c-r4k.c

linux 内核源代码

/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1996 David S. Miller ([e-mail])
 * Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Ralf Baechle ([e-mail])
 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
 */
#include <linux/hardirq.h>
#include <linux/init.h>
#include <linux/highmem.h>
#include <linux/kernel.h>
#include <linux/linkage.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/bitops.h>

#include <asm/bcache.h>
#include <asm/bootinfo.h>
#include <asm/cache.h>
#include <asm/cacheops.h>
#include <asm/cpu.h>
#include <asm/cpu-features.h>
#include <asm/io.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/r4kcache.h>
#include <asm/sections.h>
#include <asm/system.h>
#include <asm/mmu_context.h>
#include <asm/war.h>
#include <asm/cacheflush.h> /* for run_uncached() */


/*
 * Special Variant of smp_call_function for use by cache functions:
 *
 *  o No return value
 *  o collapses to normal function call on UP kernels
 *  o collapses to normal function call on systems with a single shared
 *    primary cache.
 */
static inline void r4k_on_each_cpu(void (*func) (void *info), void *info,
                                   int retry, int wait)
{
	preempt_disable();

#if !defined(CONFIG_MIPS_MT_SMP) && !defined(CONFIG_MIPS_MT_SMTC)
	smp_call_function(func, info, retry, wait);
#endif
	func(info);
	preempt_enable();
}

/*
 * Must die.
 */
static unsigned long icache_size __read_mostly;
static unsigned long dcache_size __read_mostly;
static unsigned long scache_size __read_mostly;

/*
 * Dummy cache handling routines for machines without boardcaches
 */
static void cache_noop(void) {}

static struct bcache_ops no_sc_ops = {
	.bc_enable = (void *)cache_noop,
	.bc_disable = (void *)cache_noop,
	.bc_wback_inv = (void *)cache_noop,
	.bc_inv = (void *)cache_noop
};

struct bcache_ops *bcops = &no_sc_ops;

#define cpu_is_r4600_v1_x()	((read_c0_prid() & 0xfffffff0) == 0x00002010)
#define cpu_is_r4600_v2_x()	((read_c0_prid() & 0xfffffff0) == 0x00002020)

#define R4600_HIT_CACHEOP_WAR_IMPL					\
do {									\
	if (R4600_V2_HIT_CACHEOP_WAR && cpu_is_r4600_v2_x())		\
		*(volatile unsigned long *)CKSEG1;			\
	if (R4600_V1_HIT_CACHEOP_WAR)					\
		__asm__ __volatile__("nop;nop;nop;nop");		\
} while (0)

static void (*r4k_blast_dcache_page)(unsigned long addr);

static inline void r4k_blast_dcache_page_dc32(unsigned long addr)
{
	R4600_HIT_CACHEOP_WAR_IMPL;
	blast_dcache32_page(addr);
}

static void __init r4k_blast_dcache_page_setup(void)
{
	unsigned long  dc_lsize = cpu_dcache_line_size();

	if (dc_lsize == 0)
		r4k_blast_dcache_page = (void *)cache_noop;
	else if (dc_lsize == 16)
		r4k_blast_dcache_page = blast_dcache16_page;
	else if (dc_lsize == 32)
		r4k_blast_dcache_page = r4k_blast_dcache_page_dc32;
}

static void (* r4k_blast_dcache_page_indexed)(unsigned long addr);

static void __init r4k_blast_dcache_page_indexed_setup(void)
{
	unsigned long dc_lsize = cpu_dcache_line_size();

	if (dc_lsize == 0)
		r4k_blast_dcache_page_indexed = (void *)cache_noop;
	else if (dc_lsize == 16)
		r4k_blast_dcache_page_indexed = blast_dcache16_page_indexed;
	else if (dc_lsize == 32)
		r4k_blast_dcache_page_indexed = blast_dcache32_page_indexed;
}

static void (* r4k_blast_dcache)(void);

static void __init r4k_blast_dcache_setup(void)
{
	unsigned long dc_lsize = cpu_dcache_line_size();

	if (dc_lsize == 0)
		r4k_blast_dcache = (void *)cache_noop;
	else if (dc_lsize == 16)
		r4k_blast_dcache = blast_dcache16;
	else if (dc_lsize == 32)
		r4k_blast_dcache = blast_dcache32;
}

/* force code alignment (used for TX49XX_ICACHE_INDEX_INV_WAR) */
#define JUMP_TO_ALIGN(order) \
	__asm__ __volatile__( \
		"b\t1f\n\t" \
		".align\t" #order "\n\t" \
		"1:\n\t" \
		)
#define CACHE32_UNROLL32_ALIGN	JUMP_TO_ALIGN(10) /* 32 * 32 = 1024 */
#define CACHE32_UNROLL32_ALIGN2	JUMP_TO_ALIGN(11)

static inline void blast_r4600_v1_icache32(void)
{
	unsigned long flags;

	local_irq_save(flags);
	blast_icache32();
	local_irq_restore(flags);
}

static inline void tx49_blast_icache32(void)
{
	unsigned long start = INDEX_BASE;
	unsigned long end = start + current_cpu_data.icache.waysize;
	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
	unsigned long ws_end = current_cpu_data.icache.ways <<
	                       current_cpu_data.icache.waybit;
	unsigned long ws, addr;

	CACHE32_UNROLL32_ALIGN2;
	/* I'm in even chunk.  blast odd chunks */
	for (ws = 0; ws < ws_end; ws += ws_inc)
		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
			cache32_unroll32(addr|ws, Index_Invalidate_I);
	CACHE32_UNROLL32_ALIGN;
	/* I'm in odd chunk.  blast even chunks */
	for (ws = 0; ws < ws_end; ws += ws_inc)
		for (addr = start; addr < end; addr += 0x400 * 2)
			cache32_unroll32(addr|ws, Index_Invalidate_I);
}

static inline void blast_icache32_r4600_v1_page_indexed(unsigned long page)
{
	unsigned long flags;

	local_irq_save(flags);
	blast_icache32_page_indexed(page);
	local_irq_restore(flags);
}

static inline void tx49_blast_icache32_page_indexed(unsigned long page)
{
	unsigned long indexmask = current_cpu_data.icache.waysize - 1;
	unsigned long start = INDEX_BASE + (page & indexmask);
	unsigned long end = start + PAGE_SIZE;
	unsigned long ws_inc = 1UL << current_cpu_data.icache.waybit;
	unsigned long ws_end = current_cpu_data.icache.ways <<
	                       current_cpu_data.icache.waybit;
	unsigned long ws, addr;

	CACHE32_UNROLL32_ALIGN2;
	/* I'm in even chunk.  blast odd chunks */
	for (ws = 0; ws < ws_end; ws += ws_inc)
		for (addr = start + 0x400; addr < end; addr += 0x400 * 2)
			cache32_unroll32(addr|ws, Index_Invalidate_I);
	CACHE32_UNROLL32_ALIGN;
	/* I'm in odd chunk.  blast even chunks */
	for (ws = 0; ws < ws_end; ws += ws_inc)
		for (addr = start; addr < end; addr += 0x400 * 2)
			cache32_unroll32(addr|ws, Index_Invalidate_I);
}

static void (* r4k_blast_icache_page)(unsigned long addr);

static void __init r4k_blast_icache_page_setup(void)
{
	unsigned long ic_lsize = cpu_icache_line_size();

	if (ic_lsize == 0)
		r4k_blast_icache_page = (void *)cache_noop;
	else if (ic_lsize == 16)
		r4k_blast_icache_page = blast_icache16_page;
	else if (ic_lsize == 32)
		r4k_blast_icache_page = blast_icache32_page;
	else if (ic_lsize == 64)
		r4k_blast_icache_page = blast_icache64_page;
}


static void (* r4k_blast_icache_page_indexed)(unsigned long addr);

static void __init r4k_blast_icache_page_indexed_setup(void)
{
	unsigned long ic_lsize = cpu_icache_line_size();

	if (ic_lsize == 0)
		r4k_blast_icache_page_indexed = (void *)cache_noop;
	else if (ic_lsize == 16)
		r4k_blast_icache_page_indexed = blast_icache16_page_indexed;
	else if (ic_lsize == 32) {
		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
			r4k_blast_icache_page_indexed =
				blast_icache32_r4600_v1_page_indexed;
		else if (TX49XX_ICACHE_INDEX_INV_WAR)
			r4k_blast_icache_page_indexed =
				tx49_blast_icache32_page_indexed;
		else
			r4k_blast_icache_page_indexed =
				blast_icache32_page_indexed;
	} else if (ic_lsize == 64)
		r4k_blast_icache_page_indexed = blast_icache64_page_indexed;
}

static void (* r4k_blast_icache)(void);

static void __init r4k_blast_icache_setup(void)
{
	unsigned long ic_lsize = cpu_icache_line_size();

	if (ic_lsize == 0)
		r4k_blast_icache = (void *)cache_noop;
	else if (ic_lsize == 16)
		r4k_blast_icache = blast_icache16;
	else if (ic_lsize == 32) {
		if (R4600_V1_INDEX_ICACHEOP_WAR && cpu_is_r4600_v1_x())
			r4k_blast_icache = blast_r4600_v1_icache32;
		else if (TX49XX_ICACHE_INDEX_INV_WAR)
			r4k_blast_icache = tx49_blast_icache32;
		else
			r4k_blast_icache = blast_icache32;
	} else if (ic_lsize == 64)
		r4k_blast_icache = blast_icache64;
}

static void (* r4k_blast_scache_page)(unsigned long addr);

static void __init r4k_blast_scache_page_setup(void)
{
	unsigned long sc_lsize = cpu_scache_line_size();

	if (scache_size == 0)
		r4k_blast_scache_page = (void *)cache_noop;
	else if (sc_lsize == 16)
		r4k_blast_scache_page = blast_scache16_page;
	else if (sc_lsize == 32)
		r4k_blast_scache_page = blast_scache32_page;
	else if (sc_lsize == 64)
		r4k_blast_scache_page = blast_scache64_page;
	else if (sc_lsize == 128)
		r4k_blast_scache_page = blast_scache128_page;
}

static void (* r4k_blast_scache_page_indexed)(unsigned long addr);

static void __init r4k_blast_scache_page_indexed_setup(void)
{
	unsigned long sc_lsize = cpu_scache_line_size();

	if (scache_size == 0)
		r4k_blast_scache_page_indexed = (void *)cache_noop;
	else if (sc_lsize == 16)
		r4k_blast_scache_page_indexed = blast_scache16_page_indexed;
	else if (sc_lsize == 32)
		r4k_blast_scache_page_indexed = blast_scache32_page_indexed;
	else if (sc_lsize == 64)
		r4k_blast_scache_page_indexed = blast_scache64_page_indexed;
	else if (sc_lsize == 128)
		r4k_blast_scache_page_indexed = blast_scache128_page_indexed;
}

static void (* r4k_blast_scache)(void);

static void __init r4k_blast_scache_setup(void)
{
	unsigned long sc_lsize = cpu_scache_line_size();

	if (scache_size == 0)
		r4k_blast_scache = (void *)cache_noop;
	else if (sc_lsize == 16)
		r4k_blast_scache = blast_scache16;
	else if (sc_lsize == 32)
		r4k_blast_scache = blast_scache32;
	else if (sc_lsize == 64)
		r4k_blast_scache = blast_scache64;
	else if (sc_lsize == 128)
		r4k_blast_scache = blast_scache128;
}

static inline void local_r4k___flush_cache_all(void * args)
{
#if defined(CONFIG_CPU_LOONGSON2)
	r4k_blast_scache();
	return;
#endif
	r4k_blast_dcache();
	r4k_blast_icache();

	switch (current_cpu_type()) {
	case CPU_R4000SC:
	case CPU_R4000MC:
	case CPU_R4400SC:
	case CPU_R4400MC:
	case CPU_R10000:
	case CPU_R12000:
	case CPU_R14000:
		r4k_blast_scache();
	}
}

static void r4k___flush_cache_all(void)
{
	r4k_on_each_cpu(local_r4k___flush_cache_all, NULL, 1, 1);
}

static inline int has_valid_asid(const struct mm_struct *mm)
{
#if defined(CONFIG_MIPS_MT_SMP) || defined(CONFIG_MIPS_MT_SMTC)
	int i;

	for_each_online_cpu(i)
		if (cpu_context(i, mm))
			return 1;

	return 0;
#else
	return cpu_context(smp_processor_id(), mm);
#endif
}

static inline void local_r4k_flush_cache_range(void * args)
{
	struct vm_area_struct *vma = args;

	if (!(has_valid_asid(vma->vm_mm)))
		return;

	r4k_blast_dcache();
}

static void r4k_flush_cache_range(struct vm_area_struct *vma,
	unsigned long start, unsigned long end)
{
	if (!cpu_has_dc_aliases)
		return;

	r4k_on_each_cpu(local_r4k_flush_cache_range, vma, 1, 1);
}

static inline void local_r4k_flush_cache_mm(void * args)
{
	struct mm_struct *mm = args;

	if (!has_valid_asid(mm))
		return;

	/*
	 * Kludge alert.  For obscure reasons R4000SC and R4400SC go nuts if we
	 * only flush the primary caches but R10000 and R12000 behave sane ...
	 * R4000SC and R4400SC indexed S-cache ops also invalidate primary
	 * caches, so we can bail out early.
	 */
	if (current_cpu_type() == CPU_R4000SC ||
	    current_cpu_type() == CPU_R4000MC ||
	    current_cpu_type() == CPU_R4400SC ||
	    current_cpu_type() == CPU_R4400MC) {
		r4k_blast_scache();
		return;
	}

	r4k_blast_dcache();
}

static void r4k_flush_cache_mm(struct mm_struct *mm)
{
	if (!cpu_has_dc_aliases)
		return;

	r4k_on_each_cpu(local_r4k_flush_cache_mm, mm, 1, 1);
}

struct flush_cache_page_args {
	struct vm_area_struct *vma;
	unsigned long addr;
	unsigned long pfn;
};

static inline void local_r4k_flush_cache_page(void *args)
{
	struct flush_cache_page_args *fcp_args = args;
	struct vm_area_struct *vma = fcp_args->vma;
	unsigned long addr = fcp_args->addr;
	struct page *page = pfn_to_page(fcp_args->pfn);
	int exec = vma->vm_flags & VM_EXEC;
	struct mm_struct *mm = vma->vm_mm;
	pgd_t *pgdp;
	pud_t *pudp;
	pmd_t *pmdp;
	pte_t *ptep;
	void *vaddr;

	/*
	 * If ownes no valid ASID yet, cannot possibly have gotten
	 * this page into the cache.