xref: /openbmc/linux/arch/sh/mm/tlb-sh3.c (revision 4f6cce39)
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 <linux/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 }
98