Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c
new file mode 100644
index 0000000..59d38bc
--- /dev/null
+++ b/arch/mips/mm/tlb-r4k.c
@@ -0,0 +1,419 @@
+/*
+ * 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 (dm@engr.sgi.com)
+ * Copyright (C) 1997, 1998, 1999, 2000 Ralf Baechle ralf@gnu.org
+ * Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 2002 MIPS Technologies, Inc.  All rights reserved.
+ */
+#include <linux/config.h>
+#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>
+
+extern void build_tlb_refill_handler(void);
+
+/* 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;
+
+	local_irq_save(flags);
+	/* Save old context and create impossible VPN2 value */
+	old_ctx = read_c0_entryhi();
+	write_c0_entrylo0(0);
+	write_c0_entrylo1(0);
+
+	entry = read_c0_wired();
+
+	/* Blast 'em all away. */
+	while (entry < current_cpu_data.tlbsize) {
+		/*
+		 * Make sure all entries differ.  If they're not different
+		 * MIPS32 will take revenge ...
+		 */
+		write_c0_entryhi(CKSEG0 + (entry << (PAGE_SHIFT + 1)));
+		write_c0_index(entry);
+		mtc0_tlbw_hazard();
+		tlb_write_indexed();
+		entry++;
+	}
+	tlbw_use_hazard();
+	write_c0_entryhi(old_ctx);
+	local_irq_restore(flags);
+}
+
+void local_flush_tlb_mm(struct mm_struct *mm)
+{
+	int cpu = smp_processor_id();
+
+	if (cpu_context(cpu, mm) != 0)
+		drop_mmu_context(mm,cpu);
+}
+
+void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+	unsigned long end)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	int cpu = smp_processor_id();
+
+	if (cpu_context(cpu, mm) != 0) {
+		unsigned long flags;
+		int size;
+
+		local_irq_save(flags);
+		size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+		size = (size + 1) >> 1;
+		if (size <= current_cpu_data.tlbsize/2) {
+			int oldpid = read_c0_entryhi();
+			int newpid = cpu_asid(cpu, mm);
+
+			start &= (PAGE_MASK << 1);
+			end += ((PAGE_SIZE << 1) - 1);
+			end &= (PAGE_MASK << 1);
+			while (start < end) {
+				int idx;
+
+				write_c0_entryhi(start | newpid);
+				start += (PAGE_SIZE << 1);
+				mtc0_tlbw_hazard();
+				tlb_probe();
+				BARRIER;
+				idx = read_c0_index();
+				write_c0_entrylo0(0);
+				write_c0_entrylo1(0);
+				if (idx < 0)
+					continue;
+				/* Make sure all entries differ. */
+				write_c0_entryhi(CKSEG0 +
+				                 (idx << (PAGE_SHIFT + 1)));
+				mtc0_tlbw_hazard();
+				tlb_write_indexed();
+			}
+			tlbw_use_hazard();
+			write_c0_entryhi(oldpid);
+		} else {
+			drop_mmu_context(mm, cpu);
+		}
+		local_irq_restore(flags);
+	}
+}
+
+void local_flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+	unsigned long flags;
+	int size;
+
+	local_irq_save(flags);
+	size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+	size = (size + 1) >> 1;
+	if (size <= current_cpu_data.tlbsize / 2) {
+		int pid = read_c0_entryhi();
+
+		start &= (PAGE_MASK << 1);
+		end += ((PAGE_SIZE << 1) - 1);
+		end &= (PAGE_MASK << 1);
+
+		while (start < end) {
+			int idx;
+
+			write_c0_entryhi(start);
+			start += (PAGE_SIZE << 1);
+			mtc0_tlbw_hazard();
+			tlb_probe();
+			BARRIER;
+			idx = read_c0_index();
+			write_c0_entrylo0(0);
+			write_c0_entrylo1(0);
+			if (idx < 0)
+				continue;
+			/* Make sure all entries differ. */
+			write_c0_entryhi(CKSEG0 + (idx << (PAGE_SHIFT + 1)));
+			mtc0_tlbw_hazard();
+			tlb_write_indexed();
+		}
+		tlbw_use_hazard();
+		write_c0_entryhi(pid);
+	} else {
+		local_flush_tlb_all();
+	}
+	local_irq_restore(flags);
+}
+
+void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
+{
+	int cpu = smp_processor_id();
+
+	if (cpu_context(cpu, vma->vm_mm) != 0) {
+		unsigned long flags;
+		int oldpid, newpid, idx;
+
+		newpid = cpu_asid(cpu, vma->vm_mm);
+		page &= (PAGE_MASK << 1);
+		local_irq_save(flags);
+		oldpid = read_c0_entryhi();
+		write_c0_entryhi(page | newpid);
+		mtc0_tlbw_hazard();
+		tlb_probe();
+		BARRIER;
+		idx = read_c0_index();
+		write_c0_entrylo0(0);
+		write_c0_entrylo1(0);
+		if (idx < 0)
+			goto finish;
+		/* Make sure all entries differ. */
+		write_c0_entryhi(CKSEG0 + (idx << (PAGE_SHIFT + 1)));
+		mtc0_tlbw_hazard();
+		tlb_write_indexed();
+		tlbw_use_hazard();
+
+	finish:
+		write_c0_entryhi(oldpid);
+		local_irq_restore(flags);
+	}
+}
+
+/*
+ * This one is only used for pages with the global bit set so we don't care
+ * much about the ASID.
+ */
+void local_flush_tlb_one(unsigned long page)
+{
+	unsigned long flags;
+	int oldpid, idx;
+
+	local_irq_save(flags);
+	page &= (PAGE_MASK << 1);
+	oldpid = read_c0_entryhi();
+	write_c0_entryhi(page);
+	mtc0_tlbw_hazard();
+	tlb_probe();
+	BARRIER;
+	idx = read_c0_index();
+	write_c0_entrylo0(0);
+	write_c0_entrylo1(0);
+	if (idx >= 0) {
+		/* Make sure all entries differ. */
+		write_c0_entryhi(CKSEG0 + (idx << (PAGE_SHIFT + 1)));
+		mtc0_tlbw_hazard();
+		tlb_write_indexed();
+		tlbw_use_hazard();
+	}
+	write_c0_entryhi(oldpid);
+
+	local_irq_restore(flags);
+}
+
+/*
+ * 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_tlb(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 = read_c0_entryhi() & ASID_MASK;
+
+	local_irq_save(flags);
+	address &= (PAGE_MASK << 1);
+	write_c0_entryhi(address | pid);
+	pgdp = pgd_offset(vma->vm_mm, address);
+	mtc0_tlbw_hazard();
+	tlb_probe();
+	BARRIER;
+	pmdp = pmd_offset(pgdp, address);
+	idx = read_c0_index();
+	ptep = pte_offset_map(pmdp, address);
+
+ #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
+ 	write_c0_entrylo0(ptep->pte_high);
+ 	ptep++;
+ 	write_c0_entrylo1(ptep->pte_high);
+#else
+  	write_c0_entrylo0(pte_val(*ptep++) >> 6);
+  	write_c0_entrylo1(pte_val(*ptep) >> 6);
+#endif
+	write_c0_entryhi(address | pid);
+	mtc0_tlbw_hazard();
+	if (idx < 0)
+		tlb_write_random();
+	else
+		tlb_write_indexed();
+	tlbw_use_hazard();
+	write_c0_entryhi(pid);
+	local_irq_restore(flags);
+}
+
+#if 0
+static void r4k_update_mmu_cache_hwbug(struct vm_area_struct * vma,
+				       unsigned long address, pte_t pte)
+{
+	unsigned long flags;
+	unsigned int asid;
+	pgd_t *pgdp;
+	pmd_t *pmdp;
+	pte_t *ptep;
+	int idx;
+
+	local_irq_save(flags);
+	address &= (PAGE_MASK << 1);
+	asid = read_c0_entryhi() & ASID_MASK;
+	write_c0_entryhi(address | asid);
+	pgdp = pgd_offset(vma->vm_mm, address);
+	mtc0_tlbw_hazard();
+	tlb_probe();
+	BARRIER;
+	pmdp = pmd_offset(pgdp, address);
+	idx = read_c0_index();
+	ptep = pte_offset_map(pmdp, address);
+	write_c0_entrylo0(pte_val(*ptep++) >> 6);
+	write_c0_entrylo1(pte_val(*ptep) >> 6);
+	mtc0_tlbw_hazard();
+	if (idx < 0)
+		tlb_write_random();
+	else
+		tlb_write_indexed();
+	tlbw_use_hazard();
+	local_irq_restore(flags);
+}
+#endif
+
+void __init 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;
+
+	local_irq_save(flags);
+	/* Save old context and create impossible VPN2 value */
+	old_ctx = read_c0_entryhi();
+	old_pagemask = read_c0_pagemask();
+	wired = read_c0_wired();
+	write_c0_wired(wired + 1);
+	write_c0_index(wired);
+	BARRIER;
+	write_c0_pagemask(pagemask);
+	write_c0_entryhi(entryhi);
+	write_c0_entrylo0(entrylo0);
+	write_c0_entrylo1(entrylo1);
+	mtc0_tlbw_hazard();
+	tlb_write_indexed();
+	tlbw_use_hazard();
+
+	write_c0_entryhi(old_ctx);
+	BARRIER;
+	write_c0_pagemask(old_pagemask);
+	local_flush_tlb_all();
+	local_irq_restore(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;
+
+	local_irq_save(flags);
+	/* Save old context and create impossible VPN2 value */
+	old_ctx = read_c0_entryhi();
+	old_pagemask = read_c0_pagemask();
+	wired = read_c0_wired();
+	if (--temp_tlb_entry < wired) {
+		printk(KERN_WARNING "No TLB space left for add_temporary_entry\n");
+		ret = -ENOSPC;
+		goto out;
+	}
+
+	write_c0_index(temp_tlb_entry);
+	write_c0_pagemask(pagemask);
+	write_c0_entryhi(entryhi);
+	write_c0_entrylo0(entrylo0);
+	write_c0_entrylo1(entrylo1);
+	mtc0_tlbw_hazard();
+	tlb_write_indexed();
+	tlbw_use_hazard();
+
+	write_c0_entryhi(old_ctx);
+	write_c0_pagemask(old_pagemask);
+out:
+	local_irq_restore(flags);
+	return ret;
+}
+
+static void __init probe_tlb(unsigned long config)
+{
+	struct cpuinfo_mips *c = &current_cpu_data;
+	unsigned int reg;
+
+	/*
+	 * If this isn't a MIPS32 / MIPS64 compliant CPU.  Config 1 register
+	 * is not supported, we assume R4k style.  Cpu probing already figured
+	 * out the number of tlb entries.
+	 */
+	if ((c->processor_id  & 0xff0000) == PRID_COMP_LEGACY)
+		return;
+
+	reg = read_c0_config1();
+	if (!((config >> 7) & 3))
+		panic("No TLB present");
+
+	c->tlbsize = ((reg >> 25) & 0x3f) + 1;
+}
+
+void __init tlb_init(void)
+{
+	unsigned int config = read_c0_config();
+
+	/*
+	 * 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.
+	 */
+	probe_tlb(config);
+	write_c0_pagemask(PM_DEFAULT_MASK);
+	write_c0_wired(0);
+	temp_tlb_entry = current_cpu_data.tlbsize - 1;
+	local_flush_tlb_all();
+
+	build_tlb_refill_handler();
+}