SmartAudio/lichee/linux-4.9/arch/arm/mach-sunxi/sun8i-cci.c

200 lines
3.8 KiB
C

/*
* linux/arch/arm/mach-sunxi/sun9i-cci.c
*
* Copyright(c) 2013-2015 Allwinnertech Co., Ltd.
* http://www.allwinnertech.com
*
* Author: sunny <sunny@allwinnertech.com>
*
* allwinner sun9i soc platform CCI(Cache Coherent Interconnect) driver.
* this init version clone from samsung exynos platform.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/init.h>
#include <linux/io.h>
#include <linux/errno.h>
#include <linux/cache.h>
#include <linux/syscore_ops.h>
#include <linux/delay.h>
#include <linux/kernel.h>
#include <asm/cacheflush.h>
#include <mach/cci.h>
#include <mach/platform.h>
#include <mach/cci-regs.h>
static void __iomem *cci_base;
static int cci_enabled __read_mostly;
void enable_cci_snoops(unsigned int cluster_id)
{
void __iomem *control_reg;
unsigned int value;
if (!cci_enabled) {
return;
}
/* pr_info("sunxi cci: enable cluster[%d] snoop\n", cluster_id); */
if (cluster_id) {
control_reg = CCI_A15_SL_IFACE(cci_base) + SNOOP_CTLR_REG;
} else {
control_reg = CCI_A7_SL_IFACE(cci_base) + SNOOP_CTLR_REG;
}
if ((readl(control_reg) & 0x3) == 0x3) {
/* cci snoop enable already */
return;
}
/* Turn on CCI snoops */
value = readl(control_reg);
value |= 0x3;
writel(value, control_reg);
dsb();
/* Wait for the dust to settle down */
while (readl(cci_base + STATUS_REG) & 0x1)
;
return;
}
void disable_cci_snoops(unsigned int cluster_id)
{
void __iomem *control_reg;
unsigned int value;
if (!cci_enabled) {
return;
}
if (cluster_id) {
control_reg = CCI_A15_SL_IFACE(cci_base) + SNOOP_CTLR_REG;
} else {
control_reg = CCI_A7_SL_IFACE(cci_base) + SNOOP_CTLR_REG;
}
if (!(readl(control_reg) & 0x3)) {
return;
}
/* Turn off CCI snoops */
value = readl(control_reg);
value &= (~0x3);
writel(value, control_reg);
dsb();
/* Wait for the dust to settle down */
while (readl(cci_base + STATUS_REG) & 0x1)
;
return;
}
/*
* Use our own MPIDR accessors as the generic ones in asm/cputype.h have
* __attribute_const__ and we don't want the compiler to assume any
* constness here.
*/
static int read_mpidr(void)
{
unsigned int id;
asm volatile ("mrc\tp15, 0, %0, c0, c0, 5" : "=r" (id));
return id;
}
#if defined(CONFIG_PM)
static int cci_status[2];
static int get_cci_snoop_status(unsigned int cluster_id)
{
void __iomem *control_reg;
if (!cci_enabled) {
return 0;
}
if (cluster_id) {
control_reg = CCI_A15_SL_IFACE(cci_base) + SNOOP_CTLR_REG;
} else {
control_reg = CCI_A7_SL_IFACE(cci_base) + SNOOP_CTLR_REG;
}
if ((readl(control_reg) & 0x3)) {
return 1;
}
return 0;
}
static int cci_suspend(void)
{
int i;
if (!cci_enabled) {
return 0;
}
for (i = 0; i < 2; i++) {
cci_status[i] = get_cci_snoop_status(i);
}
if (cci_status[0] && (!cci_status[1]))
disable_cci_snoops(0);
return 0;
}
static void cci_resume(void)
{
unsigned int cluster_id = (read_mpidr() >> 8) & 0xf;
if ((cluster_id != 0) && (cluster_id != 1)) {
pr_info("[%s]cluster id error! cluster id %d\n", __func__, cluster_id);
}
if (cci_enabled) {
if (cci_status[cluster_id]) {
enable_cci_snoops(cluster_id);
}
}
}
#else
#define cci_suspend NULL
#define cci_resume NULL
#endif
static struct syscore_ops cci_syscore_ops = {
.suspend = cci_suspend,
.resume = cci_resume,
};
int __init cci_init(void)
{
unsigned int cluster_id = (read_mpidr() >> 8) & 0xf;
#if defined(CONFIG_SUN8I_CCI)
cci_enabled = 1;
#endif
if (!cci_enabled) {
pr_info("sunxi cci is not supported\n");
goto disabled;
}
cci_base = (void __iomem *)(SUNXI_CCI400_VBASE);
enable_cci_snoops(cluster_id);
disabled:
register_syscore_ops(&cci_syscore_ops);
return 0;
}