xref: /openbmc/linux/arch/sh/mm/tlb-sh4.c (revision a09d2831)
1 /*
2  * arch/sh/mm/tlb-sh4.c
3  *
4  * SH-4 specific TLB operations
5  *
6  * Copyright (C) 1999  Niibe Yutaka
7  * Copyright (C) 2002 - 2007 Paul Mundt
8  *
9  * Released under the terms of the GNU GPL v2.0.
10  */
11 #include <linux/kernel.h>
12 #include <linux/mm.h>
13 #include <linux/io.h>
14 #include <asm/system.h>
15 #include <asm/mmu_context.h>
16 #include <asm/cacheflush.h>
17 
18 void __update_tlb(struct vm_area_struct *vma, unsigned long address, pte_t pte)
19 {
20 	unsigned long flags, pteval, vpn;
21 
22 	/*
23 	 * Handle debugger faulting in for debugee.
24 	 */
25 	if (vma && current->active_mm != vma->vm_mm)
26 		return;
27 
28 	local_irq_save(flags);
29 
30 	/* Set PTEH register */
31 	vpn = (address & MMU_VPN_MASK) | get_asid();
32 	ctrl_outl(vpn, MMU_PTEH);
33 
34 	pteval = pte.pte_low;
35 
36 	/* Set PTEA register */
37 #ifdef CONFIG_X2TLB
38 	/*
39 	 * For the extended mode TLB this is trivial, only the ESZ and
40 	 * EPR bits need to be written out to PTEA, with the remainder of
41 	 * the protection bits (with the exception of the compat-mode SZ
42 	 * and PR bits, which are cleared) being written out in PTEL.
43 	 */
44 	ctrl_outl(pte.pte_high, MMU_PTEA);
45 #else
46 	if (cpu_data->flags & CPU_HAS_PTEA) {
47 		/* The last 3 bits and the first one of pteval contains
48 		 * the PTEA timing control and space attribute bits
49 		 */
50 		ctrl_outl(copy_ptea_attributes(pteval), MMU_PTEA);
51 	}
52 #endif
53 
54 	/* Set PTEL register */
55 	pteval &= _PAGE_FLAGS_HARDWARE_MASK; /* drop software flags */
56 #ifdef CONFIG_CACHE_WRITETHROUGH
57 	pteval |= _PAGE_WT;
58 #endif
59 	/* conveniently, we want all the software flags to be 0 anyway */
60 	ctrl_outl(pteval, MMU_PTEL);
61 
62 	/* Load the TLB */
63 	asm volatile("ldtlb": /* no output */ : /* no input */ : "memory");
64 	local_irq_restore(flags);
65 }
66 
67 void __uses_jump_to_uncached local_flush_tlb_one(unsigned long asid,
68 						 unsigned long page)
69 {
70 	unsigned long addr, data;
71 
72 	/*
73 	 * NOTE: PTEH.ASID should be set to this MM
74 	 *       _AND_ we need to write ASID to the array.
75 	 *
76 	 * It would be simple if we didn't need to set PTEH.ASID...
77 	 */
78 	addr = MMU_UTLB_ADDRESS_ARRAY | MMU_PAGE_ASSOC_BIT;
79 	data = page | asid; /* VALID bit is off */
80 	jump_to_uncached();
81 	ctrl_outl(data, addr);
82 	back_to_cached();
83 }
84