Rename locore.S to locore-v4.S and add a new locore-v6.S for starting up

armv6/7 systems.  We need to use some new armv6/7 features at startup
and splitting the implemenations to separate files will be more maintainable
than adding even more #ifdef sections to locore.S.

Because of the standardized interfaces to cache and MMU operations in armv7,
we can tolerate the kernel being entered with caches enabled.  This allows
running u-boot and loader(8) with caches enabled, and the performance
improvement can be dramatic (boot times can be cut from over a minute
to under 30 seconds).  The new implementation also has more robust cache
and mmu sequences for launching AP cores, and it paves the way for
upcoming changes to the pmap code which will use the TEX remap feature.

Changes in mp_machdep.c work with the new behavior in locore-v6 mp_entry,
and also reuse the original boot-time page tables to get transitioned
from physical to virtual addressing before installing the normal tables.

Submitted by Svatopluk Kraus and Michal Meloun with some changes by me.
This commit is contained in:
Ian Lepore 2014-12-30 03:17:53 +00:00
parent 10fe3ac09b
commit dc15bc80b7
3 changed files with 538 additions and 27 deletions

537
sys/arm/arm/locore-v6.S Normal file
View File

@ -0,0 +1,537 @@
/*-
* Copyright 2004-2014 Olivier Houchard <cognet@FreeBSD.org>
* Copyright 2012-2014 Ian Lepore <ian@FreeBSD.org>
* Copyright 2013-2014 Andrew Turner <andrew@FreeBSD.org>
* Copyright 2014 Svatopluk Kraus <onwahe@gmail.com>
* Copyright 2014 Michal Meloun <meloun@miracle.cz>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "assym.s"
#include <sys/syscall.h>
#include <machine/asm.h>
#include <machine/asmacros.h>
#include <machine/armreg.h>
#include <machine/sysreg.h>
#include <machine/cpuconf.h>
#include <machine/pte.h>
__FBSDID("$FreeBSD$");
#ifndef ARM_NEW_PMAP
#define PTE1_OFFSET L1_S_OFFSET
#define PTE1_SHIFT L1_S_SHIFT
#define PTE1_SIZE L1_S_SIZE
#endif
/* A small statically-allocated stack used only during initarm() and AP startup. */
#define INIT_ARM_STACK_SIZE 2048
.text
.align 0
/*
* On entry for FreeBSD boot ABI:
* r0 - metadata pointer or 0 (boothowto on AT91's boot2)
* r1 - if (r0 == 0) then metadata pointer
* On entry for Linux boot ABI:
* r0 - 0
* r1 - machine type (passed as arg2 to initarm)
* r2 - Pointer to a tagged list or dtb image (phys addr) (passed as arg1 initarm)
*
* For both types of boot we gather up the args, put them in a struct arm_boot_params
* structure and pass that to initarm.
*/
.globl btext
btext:
ASENTRY_NP(_start)
STOP_UNWINDING /* Can't unwind into the bootloader! */
/* Make sure interrupts are disabled. */
cpsid ifa
mov r8, r0 /* 0 or boot mode from boot2 */
mov r9, r1 /* Save Machine type */
mov r10, r2 /* Save meta data */
mov r11, r3 /* Future expansion */
/*
* Check whether data cache is enabled. If it is, then we know
* current tags are valid (not power-on garbage values) and there
* might be dirty lines that need cleaning. Disable cache to prevent
* new lines being allocated, then call wbinv_poc_all to clean it.
*/
mrc CP15_SCTLR(r7)
tst r7, #CPU_CONTROL_DC_ENABLE
beq 1f
bic r7, #CPU_CONTROL_DC_ENABLE
mcr CP15_SCTLR(r7)
ISB
bl dcache_wbinv_poc_all
/*
* Now there are no dirty lines, but there may still be lines marked
* valid. Disable all caches and the MMU, and invalidate everything
* before setting up new page tables and re-enabling the mmu.
*/
1:
bic r7, #CPU_CONTROL_MMU_ENABLE
bic r7, #CPU_CONTROL_IC_ENABLE
bic r7, #CPU_CONTROL_UNAL_ENABLE
bic r7, #CPU_CONTROL_BPRD_ENABLE
bic r7, #CPU_CONTROL_SW_ENABLE
orr r7, #CPU_CONTROL_AFLT_ENABLE
orr r7, #CPU_CONTROL_VECRELOC
mcr CP15_SCTLR(r7)
ISB
bl dcache_inv_poc_all
mcr CP15_ICIALLU
ISB
/*
* Build page table from scratch.
*/
/* Calculate the physical address of the startup pagetable. */
adr r0, Lpagetable
bl translate_va_to_pa
/*
* Map PA == VA
*/
/* Find the start kernels load address */
adr r5, _start
ldr r2, =(PTE1_OFFSET)
bic r5, r2
mov r1, r5
mov r2, r5
/* Map 64MiB, preserved over calls to build_pagetables */
mov r3, #64
bl build_pagetables
/* Create the kernel map to jump to */
mov r1, r5
ldr r2, =(KERNVIRTADDR)
bl build_pagetables
#if defined(SOCDEV_PA) && defined(SOCDEV_VA)
/* Create the custom map used for early_printf(). */
ldr r1, =SOCDEV_PA
ldr r2, =SOCDEV_VA
bl build_pagetables
#endif
bl init_mmu
/* Switch to virtual addresses. */
ldr pc, =1f
1:
/* Setup stack, clear BSS */
ldr r1, =.Lstart
ldmia r1, {r1, r2, sp} /* Set initial stack and */
add sp, sp, #INIT_ARM_STACK_SIZE
sub r2, r2, r1 /* get zero init data */
mov r3, #0
2:
str r3, [r1], #0x0004 /* get zero init data */
subs r2, r2, #4
bgt 2b
mov r1, #28 /* loader info size is 28 bytes also second arg */
subs sp, sp, r1 /* allocate arm_boot_params struct on stack */
mov r0, sp /* loader info pointer is first arg */
bic sp, sp, #7 /* align stack to 8 bytes */
str r1, [r0] /* Store length of loader info */
str r8, [r0, #4] /* Store r0 from boot loader */
str r9, [r0, #8] /* Store r1 from boot loader */
str r10, [r0, #12] /* store r2 from boot loader */
str r11, [r0, #16] /* store r3 from boot loader */
str r5, [r0, #20] /* store the physical address */
adr r4, Lpagetable /* load the pagetable address */
ldr r5, [r4, #4]
str r5, [r0, #24] /* store the pagetable address */
mov fp, #0 /* trace back starts here */
bl _C_LABEL(initarm) /* Off we go */
/* init arm will return the new stack pointer. */
mov sp, r0
bl _C_LABEL(mi_startup) /* call mi_startup()! */
ldr r0, =.Lmainreturned
b _C_LABEL(panic)
/* NOTREACHED */
END(_start)
#define VA_TO_PA_POINTER(name, table) \
name: ;\
.word . ;\
.word table
/*
* Returns the physical address of a magic va to pa pointer.
* r0 - The pagetable data pointer. This must be built using the
* VA_TO_PA_POINTER macro.
* e.g.
* VA_TO_PA_POINTER(Lpagetable, pagetable)
* ...
* adr r0, Lpagetable
* bl translate_va_to_pa
* r0 will now contain the physical address of pagetable
* r1, r2 - Trashed
*/
translate_va_to_pa:
ldr r1, [r0]
sub r2, r1, r0
/* At this point: r2 = VA - PA */
/*
* Find the physical address of the table. After these two
* instructions:
* r1 = va(pagetable)
*
* r0 = va(pagetable) - (VA - PA)
* = va(pagetable) - VA + PA
* = pa(pagetable)
*/
ldr r1, [r0, #4]
sub r0, r1, r2
mov pc, lr
/*
* Init MMU
* r0 - The table base address
*/
ASENTRY_NP(init_mmu)
/* Setup TLB and MMU registers */
mcr CP15_TTBR0(r0) /* Set TTB */
mov r0, #0
mcr CP15_CONTEXTIDR(r0) /* Set ASID to 0 */
/* Set the Domain Access register */
mov r0, #((DOMAIN_CLIENT << (PMAP_DOMAIN_KERNEL*2)) | DOMAIN_CLIENT)
mcr CP15_DACR(r0)
#ifdef ARM_NEW_PMAP
/*
* Set TEX remap registers
* - All is set to uncacheable memory
*/
ldr r0, =0xAAAAA
mrc CP15_PRRR(r0)
mov r0, #0
mcr CP15_NMRR(r0)
#endif
mcr CP15_TLBIALL /* Flush TLB */
DSB
ISB
/* Enable MMU */
mrc CP15_SCTLR(r0)
orr r0, r0, #CPU_CONTROL_MMU_ENABLE
orr r0, r0, #CPU_CONTROL_V6_EXTPAGE
#ifdef ARM_NEW_PMAP
orr r0, r0, #CPU_CONTROL_TR_ENABLE
#endif
orr r0, r0, #CPU_CONTROL_AF_ENABLE
mcr CP15_SCTLR(r0)
DSB
ISB
mcr CP15_TLBIALL /* Flush TLB */
mcr CP15_BPIALL /* Flush Branch predictor */
ISB
mov pc, lr
END(init_mmu)
/*
* Init SMP coherent mode, enable caching and switch to final MMU table.
* Called with disabled caches
* r0 - The table base address
* r1 - clear bits for aux register
* r2 - set bits for aux register
*/
ASENTRY_NP(reinit_mmu)
push {r4-r11, lr}
mov r4, r0
mov r5, r1
mov r6, r2
/* !! Be very paranoid here !! */
/* !! We cannot write single bit here !! */
#if 0 /* XXX writeback shouldn't be necessary */
/* Write back and invalidate all integrated caches */
bl dcache_wbinv_poc_all
#else
bl dcache_inv_pou_all
#endif
mcr CP15_ICIALLU
ISB
/* Set auxiliary register */
mrc CP15_ACTLR(r7)
bic r8, r7, r5 /* Mask bits */
eor r8, r8, r6 /* Set bits */
teq r7, r8
mcrne CP15_ACTLR(r8)
ISB
/* Enable caches. */
mrc CP15_SCTLR(r7)
orr r7, #CPU_CONTROL_DC_ENABLE
orr r7, #CPU_CONTROL_IC_ENABLE
orr r7, #CPU_CONTROL_BPRD_ENABLE
mcr CP15_SCTLR(r7)
DSB
mcr CP15_TTBR0(r4) /* Set new TTB */
DSB
ISB
/* Flush all TLBs */
mcr CP15_TLBIALL
DSB
ISB
#if 0 /* XXX writeback shouldn't be necessary */
/* Write back and invalidate all integrated caches */
bl dcache_wbinv_poc_all
#else
bl dcache_inv_pou_all
#endif
mcr CP15_ICIALLU
ISB
pop {r4-r11, pc}
END(reinit_mmu)
/*
* Builds the page table
* r0 - The table base address
* r1 - The physical address (trashed)
* r2 - The virtual address (trashed)
* r3 - The number of 1MiB sections
* r4 - Trashed
*
* Addresses must be 1MiB aligned
*/
ASENTRY_NP(build_pagetables)
/* Set the required page attributed */
#if defined(ARM_NEW_PMAP)
ldr r4, =PTE1_V|PTE1_A|PTE1_AP_KRW|TEX1_CLASS_0
#elif defined(SMP)
ldr r4, =(L1_TYPE_S|L1_S_C|L1_S_AP(AP_KRW)|L1_SHARED)
#else
ldr r4, =(L1_TYPE_S|L1_S_C|L1_S_AP(AP_KRW))
#endif
orr r1, r4
/* Move the virtual address to the correct bit location */
lsr r2, #(PTE1_SHIFT - 2)
mov r4, r3
1:
str r1, [r0, r2]
add r2, r2, #4
add r1, r1, #(PTE1_SIZE)
adds r4, r4, #-1
bhi 1b
mov pc, lr
VA_TO_PA_POINTER(Lpagetable, boot_pt1)
.Lstart:
.word _edata
.word _ebss
.word svcstk
.Lmainreturned:
.asciz "main() returned"
.align 0
.bss
svcstk:
.space INIT_ARM_STACK_SIZE * MAXCPU
/*
* Memory for the initial pagetable. We are unable to place this in
* the bss as this will be cleared after the table is loaded.
*/
.section ".init_pagetable"
.align 14 /* 16KiB aligned */
.globl boot_pt1
boot_pt1:
.space L1_TABLE_SIZE
.text
.align 0
.Lcpufuncs:
.word _C_LABEL(cpufuncs)
#if defined(SMP)
ASENTRY_NP(mpentry)
/* Make sure interrupts are disabled. */
cpsid ifa
/* Setup core, disable all caches. */
mrc CP15_SCTLR(r0)
bic r0, #CPU_CONTROL_MMU_ENABLE
bic r0, #CPU_CONTROL_DC_ENABLE
bic r0, #CPU_CONTROL_IC_ENABLE
bic r0, #CPU_CONTROL_UNAL_ENABLE
bic r0, #CPU_CONTROL_BPRD_ENABLE
bic r0, #CPU_CONTROL_SW_ENABLE
orr r0, #CPU_CONTROL_AFLT_ENABLE
orr r0, #CPU_CONTROL_VECRELOC
mcr CP15_SCTLR(r0)
ISB
/* Invalidate L1 cache I+D cache */
bl dcache_inv_pou_all
mcr CP15_ICIALLU
ISB
/* Find the delta between VA and PA */
adr r0, Lpagetable
bl translate_va_to_pa
bl init_mmu
adr r1, .Lstart
ldmia r1, {r1, r2, sp} /* Set initial stack and */
mrc p15, 0, r0, c0, c0, 5
and r0, r0, #15
mov r1, #INIT_ARM_STACK_SIZE
mul r2, r1, r0
add sp, sp, r2
str r1, [sp]
/* Switch to virtual addresses. */
ldr pc, =1f
1:
mov fp, #0 /* trace back starts here */
bl _C_LABEL(init_secondary) /* Off we go */
adr r0, .Lmpreturned
b _C_LABEL(panic)
/* NOTREACHED */
.Lmpreturned:
.asciz "init_secondary() returned"
.align 0
END(mpentry)
#endif
ENTRY_NP(cpu_halt)
/* XXX re-implement !!! */
cpsid ifa
bl dcache_wbinv_poc_all
ldr r4, .Lcpu_reset_address
ldr r4, [r4]
teq r4, #0
movne pc, r4
1:
wfi
b 1b
/*
* _cpu_reset_address contains the address to branch to, to complete
* the cpu reset after turning the MMU off
* This variable is provided by the hardware specific code
*/
.Lcpu_reset_address:
.word _C_LABEL(cpu_reset_address)
END(cpu_halt)
/*
* setjump + longjmp
*/
ENTRY(setjmp)
stmia r0, {r4-r14}
mov r0, #0x00000000
RET
END(setjmp)
ENTRY(longjmp)
ldmia r0, {r4-r14}
mov r0, #0x00000001
RET
END(longjmp)
.data
.global _C_LABEL(esym)
_C_LABEL(esym): .word _C_LABEL(end)
ENTRY_NP(abort)
b _C_LABEL(abort)
END(abort)
ENTRY_NP(sigcode)
mov r0, sp
add r0, r0, #SIGF_UC
/*
* Call the sigreturn system call.
*
* We have to load r7 manually rather than using
* "ldr r7, =SYS_sigreturn" to ensure the value of szsigcode is
* correct. Using the alternative places esigcode at the address
* of the data rather than the address one past the data.
*/
ldr r7, [pc, #12] /* Load SYS_sigreturn */
swi SYS_sigreturn
/* Well if that failed we better exit quick ! */
ldr r7, [pc, #8] /* Load SYS_exit */
swi SYS_exit
/* Branch back to retry SYS_sigreturn */
b . - 16
.word SYS_sigreturn
.word SYS_exit
.align 0
.global _C_LABEL(esigcode)
_C_LABEL(esigcode):
.data
.global szsigcode
szsigcode:
.long esigcode-sigcode
END(sigcode)
/* End of locore.S */

View File

@ -62,7 +62,6 @@ __FBSDID("$FreeBSD$");
#include "opt_smp.h"
void *temp_pagetable;
extern struct pcpu __pcpu[];
/* used to hold the AP's until we are ready to release them */
struct mtx ap_boot_mtx;
@ -112,8 +111,6 @@ void
cpu_mp_start(void)
{
int error, i;
vm_offset_t temp_pagetable_va;
vm_paddr_t addr, addr_end;
mtx_init(&ap_boot_mtx, "ap boot", NULL, MTX_SPIN);
@ -121,30 +118,10 @@ cpu_mp_start(void)
for(i = 0; i < (mp_ncpus - 1); i++)
dpcpu[i] = (void *)kmem_malloc(kernel_arena, DPCPU_SIZE,
M_WAITOK | M_ZERO);
temp_pagetable_va = (vm_offset_t)contigmalloc(L1_TABLE_SIZE,
M_TEMP, 0, 0x0, 0xffffffff, L1_TABLE_SIZE, 0);
addr = arm_physmem_kernaddr;
addr_end = (vm_offset_t)&_end - KERNVIRTADDR + arm_physmem_kernaddr;
addr_end &= ~L1_S_OFFSET;
addr_end += L1_S_SIZE;
bzero((void *)temp_pagetable_va, L1_TABLE_SIZE);
for (addr = arm_physmem_kernaddr; addr <= addr_end; addr += L1_S_SIZE) {
((int *)(temp_pagetable_va))[addr >> L1_S_SHIFT] =
L1_TYPE_S|L1_SHARED|L1_S_C|L1_S_B|L1_S_AP(AP_KRW)|L1_S_DOM(PMAP_DOMAIN_KERNEL)|addr;
((int *)(temp_pagetable_va))[(addr -
arm_physmem_kernaddr + KERNVIRTADDR) >> L1_S_SHIFT] =
L1_TYPE_S|L1_SHARED|L1_S_C|L1_S_B|L1_S_AP(AP_KRW)|L1_S_DOM(PMAP_DOMAIN_KERNEL)|addr;
}
#if defined(CPU_MV_PJ4B)
/* Add ARMADAXP registers required for snoop filter initialization */
((int *)(temp_pagetable_va))[MV_BASE >> L1_S_SHIFT] =
L1_TYPE_S|L1_SHARED|L1_S_B|L1_S_AP(AP_KRW)|fdt_immr_pa;
#endif
temp_pagetable = (void*)(vtophys(temp_pagetable_va));
cpu_idcache_wbinv_all();
cpu_l2cache_wbinv_all();
cpu_idcache_wbinv_all();
/* Initialize boot code and start up processors */
platform_mp_start_ap();
@ -157,7 +134,6 @@ cpu_mp_start(void)
for (i = 1; i < mp_ncpus; i++)
CPU_SET(i, &all_cpus);
contigfree((void *)temp_pagetable_va, L1_TABLE_SIZE, M_TEMP);
}
/* Introduce rest of cores to the world */
@ -175,8 +151,6 @@ init_secondary(int cpu)
uint32_t loop_counter;
int start = 0, end = 0;
cpu_idcache_inv_all();
cpu_setup(NULL);
setttb(pmap_pa);
cpu_tlb_flushID();