xref: /openbmc/linux/arch/csky/abiv2/cacheflush.c (revision 842ed298)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
3 
4 #include <linux/cache.h>
5 #include <linux/highmem.h>
6 #include <linux/mm.h>
7 #include <asm/cache.h>
8 
9 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
10 		      pte_t *pte)
11 {
12 	unsigned long addr;
13 	struct page *page;
14 
15 	page = pfn_to_page(pte_pfn(*pte));
16 	if (page == ZERO_PAGE(0))
17 		return;
18 
19 	if (test_and_set_bit(PG_dcache_clean, &page->flags))
20 		return;
21 
22 	addr = (unsigned long) kmap_atomic(page);
23 
24 	dcache_wb_range(addr, addr + PAGE_SIZE);
25 
26 	if (vma->vm_flags & VM_EXEC)
27 		icache_inv_range(addr, addr + PAGE_SIZE);
28 
29 	kunmap_atomic((void *) addr);
30 }
31 
32 void flush_icache_deferred(struct mm_struct *mm)
33 {
34 	unsigned int cpu = smp_processor_id();
35 	cpumask_t *mask = &mm->context.icache_stale_mask;
36 
37 	if (cpumask_test_cpu(cpu, mask)) {
38 		cpumask_clear_cpu(cpu, mask);
39 		/*
40 		 * Ensure the remote hart's writes are visible to this hart.
41 		 * This pairs with a barrier in flush_icache_mm.
42 		 */
43 		smp_mb();
44 		local_icache_inv_all(NULL);
45 	}
46 }
47 
48 void flush_icache_mm_range(struct mm_struct *mm,
49 		unsigned long start, unsigned long end)
50 {
51 	unsigned int cpu;
52 	cpumask_t others, *mask;
53 
54 	preempt_disable();
55 
56 #ifdef CONFIG_CPU_HAS_ICACHE_INS
57 	if (mm == current->mm) {
58 		icache_inv_range(start, end);
59 		preempt_enable();
60 		return;
61 	}
62 #endif
63 
64 	/* Mark every hart's icache as needing a flush for this MM. */
65 	mask = &mm->context.icache_stale_mask;
66 	cpumask_setall(mask);
67 
68 	/* Flush this hart's I$ now, and mark it as flushed. */
69 	cpu = smp_processor_id();
70 	cpumask_clear_cpu(cpu, mask);
71 	local_icache_inv_all(NULL);
72 
73 	/*
74 	 * Flush the I$ of other harts concurrently executing, and mark them as
75 	 * flushed.
76 	 */
77 	cpumask_andnot(&others, mm_cpumask(mm), cpumask_of(cpu));
78 
79 	if (mm != current->active_mm || !cpumask_empty(&others)) {
80 		on_each_cpu_mask(&others, local_icache_inv_all, NULL, 1);
81 		cpumask_clear(mask);
82 	}
83 
84 	preempt_enable();
85 }
86