mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-29 14:05:19 +08:00
26b754f994
On i.MX51/i.MX53 it is necessary to set the DBGEN bit in ARM_GPC register in order to turn on the debug clocks. The DBGEN bit of ARM_GPC register has the following description in the i.MX53 Reference Manual: "This allows the user to manually activate clocks within the debug system. This register bit directly controls the platform's dbgen_out output signal which connects to the DAP_SYS to enable all debug clocks. Once enabled, the clocks cannot be disabled except by asserting the disable_trace input of the DAP_SYS." Based on a previous patch from Sebastian Reichel. Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
165 lines
3.2 KiB
C
165 lines
3.2 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
|
|
*/
|
|
int mx51_revision(void)
|
|
{
|
|
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
|
|
*/
|
|
int mx53_revision(void)
|
|
{
|
|
if (mx5_cpu_rev == -1)
|
|
mx5_cpu_rev = get_mx53_srev();
|
|
|
|
return mx5_cpu_rev;
|
|
}
|
|
EXPORT_SYMBOL(mx53_revision);
|
|
|
|
#define ARM_GPC 0x4
|
|
#define DBGEN BIT(16)
|
|
|
|
/*
|
|
* This enables the DBGEN bit in ARM_GPC register, which is
|
|
* required for accessing some performance counter features.
|
|
* Technically it is only required while perf is used, but to
|
|
* keep the source code simple we just enable it all the time
|
|
* when the kernel configuration allows using the feature.
|
|
*/
|
|
void __init imx5_pmu_init(void)
|
|
{
|
|
void __iomem *tigerp_base;
|
|
struct device_node *np;
|
|
u32 gpc;
|
|
|
|
if (!IS_ENABLED(CONFIG_ARM_PMU))
|
|
return;
|
|
|
|
np = of_find_compatible_node(NULL, NULL, "arm,cortex-a8-pmu");
|
|
if (!np)
|
|
return;
|
|
|
|
if (!of_property_read_bool(np, "secure-reg-access"))
|
|
goto exit;
|
|
|
|
of_node_put(np);
|
|
|
|
np = of_find_compatible_node(NULL, NULL, "fsl,imx51-tigerp");
|
|
if (!np)
|
|
return;
|
|
|
|
tigerp_base = of_iomap(np, 0);
|
|
if (!tigerp_base)
|
|
goto exit;
|
|
|
|
gpc = readl_relaxed(tigerp_base + ARM_GPC);
|
|
gpc |= DBGEN;
|
|
writel_relaxed(gpc, tigerp_base + ARM_GPC);
|
|
iounmap(tigerp_base);
|
|
exit:
|
|
of_node_put(np);
|
|
|
|
}
|