patch-2.4.19 linux-2.4.19/arch/mips64/mm/tlb-sb1.c

• Lines: 307
• Date: Fri Aug 2 17:39:43 2002
• Orig file: linux-2.4.18/arch/mips64/mm/tlb-sb1.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.18/arch/mips64/mm/tlb-sb1.c linux-2.4.19/arch/mips64/mm/tlb-sb1.c
@@ -0,0 +1,306 @@
+/*
+ * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
+ * Copyright (C) 1997, 2001 Ralf Baechle (ralf@gnu.org)
+ * Copyright (C) 2000, 2001 Broadcom Corporation
+ *
+ * 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 <asm/mmu_context.h>
+#include <asm/bootinfo.h>
+#include <asm/cpu.h>
+
+/* Dump the current entry* and pagemask registers */
+static inline void dump_cur_tlb_regs(void)
+{
+	unsigned int entryhihi, entryhilo, entrylo0hi, entrylo0lo, entrylo1hi;
+	unsigned int entrylo1lo, pagemask;
+
+	__asm__ __volatile__ (
+		".set push             \n"
+		".set noreorder        \n"
+		"#.set mips64           \n"
+		".set mips4            \n"
+		".set noat             \n"
+		"     tlbr             \n"
+		"     dmfc0  $1, $10   \n"
+		"     dsrl32 %0, $1, 0 \n"
+		"     sra    %1, $1, 0 \n"
+		"     dmfc0  $1, $2    \n"
+		"     dsrl32 %2, $1, 0 \n"
+		"     sra    %3, $1, 0 \n"
+		"     dmfc0  $1, $3    \n"
+		"     dsrl32 %4, $1, 0 \n"
+		"     sra    %5, $1, 0 \n"
+		"     mfc0   %6, $5    \n"
+		".set pop              \n"
+		: "=r" (entryhihi),
+		"=r" (entryhilo),
+		"=r" (entrylo0hi),
+		"=r" (entrylo0lo),
+		"=r" (entrylo1hi),
+		"=r" (entrylo1lo),
+		"=r" (pagemask));
+	printk("%08X%08X %08X%08X %08X%08X %08X",
+	       entryhihi, entryhilo,
+	       entrylo0hi, entrylo0lo,
+	       entrylo1hi, entrylo1lo,
+	       pagemask);
+}
+
+void sb1_dump_tlb(void)
+{
+	int entry;
+	printk("Current TLB registers state:\n"
+	       "      EntryHi       EntryLo0          EntryLo1     PageMask  Index\n"
+	       "--------------------------------------------------------------------\n");
+	dump_cur_tlb_regs();
+	printk(" %08X\n", read_32bit_cp0_register(CP0_INDEX));
+	printk("\n\nFull TLB Dump:\n"
+	       "Idx      EntryHi       EntryLo0          EntryLo1     PageMask\n"
+	       "--------------------------------------------------------------\n");
+	for (entry = 0; entry < mips_cpu.tlbsize; entry++) {
+		set_index(entry);
+		printk("\n%02i ", entry);
+		__asm__ __volatile__ (
+			".set push             \n"
+			"#.set mips64           \n"
+			".set mips4           \n"
+			"     tlbr             \n"
+			".set pop              \n");
+		dump_cur_tlb_regs();
+	}
+	printk("\n");
+}
+
+void local_flush_tlb_all(void)
+{
+	unsigned long flags;
+	unsigned long old_ctx;
+	int entry;
+
+	__save_and_cli(flags);
+	/* Save old context and create impossible VPN2 value */
+	old_ctx = (get_entryhi() & 0xff);
+	set_entrylo0(0);
+	set_entrylo1(0);
+	for (entry = 0; entry < mips_cpu.tlbsize; entry++) {
+		set_entryhi(KSEG0 + (PAGE_SIZE << 1) * entry);
+		set_index(entry);
+		tlb_write_indexed();
+	}
+	set_entryhi(old_ctx);
+	__restore_flags(flags);	
+}
+
+
+/*
+ * Use a bogus region of memory (starting at 0) to sanitize the TLB's.  
+ * Use increments of the maximum page size (16MB), and check for duplicate
+ * entries before doing a given write.  Then, when we're safe from collisions
+ * with the firmware, go back and give all the entries invalid addresses with
+ * the normal flush routine.
+ */
+void sb1_sanitize_tlb(void)
+{
+	int entry;
+	long addr = 0;
+
+	long inc = 1<<24;  /* 16MB */
+	/* Save old context and create impossible VPN2 value */
+	set_entrylo0(0);
+	set_entrylo1(0);
+	for (entry = 0; entry < mips_cpu.tlbsize; entry++) {
+		do {
+			addr += inc;
+			set_entryhi(addr);
+			tlb_probe();
+		} while ((int)(get_index()) >= 0);
+		set_index(entry);
+		tlb_write_indexed();
+	}
+	/* Now that we know we're safe from collisions, we can safely flush
+	   the TLB with the "normal" routine. */
+	local_flush_tlb_all();
+}
+
+
+void local_flush_tlb_range(struct mm_struct *mm, unsigned long start,
+                      unsigned long end)
+{
+	unsigned long flags;
+	int cpu;
+
+	__save_and_cli(flags);
+	cpu = smp_processor_id();
+	if(CPU_CONTEXT(cpu, mm) != 0) {
+		int size;
+		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(cpu, 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);
+				tlb_probe();
+				idx = get_index();
+				set_entrylo0(0);
+				set_entrylo1(0);
+				set_entryhi(KSEG0 + (idx << (PAGE_SHIFT+1)));
+				if(idx < 0)
+					continue;
+				tlb_write_indexed();
+			}
+			set_entryhi(oldpid);
+		} else {
+			get_new_mmu_context(mm, cpu);
+			if (mm == current->active_mm)
+				set_entryhi(CPU_CONTEXT(cpu, mm) & 0xff);
+		}
+	}
+	__restore_flags(flags);
+}
+
+void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
+{
+	unsigned long flags;
+
+#ifdef CONFIG_SMP
+	/*
+	 * This variable is eliminated from CPU_CONTEXT() if SMP isn't defined,
+	 * so conditional it to get rid of silly "unused variable" compiler
+	 * complaints
+	 */
+	int cpu = smp_processor_id();
+#endif
+
+	__save_and_cli(flags);
+	if (CPU_CONTEXT(cpu, vma->vm_mm) != 0) {
+		int oldpid, newpid, idx;
+#ifdef DEBUG_TLB
+		printk("[tlbpage<%d,%08lx>]", CPU_CONTEXT(cpu, vma->vm_mm), page);
+#endif
+		newpid = (CPU_CONTEXT(cpu, vma->vm_mm) & 0xff);
+		page &= (PAGE_MASK << 1);
+		oldpid = (get_entryhi() & 0xff);
+		set_entryhi	(page | newpid);
+		tlb_probe();
+		idx = get_index();
+		set_entrylo0(0);
+		set_entrylo1(0);
+		if(idx < 0)
+			goto finish;
+		/* Make sure all entries differ. */  
+		set_entryhi(KSEG0+(idx<<(PAGE_SHIFT+1)));
+		tlb_write_indexed();
+	finish:
+		set_entryhi(oldpid);
+	}
+	__restore_flags(flags);
+}
+
+
+/* All entries common to a mm share an asid.  To effectively flush
+   these entries, we just bump the asid. */
+void local_flush_tlb_mm(struct mm_struct *mm)
+{
+	unsigned long flags;
+	int cpu;
+	__save_and_cli(flags);
+	cpu = smp_processor_id();
+	if (CPU_CONTEXT(cpu, mm) != 0) {
+		get_new_mmu_context(mm, smp_processor_id());
+		if (mm == current->active_mm) {
+			set_entryhi(CPU_CONTEXT(cpu, mm) & 0xff);
+		}
+	}
+	__restore_flags(flags);
+}
+
+/* Stolen from mips32 routines */
+
+void sb1_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;
+
+	__save_and_cli(flags);
+
+
+	pid = get_entryhi() & 0xff;
+
+#ifdef DEBUG_TLB
+	if((pid != (CPU_CONTEXT(cpu, vma->vm_mm) & 0xff)) || (CPU_CONTEXT(cpu, vma->vm_mm) == 0)) {
+		printk("update_mmu_cache: Wheee, bogus tlbpid mmpid=%d tlbpid=%d\n",
+		       (int) (CPU_CONTEXT(cpu, vma->vm_mm) & 0xff), pid);
+	}
+#endif
+
+	address &= (PAGE_MASK << 1);
+	set_entryhi(address | (pid));
+	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);
+	set_entryhi(address | (pid));
+	if (idx < 0) {
+		tlb_write_random();
+	} else {
+		tlb_write_indexed();
+	}
+	set_entryhi(pid);
+	__restore_flags(flags);
+}
+
+/*
+ * This is called from loadmmu.c.  We have to set up all the
+ * memory management function pointers, as well as initialize
+ * the caches and tlbs
+ */
+void sb1_tlb_init(void)
+{
+	u32 config1;
+
+	config1 = read_mips32_cp0_config1();
+	mips_cpu.tlbsize = ((config1 >> 25) & 0x3f) + 1;
+
+	/*
+	 * We don't know what state the firmware left the TLB's in, so this is
+	 * the ultra-conservative way to flush the TLB's and avoid machine
+	 * check exceptions due to duplicate TLB entries 
+	 */
+	sb1_sanitize_tlb();
+	_update_mmu_cache = sb1_update_mmu_cache;
+}