linux/arch/arm/mm/cache-l2x0.c
Srinidhi Kasagar 48371cd3f4 ARM: 5845/1: l2x0: check whether l2x0 already enabled
If running in non-secure mode accessing
some registers of l2x0 will fault. So
check if l2x0 is already enabled, if so
do not access those secure registers.

Signed-off-by: srinidhi kasagar <srinidhi.kasagar@stericsson.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-12-03 19:42:30 +00:00

128 lines
3.2 KiB
C

/*
* arch/arm/mm/cache-l2x0.c - L210/L220 cache controller support
*
* Copyright (C) 2007 ARM Limited
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#include <asm/cacheflush.h>
#include <asm/hardware/cache-l2x0.h>
#define CACHE_LINE_SIZE 32
static void __iomem *l2x0_base;
static DEFINE_SPINLOCK(l2x0_lock);
static inline void sync_writel(unsigned long val, unsigned long reg,
unsigned long complete_mask)
{
unsigned long flags;
spin_lock_irqsave(&l2x0_lock, flags);
writel(val, l2x0_base + reg);
/* wait for the operation to complete */
while (readl(l2x0_base + reg) & complete_mask)
;
spin_unlock_irqrestore(&l2x0_lock, flags);
}
static inline void cache_sync(void)
{
sync_writel(0, L2X0_CACHE_SYNC, 1);
}
static inline void l2x0_inv_all(void)
{
/* invalidate all ways */
sync_writel(0xff, L2X0_INV_WAY, 0xff);
cache_sync();
}
static void l2x0_inv_range(unsigned long start, unsigned long end)
{
unsigned long addr;
if (start & (CACHE_LINE_SIZE - 1)) {
start &= ~(CACHE_LINE_SIZE - 1);
sync_writel(start, L2X0_CLEAN_INV_LINE_PA, 1);
start += CACHE_LINE_SIZE;
}
if (end & (CACHE_LINE_SIZE - 1)) {
end &= ~(CACHE_LINE_SIZE - 1);
sync_writel(end, L2X0_CLEAN_INV_LINE_PA, 1);
}
for (addr = start; addr < end; addr += CACHE_LINE_SIZE)
sync_writel(addr, L2X0_INV_LINE_PA, 1);
cache_sync();
}
static void l2x0_clean_range(unsigned long start, unsigned long end)
{
unsigned long addr;
start &= ~(CACHE_LINE_SIZE - 1);
for (addr = start; addr < end; addr += CACHE_LINE_SIZE)
sync_writel(addr, L2X0_CLEAN_LINE_PA, 1);
cache_sync();
}
static void l2x0_flush_range(unsigned long start, unsigned long end)
{
unsigned long addr;
start &= ~(CACHE_LINE_SIZE - 1);
for (addr = start; addr < end; addr += CACHE_LINE_SIZE)
sync_writel(addr, L2X0_CLEAN_INV_LINE_PA, 1);
cache_sync();
}
void __init l2x0_init(void __iomem *base, __u32 aux_val, __u32 aux_mask)
{
__u32 aux;
l2x0_base = base;
/*
* Check if l2x0 controller is already enabled.
* If you are booting from non-secure mode
* accessing the below registers will fault.
*/
if (!(readl(l2x0_base + L2X0_CTRL) & 1)) {
/* l2x0 controller is disabled */
aux = readl(l2x0_base + L2X0_AUX_CTRL);
aux &= aux_mask;
aux |= aux_val;
writel(aux, l2x0_base + L2X0_AUX_CTRL);
l2x0_inv_all();
/* enable L2X0 */
writel(1, l2x0_base + L2X0_CTRL);
}
outer_cache.inv_range = l2x0_inv_range;
outer_cache.clean_range = l2x0_clean_range;
outer_cache.flush_range = l2x0_flush_range;
printk(KERN_INFO "L2X0 cache controller enabled\n");
}