arch/sh/mm/tlb-sh3.c

   1 /*
   2  * arch/sh/mm/tlb-sh3.c
   3  *
   4  * SH-3 specific TLB operations
   5  *
   6  * Copyright (C) 1999  Niibe Yutaka
   7  * Copyright (C) 2002  Paul Mundt
   8  *
   9  * Released under the terms of the GNU GPL v2.0.
  10  */
  11 #include <linux/signal.h>
  12 #include <linux/sched.h>
  13 #include <linux/kernel.h>
  14 #include <linux/errno.h>
  15 #include <linux/string.h>
  16 #include <linux/types.h>
  17 #include <linux/ptrace.h>
  18 #include <linux/mman.h>
  19 #include <linux/mm.h>
  20 #include <linux/smp.h>
  21 #include <linux/interrupt.h>
  22
  23 #include <asm/io.h>
  24 #include <asm/uaccess.h>
  25 #include <asm/pgalloc.h>
  26 #include <asm/mmu_context.h>
  27 #include <asm/cacheflush.h>
  28
  29 void __update_tlb(struct vm_area_struct *vma, unsigned long address, pte_t pte)
  30 {
  31         unsigned long flags, pteval, vpn;
  32
  33         /*
  34          * Handle debugger faulting in for debugee.
  35          */
  36         if (vma && current->active_mm != vma->vm_mm)
  37                 return;
  38
  39         local_irq_save(flags);
  40
  41         /* Set PTEH register */
  42         vpn = (address & MMU_VPN_MASK) | get_asid();
  43         __raw_writel(vpn, MMU_PTEH);
  44
  45         pteval = pte_val(pte);
  46
  47         /* Set PTEL register */
  48         pteval &= _PAGE_FLAGS_HARDWARE_MASK; /* drop software flags */
  49         /* conveniently, we want all the software flags to be 0 anyway */
  50         __raw_writel(pteval, MMU_PTEL);
  51
  52         /* Load the TLB */
  53         asm volatile("ldtlb": /* no output */ : /* no input */ : "memory");
  54         local_irq_restore(flags);
  55 }
  56
  57 void local_flush_tlb_one(unsigned long asid, unsigned long page)
  58 {
  59         unsigned long addr, data;
  60         int i, ways = MMU_NTLB_WAYS;
  61
  62         /*
  63          * NOTE: PTEH.ASID should be set to this MM
  64          *       _AND_ we need to write ASID to the array.
  65          *
  66          * It would be simple if we didn't need to set PTEH.ASID...
  67          */
  68         addr = MMU_TLB_ADDRESS_ARRAY | (page & 0x1F000);
  69         data = (page & 0xfffe0000) | asid; /* VALID bit is off */
  70
  71         if ((current_cpu_data.flags & CPU_HAS_MMU_PAGE_ASSOC)) {
  72                 addr |= MMU_PAGE_ASSOC_BIT;
  73                 ways = 1;       /* we already know the way .. */
  74         }
  75
  76         for (i = 0; i < ways; i++)
  77                 __raw_writel(data, addr + (i << 8));
  78 }
  79
  80 void local_flush_tlb_all(void)
  81 {
  82         unsigned long flags, status;
  83
  84         /*
  85          * Flush all the TLB.
  86          *
  87          * Write to the MMU control register's bit:
  88          *      TF-bit for SH-3, TI-bit for SH-4.
  89          *      It's same position, bit #2.
  90          */
  91         local_irq_save(flags);
  92         status = __raw_readl(MMUCR);
  93         status |= 0x04;
  94         __raw_writel(status, MMUCR);
  95         ctrl_barrier();
  96         local_irq_restore(flags);
  97 }