// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.

#include <linux/cache.h>
#include <linux/highmem.h>
#include <linux/mm.h>
#include <asm/cache.h>

void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
		      pte_t *pte)
{
	unsigned long addr;
	struct page *page;

	if (!pfn_valid(pte_pfn(*pte)))
		return;

	page = pfn_to_page(pte_pfn(*pte));
	if (page == ZERO_PAGE(0))
		return;

	if (test_and_set_bit(PG_dcache_clean, &page->flags))
		return;

	addr = (unsigned long) kmap_atomic(page);

	dcache_wb_range(addr, addr + PAGE_SIZE);

	if (vma->vm_flags & VM_EXEC)
		icache_inv_range(addr, addr + PAGE_SIZE);

	kunmap_atomic((void *) addr);
}

void flush_icache_deferred(struct mm_struct *mm)
{
	unsigned int cpu = smp_processor_id();
	cpumask_t *mask = &mm->context.icache_stale_mask;

	if (cpumask_test_cpu(cpu, mask)) {
		cpumask_clear_cpu(cpu, mask);
		/*
		 * Ensure the remote hart's writes are visible to this hart.
		 * This pairs with a barrier in flush_icache_mm.
		 */
		smp_mb();
		local_icache_inv_all(NULL);
	}
}

void flush_icache_mm_range(struct mm_struct *mm,
		unsigned long start, unsigned long end)
{
	unsigned int cpu;
	cpumask_t others, *mask;

	preempt_disable();

#ifdef CONFIG_CPU_HAS_ICACHE_INS
	if (mm == current->mm) {
		icache_inv_range(start, end);
		preempt_enable();
		return;
	}
#endif

	/* Mark every hart's icache as needing a flush for this MM. */
	mask = &mm->context.icache_stale_mask;
	cpumask_setall(mask);

	/* Flush this hart's I$ now, and mark it as flushed. */
	cpu = smp_processor_id();
	cpumask_clear_cpu(cpu, mask);
	local_icache_inv_all(NULL);

	/*
	 * Flush the I$ of other harts concurrently executing, and mark them as
	 * flushed.
	 */
	cpumask_andnot(&others, mm_cpumask(mm), cpumask_of(cpu));

	if (mm != current->active_mm || !cpumask_empty(&others)) {
		on_each_cpu_mask(&others, local_icache_inv_all, NULL, 1);
		cpumask_clear(mask);
	}

	preempt_enable();
}