r4xx0.c

上传linux-jx2410的源代码

#endif
		__save_and_cli(flags);
		size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
		size = (size + 1) >> 1;
		if(size <= mips_cpu.tlbsize/2) {
			int oldpid = (get_entryhi() & 0xff);
			int newpid = (mm->context & 0xff);

			start &= (PAGE_MASK << 1);
			end += ((PAGE_SIZE << 1) - 1);
			end &= (PAGE_MASK << 1);
			while(start < end) {
				int idx;

				set_entryhi(start | newpid);
				start += (PAGE_SIZE << 1);
				BARRIER;
				tlb_probe();
				BARRIER;
				idx = get_index();
				set_entrylo0(0);
				set_entrylo1(0);
				set_entryhi(KSEG0);
				BARRIER;
				if(idx < 0)
					continue;
				tlb_write_indexed();
				BARRIER;
			}
			set_entryhi(oldpid);
		} else {
			get_new_mmu_context(mm, asid_cache);
			if (mm == current->active_mm)
				set_entryhi(mm->context & 0xff);
		}
		__restore_flags(flags);
	}
}

void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
{
	if (vma->vm_mm->context != 0) {
		unsigned long flags;
		int oldpid, newpid, idx;

#ifdef DEBUG_TLB
		printk("[tlbpage<%d,%08lx>]", vma->vm_mm->context, page);
#endif
		newpid = (vma->vm_mm->context & 0xff);
		page &= (PAGE_MASK << 1);
		__save_and_cli(flags);
		oldpid = (get_entryhi() & 0xff);
		set_entryhi(page | newpid);
		BARRIER;
		tlb_probe();
		BARRIER;
		idx = get_index();
		set_entrylo0(0);
		set_entrylo1(0);
		set_entryhi(KSEG0);
		if(idx < 0)
			goto finish;
		BARRIER;
		tlb_write_indexed();

	finish:
		BARRIER;
		set_entryhi(oldpid);
		__restore_flags(flags);
	}
}

void pgd_init(unsigned long page)
{
	unsigned long *p = (unsigned long *) page;
	int i;

	for(i = 0; i < USER_PTRS_PER_PGD; i+=8) {
		p[i + 0] = (unsigned long) invalid_pte_table;
		p[i + 1] = (unsigned long) invalid_pte_table;
		p[i + 2] = (unsigned long) invalid_pte_table;
		p[i + 3] = (unsigned long) invalid_pte_table;
		p[i + 4] = (unsigned long) invalid_pte_table;
		p[i + 5] = (unsigned long) invalid_pte_table;
		p[i + 6] = (unsigned long) invalid_pte_table;
		p[i + 7] = (unsigned long) invalid_pte_table;
	}
}

/* We will need multiple versions of update_mmu_cache(), one that just
 * updates the TLB with the new pte(s), and another which also checks
 * for the R4k "end of page" hardware bug and does the needy.
 */
void update_mmu_cache(struct vm_area_struct * vma,
				 unsigned long address, pte_t pte)
{
	unsigned long flags;
	pgd_t *pgdp;
	pmd_t *pmdp;
	pte_t *ptep;
	int idx, pid;

	/*
	 * Handle debugger faulting in for debugee.
	 */
	if (current->active_mm != vma->vm_mm)
		return;

	pid = get_entryhi() & 0xff;

#ifdef DEBUG_TLB
	if((pid != (vma->vm_mm->context & 0xff)) || (vma->vm_mm->context == 0)) {
		printk("update_mmu_cache: Wheee, bogus tlbpid mmpid=%d tlbpid=%d\n",
		       (int) (vma->vm_mm->context & 0xff), pid);
	}
#endif

	__save_and_cli(flags);
	address &= (PAGE_MASK << 1);
	set_entryhi(address | (pid));
	pgdp = pgd_offset(vma->vm_mm, address);
	BARRIER;
	tlb_probe();
	BARRIER;
	pmdp = pmd_offset(pgdp, address);
	idx = get_index();
	ptep = pte_offset(pmdp, address);
	BARRIER;
	set_entrylo0(pte_val(*ptep++) >> 6);
	set_entrylo1(pte_val(*ptep) >> 6);
	set_entryhi(address | (pid));
	BARRIER;
	if(idx < 0) {
		tlb_write_random();
	} else {
		tlb_write_indexed();
	}
	BARRIER;
	set_entryhi(pid);
	BARRIER;
	__restore_flags(flags);
}

#if 0
static void r4k_update_mmu_cache_hwbug(struct vm_area_struct * vma,
				       unsigned long address, pte_t pte)
{
	unsigned long flags;
	pgd_t *pgdp;
	pmd_t *pmdp;
	pte_t *ptep;
	int idx;

	__save_and_cli(flags);
	address &= (PAGE_MASK << 1);
	set_entryhi(address | (get_entryhi() & 0xff));
	pgdp = pgd_offset(vma->vm_mm, address);
	tlb_probe();
	pmdp = pmd_offset(pgdp, address);
	idx = get_index();
	ptep = pte_offset(pmdp, address);
	set_entrylo0(pte_val(*ptep++) >> 6);
	set_entrylo1(pte_val(*ptep) >> 6);
	BARRIER;
	if(idx < 0)
		tlb_write_random();
	else
		tlb_write_indexed();
	BARRIER;
	__restore_flags(flags);
}
#endif

void show_regs(struct pt_regs * regs)
{
	/* Saved main processor registers. */
	printk("$0 : %08lx %08lx %08lx %08lx\n",
	       0UL, regs->regs[1], regs->regs[2], regs->regs[3]);
	printk("$4 : %08lx %08lx %08lx %08lx\n",
               regs->regs[4], regs->regs[5], regs->regs[6], regs->regs[7]);
	printk("$8 : %08lx %08lx %08lx %08lx\n",
	       regs->regs[8], regs->regs[9], regs->regs[10], regs->regs[11]);
	printk("$12: %08lx %08lx %08lx %08lx\n",
               regs->regs[12], regs->regs[13], regs->regs[14], regs->regs[15]);
	printk("$16: %08lx %08lx %08lx %08lx\n",
	       regs->regs[16], regs->regs[17], regs->regs[18], regs->regs[19]);
	printk("$20: %08lx %08lx %08lx %08lx\n",
               regs->regs[20], regs->regs[21], regs->regs[22], regs->regs[23]);
	printk("$24: %08lx %08lx\n",
	       regs->regs[24], regs->regs[25]);
	printk("$28: %08lx %08lx %08lx %08lx\n",
	       regs->regs[28], regs->regs[29], regs->regs[30], regs->regs[31]);

	/* Saved cp0 registers. */
	printk("epc   : %08lx    %s\nStatus: %08lx\nCause : %08lx\n",
	       regs->cp0_epc, print_tainted(), regs->cp0_status, regs->cp0_cause);
}
			
void add_wired_entry(unsigned long entrylo0, unsigned long entrylo1,
				      unsigned long entryhi, unsigned long pagemask)
{
        unsigned long flags;
        unsigned long wired;
        unsigned long old_pagemask;
        unsigned long old_ctx;

        __save_and_cli(flags);
        /* Save old context and create impossible VPN2 value */
        old_ctx = (get_entryhi() & 0xff);
        old_pagemask = get_pagemask();
        wired = get_wired();
        set_wired (wired + 1);
        set_index (wired);
        BARRIER;    
        set_pagemask (pagemask);
        set_entryhi(entryhi);
        set_entrylo0(entrylo0);
        set_entrylo1(entrylo1);
        BARRIER;    
        tlb_write_indexed();
        BARRIER;    
    
        set_entryhi(old_ctx);
        BARRIER;    
        set_pagemask (old_pagemask);
        flush_tlb_all();    
        __restore_flags(flags);
}

/* Detect and size the various r4k caches. */
static void __init probe_icache(unsigned long config)
{
        switch (mips_cpu.cputype) {
        case CPU_VR41XX:
                icache_size = 1 << (10 + ((config >> 9) & 7));
                break;
        default:
                icache_size = 1 << (12 + ((config >> 9) & 7));
                break;
        }
	ic_lsize = 16 << ((config >> 5) & 1);

	printk("Primary instruction cache %dkb, linesize %d bytes.\n",
	       icache_size >> 10, ic_lsize);
}

static void __init probe_dcache(unsigned long config)
{
        switch (mips_cpu.cputype) {
        case CPU_VR41XX:
                dcache_size = 1 << (10 + ((config >> 6) & 7));
                break;
        default:
                dcache_size = 1 << (12 + ((config >> 6) & 7));
                break;
        }
	dc_lsize = 16 << ((config >> 4) & 1);

	printk("Primary data cache %dkb, linesize %d bytes.\n",
	       dcache_size >> 10, dc_lsize);
}


/* If you even _breathe_ on this function, look at the gcc output
 * and make sure it does not pop things on and off the stack for
 * the cache sizing loop that executes in KSEG1 space or else
 * you will crash and burn badly.  You have been warned.
 */
static int __init probe_scache(unsigned long config)
{
	extern unsigned long stext;
	unsigned long flags, addr, begin, end, pow2;
	int tmp;

	tmp = ((config >> 17) & 1);
	if(tmp)
		return 0;
	tmp = ((config >> 22) & 3);
	switch(tmp) {
	case 0:
		sc_lsize = 16;
		break;
	case 1:
		sc_lsize = 32;
		break;
	case 2:
		sc_lsize = 64;
		break;
	case 3:
		sc_lsize = 128;
		break;
	}

	begin = (unsigned long) &stext;
	begin &= ~((4 * 1024 * 1024) - 1);
	end = begin + (4 * 1024 * 1024);

	/* This is such a bitch, you'd think they would make it
	 * easy to do this.  Away you daemons of stupidity!
	 */
	__save_and_cli(flags);

	/* Fill each size-multiple cache line with a valid tag. */
	pow2 = (64 * 1024);
	for(addr = begin; addr < end; addr = (begin + pow2)) {
		unsigned long *p = (unsigned long *) addr;
		__asm__ __volatile__("nop" : : "r" (*p)); /* whee... */
		pow2 <<= 1;
	}

	/* Load first line with zero (therefore invalid) tag. */
	set_taglo(0);
	set_taghi(0);
	__asm__ __volatile__("nop; nop; nop; nop;"); /* avoid the hazard */
	__asm__ __volatile__("\n\t.set noreorder\n\t"
			     ".set mips3\n\t"
			     "cache 8, (%0)\n\t"
			     ".set mips0\n\t"
			     ".set reorder\n\t" : : "r" (begin));
	__asm__ __volatile__("\n\t.set noreorder\n\t"
			     ".set mips3\n\t"
			     "cache 9, (%0)\n\t"
			     ".set mips0\n\t"
			     ".set reorder\n\t" : : "r" (begin));
	__asm__ __volatile__("\n\t.set noreorder\n\t"
			     ".set mips3\n\t"
			     "cache 11, (%0)\n\t"
			     ".set mips0\n\t"
			     ".set reorder\n\t" : : "r" (begin));

	/* Now search for the wrap around point. */
	pow2 = (128 * 1024);
	tmp = 0;
	for(addr = (begin + (128 * 1024)); addr < (end); addr = (begin + pow2)) {
		__asm__ __volatile__("\n\t.set noreorder\n\t"
				     ".set mips3\n\t"
				     "cache 7, (%0)\n\t"
				     ".set mips0\n\t"
				     ".set reorder\n\t" : : "r" (addr));
		__asm__ __volatile__("nop; nop; nop; nop;"); /* hazard... */
		if(!get_taglo())
			break;
		pow2 <<= 1;
	}
	__restore_flags(flags);
	addr -= begin;
	printk("Secondary cache sized at %dK linesize %d bytes.\n",
	       (int) (addr >> 10), sc_lsize);
	scache_size = addr;
	return 1;
}

static void __init setup_noscache_funcs(void)
{
	unsigned int prid;

	switch(dc_lsize) {
	case 16:
		_clear_page = r4k_clear_page_d16;
		_copy_page = r4k_copy_page_d16;
		_flush_cache_all = r4k_flush_cache_all_d16i16;
		_flush_cache_mm = r4k_flush_cache_mm_d16i16;
		_flush_cache_range = r4k_flush_cache_range_d16i16;
		_flush_cache_page = r4k_flush_cache_page_d16i16;
		_flush_page_to_ram = r4k_flush_page_to_ram_d16;
		break;
	case 32:
		prid = read_32bit_cp0_register(CP0_PRID) & 0xfff0;
		if (prid == 0x2010) {			/* R4600 V1.7 */
			_clear_page = r4k_clear_page_r4600_v1;
			_copy_page = r4k_copy_page_r4600_v1;
			_flush_page_to_ram = r4k_flush_page_to_ram_d32_r4600;
		} else if (prid == 0x2020) {		/* R4600 V2.0 */
			_clear_page = r4k_clear_page_r4600_v2;
			_copy_page = r4k_copy_page_r4600_v2;
			_flush_page_to_ram = r4k_flush_page_to_ram_d32;
		} else {
			_clear_page = r4k_clear_page_d32;
			_copy_page = r4k_copy_page_d32;
			_flush_page_to_ram = r4k_flush_page_to_ram_d32;
		}
		_flush_cache_all = r4k_flush_cache_all_d32i32;
		_flush_cache_mm = r4k_flush_cache_mm_d32i32;
		_flush_cache_range = r4k_flush_cache_range_d32i32;
		_flush_cache_page = r4k_flush_cache_page_d32i32;
		break;
	}
	___flush_cache_all = _flush_cache_all;

	_flush_icache_page = r4k_flush_icache_page_p;

	_dma_cache_wback_inv = r4k_dma_cache_wback_inv_pc;
	_dma_cache_wback = r4k_dma_cache_wback;
	_dma_cache_inv = r4k_dma_cache_inv_pc;
}

static void __init setup_scache_funcs(void)
{
	switch(sc_lsize) {
	case 16:
		switch(dc_lsize) {
		case 16:
			_flush_cache_all = r4k_flush_cache_all_s16d16i16;
			_flush_cache_mm = r4k_flush_cache_mm_s16d16i16;
			_flush_cache_range = r4k_flush_cache_range_s16d16i16;
			_flush_cache_page = r4k_flush_cache_page_s16d16i16;
			break;
		case 32:
			panic("Invalid cache configuration detected");
		};
		_flush_page_to_ram = r4k_flush_page_to_ram_s16;
		_clear_page = r4k_clear_page_s16;
		_copy_page = r4k_copy_page_s16;
		break;
	case 32:
		switch(dc_lsize) {
		case 16:
			_flush_cache_all = r4k_flush_cache_all_s32d16i16;
			_flush_cache_mm = r4k_flush_cache_mm_s32d16i16;
			_flush_cache_range = r4k_flush_cache_range_s32d16i16;
			_flush_cache_page = r4k_flush_cache_page_s32d16i16;
			break;
		case 32:
			_flush_cache_all = r4k_flush_cache_all_s32d32i32;
			_flush_cache_mm = r4k_flush_cache_mm_s32d32i32;
			_flush_cache_range = r4k_flush_cache_range_s32d32i32;
			_flush_cache_page = r4k_flush_cache_page_s32d32i32;
			break;
		};
		_flush_page_to_ram = r4k_flush_page_to_ram_s32;
		_clear_page = r4k_clear_page_s32;
		_copy_page = r4k_copy_page_s32;
		break;
	case 64:
		switch(dc_lsize) {
		case 16:
			_flush_cache_all = r4k_flush_cache_all_s64d16i16;
			_flush_cache_mm = r4k_flush_cache_mm_s64d16i16;
			_flush_cache_range = r4k_flush_cache_range_s64d16i16;
			_flush_cache_page = r4k_flush_cache_page_s64d16i16;
			break;
		case 32:
			_flush_cache_all = r4k_flush_cache_all_s64d32i32;
			_flush_cache_mm = r4k_flush_cache_mm_s64d32i32;
			_flush_cache_range = r4k_flush_cache_range_s64d32i32;
			_flush_cache_page = r4k_flush_cache_page_s64d32i32;
			break;
		};
		_flush_page_to_ram = r4k_flush_page_to_ram_s64;
		_clear_page = r4k_clear_page_s64;
		_copy_page = r4k_copy_page_s64;
		break;
	case 128:
		switch(dc_lsize) {
		case 16:
			_flush_cache_all = r4k_flush_cache_all_s128d16i16;
			_flush_cache_mm = r4k_flush_cache_mm_s128d16i16;
			_flush_cache_range = r4k_flush_cache_range_s128d16i16;
			_flush_cache_page = r4k_flush_cache_page_s128d16i16;
			break;
		case 32:
			_flush_cache_all = r4k_flush_cache_all_s128d32i32;
			_flush_cache_mm = r4k_flush_cache_mm_s128d32i32;
			_flush_cache_range = r4k_flush_cache_range_s128d32i32;
			_flush_cache_page = r4k_flush_cache_page_s128d32i32;
			break;
		};
		_flush_page_to_ram = r4k_flush_page_to_ram_s128;
		_clear_page = r4k_clear_page_s128;
		_copy_page = r4k_copy_page_s128;
		break;
	}
	___flush_cache_all = _flush_cache_all;
	_flush_icache_page = r4k_flush_icache_page_s;
	_dma_cache_wback_inv = r4k_dma_cache_wback_inv_sc;
	_dma_cache_wback = r4k_dma_cache_wback;
	_dma_cache_inv = r4k_dma_cache_inv_sc;
}

typedef int (*probe_func_t)(unsigned long);

static inline void __init setup_scache(unsigned int config)
{
	probe_func_t probe_scache_kseg1;
	int sc_present = 0;

	/* Maybe the cpu knows about a l2 cache? */
	probe_scache_kseg1 = (probe_func_t) (KSEG1ADDR(&probe_scache));
	sc_present = probe_scache_kseg1(config);

	if (sc_present) {
		setup_scache_funcs();
		return;
	}

	setup_noscache_funcs();
}

void __init ld_mmu_r4xx0(void)
{
	unsigned long config = read_32bit_cp0_register(CP0_CONFIG);

	printk("CPU revision is: %08x\n", read_32bit_cp0_register(CP0_PRID));

#ifdef CONFIG_MIPS_UNCACHED
	change_cp0_config(CONF_CM_CMASK, CONF_CM_UNCACHED);
#else
	change_cp0_config(CONF_CM_CMASK, CONF_CM_CACHABLE_NONCOHERENT);
#endif

	probe_icache(config);
	probe_dcache(config);
	setup_scache(config);

	switch(mips_cpu.cputype) {
	case CPU_R4600:			/* QED style two way caches? */
	case CPU_R4700:
	case CPU_R5000:
	case CPU_NEVADA:
		_flush_cache_page = r4k_flush_cache_page_d32i32_r4600;
	}

	_flush_cache_sigtramp = r4k_flush_cache_sigtramp;
	_flush_icache_range = r4k_flush_icache_range;	/* Ouch */
	if ((read_32bit_cp0_register(CP0_PRID) & 0xfff0) == 0x2020) {
		_flush_cache_sigtramp = r4600v20k_flush_cache_sigtramp;
	}

	__flush_cache_all();
	write_32bit_cp0_register(CP0_WIRED, 0);

	/*
	 * You should never change this register:
	 *   - On R4600 1.7 the tlbp never hits for pages smaller than
	 *     the value in the c0_pagemask register.
	 *   - The entire mm handling assumes the c0_pagemask register to
	 *     be set for 4kb pages.
	 */
	set_pagemask(PM_4K);
	flush_tlb_all();
}