https://github.com/torvalds/linux
Tip revision: 1def630a6a49dda5bc89dfbd86656293640456f0 authored by Linus Torvalds on 06 June 2006, 00:57:02 UTC
Linux 2.6.17-rc6
Linux 2.6.17-rc6
Tip revision: 1def630
c-sb1.c
/*
* Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
* Copyright (C) 1997, 2001 Ralf Baechle (ralf@gnu.org)
* Copyright (C) 2000, 2001, 2002, 2003 Broadcom Corporation
* Copyright (C) 2004 Maciej W. Rozycki
*
* 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; either version 2
* of the License, or (at your option) any later version.
*
* 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. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <linux/config.h>
#include <linux/init.h>
#include <asm/asm.h>
#include <asm/bootinfo.h>
#include <asm/cacheops.h>
#include <asm/cpu.h>
#include <asm/mipsregs.h>
#include <asm/mmu_context.h>
#include <asm/uaccess.h>
extern void sb1_dma_init(void);
/* These are probed at ld_mmu time */
static unsigned long icache_size;
static unsigned long dcache_size;
static unsigned short icache_line_size;
static unsigned short dcache_line_size;
static unsigned int icache_index_mask;
static unsigned int dcache_index_mask;
static unsigned short icache_assoc;
static unsigned short dcache_assoc;
static unsigned short icache_sets;
static unsigned short dcache_sets;
static unsigned int icache_range_cutoff;
static unsigned int dcache_range_cutoff;
/*
* The dcache is fully coherent to the system, with one
* big caveat: the instruction stream. In other words,
* if we miss in the icache, and have dirty data in the
* L1 dcache, then we'll go out to memory (or the L2) and
* get the not-as-recent data.
*
* So the only time we have to flush the dcache is when
* we're flushing the icache. Since the L2 is fully
* coherent to everything, including I/O, we never have
* to flush it
*/
#define cache_set_op(op, addr) \
__asm__ __volatile__( \
" .set noreorder \n" \
" .set mips64\n\t \n" \
" cache %0, (0<<13)(%1) \n" \
" cache %0, (1<<13)(%1) \n" \
" cache %0, (2<<13)(%1) \n" \
" cache %0, (3<<13)(%1) \n" \
" .set mips0 \n" \
" .set reorder" \
: \
: "i" (op), "r" (addr))
#define sync() \
__asm__ __volatile( \
" .set mips64\n\t \n" \
" sync \n" \
" .set mips0")
#define mispredict() \
__asm__ __volatile__( \
" bnezl $0, 1f \n" /* Force mispredict */ \
"1: \n");
/*
* Writeback and invalidate the entire dcache
*/
static inline void __sb1_writeback_inv_dcache_all(void)
{
unsigned long addr = 0;
while (addr < dcache_line_size * dcache_sets) {
cache_set_op(Index_Writeback_Inv_D, addr);
addr += dcache_line_size;
}
}
/*
* Writeback and invalidate a range of the dcache. The addresses are
* virtual, and since we're using index ops and bit 12 is part of both
* the virtual frame and physical index, we have to clear both sets
* (bit 12 set and cleared).
*/
static inline void __sb1_writeback_inv_dcache_range(unsigned long start,
unsigned long end)
{
unsigned long index;
start &= ~(dcache_line_size - 1);
end = (end + dcache_line_size - 1) & ~(dcache_line_size - 1);
while (start != end) {
index = start & dcache_index_mask;
cache_set_op(Index_Writeback_Inv_D, index);
cache_set_op(Index_Writeback_Inv_D, index ^ (1<<12));
start += dcache_line_size;
}
sync();
}
/*
* Writeback and invalidate a range of the dcache. With physical
* addresseses, we don't have to worry about possible bit 12 aliasing.
* XXXKW is it worth turning on KX and using hit ops with xkphys?
*/
static inline void __sb1_writeback_inv_dcache_phys_range(unsigned long start,
unsigned long end)
{
start &= ~(dcache_line_size - 1);
end = (end + dcache_line_size - 1) & ~(dcache_line_size - 1);
while (start != end) {
cache_set_op(Index_Writeback_Inv_D, start & dcache_index_mask);
start += dcache_line_size;
}
sync();
}
/*
* Invalidate the entire icache
*/
static inline void __sb1_flush_icache_all(void)
{
unsigned long addr = 0;
while (addr < icache_line_size * icache_sets) {
cache_set_op(Index_Invalidate_I, addr);
addr += icache_line_size;
}
}
/*
* Flush the icache for a given physical page. Need to writeback the
* dcache first, then invalidate the icache. If the page isn't
* executable, nothing is required.
*/
static void local_sb1_flush_cache_page(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn)
{
int cpu = smp_processor_id();
#ifndef CONFIG_SMP
if (!(vma->vm_flags & VM_EXEC))
return;
#endif
__sb1_writeback_inv_dcache_range(addr, addr + PAGE_SIZE);
/*
* Bumping the ASID is probably cheaper than the flush ...
*/
if (cpu_context(cpu, vma->vm_mm) != 0)
drop_mmu_context(vma->vm_mm, cpu);
}
#ifdef CONFIG_SMP
struct flush_cache_page_args {
struct vm_area_struct *vma;
unsigned long addr;
unsigned long pfn;
};
static void sb1_flush_cache_page_ipi(void *info)
{
struct flush_cache_page_args *args = info;
local_sb1_flush_cache_page(args->vma, args->addr, args->pfn);
}
/* Dirty dcache could be on another CPU, so do the IPIs */
static void sb1_flush_cache_page(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn)
{
struct flush_cache_page_args args;
if (!(vma->vm_flags & VM_EXEC))
return;
addr &= PAGE_MASK;
args.vma = vma;
args.addr = addr;
args.pfn = pfn;
on_each_cpu(sb1_flush_cache_page_ipi, (void *) &args, 1, 1);
}
#else
void sb1_flush_cache_page(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn)
__attribute__((alias("local_sb1_flush_cache_page")));
#endif
/*
* Invalidate a range of the icache. The addresses are virtual, and
* the cache is virtually indexed and tagged. However, we don't
* necessarily have the right ASID context, so use index ops instead
* of hit ops.
*/
static inline void __sb1_flush_icache_range(unsigned long start,
unsigned long end)
{
start &= ~(icache_line_size - 1);
end = (end + icache_line_size - 1) & ~(icache_line_size - 1);
while (start != end) {
cache_set_op(Index_Invalidate_I, start & icache_index_mask);
start += icache_line_size;
}
mispredict();
sync();
}
/*
* Invalidate all caches on this CPU
*/
static void __attribute_used__ local_sb1___flush_cache_all(void)
{
__sb1_writeback_inv_dcache_all();
__sb1_flush_icache_all();
}
#ifdef CONFIG_SMP
void sb1___flush_cache_all_ipi(void *ignored)
__attribute__((alias("local_sb1___flush_cache_all")));
static void sb1___flush_cache_all(void)
{
on_each_cpu(sb1___flush_cache_all_ipi, 0, 1, 1);
}
#else
void sb1___flush_cache_all(void)
__attribute__((alias("local_sb1___flush_cache_all")));
#endif
/*
* When flushing a range in the icache, we have to first writeback
* the dcache for the same range, so new ifetches will see any
* data that was dirty in the dcache.
*
* The start/end arguments are Kseg addresses (possibly mapped Kseg).
*/
static void local_sb1_flush_icache_range(unsigned long start,
unsigned long end)
{
/* Just wb-inv the whole dcache if the range is big enough */
if ((end - start) > dcache_range_cutoff)
__sb1_writeback_inv_dcache_all();
else
__sb1_writeback_inv_dcache_range(start, end);
/* Just flush the whole icache if the range is big enough */
if ((end - start) > icache_range_cutoff)
__sb1_flush_icache_all();
else
__sb1_flush_icache_range(start, end);
}
#ifdef CONFIG_SMP
struct flush_icache_range_args {
unsigned long start;
unsigned long end;
};
static void sb1_flush_icache_range_ipi(void *info)
{
struct flush_icache_range_args *args = info;
local_sb1_flush_icache_range(args->start, args->end);
}
void sb1_flush_icache_range(unsigned long start, unsigned long end)
{
struct flush_icache_range_args args;
args.start = start;
args.end = end;
on_each_cpu(sb1_flush_icache_range_ipi, &args, 1, 1);
}
#else
void sb1_flush_icache_range(unsigned long start, unsigned long end)
__attribute__((alias("local_sb1_flush_icache_range")));
#endif
/*
* Flush the icache for a given physical page. Need to writeback the
* dcache first, then invalidate the icache. If the page isn't
* executable, nothing is required.
*/
static void local_sb1_flush_icache_page(struct vm_area_struct *vma,
struct page *page)
{
unsigned long start;
int cpu = smp_processor_id();
#ifndef CONFIG_SMP
if (!(vma->vm_flags & VM_EXEC))
return;
#endif
/* Need to writeback any dirty data for that page, we have the PA */
start = (unsigned long)(page-mem_map) << PAGE_SHIFT;
__sb1_writeback_inv_dcache_phys_range(start, start + PAGE_SIZE);
/*
* If there's a context, bump the ASID (cheaper than a flush,
* since we don't know VAs!)
*/
if (cpu_context(cpu, vma->vm_mm) != 0) {
drop_mmu_context(vma->vm_mm, cpu);
}
}
#ifdef CONFIG_SMP
struct flush_icache_page_args {
struct vm_area_struct *vma;
struct page *page;
};
static void sb1_flush_icache_page_ipi(void *info)
{
struct flush_icache_page_args *args = info;
local_sb1_flush_icache_page(args->vma, args->page);
}
/* Dirty dcache could be on another CPU, so do the IPIs */
static void sb1_flush_icache_page(struct vm_area_struct *vma,
struct page *page)
{
struct flush_icache_page_args args;
if (!(vma->vm_flags & VM_EXEC))
return;
args.vma = vma;
args.page = page;
on_each_cpu(sb1_flush_icache_page_ipi, (void *) &args, 1, 1);
}
#else
void sb1_flush_icache_page(struct vm_area_struct *vma, struct page *page)
__attribute__((alias("local_sb1_flush_icache_page")));
#endif
/*
* A signal trampoline must fit into a single cacheline.
*/
static void local_sb1_flush_cache_sigtramp(unsigned long addr)
{
cache_set_op(Index_Writeback_Inv_D, addr & dcache_index_mask);
cache_set_op(Index_Writeback_Inv_D, (addr ^ (1<<12)) & dcache_index_mask);
cache_set_op(Index_Invalidate_I, addr & icache_index_mask);
mispredict();
}
#ifdef CONFIG_SMP
static void sb1_flush_cache_sigtramp_ipi(void *info)
{
unsigned long iaddr = (unsigned long) info;
local_sb1_flush_cache_sigtramp(iaddr);
}
static void sb1_flush_cache_sigtramp(unsigned long addr)
{
on_each_cpu(sb1_flush_cache_sigtramp_ipi, (void *) addr, 1, 1);
}
#else
void sb1_flush_cache_sigtramp(unsigned long addr)
__attribute__((alias("local_sb1_flush_cache_sigtramp")));
#endif
/*
* Anything that just flushes dcache state can be ignored, as we're always
* coherent in dcache space. This is just a dummy function that all the
* nop'ed routines point to
*/
static void sb1_nop(void)
{
}
/*
* Cache set values (from the mips64 spec)
* 0 - 64
* 1 - 128
* 2 - 256
* 3 - 512
* 4 - 1024
* 5 - 2048
* 6 - 4096
* 7 - Reserved
*/
static unsigned int decode_cache_sets(unsigned int config_field)
{
if (config_field == 7) {
/* JDCXXX - Find a graceful way to abort. */
return 0;
}
return (1<<(config_field + 6));
}
/*
* Cache line size values (from the mips64 spec)
* 0 - No cache present.
* 1 - 4 bytes
* 2 - 8 bytes
* 3 - 16 bytes
* 4 - 32 bytes
* 5 - 64 bytes
* 6 - 128 bytes
* 7 - Reserved
*/
static unsigned int decode_cache_line_size(unsigned int config_field)
{
if (config_field == 0) {
return 0;
} else if (config_field == 7) {
/* JDCXXX - Find a graceful way to abort. */
return 0;
}
return (1<<(config_field + 1));
}
/*
* Relevant bits of the config1 register format (from the MIPS32/MIPS64 specs)
*
* 24:22 Icache sets per way
* 21:19 Icache line size
* 18:16 Icache Associativity
* 15:13 Dcache sets per way
* 12:10 Dcache line size
* 9:7 Dcache Associativity
*/
static char *way_string[] = {
"direct mapped", "2-way", "3-way", "4-way",
"5-way", "6-way", "7-way", "8-way",
};
static __init void probe_cache_sizes(void)
{
u32 config1;
config1 = read_c0_config1();
icache_line_size = decode_cache_line_size((config1 >> 19) & 0x7);
dcache_line_size = decode_cache_line_size((config1 >> 10) & 0x7);
icache_sets = decode_cache_sets((config1 >> 22) & 0x7);
dcache_sets = decode_cache_sets((config1 >> 13) & 0x7);
icache_assoc = ((config1 >> 16) & 0x7) + 1;
dcache_assoc = ((config1 >> 7) & 0x7) + 1;
icache_size = icache_line_size * icache_sets * icache_assoc;
dcache_size = dcache_line_size * dcache_sets * dcache_assoc;
/* Need to remove non-index bits for index ops */
icache_index_mask = (icache_sets - 1) * icache_line_size;
dcache_index_mask = (dcache_sets - 1) * dcache_line_size;
/*
* These are for choosing range (index ops) versus all.
* icache flushes all ways for each set, so drop icache_assoc.
* dcache flushes all ways and each setting of bit 12 for each
* index, so drop dcache_assoc and halve the dcache_sets.
*/
icache_range_cutoff = icache_sets * icache_line_size;
dcache_range_cutoff = (dcache_sets / 2) * icache_line_size;
printk("Primary instruction cache %ldkB, %s, linesize %d bytes.\n",
icache_size >> 10, way_string[icache_assoc - 1],
icache_line_size);
printk("Primary data cache %ldkB, %s, linesize %d bytes.\n",
dcache_size >> 10, way_string[dcache_assoc - 1],
dcache_line_size);
}
/*
* This is called from cache.c. We have to set up all the
* memory management function pointers, as well as initialize
* the caches and tlbs
*/
void sb1_cache_init(void)
{
extern char except_vec2_sb1;
extern char handle_vec2_sb1;
/* Special cache error handler for SB1 */
set_uncached_handler (0x100, &except_vec2_sb1, 0x80);
probe_cache_sizes();
#ifdef CONFIG_SIBYTE_DMA_PAGEOPS
sb1_dma_init();
#endif
/*
* None of these are needed for the SB1 - the Dcache is
* physically indexed and tagged, so no virtual aliasing can
* occur
*/
flush_cache_range = (void *) sb1_nop;
flush_cache_mm = (void (*)(struct mm_struct *))sb1_nop;
flush_cache_all = sb1_nop;
/* These routines are for Icache coherence with the Dcache */
flush_icache_range = sb1_flush_icache_range;
flush_icache_page = sb1_flush_icache_page;
flush_icache_all = __sb1_flush_icache_all; /* local only */
/* This implies an Icache flush too, so can't be nop'ed */
flush_cache_page = sb1_flush_cache_page;
flush_cache_sigtramp = sb1_flush_cache_sigtramp;
local_flush_data_cache_page = (void *) sb1_nop;
flush_data_cache_page = (void *) sb1_nop;
/* Full flush */
__flush_cache_all = sb1___flush_cache_all;
change_c0_config(CONF_CM_CMASK, CONF_CM_DEFAULT);
/*
* This is the only way to force the update of K0 to complete
* before subsequent instruction fetch.
*/
__asm__ __volatile__(
".set push \n"
" .set noat \n"
" .set noreorder \n"
" .set mips3 \n"
" " STR(PTR_LA) " $1, 1f \n"
" " STR(MTC0) " $1, $14 \n"
" eret \n"
"1: .set pop"
:
:
: "memory");
flush_cache_all();
}