xref: /openbmc/linux/arch/sh/mm/tlb-sh3.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * arch/sh/mm/tlb-sh3.c
4  *
5  * SH-3 specific TLB operations
6  *
7  * Copyright (C) 1999  Niibe Yutaka
8  * Copyright (C) 2002  Paul Mundt
9  */
10 #include <linux/signal.h>
11 #include <linux/sched.h>
12 #include <linux/kernel.h>
13 #include <linux/errno.h>
14 #include <linux/string.h>
15 #include <linux/types.h>
16 #include <linux/ptrace.h>
17 #include <linux/mman.h>
18 #include <linux/mm.h>
19 #include <linux/smp.h>
20 #include <linux/interrupt.h>
21 
22 #include <asm/io.h>
23 #include <linux/uaccess.h>
24 #include <asm/mmu_context.h>
25 #include <asm/cacheflush.h>
26 
27 void __update_tlb(struct vm_area_struct *vma, unsigned long address, pte_t pte)
28 {
29 	unsigned long flags, pteval, vpn;
30 
31 	/*
32 	 * Handle debugger faulting in for debugee.
33 	 */
34 	if (vma && current->active_mm != vma->vm_mm)
35 		return;
36 
37 	local_irq_save(flags);
38 
39 	/* Set PTEH register */
40 	vpn = (address & MMU_VPN_MASK) | get_asid();
41 	__raw_writel(vpn, MMU_PTEH);
42 
43 	pteval = pte_val(pte);
44 
45 	/* Set PTEL register */
46 	pteval &= _PAGE_FLAGS_HARDWARE_MASK; /* drop software flags */
47 	/* conveniently, we want all the software flags to be 0 anyway */
48 	__raw_writel(pteval, MMU_PTEL);
49 
50 	/* Load the TLB */
51 	asm volatile("ldtlb": /* no output */ : /* no input */ : "memory");
52 	local_irq_restore(flags);
53 }
54 
55 void local_flush_tlb_one(unsigned long asid, unsigned long page)
56 {
57 	unsigned long addr, data;
58 	int i, ways = MMU_NTLB_WAYS;
59 
60 	/*
61 	 * NOTE: PTEH.ASID should be set to this MM
62 	 *       _AND_ we need to write ASID to the array.
63 	 *
64 	 * It would be simple if we didn't need to set PTEH.ASID...
65 	 */
66 	addr = MMU_TLB_ADDRESS_ARRAY | (page & 0x1F000);
67 	data = (page & 0xfffe0000) | asid; /* VALID bit is off */
68 
69 	if ((current_cpu_data.flags & CPU_HAS_MMU_PAGE_ASSOC)) {
70 		addr |= MMU_PAGE_ASSOC_BIT;
71 		ways = 1;	/* we already know the way .. */
72 	}
73 
74 	for (i = 0; i < ways; i++)
75 		__raw_writel(data, addr + (i << 8));
76 }
77 
78 void local_flush_tlb_all(void)
79 {
80 	unsigned long flags, status;
81 
82 	/*
83 	 * Flush all the TLB.
84 	 *
85 	 * Write to the MMU control register's bit:
86 	 *	TF-bit for SH-3, TI-bit for SH-4.
87 	 *      It's same position, bit #2.
88 	 */
89 	local_irq_save(flags);
90 	status = __raw_readl(MMUCR);
91 	status |= 0x04;
92 	__raw_writel(status, MMUCR);
93 	ctrl_barrier();
94 	local_irq_restore(flags);
95 }
96