patch-2.4.20 linux-2.4.20/arch/mips64/mm/tlb-r4k.c

• Lines: 408
• Date: Thu Nov 28 15:53:10 2002
• Orig file: linux-2.4.19/arch/mips64/mm/tlb-r4k.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.19/arch/mips64/mm/tlb-r4k.c linux-2.4.20/arch/mips64/mm/tlb-r4k.c
@@ -0,0 +1,407 @@
+/*
+ * Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 2002 MIPS Technologies, Inc.  All rights reserved.
+ *
+ * This program is free software; you can distribute it and/or modify it
+ * under the terms of the GNU General Public License (Version 2) as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ * MIPS64 CPU variant specific MMU routines.
+ * These routine are not optimized in any way, they are done in a generic way
+ * so they can be used on all MIPS64 compliant CPUs, and also done in an
+ * attempt not to break anything for the R4xx0 style CPUs.
+ */
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+
+#include <asm/cpu.h>
+#include <asm/bootinfo.h>
+#include <asm/mmu_context.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+
+#undef DEBUG_TLB
+#undef DEBUG_TLBUPDATE
+
+extern char except_vec1_r4k;
+
+/* CP0 hazard avoidance. */
+#define BARRIER __asm__ __volatile__(".set noreorder\n\t" \
+				     "nop; nop; nop; nop; nop; nop;\n\t" \
+				     ".set reorder\n\t")
+
+void local_flush_tlb_all(void)
+{
+	unsigned long flags;
+	unsigned long old_ctx;
+	int entry;
+
+#ifdef DEBUG_TLB
+	printk("[tlball]");
+#endif
+
+	__save_and_cli(flags);
+	/* Save old context and create impossible VPN2 value */
+	old_ctx = (get_entryhi() & 0xff);
+	set_entryhi(KSEG0);
+	set_entrylo0(0);
+	set_entrylo1(0);
+	BARRIER;
+
+	entry = get_wired();
+
+	/* Blast 'em all away. */
+	while(entry < mips_cpu.tlbsize) {
+	        /* Make sure all entries differ. */
+	        set_entryhi(KSEG0+entry*0x2000);
+		set_index(entry);
+		BARRIER;
+		tlb_write_indexed();
+		BARRIER;
+		entry++;
+	}
+	BARRIER;
+	set_entryhi(old_ctx);
+	__restore_flags(flags);
+}
+
+void local_flush_tlb_mm(struct mm_struct *mm)
+{
+	if (CPU_CONTEXT(smp_processor_id(), mm) != 0) {
+		unsigned long flags;
+
+#ifdef DEBUG_TLB
+		printk("[tlbmm<%d>]", mm->context);
+#endif
+		__save_and_cli(flags);
+		get_new_mmu_context(mm, smp_processor_id());
+		if (mm == current->active_mm)
+			set_entryhi(CPU_CONTEXT(smp_processor_id(), mm) &
+				    0xff);
+		__restore_flags(flags);
+	}
+}
+
+void local_flush_tlb_range(struct mm_struct *mm, unsigned long start,
+				unsigned long end)
+{
+	if (CPU_CONTEXT(smp_processor_id(), mm) != 0) {
+		unsigned long flags;
+		int size;
+
+#ifdef DEBUG_TLB
+		printk("[tlbrange<%02x,%08lx,%08lx>]", (mm->context & 0xff),
+		       start, end);
+#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 = (CPU_CONTEXT(smp_processor_id(), mm) &
+				      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);
+				if(idx < 0)
+					continue;
+				/* Make sure all entries differ. */
+				set_entryhi(KSEG0+idx*0x2000);
+				BARRIER;
+				tlb_write_indexed();
+				BARRIER;
+			}
+			set_entryhi(oldpid);
+		} else {
+			get_new_mmu_context(mm, smp_processor_id());
+			if (mm == current->active_mm)
+				set_entryhi(CPU_CONTEXT(smp_processor_id(),
+							mm) & 0xff);
+		}
+		__restore_flags(flags);
+	}
+}
+
+void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
+{
+	if (CPU_CONTEXT(smp_processor_id(), vma->vm_mm) != 0) {
+		unsigned long flags;
+		unsigned long oldpid, newpid, idx;
+
+#ifdef DEBUG_TLB
+		printk("[tlbpage<%d,%08lx>]", vma->vm_mm->context, page);
+#endif
+		newpid = (CPU_CONTEXT(smp_processor_id(), vma->vm_mm) & 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);
+		if(idx < 0)
+			goto finish;
+		/* Make sure all entries differ. */
+		set_entryhi(KSEG0+idx*0x2000);
+		BARRIER;
+		tlb_write_indexed();
+	finish:
+		BARRIER;
+		set_entryhi(oldpid);
+		__restore_flags(flags);
+	}
+}
+
+/*
+ * Updates the TLB with the new pte(s).
+ */
+void mips64_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 != (CPU_CONTEXT(smp_processor_id(), vma->vm_mm) & 0xff)) ||
+	   (CPU_CONTEXT(smp_processor_id(), vma->vm_mm) == 0)) {
+		printk("update_mmu_cache: Wheee, bogus tlbpid mmpid=%d
+			tlbpid=%d\n", (int) (CPU_CONTEXT(smp_processor_id(),
+			vma->vm_mm) & 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);
+}
+
+void dump_mm_page(unsigned long addr)
+{
+	pgd_t	*page_dir, *pgd;
+	pmd_t	*pmd;
+	pte_t	*pte, page;
+	unsigned long val;
+
+	page_dir = pgd_offset(current->mm, 0);
+	pgd = pgd_offset(current->mm, addr);
+	pmd = pmd_offset(pgd, addr);
+	pte = pte_offset(pmd, addr);
+	page = *pte;
+	printk("Memory Mapping: VA = %08x, PA = %08x ", addr, (unsigned int) pte_val(page));
+	val = pte_val(page);
+	if (val & _PAGE_PRESENT) printk("present ");
+	if (val & _PAGE_READ) printk("read ");
+	if (val & _PAGE_WRITE) printk("write ");
+	if (val & _PAGE_ACCESSED) printk("accessed ");
+	if (val & _PAGE_MODIFIED) printk("modified ");
+	if (val & _PAGE_R4KBUG) printk("r4kbug ");
+	if (val & _PAGE_GLOBAL) printk("global ");
+	if (val & _PAGE_VALID) printk("valid ");
+	printk("\n");
+}
+
+void show_tlb(void)
+{
+        unsigned int flags;
+        unsigned int old_ctx;
+	unsigned int entry;
+	unsigned int entrylo0, entrylo1, entryhi;
+
+	__save_and_cli(flags);
+
+	/* Save old context */
+	old_ctx = (get_entryhi() & 0xff);
+
+	printk("TLB content:\n");
+	entry = 0;
+	while(entry < mips_cpu.tlbsize) {
+		set_index(entry);
+		BARRIER;
+		tlb_read();
+		BARRIER;
+		entryhi = get_entryhi();
+		entrylo0 = get_entrylo0();
+		entrylo1 = get_entrylo1();
+		printk("%02d: ASID=%02d%s VA=0x%08x ", entry, entryhi & ASID_MASK, (entrylo0 & entrylo1 & 1) ? "(G)" : "   ", entryhi & ~ASID_MASK);
+		printk("PA0=0x%08x C0=%x %s%s%s\n", (entrylo0>>6)<<12, (entrylo0>>3) & 7, (entrylo0 & 4) ? "Dirty " : "", (entrylo0 & 2) ? "Valid " : "Invalid ", (entrylo0 & 1) ? "Global" : "");
+		printk("\t\t\t     PA1=0x%08x C1=%x %s%s%s\n", (entrylo1>>6)<<12, (entrylo1>>3) & 7, (entrylo1 & 4) ? "Dirty " : "", (entrylo1 & 2) ? "Valid " : "Invalid ", (entrylo1 & 1) ? "Global" : "");
+
+		dump_mm_page(entryhi & ~0xff);
+		dump_mm_page((entryhi & ~0xff) | 0x1000);
+		entry++;
+	}
+	BARRIER;
+	set_entryhi(old_ctx);
+
+	__restore_flags(flags);
+}
+
+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);
+        local_flush_tlb_all();
+        __restore_flags(flags);
+}
+
+/*
+ * Used for loading TLB entries before trap_init() has started, when we
+ * don't actually want to add a wired entry which remains throughout the
+ * lifetime of the system
+ */
+
+static int temp_tlb_entry __initdata;
+
+__init int add_temporary_entry(unsigned long entrylo0, unsigned long entrylo1,
+			       unsigned long entryhi, unsigned long pagemask)
+{
+	int ret = 0;
+	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();
+	if (--temp_tlb_entry < wired) {
+		printk(KERN_WARNING "No TLB space left for add_temporary_entry\n");
+		ret = -ENOSPC;
+		goto out;
+	}
+
+	set_index(temp_tlb_entry);
+	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);
+out:
+	__restore_flags(flags);
+	return ret;
+}
+
+static void __init probe_tlb(unsigned long config)
+{
+        unsigned long config1;
+
+        if (!(config & (1 << 31))) {
+	        /*
+		 * Not a MIPS64 complainant CPU.
+		 * Config 1 register not supported, we assume R4k style.
+		 */
+	        mips_cpu.tlbsize = 48;
+	} else {
+	        config1 = read_mips32_cp0_config1();
+		if (!((config >> 7) & 3))
+		        panic("No MMU present");
+		else
+		        mips_cpu.tlbsize = ((config1 >> 25) & 0x3f) + 1;
+	}
+
+	printk("Number of TLB entries %d.\n", mips_cpu.tlbsize);
+}
+
+void __init r4k_tlb_init(void)
+{
+	unsigned long config = read_32bit_cp0_register(CP0_CONFIG);
+
+	probe_tlb(config);
+	_update_mmu_cache = mips64_update_mmu_cache;
+	set_pagemask(PM_4K);
+	write_32bit_cp0_register(CP0_WIRED, 0);
+	temp_tlb_entry = mips_cpu.tlbsize - 1;
+	local_flush_tlb_all();
+
+	memcpy((void *)(KSEG0 + 0x80), &except_vec1_r4k, 0x80);
+	flush_icache_range(KSEG0, KSEG0 + 0x80);
+}