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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-r8k.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/mips/mm/tlb-r8k.c')
-rw-r--r--arch/mips/mm/tlb-r8k.c247
1 files changed, 247 insertions, 0 deletions
diff --git a/arch/mips/mm/tlb-r8k.c b/arch/mips/mm/tlb-r8k.c
new file mode 100644
index 000000000..e86e2e55a
--- /dev/null
+++ b/arch/mips/mm/tlb-r8k.c
@@ -0,0 +1,247 @@
+/*
+ * 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 (davem@davemloft.net)
+ * 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/sched.h>
+#include <linux/smp.h>
+#include <linux/mm.h>
+
+#include <asm/cpu.h>
+#include <asm/bootinfo.h>
+#include <asm/mmu_context.h>
+#include <asm/pgtable.h>
+
+extern void build_tlb_refill_handler(void);
+
+#define TFP_TLB_SIZE 384
+#define TFP_TLB_SET_SHIFT 7
+
+/* 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_entrylo(0);
+
+ for (entry = 0; entry < TFP_TLB_SIZE; entry++) {
+ write_c0_tlbset(entry >> TFP_TLB_SET_SHIFT);
+ write_c0_vaddr(entry << PAGE_SHIFT);
+ write_c0_entryhi(CKSEG0 + (entry << (PAGE_SHIFT + 1)));
+ mtc0_tlbw_hazard();
+ tlb_write();
+ }
+ 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();
+ unsigned long flags;
+ int oldpid, newpid, size;
+
+ if (!cpu_context(cpu, mm))
+ return;
+
+ size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+ size = (size + 1) >> 1;
+
+ local_irq_save(flags);
+
+ if (size > TFP_TLB_SIZE / 2) {
+ drop_mmu_context(mm, cpu);
+ goto out_restore;
+ }
+
+ oldpid = read_c0_entryhi();
+ newpid = cpu_asid(cpu, mm);
+
+ write_c0_entrylo(0);
+
+ start &= PAGE_MASK;
+ end += (PAGE_SIZE - 1);
+ end &= PAGE_MASK;
+ while (start < end) {
+ signed long idx;
+
+ write_c0_vaddr(start);
+ write_c0_entryhi(start);
+ start += PAGE_SIZE;
+ tlb_probe();
+ idx = read_c0_tlbset();
+ if (idx < 0)
+ continue;
+
+ write_c0_entryhi(CKSEG0 + (idx << (PAGE_SHIFT + 1)));
+ tlb_write();
+ }
+ write_c0_entryhi(oldpid);
+
+out_restore:
+ local_irq_restore(flags);
+}
+
+/* Usable for KV1 addresses only! */
+void local_flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+ unsigned long size, flags;
+
+ size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+ size = (size + 1) >> 1;
+
+ if (size > TFP_TLB_SIZE / 2) {
+ local_flush_tlb_all();
+ return;
+ }
+
+ local_irq_save(flags);
+
+ write_c0_entrylo(0);
+
+ start &= PAGE_MASK;
+ end += (PAGE_SIZE - 1);
+ end &= PAGE_MASK;
+ while (start < end) {
+ signed long idx;
+
+ write_c0_vaddr(start);
+ write_c0_entryhi(start);
+ start += PAGE_SIZE;
+ tlb_probe();
+ idx = read_c0_tlbset();
+ if (idx < 0)
+ continue;
+
+ write_c0_entryhi(CKSEG0 + (idx << (PAGE_SHIFT + 1)));
+ tlb_write();
+ }
+
+ local_irq_restore(flags);
+}
+
+void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
+{
+ int cpu = smp_processor_id();
+ unsigned long flags;
+ int oldpid, newpid;
+ signed long idx;
+
+ if (!cpu_context(cpu, vma->vm_mm))
+ return;
+
+ newpid = cpu_asid(cpu, vma->vm_mm);
+ page &= PAGE_MASK;
+ local_irq_save(flags);
+ oldpid = read_c0_entryhi();
+ write_c0_vaddr(page);
+ write_c0_entryhi(newpid);
+ tlb_probe();
+ idx = read_c0_tlbset();
+ if (idx < 0)
+ goto finish;
+
+ write_c0_entrylo(0);
+ write_c0_entryhi(CKSEG0 + (idx << (PAGE_SHIFT + 1)));
+ tlb_write();
+
+finish:
+ 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 pid;
+
+ /*
+ * Handle debugger faulting in for debugee.
+ */
+ if (current->active_mm != vma->vm_mm)
+ return;
+
+ pid = read_c0_entryhi() & cpu_asid_mask(&current_cpu_data);
+
+ local_irq_save(flags);
+ address &= PAGE_MASK;
+ write_c0_vaddr(address);
+ write_c0_entryhi(pid);
+ pgdp = pgd_offset(vma->vm_mm, address);
+ pmdp = pmd_offset(pgdp, address);
+ ptep = pte_offset_map(pmdp, address);
+ tlb_probe();
+
+ write_c0_entrylo(pte_val(*ptep++) >> 6);
+ tlb_write();
+
+ write_c0_entryhi(pid);
+ local_irq_restore(flags);
+}
+
+static void probe_tlb(unsigned long config)
+{
+ struct cpuinfo_mips *c = &current_cpu_data;
+
+ c->tlbsize = 3 * 128; /* 3 sets each 128 entries */
+}
+
+void tlb_init(void)
+{
+ unsigned int config = read_c0_config();
+ unsigned long status;
+
+ probe_tlb(config);
+
+ status = read_c0_status();
+ status &= ~(ST0_UPS | ST0_KPS);
+#ifdef CONFIG_PAGE_SIZE_4KB
+ status |= (TFP_PAGESIZE_4K << 32) | (TFP_PAGESIZE_4K << 36);
+#elif defined(CONFIG_PAGE_SIZE_8KB)
+ status |= (TFP_PAGESIZE_8K << 32) | (TFP_PAGESIZE_8K << 36);
+#elif defined(CONFIG_PAGE_SIZE_16KB)
+ status |= (TFP_PAGESIZE_16K << 32) | (TFP_PAGESIZE_16K << 36);
+#elif defined(CONFIG_PAGE_SIZE_64KB)
+ status |= (TFP_PAGESIZE_64K << 32) | (TFP_PAGESIZE_64K << 36);
+#endif
+ write_c0_status(status);
+
+ write_c0_wired(0);
+
+ local_flush_tlb_all();
+
+ build_tlb_refill_handler();
+}