zephyr/arch/arc/core/cache.c

175 lines
4.3 KiB
C

/* cache.c - d-cache support for ARC CPUs */
/*
* Copyright (c) 2016 Synopsys, Inc. All rights reserved.
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* @brief d-cache manipulation
*
* This module contains functions for manipulation of the d-cache.
*/
#include <kernel.h>
#include <arch/cpu.h>
#include <misc/util.h>
#include <toolchain.h>
#include <cache.h>
#include <linker/linker-defs.h>
#include <arch/arc/v2/aux_regs.h>
#include <kernel_internal.h>
#include <misc/__assert.h>
#include <init.h>
#if defined(CONFIG_CACHE_FLUSHING)
#if (CONFIG_CACHE_LINE_SIZE == 0) && !defined(CONFIG_CACHE_LINE_SIZE_DETECT)
#error Cannot use this implementation with a cache line size of 0
#endif
#if defined(CONFIG_CACHE_LINE_SIZE_DETECT)
#define DCACHE_LINE_SIZE sys_cache_line_size
#else
#define DCACHE_LINE_SIZE CONFIG_CACHE_LINE_SIZE
#endif
#define DC_CTRL_DC_ENABLE 0x0 /* enable d-cache */
#define DC_CTRL_DC_DISABLE 0x1 /* disable d-cache */
#define DC_CTRL_INVALID_ONLY 0x0 /* invalid d-cache only */
#define DC_CTRL_INVALID_FLUSH 0x40 /* invalid and flush d-cache */
#define DC_CTRL_ENABLE_FLUSH_LOCKED 0x80 /* locked d-cache can be flushed */
#define DC_CTRL_DISABLE_FLUSH_LOCKED 0x0 /* locked d-cache cannot be flushed */
#define DC_CTRL_FLUSH_STATUS 0x100/* flush status */
#define DC_CTRL_DIRECT_ACCESS 0x0 /* direct access mode */
#define DC_CTRL_INDIRECT_ACCESS 0x20 /* indirect access mode */
#define DC_CTRL_OP_SUCCEEDED 0x4 /* d-cache operation succeeded */
static int dcache_available(void)
{
unsigned long val = _arc_v2_aux_reg_read(_ARC_V2_D_CACHE_BUILD);
val &= 0xff; /* extract version */
return (val == 0)?0:1;
}
static void dcache_dc_ctrl(u32_t dcache_en_mask)
{
if (!dcache_available())
return;
_arc_v2_aux_reg_write(_ARC_V2_DC_CTRL, dcache_en_mask);
}
static void dcache_enable(void)
{
dcache_dc_ctrl(DC_CTRL_DC_ENABLE);
}
/**
*
* @brief Flush multiple d-cache lines to memory
*
* No alignment is required for either <start_addr> or <size>, but since
* dcache_flush_mlines() iterates on the d-cache lines, a cache line
* alignment for both is optimal.
*
* The d-cache line size is specified either via the CONFIG_CACHE_LINE_SIZE
* kconfig option or it is detected at runtime.
*
* @param start_addr the pointer to start the multi-line flush
* @param size the number of bytes that are to be flushed
*
* @return N/A
*/
static void dcache_flush_mlines(u32_t start_addr, u32_t size)
{
u32_t end_addr;
unsigned int key;
if (!dcache_available() || (size == 0)) {
return;
}
end_addr = start_addr + size - 1;
start_addr &= (u32_t)(~(DCACHE_LINE_SIZE - 1));
key = irq_lock(); /* --enter critical section-- */
do {
_arc_v2_aux_reg_write(_ARC_V2_DC_FLDL, start_addr);
__asm__ volatile("nop_s");
__asm__ volatile("nop_s");
__asm__ volatile("nop_s");
/* wait for flush completion */
do {
if ((_arc_v2_aux_reg_read(_ARC_V2_DC_CTRL) &
DC_CTRL_FLUSH_STATUS) == 0)
break;
} while (1);
start_addr += DCACHE_LINE_SIZE;
} while (start_addr <= end_addr);
irq_unlock(key); /* --exit critical section-- */
}
/**
*
* @brief Flush d-cache lines to main memory
*
* No alignment is required for either <virt> or <size>, but since
* sys_cache_flush() iterates on the d-cache lines, a d-cache line alignment for
* both is optimal.
*
* The d-cache line size is specified either via the CONFIG_CACHE_LINE_SIZE
* kconfig option or it is detected at runtime.
*
* @param start_addr the pointer to start the multi-line flush
* @param size the number of bytes that are to be flushed
*
* @return N/A
*/
void sys_cache_flush(vaddr_t start_addr, size_t size)
{
dcache_flush_mlines((u32_t)start_addr, (u32_t)size);
}
#if defined(CONFIG_CACHE_LINE_SIZE_DETECT)
size_t sys_cache_line_size;
static void init_dcache_line_size(void)
{
u32_t val;
val = _arc_v2_aux_reg_read(_ARC_V2_D_CACHE_BUILD);
__ASSERT((val&0xff) != 0, "d-cache is not present");
val = ((val>>16) & 0xf) + 1;
val *= 16;
sys_cache_line_size = (size_t) val;
}
#endif
static int init_dcache(struct device *unused)
{
ARG_UNUSED(unused);
dcache_enable();
#if defined(CONFIG_CACHE_LINE_SIZE_DETECT)
init_dcache_line_size();
#endif
return 0;
}
SYS_INIT(init_dcache, PRE_KERNEL_1, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);
#endif /* CONFIG_CACHE_FLUSHING */