u-boot/arch/arm/lib/cache-cp15.c
Heiko Schocher f1d2b313c9 ARM: add relocation support
!! This breaks support for all arm boards !!

To compile in old style, you must define
CONFIG_SYS_ARM_WITHOUT_RELOC or you can compile
with "CONFIG_SYS_ARM_WITHOUT_RELOC=1 ./MAKEALL board"

!! This define will be removed soon, so convert your
board to use relocation support

Portions of this work were supported by funding from
the CE Linux Forum.

Signed-off-by: Heiko Schocher <hs@denx.de>

Fix boot from NAND for non-ARM systems
Signed-off-by: Wolfgang Denk <wd@denx.de>
2010-09-19 19:29:53 +02:00

202 lines
4.2 KiB
C

/*
* (C) Copyright 2002
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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.
*
* 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 <common.h>
#include <asm/system.h>
#if !(defined(CONFIG_SYS_NO_ICACHE) && defined(CONFIG_SYS_NO_DCACHE))
#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
#define CACHE_SETUP 0x1a
#else
#define CACHE_SETUP 0x1e
#endif
DECLARE_GLOBAL_DATA_PTR;
static void cp_delay (void)
{
volatile int i;
/* copro seems to need some delay between reading and writing */
for (i = 0; i < 100; i++)
nop();
asm volatile("" : : : "memory");
}
#if !defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
static inline void dram_bank_mmu_setup(int bank)
{
u32 *page_table = (u32 *)gd->tlb_addr;
bd_t *bd = gd->bd;
int i;
debug("%s: bank: %d\n", __func__, bank);
for (i = bd->bi_dram[bank].start >> 20;
i < (bd->bi_dram[bank].start + bd->bi_dram[bank].size) >> 20;
i++) {
page_table[i] = i << 20 | (3 << 10) | CACHE_SETUP;
}
}
#endif
/* to activate the MMU we need to set up virtual memory: use 1M areas */
static inline void mmu_setup(void)
{
#if !defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
u32 *page_table = (u32 *)gd->tlb_addr;
#else
static u32 __attribute__((aligned(16384))) page_table[4096];
bd_t *bd = gd->bd;
int j;
#endif
int i;
u32 reg;
/* Set up an identity-mapping for all 4GB, rw for everyone */
for (i = 0; i < 4096; i++)
page_table[i] = i << 20 | (3 << 10) | 0x12;
#if !defined(CONFIG_SYS_ARM_WITHOUT_RELOC)
for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
dram_bank_mmu_setup(i);
}
#else
/* Then, enable cacheable and bufferable for RAM only */
for (j = 0; j < CONFIG_NR_DRAM_BANKS; j++) {
for (i = bd->bi_dram[j].start >> 20;
i < (bd->bi_dram[j].start + bd->bi_dram[j].size) >> 20;
i++) {
page_table[i] = i << 20 | (3 << 10) | CACHE_SETUP;
}
}
#endif
/* Copy the page table address to cp15 */
asm volatile("mcr p15, 0, %0, c2, c0, 0"
: : "r" (page_table) : "memory");
/* Set the access control to all-supervisor */
asm volatile("mcr p15, 0, %0, c3, c0, 0"
: : "r" (~0));
/* and enable the mmu */
reg = get_cr(); /* get control reg. */
cp_delay();
set_cr(reg | CR_M);
}
/* cache_bit must be either CR_I or CR_C */
static void cache_enable(uint32_t cache_bit)
{
uint32_t reg;
/* The data cache is not active unless the mmu is enabled too */
if (cache_bit == CR_C)
mmu_setup();
reg = get_cr(); /* get control reg. */
cp_delay();
set_cr(reg | cache_bit);
}
/* cache_bit must be either CR_I or CR_C */
static void cache_disable(uint32_t cache_bit)
{
uint32_t reg;
if (cache_bit == CR_C) {
/* if cache isn;t enabled no need to disable */
reg = get_cr();
if ((reg & CR_C) != CR_C)
return;
/* if disabling data cache, disable mmu too */
cache_bit |= CR_M;
flush_cache(0, ~0);
}
reg = get_cr();
cp_delay();
set_cr(reg & ~cache_bit);
}
#endif
#ifdef CONFIG_SYS_NO_ICACHE
void icache_enable (void)
{
return;
}
void icache_disable (void)
{
return;
}
int icache_status (void)
{
return 0; /* always off */
}
#else
void icache_enable(void)
{
cache_enable(CR_I);
}
void icache_disable(void)
{
cache_disable(CR_I);
}
int icache_status(void)
{
return (get_cr() & CR_I) != 0;
}
#endif
#ifdef CONFIG_SYS_NO_DCACHE
void dcache_enable (void)
{
return;
}
void dcache_disable (void)
{
return;
}
int dcache_status (void)
{
return 0; /* always off */
}
#else
void dcache_enable(void)
{
cache_enable(CR_C);
}
void dcache_disable(void)
{
cache_disable(CR_C);
}
int dcache_status(void)
{
return (get_cr() & CR_C) != 0;
}
#endif