linux/arch/arm/mach-tegra/platsmp.c

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/*
* linux/arch/arm/mach-tegra/platsmp.c
*
* Copyright (C) 2002 ARM Ltd.
* All Rights Reserved
*
* Copyright (C) 2009 Palm
* All Rights Reserved
*
* 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.
*/
#include <linux/clk/tegra.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/jiffies.h>
#include <linux/smp.h>
#include <soc/tegra/fuse.h>
#include <asm/cacheflush.h>
#include <asm/mach-types.h>
#include <asm/smp_plat.h>
#include <asm/smp_scu.h>
#include "common.h"
#include "flowctrl.h"
#include "iomap.h"
#include "pmc.h"
#include "reset.h"
static cpumask_t tegra_cpu_init_mask;
arm: delete __cpuinit/__CPUINIT usage from all ARM users The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) and are flagged as __cpuinit -- so if we remove the __cpuinit from the arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit related content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the ARM uses of the __cpuinit macros from C code, and all __CPUINIT from assembly code. It also had two ".previous" section statements that were paired off against __CPUINIT (aka .section ".cpuinit.text") that also get removed here. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Russell King <linux@arm.linux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-06-17 19:43:14 +00:00
static void tegra_secondary_init(unsigned int cpu)
{
cpumask_set_cpu(cpu, &tegra_cpu_init_mask);
}
static int tegra20_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
cpu = cpu_logical_map(cpu);
/*
* Force the CPU into reset. The CPU must remain in reset when
* the flow controller state is cleared (which will cause the
* flow controller to stop driving reset if the CPU has been
* power-gated via the flow controller). This will have no
* effect on first boot of the CPU since it should already be
* in reset.
*/
tegra_put_cpu_in_reset(cpu);
/*
* Unhalt the CPU. If the flow controller was used to
* power-gate the CPU this will cause the flow controller to
* stop driving reset. The CPU will remain in reset because the
* clock and reset block is now driving reset.
*/
flowctrl_write_cpu_halt(cpu, 0);
tegra_enable_cpu_clock(cpu);
flowctrl_write_cpu_csr(cpu, 0); /* Clear flow controller CSR. */
tegra_cpu_out_of_reset(cpu);
return 0;
}
static int tegra30_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
int ret;
unsigned long timeout;
cpu = cpu_logical_map(cpu);
tegra_put_cpu_in_reset(cpu);
flowctrl_write_cpu_halt(cpu, 0);
/*
* The power up sequence of cold boot CPU and warm boot CPU
* was different.
*
* For warm boot CPU that was resumed from CPU hotplug, the
* power will be resumed automatically after un-halting the
* flow controller of the warm boot CPU. We need to wait for
* the confirmaiton that the CPU is powered then removing
* the IO clamps.
* For cold boot CPU, do not wait. After the cold boot CPU be
* booted, it will run to tegra_secondary_init() and set
* tegra_cpu_init_mask which influences what tegra30_boot_secondary()
* next time around.
*/
if (cpumask_test_cpu(cpu, &tegra_cpu_init_mask)) {
timeout = jiffies + msecs_to_jiffies(50);
do {
if (tegra_pmc_cpu_is_powered(cpu))
goto remove_clamps;
udelay(10);
} while (time_before(jiffies, timeout));
}
/*
* The power status of the cold boot CPU is power gated as
* default. To power up the cold boot CPU, the power should
* be un-gated by un-toggling the power gate register
* manually.
*/
if (!tegra_pmc_cpu_is_powered(cpu)) {
ret = tegra_pmc_cpu_power_on(cpu);
if (ret)
return ret;
/* Wait for the power to come up. */
timeout = jiffies + msecs_to_jiffies(100);
while (!tegra_pmc_cpu_is_powered(cpu)) {
if (time_after(jiffies, timeout))
return -ETIMEDOUT;
udelay(10);
}
}
remove_clamps:
/* CPU partition is powered. Enable the CPU clock. */
tegra_enable_cpu_clock(cpu);
udelay(10);
/* Remove I/O clamps. */
ret = tegra_pmc_cpu_remove_clamping(cpu);
if (ret)
return ret;
udelay(10);
flowctrl_write_cpu_csr(cpu, 0); /* Clear flow controller CSR. */
tegra_cpu_out_of_reset(cpu);
return 0;
}
static int tegra114_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
int ret = 0;
cpu = cpu_logical_map(cpu);
if (cpumask_test_cpu(cpu, &tegra_cpu_init_mask)) {
/*
* Warm boot flow
* The flow controller in charge of the power state and
* control for each CPU.
*/
/* set SCLK as event trigger for flow controller */
flowctrl_write_cpu_csr(cpu, 1);
flowctrl_write_cpu_halt(cpu,
FLOW_CTRL_WAITEVENT | FLOW_CTRL_SCLK_RESUME);
} else {
/*
* Cold boot flow
* The CPU is powered up by toggling PMC directly. It will
* also initial power state in flow controller. After that,
* the CPU's power state is maintained by flow controller.
*/
ret = tegra_pmc_cpu_power_on(cpu);
}
return ret;
}
arm: delete __cpuinit/__CPUINIT usage from all ARM users The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) and are flagged as __cpuinit -- so if we remove the __cpuinit from the arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit related content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the ARM uses of the __cpuinit macros from C code, and all __CPUINIT from assembly code. It also had two ".previous" section statements that were paired off against __CPUINIT (aka .section ".cpuinit.text") that also get removed here. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Russell King <linux@arm.linux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-06-17 19:43:14 +00:00
static int tegra_boot_secondary(unsigned int cpu,
struct task_struct *idle)
{
if (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC) && tegra_get_chip_id() == TEGRA20)
return tegra20_boot_secondary(cpu, idle);
if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC) && tegra_get_chip_id() == TEGRA30)
return tegra30_boot_secondary(cpu, idle);
if (IS_ENABLED(CONFIG_ARCH_TEGRA_114_SOC) && tegra_get_chip_id() == TEGRA114)
return tegra114_boot_secondary(cpu, idle);
if (IS_ENABLED(CONFIG_ARCH_TEGRA_124_SOC) && tegra_get_chip_id() == TEGRA124)
return tegra114_boot_secondary(cpu, idle);
return -EINVAL;
}
static void __init tegra_smp_prepare_cpus(unsigned int max_cpus)
{
/* Always mark the boot CPU (CPU0) as initialized. */
cpumask_set_cpu(0, &tegra_cpu_init_mask);
if (scu_a9_has_base())
scu_enable(IO_ADDRESS(scu_a9_get_base()));
}
struct smp_operations tegra_smp_ops __initdata = {
.smp_prepare_cpus = tegra_smp_prepare_cpus,
.smp_secondary_init = tegra_secondary_init,
.smp_boot_secondary = tegra_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_kill = tegra_cpu_kill,
.cpu_die = tegra_cpu_die,
#endif
};