kernel/arch/csky/mm/cachev1.c

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

#include <linux/spinlock.h>
#include <asm/cache.h>
#include <abi/reg_ops.h>

/* for L1-cache */
#define INS_CACHE		(1 << 0)
#define DATA_CACHE		(1 << 1)
#define CACHE_INV		(1 << 4)
#define CACHE_CLR		(1 << 5)
#define CACHE_OMS		(1 << 6)
#define CACHE_ITS		(1 << 7)
#define CACHE_LICF		(1 << 31)

/* for L2-cache */
#define CR22_LEVEL_SHIFT	(1)
#define CR22_SET_SHIFT		(7)
#define CR22_WAY_SHIFT		(30)
#define CR22_WAY_SHIFT_L2	(29)

static DEFINE_SPINLOCK(cache_lock);

static inline void cache_op_line(unsigned long i, unsigned int val)
{
	mtcr("cr22", i);
	mtcr("cr17", val);
}

#define CCR2_L2E (1 << 3)
static void cache_op_all(unsigned int value, unsigned int l2)
{
	mtcr("cr17", value | CACHE_CLR);
	mb();

	if (l2 && (mfcr_ccr2() & CCR2_L2E)) {
		mtcr("cr24", value | CACHE_CLR);
		mb();
	}
}

static void cache_op_range(
	unsigned int start,
	unsigned int end,
	unsigned int value,
	unsigned int l2)
{
	unsigned long i, flags;
	unsigned int val = value | CACHE_CLR | CACHE_OMS;
	bool l2_sync;

	if (unlikely((end - start) >= PAGE_SIZE) ||
	    unlikely(start < PAGE_OFFSET) ||
	    unlikely(start >= PAGE_OFFSET + LOWMEM_LIMIT)) {
		cache_op_all(value, l2);
		return;
	}

	if ((mfcr_ccr2() & CCR2_L2E) && l2)
		l2_sync = 1;
	else
		l2_sync = 0;

	spin_lock_irqsave(&cache_lock, flags);

	i = start & ~(L1_CACHE_BYTES - 1);
	for (; i < end; i += L1_CACHE_BYTES) {
		cache_op_line(i, val);
		if (l2_sync) {
			mb();
			mtcr("cr24", val);
		}
	}
	spin_unlock_irqrestore(&cache_lock, flags);

	mb();
}

void dcache_wb_line(unsigned long start)
{
	asm volatile("idly4\n":::"memory");
	cache_op_line(start, DATA_CACHE|CACHE_CLR);
	mb();
}

void icache_inv_range(unsigned long start, unsigned long end)
{
	cache_op_range(start, end, INS_CACHE|CACHE_INV, 0);
}

void icache_inv_all(void)
{
	cache_op_all(INS_CACHE|CACHE_INV, 0);
}

void local_icache_inv_all(void *priv)
{
	cache_op_all(INS_CACHE|CACHE_INV, 0);
}

void dcache_wb_range(unsigned long start, unsigned long end)
{
	cache_op_range(start, end, DATA_CACHE|CACHE_CLR, 0);
}

void dcache_wbinv_all(void)
{
	cache_op_all(DATA_CACHE|CACHE_CLR|CACHE_INV, 0);
}

void cache_wbinv_range(unsigned long start, unsigned long end)
{
	cache_op_range(start, end, INS_CACHE|DATA_CACHE|CACHE_CLR|CACHE_INV, 0);
}
EXPORT_SYMBOL(cache_wbinv_range);

void cache_wbinv_all(void)
{
	cache_op_all(INS_CACHE|DATA_CACHE|CACHE_CLR|CACHE_INV, 0);
}

void dma_wbinv_range(unsigned long start, unsigned long end)
{
	cache_op_range(start, end, DATA_CACHE|CACHE_CLR|CACHE_INV, 1);
}

void dma_inv_range(unsigned long start, unsigned long end)
{
	cache_op_range(start, end, DATA_CACHE|CACHE_CLR|CACHE_INV, 1);
}

void dma_wb_range(unsigned long start, unsigned long end)
{
	cache_op_range(start, end, DATA_CACHE|CACHE_CLR|CACHE_INV, 1);
}