r3,r4,r5)
|
|
LOAD_BAT(5,r3,r4,r5)
|
|
LOAD_BAT(6,r3,r4,r5)
|
|
LOAD_BAT(7,r3,r4,r5)
|
|
END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
|
|
blr
|
|
|
|
/*
|
|
* This is where the main kernel code starts.
|
|
*/
|
|
start_here:
|
|
/* ptr to current */
|
|
lis r2,init_task@h
|
|
ori r2,r2,init_task@l
|
|
/* Set up for using our exception vectors */
|
|
/* ptr to phys current thread */
|
|
tophys(r4,r2)
|
|
addi r4,r4,THREAD /* init task's THREAD */
|
|
CLR_TOP32(r4)
|
|
mtspr SPRN_SPRG3,r4
|
|
li r3,0
|
|
mtspr SPRN_SPRG2,r3 /* 0 => not in RTAS */
|
|
|
|
/* stack */
|
|
lis r1,init_thread_union@ha
|
|
addi r1,r1,init_thread_union@l
|
|
li r0,0
|
|
stwu r0,THREAD_SIZE-STACK_FRAME_OVERHEAD(r1)
|
|
/*
|
|
* Do early platform-specific initialization,
|
|
* and set up the MMU.
|
|
*/
|
|
mr r3,r31
|
|
mr r4,r30
|
|
bl machine_init
|
|
bl __save_cpu_setup
|
|
bl MMU_init
|
|
|
|
/*
|
|
* Go back to running unmapped so we can load up new values
|
|
* for SDR1 (hash table pointer) and the segment registers
|
|
* and change to using our exception vectors.
|
|
*/
|
|
lis r4,2f@h
|
|
ori r4,r4,2f@l
|
|
tophys(r4,r4)
|
|
li r3,MSR_KERNEL & ~(MSR_IR|MSR_DR)
|
|
FIX_SRR1(r3,r5)
|
|
mtspr SPRN_SRR0,r4
|
|
mtspr SPRN_SRR1,r3
|
|
SYNC
|
|
RFI
|
|
/* Load up the kernel context */
|
|
2: bl load_up_mmu
|
|
|
|
#ifdef CONFIG_BDI_SWITCH
|
|
/* Add helper information for the Abatron bdiGDB debugger.
|
|
* We do this here because we know the mmu is disabled, and
|
|
* will be enabled for real in just a few instructions.
|
|
*/
|
|
lis r5, abatron_pteptrs@h
|
|
ori r5, r5, abatron_pteptrs@l
|
|
stw r5, 0xf0(r0) /* This much match your Abatron config */
|
|
lis r6, swapper_pg_dir@h
|
|
ori r6, r6, swapper_pg_dir@l
|
|
tophys(r5, r5)
|
|
stw r6, 0(r5)
|
|
#endif /* CONFIG_BDI_SWITCH */
|
|
|
|
/* Now turn on the MMU for real! */
|
|
li r4,MSR_KERNEL
|
|
FIX_SRR1(r4,r5)
|
|
lis r3,start_kernel@h
|
|
ori r3,r3,start_kernel@l
|
|
mtspr SPRN_SRR0,r3
|
|
mtspr SPRN_SRR1,r4
|
|
SYNC
|
|
RFI
|
|
|
|
/*
|
|
* void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next);
|
|
*
|
|
* Set up the segment registers for a new context.
|
|
*/
|
|
_ENTRY(switch_mmu_context)
|
|
lwz r3,MMCONTEXTID(r4)
|
|
cmpwi cr0,r3,0
|
|
blt- 4f
|
|
mulli r3,r3,897 /* multiply context by skew factor */
|
|
rlwinm r3,r3,4,8,27 /* VSID = (context & 0xfffff) << 4 */
|
|
addis r3,r3,0x6000 /* Set Ks, Ku bits */
|
|
li r0,NUM_USER_SEGMENTS
|
|
mtctr r0
|
|
|
|
#ifdef CONFIG_BDI_SWITCH
|
|
/* Context switch the PTE pointer for the Abatron BDI2000.
|
|
* The PGDIR is passed as second argument.
|
|
*/
|
|
lwz r4,MM_PGD(r4)
|
|
lis r5, KERNELBASE@h
|
|
lwz r5, 0xf0(r5)
|
|
stw r4, 0x4(r5)
|
|
#endif
|
|
li r4,0
|
|
isync
|
|
3:
|
|
mtsrin r3,r4
|
|
addi r3,r3,0x111 /* next VSID */
|
|
rlwinm r3,r3,0,8,3 /* clear out any overflow from VSID field */
|
|
addis r4,r4,0x1000 /* address of next segment */
|
|
bdnz 3b
|
|
sync
|
|
isync
|
|
blr
|
|
4: trap
|
|
EMIT_BUG_ENTRY 4b,__FILE__,__LINE__,0
|
|
blr
|
|
|
|
/*
|
|
* An undocumented "feature" of 604e requires that the v bit
|
|
* be cleared before changing BAT values.
|
|
*
|
|
* Also, newer IBM firmware does not clear bat3 and 4 so
|
|
* this makes sure it's done.
|
|
* -- Cort
|
|
*/
|
|
clear_bats:
|
|
li r10,0
|
|
mfspr r9,SPRN_PVR
|
|
rlwinm r9,r9,16,16,31 /* r9 = 1 for 601, 4 for 604 */
|
|
cmpwi r9, 1
|
|
beq 1f
|
|
|
|
mtspr SPRN_DBAT0U,r10
|
|
mtspr SPRN_DBAT0L,r10
|
|
mtspr SPRN_DBAT1U,r10
|
|
mtspr SPRN_DBAT1L,r10
|
|
mtspr SPRN_DBAT2U,r10
|
|
mtspr SPRN_DBAT2L,r10
|
|
mtspr SPRN_DBAT3U,r10
|
|
mtspr SPRN_DBAT3L,r10
|
|
1:
|
|
mtspr SPRN_IBAT0U,r10
|
|
mtspr SPRN_IBAT0L,r10
|
|
mtspr SPRN_IBAT1U,r10
|
|
mtspr SPRN_IBAT1L,r10
|
|
mtspr SPRN_IBAT2U,r10
|
|
mtspr SPRN_IBAT2L,r10
|
|
mtspr SPRN_IBAT3U,r10
|
|
mtspr SPRN_IBAT3L,r10
|
|
BEGIN_MMU_FTR_SECTION
|
|
/* Here's a tweak: at this point, CPU setup have
|
|
* not been called yet, so HIGH_BAT_EN may not be
|
|
* set in HID0 for the 745x processors. However, it
|
|
* seems that doesn't affect our ability to actually
|
|
* write to these SPRs.
|
|
*/
|
|
mtspr SPRN_DBAT4U,r10
|
|
mtspr SPRN_DBAT4L,r10
|
|
mtspr SPRN_DBAT5U,r10
|
|
mtspr SPRN_DBAT5L,r10
|
|
mtspr SPRN_DBAT6U,r10
|
|
mtspr SPRN_DBAT6L,r10
|
|
mtspr SPRN_DBAT7U,r10
|
|
mtspr SPRN_DBAT7L,r10
|
|
mtspr SPRN_IBAT4U,r10
|
|
mtspr SPRN_IBAT4L,r10
|
|
mtspr SPRN_IBAT5U,r10
|
|
mtspr SPRN_IBAT5L,r10
|
|
mtspr SPRN_IBAT6U,r10
|
|
mtspr SPRN_IBAT6L,r10
|
|
mtspr SPRN_IBAT7U,r10
|
|
mtspr SPRN_IBAT7L,r10
|
|
END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
|
|
blr
|
|
|
|
flush_tlbs:
|
|
lis r10, 0x40
|
|
1: addic. r10, r10, -0x1000
|
|
tlbie r10
|
|
bgt 1b
|
|
sync
|
|
blr
|
|
|
|
mmu_off:
|
|
addi r4, r3, __after_mmu_off - _start
|
|
mfmsr r3
|
|
andi. r0,r3,MSR_DR|MSR_IR /* MMU enabled? */
|
|
beqlr
|
|
andc r3,r3,r0
|
|
mtspr SPRN_SRR0,r4
|
|
mtspr SPRN_SRR1,r3
|
|
sync
|
|
RFI
|
|
|
|
/*
|
|
* Use the first pair of BAT registers to map the 1st 16MB
|
|
* of RAM to PAGE_OFFSET. From this point on we can't safely
|
|
* call OF any more.
|
|
*/
|
|
initial_bats:
|
|
lis r11,PAGE_OFFSET@h
|
|
mfspr r9,SPRN_PVR
|
|
rlwinm r9,r9,16,16,31 /* r9 = 1 for 601, 4 for 604 */
|
|
cmpwi 0,r9,1
|
|
bne 4f
|
|
ori r11,r11,4 /* set up BAT registers for 601 */
|
|
li r8,0x7f /* valid, block length = 8MB */
|
|
oris r9,r11,0x800000@h /* set up BAT reg for 2nd 8M */
|
|
oris r10,r8,0x800000@h /* set up BAT reg for 2nd 8M */
|
|
mtspr SPRN_IBAT0U,r11 /* N.B. 601 has valid bit in */
|
|
mtspr SPRN_IBAT0L,r8 /* lower BAT register */
|
|
mtspr SPRN_IBAT1U,r9
|
|
mtspr SPRN_IBAT1L,r10
|
|
isync
|
|
blr
|
|
|
|
4: tophys(r8,r11)
|
|
#ifdef CONFIG_SMP
|
|
ori r8,r8,0x12 /* R/W access, M=1 */
|
|
#else
|
|
ori r8,r8,2 /* R/W access */
|
|
#endif /* CONFIG_SMP */
|
|
ori r11,r11,BL_256M<<2|0x2 /* set up BAT registers for 604 */
|
|
|
|
mtspr SPRN_DBAT0L,r8 /* N.B. 6xx (not 601) have valid */
|
|
mtspr SPRN_DBAT0U,r11 /* bit in upper BAT register */
|
|
mtspr SPRN_IBAT0L,r8
|
|
mtspr SPRN_IBAT0U,r11
|
|
isync
|
|
blr
|
|
|
|
|
|
#ifdef CONFIG_BOOTX_TEXT
|
|
setup_disp_bat:
|
|
/*
|
|
* setup the display bat prepared for us in prom.c
|
|
*/
|
|
mflr r8
|
|
bl reloc_offset
|
|
mtlr r8
|
|
addis r8,r3,disp_BAT@ha
|
|
addi r8,r8,disp_BAT@l
|
|
cmpwi cr0,r8,0
|
|
beqlr
|
|
lwz r11,0(r8)
|
|
lwz r8,4(r8)
|
|
mfspr r9,SPRN_PVR
|
|
rlwinm r9,r9,16,16,31 /* r9 = 1 for 601, 4 for 604 */
|
|
cmpwi 0,r9,1
|
|
beq 1f
|
|
mtspr SPRN_DBAT3L,r8
|
|
mtspr SPRN_DBAT3U,r11
|
|
blr
|
|
1: mtspr SPRN_IBAT3L,r8
|
|
mtspr SPRN_IBAT3U,r11
|
|
blr
|
|
#endif /* CONFIG_BOOTX_TEXT */
|
|
|
|
#ifdef CONFIG_PPC_EARLY_DEBUG_CPM
|
|
setup_cpm_bat:
|
|
lis r8, 0xf000
|
|
ori r8, r8, 0x002a
|
|
mtspr SPRN_DBAT1L, r8
|
|
|
|
lis r11, 0xf000
|
|
ori r11, r11, (BL_1M << 2) | 2
|
|
mtspr SPRN_DBAT1U, r11
|
|
|
|
blr
|
|
#endif
|
|
|
|
#ifdef CONFIG_8260
|
|
/* Jump into the system reset for the rom.
|
|
* We first disable the MMU, and then jump to the ROM reset address.
|
|
*
|
|
* r3 is the board info structure, r4 is the location for starting.
|
|
* I use this for building a small kernel that can load other kernels,
|
|
* rather than trying to write or rely on a rom monitor that can tftp load.
|
|
*/
|
|
.globl m8260_gorom
|
|
m8260_gorom:
|
|
mfmsr r0
|
|
rlwinm r0,r0,0,17,15 /* clear MSR_EE in r0 */
|
|
sync
|
|
mtmsr r0
|
|
sync
|
|
mfspr r11, SPRN_HID0
|
|
lis r10, 0
|
|
ori r10,r10,HID0_ICE|HID0_DCE
|
|
andc r11, r11, r10
|
|
mtspr SPRN_HID0, r11
|
|
isync
|
|
li r5, MSR_ME|MSR_RI
|
|
lis r6,2f@h
|
|
addis r6,r6,-KERNELBASE@h
|
|
ori r6,r6,2f@l
|
|
mtspr SPRN_SRR0,r6
|
|
mtspr SPRN_SRR1,r5
|
|
isync
|
|
sync
|
|
rfi
|
|
2:
|
|
mtlr r4
|
|
blr
|
|
#endif
|
|
|
|
|
|
/*
|
|
* We put a few things here that have to be page-aligned.
|
|
* This stuff goes at the beginning of the data segment,
|
|
* which is page-aligned.
|
|
*/
|
|
.data
|
|
.globl sdata
|
|
sdata:
|
|
.globl empty_zero_page
|
|
empty_zero_page:
|
|
.space 4096
|
|
|
|
.globl swapper_pg_dir
|
|
swapper_pg_dir:
|
|
.space PGD_TABLE_SIZE
|
|
|
|
.globl intercept_table
|
|
intercept_table:
|
|
.long 0, 0, i0x200, i0x300, i0x400, 0, i0x600, i0x700
|
|
.long i0x800, 0, 0, 0, 0, i0xd00, 0, 0
|
|
.long 0, 0, 0, i0x1300, 0, 0, 0, 0
|
|
.long 0, 0, 0, 0, 0, 0, 0, 0
|
|
.long 0, 0, 0, 0, 0, 0, 0, 0
|
|
.long 0, 0, 0, 0, 0, 0, 0, 0
|
|
|
|
/* Room for two PTE pointers, usually the kernel and current user pointers
|
|
* to their respective root page table.
|
|
*/
|
|
abatron_pteptrs:
|
|
.space 8
|