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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/mips/mm/tlb-r3k.c
parentInitial commit. (diff)
downloadlinux-upstream/4.19.249.tar.xz
linux-upstream/4.19.249.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--arch/mips/mm/tlb-r3k.c297
1 files changed, 297 insertions, 0 deletions
diff --git a/arch/mips/mm/tlb-r3k.c b/arch/mips/mm/tlb-r3k.c
new file mode 100644
index 000000000..6f589e011
--- /dev/null
+++ b/arch/mips/mm/tlb-r3k.c
@@ -0,0 +1,297 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * r2300.c: R2000 and R3000 specific mmu/cache code.
+ *
+ * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
+ *
+ * with a lot of changes to make this thing work for R3000s
+ * Tx39XX R4k style caches added. HK
+ * Copyright (C) 1998, 1999, 2000 Harald Koerfgen
+ * Copyright (C) 1998 Gleb Raiko & Vladimir Roganov
+ * Copyright (C) 2002 Ralf Baechle
+ * Copyright (C) 2002 Maciej W. Rozycki
+ */
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/mm.h>
+
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/mmu_context.h>
+#include <asm/tlbmisc.h>
+#include <asm/isadep.h>
+#include <asm/io.h>
+#include <asm/bootinfo.h>
+#include <asm/cpu.h>
+
+#undef DEBUG_TLB
+
+extern void build_tlb_refill_handler(void);
+
+/* CP0 hazard avoidance. */
+#define BARRIER \
+ __asm__ __volatile__( \
+ ".set push\n\t" \
+ ".set noreorder\n\t" \
+ "nop\n\t" \
+ ".set pop\n\t")
+
+int r3k_have_wired_reg; /* Should be in cpu_data? */
+
+/* TLB operations. */
+static void local_flush_tlb_from(int entry)
+{
+ unsigned long old_ctx;
+
+ old_ctx = read_c0_entryhi() & cpu_asid_mask(&current_cpu_data);
+ write_c0_entrylo0(0);
+ while (entry < current_cpu_data.tlbsize) {
+ write_c0_index(entry << 8);
+ write_c0_entryhi((entry | 0x80000) << 12);
+ entry++; /* BARRIER */
+ tlb_write_indexed();
+ }
+ write_c0_entryhi(old_ctx);
+}
+
+void local_flush_tlb_all(void)
+{
+ unsigned long flags;
+
+#ifdef DEBUG_TLB
+ printk("[tlball]");
+#endif
+ local_irq_save(flags);
+ local_flush_tlb_from(r3k_have_wired_reg ? read_c0_wired() : 8);
+ local_irq_restore(flags);
+}
+
+void local_flush_tlb_mm(struct mm_struct *mm)
+{
+ int cpu = smp_processor_id();
+
+ if (cpu_context(cpu, mm) != 0) {
+#ifdef DEBUG_TLB
+ printk("[tlbmm<%lu>]", (unsigned long)cpu_context(cpu, mm));
+#endif
+ drop_mmu_context(mm, cpu);
+ }
+}
+
+void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end)
+{
+ unsigned long asid_mask = cpu_asid_mask(&current_cpu_data);
+ struct mm_struct *mm = vma->vm_mm;
+ int cpu = smp_processor_id();
+
+ if (cpu_context(cpu, mm) != 0) {
+ unsigned long size, flags;
+
+#ifdef DEBUG_TLB
+ printk("[tlbrange<%lu,0x%08lx,0x%08lx>]",
+ cpu_context(cpu, mm) & asid_mask, start, end);
+#endif
+ local_irq_save(flags);
+ size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+ if (size <= current_cpu_data.tlbsize) {
+ int oldpid = read_c0_entryhi() & asid_mask;
+ int newpid = cpu_context(cpu, mm) & asid_mask;
+
+ start &= PAGE_MASK;
+ end += PAGE_SIZE - 1;
+ end &= PAGE_MASK;
+ while (start < end) {
+ int idx;
+
+ write_c0_entryhi(start | newpid);
+ start += PAGE_SIZE; /* BARRIER */
+ tlb_probe();
+ idx = read_c0_index();
+ write_c0_entrylo0(0);
+ write_c0_entryhi(KSEG0);
+ if (idx < 0) /* BARRIER */
+ continue;
+ tlb_write_indexed();
+ }
+ 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 size, flags;
+
+#ifdef DEBUG_TLB
+ printk("[tlbrange<%lu,0x%08lx,0x%08lx>]", start, end);
+#endif
+ local_irq_save(flags);
+ size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+ if (size <= current_cpu_data.tlbsize) {
+ int pid = read_c0_entryhi();
+
+ start &= PAGE_MASK;
+ end += PAGE_SIZE - 1;
+ end &= PAGE_MASK;
+
+ while (start < end) {
+ int idx;
+
+ write_c0_entryhi(start);
+ start += PAGE_SIZE; /* BARRIER */
+ tlb_probe();
+ idx = read_c0_index();
+ write_c0_entrylo0(0);
+ write_c0_entryhi(KSEG0);
+ if (idx < 0) /* BARRIER */
+ continue;
+ tlb_write_indexed();
+ }
+ 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)
+{
+ unsigned long asid_mask = cpu_asid_mask(&current_cpu_data);
+ int cpu = smp_processor_id();
+
+ if (cpu_context(cpu, vma->vm_mm) != 0) {
+ unsigned long flags;
+ int oldpid, newpid, idx;
+
+#ifdef DEBUG_TLB
+ printk("[tlbpage<%lu,0x%08lx>]", cpu_context(cpu, vma->vm_mm), page);
+#endif
+ newpid = cpu_context(cpu, vma->vm_mm) & asid_mask;
+ page &= PAGE_MASK;
+ local_irq_save(flags);
+ oldpid = read_c0_entryhi() & asid_mask;
+ write_c0_entryhi(page | newpid);
+ BARRIER;
+ tlb_probe();
+ idx = read_c0_index();
+ write_c0_entrylo0(0);
+ write_c0_entryhi(KSEG0);
+ if (idx < 0) /* BARRIER */
+ goto finish;
+ tlb_write_indexed();
+
+finish:
+ write_c0_entryhi(oldpid);
+ local_irq_restore(flags);
+ }
+}
+
+void __update_tlb(struct vm_area_struct *vma, unsigned long address, pte_t pte)
+{
+ unsigned long asid_mask = cpu_asid_mask(&current_cpu_data);
+ unsigned long flags;
+ int idx, pid;
+
+ /*
+ * Handle debugger faulting in for debugee.
+ */
+ if (current->active_mm != vma->vm_mm)
+ return;
+
+ pid = read_c0_entryhi() & asid_mask;
+
+#ifdef DEBUG_TLB
+ if ((pid != (cpu_context(cpu, vma->vm_mm) & asid_mask)) || (cpu_context(cpu, vma->vm_mm) == 0)) {
+ printk("update_mmu_cache: Wheee, bogus tlbpid mmpid=%lu tlbpid=%d\n",
+ (cpu_context(cpu, vma->vm_mm)), pid);
+ }
+#endif
+
+ local_irq_save(flags);
+ address &= PAGE_MASK;
+ write_c0_entryhi(address | pid);
+ BARRIER;
+ tlb_probe();
+ idx = read_c0_index();
+ write_c0_entrylo0(pte_val(pte));
+ write_c0_entryhi(address | pid);
+ if (idx < 0) { /* BARRIER */
+ tlb_write_random();
+ } else {
+ tlb_write_indexed();
+ }
+ write_c0_entryhi(pid);
+ local_irq_restore(flags);
+}
+
+void add_wired_entry(unsigned long entrylo0, unsigned long entrylo1,
+ unsigned long entryhi, unsigned long pagemask)
+{
+ unsigned long asid_mask = cpu_asid_mask(&current_cpu_data);
+ unsigned long flags;
+ unsigned long old_ctx;
+ static unsigned long wired = 0;
+
+ if (r3k_have_wired_reg) { /* TX39XX */
+ unsigned long old_pagemask;
+ unsigned long w;
+
+#ifdef DEBUG_TLB
+ printk("[tlbwired<entry lo0 %8x, hi %8x\n, pagemask %8x>]\n",
+ entrylo0, entryhi, pagemask);
+#endif
+
+ local_irq_save(flags);
+ /* Save old context and create impossible VPN2 value */
+ old_ctx = read_c0_entryhi() & asid_mask;
+ old_pagemask = read_c0_pagemask();
+ w = read_c0_wired();
+ write_c0_wired(w + 1);
+ write_c0_index(w << 8);
+ write_c0_pagemask(pagemask);
+ write_c0_entryhi(entryhi);
+ write_c0_entrylo0(entrylo0);
+ BARRIER;
+ tlb_write_indexed();
+
+ write_c0_entryhi(old_ctx);
+ write_c0_pagemask(old_pagemask);
+ local_flush_tlb_all();
+ local_irq_restore(flags);
+
+ } else if (wired < 8) {
+#ifdef DEBUG_TLB
+ printk("[tlbwired<entry lo0 %8x, hi %8x\n>]\n",
+ entrylo0, entryhi);
+#endif
+
+ local_irq_save(flags);
+ old_ctx = read_c0_entryhi() & asid_mask;
+ write_c0_entrylo0(entrylo0);
+ write_c0_entryhi(entryhi);
+ write_c0_index(wired);
+ wired++; /* BARRIER */
+ tlb_write_indexed();
+ write_c0_entryhi(old_ctx);
+ local_flush_tlb_all();
+ local_irq_restore(flags);
+ }
+}
+
+void tlb_init(void)
+{
+ switch (current_cpu_type()) {
+ case CPU_TX3922:
+ case CPU_TX3927:
+ r3k_have_wired_reg = 1;
+ write_c0_wired(0); /* Set to 8 on reset... */
+ break;
+ }
+ local_flush_tlb_from(0);
+ build_tlb_refill_handler();
+}