alistair23-linux/arch/arm/mach-imx/cpu-imx5.c
Shawn Guo ee18a7154e ARM: imx5: retrieve iim base from device tree
Instead of using static define and mapping, the patch changes imx5 code
that reads chip revision from IIM to retrieve base address from device
tree and use dynamic mapping.

Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
2014-07-18 16:10:07 +08:00

128 lines
2.4 KiB
C

/*
* Copyright 2008-2010 Freescale Semiconductor, Inc. All Rights Reserved.
*
* The code contained herein is licensed under the GNU General Public
* License. You may obtain a copy of the GNU General Public License
* Version 2 or later at the following locations:
*
* http://www.opensource.org/licenses/gpl-license.html
* http://www.gnu.org/copyleft/gpl.html
*
* This file contains the CPU initialization code.
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include "hardware.h"
#include "common.h"
static int mx5_cpu_rev = -1;
#define IIM_SREV 0x24
static u32 imx5_read_srev_reg(const char *compat)
{
void __iomem *iim_base;
struct device_node *np;
u32 srev;
np = of_find_compatible_node(NULL, NULL, compat);
iim_base = of_iomap(np, 0);
WARN_ON(!iim_base);
srev = readl(iim_base + IIM_SREV) & 0xff;
iounmap(iim_base);
return srev;
}
static int get_mx51_srev(void)
{
u32 rev = imx5_read_srev_reg("fsl,imx51-iim");
switch (rev) {
case 0x0:
return IMX_CHIP_REVISION_2_0;
case 0x10:
return IMX_CHIP_REVISION_3_0;
default:
return IMX_CHIP_REVISION_UNKNOWN;
}
}
/*
* Returns:
* the silicon revision of the cpu
* -EINVAL - not a mx51
*/
int mx51_revision(void)
{
if (!cpu_is_mx51())
return -EINVAL;
if (mx5_cpu_rev == -1)
mx5_cpu_rev = get_mx51_srev();
return mx5_cpu_rev;
}
EXPORT_SYMBOL(mx51_revision);
#ifdef CONFIG_NEON
/*
* All versions of the silicon before Rev. 3 have broken NEON implementations.
* Dependent on link order - so the assumption is that vfp_init is called
* before us.
*/
int __init mx51_neon_fixup(void)
{
if (mx51_revision() < IMX_CHIP_REVISION_3_0 &&
(elf_hwcap & HWCAP_NEON)) {
elf_hwcap &= ~HWCAP_NEON;
pr_info("Turning off NEON support, detected broken NEON implementation\n");
}
return 0;
}
#endif
static int get_mx53_srev(void)
{
u32 rev = imx5_read_srev_reg("fsl,imx53-iim");
switch (rev) {
case 0x0:
return IMX_CHIP_REVISION_1_0;
case 0x2:
return IMX_CHIP_REVISION_2_0;
case 0x3:
return IMX_CHIP_REVISION_2_1;
default:
return IMX_CHIP_REVISION_UNKNOWN;
}
}
/*
* Returns:
* the silicon revision of the cpu
* -EINVAL - not a mx53
*/
int mx53_revision(void)
{
if (!cpu_is_mx53())
return -EINVAL;
if (mx5_cpu_rev == -1)
mx5_cpu_rev = get_mx53_srev();
return mx5_cpu_rev;
}
EXPORT_SYMBOL(mx53_revision);