kernel_optimize_test/arch/arm/mach-imx/cpu.c
Steffen Trumtrar e57e4ab5fc ARM: i.MX: allow disabling supervisor protect via DT
The i.MX SoCs allow to setup fine grained access rights to peripherals on the
AIPS bus.
This is done via the Peripheral Access Register (PAR) in e.g. the i.MX21
or in later SoC versions the Off-Platform Peripheral Access Control Register
(OPACR), e.g. i.MX53.
Under certain circumstances this leads to problems in which bus masters are
not granted their access rights to peripherals.
To be able to disable these restrictions on DT platforms, add a helper function
that looks for AIPS nodes in the DT and disables them for every compatible node
it finds.
The compatible has to be declared in the mach-specific entry file, where this
helper function should then be called.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
2014-07-18 16:11:39 +08:00

156 lines
3.1 KiB
C

#include <linux/err.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/slab.h>
#include <linux/sys_soc.h>
#include "hardware.h"
#include "common.h"
unsigned int __mxc_cpu_type;
EXPORT_SYMBOL(__mxc_cpu_type);
static unsigned int imx_soc_revision;
void mxc_set_cpu_type(unsigned int type)
{
__mxc_cpu_type = type;
}
void imx_set_soc_revision(unsigned int rev)
{
imx_soc_revision = rev;
}
unsigned int imx_get_soc_revision(void)
{
return imx_soc_revision;
}
void imx_print_silicon_rev(const char *cpu, int srev)
{
if (srev == IMX_CHIP_REVISION_UNKNOWN)
pr_info("CPU identified as %s, unknown revision\n", cpu);
else
pr_info("CPU identified as %s, silicon rev %d.%d\n",
cpu, (srev >> 4) & 0xf, srev & 0xf);
}
void __init imx_set_aips(void __iomem *base)
{
unsigned int reg;
/*
* Set all MPROTx to be non-bufferable, trusted for R/W,
* not forced to user-mode.
*/
__raw_writel(0x77777777, base + 0x0);
__raw_writel(0x77777777, base + 0x4);
/*
* Set all OPACRx to be non-bufferable, to not require
* supervisor privilege level for access, allow for
* write access and untrusted master access.
*/
__raw_writel(0x0, base + 0x40);
__raw_writel(0x0, base + 0x44);
__raw_writel(0x0, base + 0x48);
__raw_writel(0x0, base + 0x4C);
reg = __raw_readl(base + 0x50) & 0x00FFFFFF;
__raw_writel(reg, base + 0x50);
}
void __init imx_aips_allow_unprivileged_access(
const char *compat)
{
void __iomem *aips_base_addr;
struct device_node *np;
for_each_compatible_node(np, NULL, compat) {
aips_base_addr = of_iomap(np, 0);
imx_set_aips(aips_base_addr);
}
}
struct device * __init imx_soc_device_init(void)
{
struct soc_device_attribute *soc_dev_attr;
struct soc_device *soc_dev;
struct device_node *root;
const char *soc_id;
int ret;
soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
if (!soc_dev_attr)
return NULL;
soc_dev_attr->family = "Freescale i.MX";
root = of_find_node_by_path("/");
ret = of_property_read_string(root, "model", &soc_dev_attr->machine);
of_node_put(root);
if (ret)
goto free_soc;
switch (__mxc_cpu_type) {
case MXC_CPU_MX1:
soc_id = "i.MX1";
break;
case MXC_CPU_MX21:
soc_id = "i.MX21";
break;
case MXC_CPU_MX25:
soc_id = "i.MX25";
break;
case MXC_CPU_MX27:
soc_id = "i.MX27";
break;
case MXC_CPU_MX31:
soc_id = "i.MX31";
break;
case MXC_CPU_MX35:
soc_id = "i.MX35";
break;
case MXC_CPU_MX51:
soc_id = "i.MX51";
break;
case MXC_CPU_MX53:
soc_id = "i.MX53";
break;
case MXC_CPU_IMX6SL:
soc_id = "i.MX6SL";
break;
case MXC_CPU_IMX6DL:
soc_id = "i.MX6DL";
break;
case MXC_CPU_IMX6SX:
soc_id = "i.MX6SX";
break;
case MXC_CPU_IMX6Q:
soc_id = "i.MX6Q";
break;
default:
soc_id = "Unknown";
}
soc_dev_attr->soc_id = soc_id;
soc_dev_attr->revision = kasprintf(GFP_KERNEL, "%d.%d",
(imx_soc_revision >> 4) & 0xf,
imx_soc_revision & 0xf);
if (!soc_dev_attr->revision)
goto free_soc;
soc_dev = soc_device_register(soc_dev_attr);
if (IS_ERR(soc_dev))
goto free_rev;
return soc_device_to_device(soc_dev);
free_rev:
kfree(soc_dev_attr->revision);
free_soc:
kfree(soc_dev_attr);
return NULL;
}