kernel_optimize_test/arch/arm/mach-tegra/pm.c
Dmitry Osipenko 38743e414e ARM: tegra: Do not fully reinitialize L2 on resume
ASUS TF300T device may not work properly if firmware is asked to fully
re-initialize L2 cache after resume from LP2 suspend. The downstream
kernel of TF300T uses different opcode to enable cache after resuming
from LP2, this opcode also works fine on Nexus 7 and Ouya devices.
Supposedly, this may be needed by an older firmware versions.

Reported-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Tested-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Tested-by: Jasper Korten <jja2000@gmail.com>
Tested-by: David Heidelberg <david@ixit.cz>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2020-05-06 18:29:05 +02:00

454 lines
9.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* CPU complex suspend & resume functions for Tegra SoCs
*
* Copyright (c) 2009-2012, NVIDIA Corporation. All rights reserved.
*/
#include <linux/clk/tegra.h>
#include <linux/cpumask.h>
#include <linux/cpu_pm.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/suspend.h>
#include <linux/firmware/trusted_foundations.h>
#include <soc/tegra/flowctrl.h>
#include <soc/tegra/fuse.h>
#include <soc/tegra/pm.h>
#include <soc/tegra/pmc.h>
#include <asm/cacheflush.h>
#include <asm/firmware.h>
#include <asm/idmap.h>
#include <asm/proc-fns.h>
#include <asm/smp_plat.h>
#include <asm/suspend.h>
#include <asm/tlbflush.h>
#include "iomap.h"
#include "pm.h"
#include "reset.h"
#include "sleep.h"
#ifdef CONFIG_PM_SLEEP
static DEFINE_SPINLOCK(tegra_lp2_lock);
static u32 iram_save_size;
static void *iram_save_addr;
struct tegra_lp1_iram tegra_lp1_iram;
void (*tegra_tear_down_cpu)(void);
void (*tegra_sleep_core_finish)(unsigned long v2p);
static int (*tegra_sleep_func)(unsigned long v2p);
static void tegra_tear_down_cpu_init(void)
{
switch (tegra_get_chip_id()) {
case TEGRA20:
if (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC))
tegra_tear_down_cpu = tegra20_tear_down_cpu;
break;
case TEGRA30:
case TEGRA114:
case TEGRA124:
if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC) ||
IS_ENABLED(CONFIG_ARCH_TEGRA_114_SOC) ||
IS_ENABLED(CONFIG_ARCH_TEGRA_124_SOC))
tegra_tear_down_cpu = tegra30_tear_down_cpu;
break;
}
}
/*
* restore_cpu_complex
*
* restores cpu clock setting, clears flow controller
*
* Always called on CPU 0.
*/
static void restore_cpu_complex(void)
{
int cpu = smp_processor_id();
BUG_ON(cpu != 0);
#ifdef CONFIG_SMP
cpu = cpu_logical_map(cpu);
#endif
/* Restore the CPU clock settings */
tegra_cpu_clock_resume();
flowctrl_cpu_suspend_exit(cpu);
}
/*
* suspend_cpu_complex
*
* saves pll state for use by restart_plls, prepares flow controller for
* transition to suspend state
*
* Must always be called on cpu 0.
*/
static void suspend_cpu_complex(void)
{
int cpu = smp_processor_id();
BUG_ON(cpu != 0);
#ifdef CONFIG_SMP
cpu = cpu_logical_map(cpu);
#endif
/* Save the CPU clock settings */
tegra_cpu_clock_suspend();
flowctrl_cpu_suspend_enter(cpu);
}
void tegra_pm_clear_cpu_in_lp2(void)
{
int phy_cpu_id = cpu_logical_map(smp_processor_id());
u32 *cpu_in_lp2 = tegra_cpu_lp2_mask;
spin_lock(&tegra_lp2_lock);
BUG_ON(!(*cpu_in_lp2 & BIT(phy_cpu_id)));
*cpu_in_lp2 &= ~BIT(phy_cpu_id);
spin_unlock(&tegra_lp2_lock);
}
void tegra_pm_set_cpu_in_lp2(void)
{
int phy_cpu_id = cpu_logical_map(smp_processor_id());
u32 *cpu_in_lp2 = tegra_cpu_lp2_mask;
spin_lock(&tegra_lp2_lock);
BUG_ON((*cpu_in_lp2 & BIT(phy_cpu_id)));
*cpu_in_lp2 |= BIT(phy_cpu_id);
spin_unlock(&tegra_lp2_lock);
}
static int tegra_sleep_cpu(unsigned long v2p)
{
if (tegra_cpu_car_ops->rail_off_ready &&
WARN_ON(!tegra_cpu_rail_off_ready()))
return -EBUSY;
/*
* L2 cache disabling using kernel API only allowed when all
* secondary CPU's are offline. Cache have to be disabled with
* MMU-on if cache maintenance is done via Trusted Foundations
* firmware. Note that CPUIDLE won't ever enter powergate on Tegra30
* if any of secondary CPU's is online and this is the LP2-idle
* code-path only for Tegra20/30.
*/
#ifdef CONFIG_OUTER_CACHE
if (trusted_foundations_registered() && outer_cache.disable)
outer_cache.disable();
#endif
/*
* Note that besides of setting up CPU reset vector this firmware
* call may also do the following, depending on the FW version:
* 1) Disable L2. But this doesn't matter since we already
* disabled the L2.
* 2) Disable D-cache. This need to be taken into account in
* particular by the tegra_disable_clean_inv_dcache() which
* shall avoid the re-disable.
*/
call_firmware_op(prepare_idle, TF_PM_MODE_LP2);
setup_mm_for_reboot();
tegra_sleep_cpu_finish(v2p);
/* should never here */
BUG();
return 0;
}
static void tegra_pm_set(enum tegra_suspend_mode mode)
{
u32 value;
switch (tegra_get_chip_id()) {
case TEGRA20:
case TEGRA30:
break;
default:
/* Turn off CRAIL */
value = flowctrl_read_cpu_csr(0);
value &= ~FLOW_CTRL_CSR_ENABLE_EXT_MASK;
value |= FLOW_CTRL_CSR_ENABLE_EXT_CRAIL;
flowctrl_write_cpu_csr(0, value);
break;
}
tegra_pmc_enter_suspend_mode(mode);
}
int tegra_pm_enter_lp2(void)
{
int err;
tegra_pm_set(TEGRA_SUSPEND_LP2);
cpu_cluster_pm_enter();
suspend_cpu_complex();
err = cpu_suspend(PHYS_OFFSET - PAGE_OFFSET, &tegra_sleep_cpu);
/*
* Resume L2 cache if it wasn't re-enabled early during resume,
* which is the case for Tegra30 that has to re-enable the cache
* via firmware call. In other cases cache is already enabled and
* hence re-enabling is a no-op. This is always a no-op on Tegra114+.
*/
outer_resume();
restore_cpu_complex();
cpu_cluster_pm_exit();
call_firmware_op(prepare_idle, TF_PM_MODE_NONE);
return err;
}
enum tegra_suspend_mode tegra_pm_validate_suspend_mode(
enum tegra_suspend_mode mode)
{
/*
* The Tegra devices support suspending to LP1 or lower currently.
*/
if (mode > TEGRA_SUSPEND_LP1)
return TEGRA_SUSPEND_LP1;
return mode;
}
static int tegra_sleep_core(unsigned long v2p)
{
/*
* Cache have to be disabled with MMU-on if cache maintenance is done
* via Trusted Foundations firmware. This is a no-op on Tegra114+.
*/
if (trusted_foundations_registered())
outer_disable();
call_firmware_op(prepare_idle, TF_PM_MODE_LP1);
setup_mm_for_reboot();
tegra_sleep_core_finish(v2p);
/* should never here */
BUG();
return 0;
}
/*
* tegra_lp1_iram_hook
*
* Hooking the address of LP1 reset vector and SDRAM self-refresh code in
* SDRAM. These codes not be copied to IRAM in this fuction. We need to
* copy these code to IRAM before LP0/LP1 suspend and restore the content
* of IRAM after resume.
*/
static bool tegra_lp1_iram_hook(void)
{
switch (tegra_get_chip_id()) {
case TEGRA20:
if (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC))
tegra20_lp1_iram_hook();
break;
case TEGRA30:
case TEGRA114:
case TEGRA124:
if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC) ||
IS_ENABLED(CONFIG_ARCH_TEGRA_114_SOC) ||
IS_ENABLED(CONFIG_ARCH_TEGRA_124_SOC))
tegra30_lp1_iram_hook();
break;
default:
break;
}
if (!tegra_lp1_iram.start_addr || !tegra_lp1_iram.end_addr)
return false;
iram_save_size = tegra_lp1_iram.end_addr - tegra_lp1_iram.start_addr;
iram_save_addr = kmalloc(iram_save_size, GFP_KERNEL);
if (!iram_save_addr)
return false;
return true;
}
static bool tegra_sleep_core_init(void)
{
switch (tegra_get_chip_id()) {
case TEGRA20:
if (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC))
tegra20_sleep_core_init();
break;
case TEGRA30:
case TEGRA114:
case TEGRA124:
if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC) ||
IS_ENABLED(CONFIG_ARCH_TEGRA_114_SOC) ||
IS_ENABLED(CONFIG_ARCH_TEGRA_124_SOC))
tegra30_sleep_core_init();
break;
default:
break;
}
if (!tegra_sleep_core_finish)
return false;
return true;
}
static void tegra_suspend_enter_lp1(void)
{
/* copy the reset vector & SDRAM shutdown code into IRAM */
memcpy(iram_save_addr, IO_ADDRESS(TEGRA_IRAM_LPx_RESUME_AREA),
iram_save_size);
memcpy(IO_ADDRESS(TEGRA_IRAM_LPx_RESUME_AREA),
tegra_lp1_iram.start_addr, iram_save_size);
*((u32 *)tegra_cpu_lp1_mask) = 1;
}
static void tegra_suspend_exit_lp1(void)
{
/* restore IRAM */
memcpy(IO_ADDRESS(TEGRA_IRAM_LPx_RESUME_AREA), iram_save_addr,
iram_save_size);
*(u32 *)tegra_cpu_lp1_mask = 0;
}
static const char *lp_state[TEGRA_MAX_SUSPEND_MODE] = {
[TEGRA_SUSPEND_NONE] = "none",
[TEGRA_SUSPEND_LP2] = "LP2",
[TEGRA_SUSPEND_LP1] = "LP1",
[TEGRA_SUSPEND_LP0] = "LP0",
};
static int tegra_suspend_enter(suspend_state_t state)
{
enum tegra_suspend_mode mode = tegra_pmc_get_suspend_mode();
if (WARN_ON(mode < TEGRA_SUSPEND_NONE ||
mode >= TEGRA_MAX_SUSPEND_MODE))
return -EINVAL;
pr_info("Entering suspend state %s\n", lp_state[mode]);
tegra_pm_set(mode);
local_fiq_disable();
suspend_cpu_complex();
switch (mode) {
case TEGRA_SUSPEND_LP1:
tegra_suspend_enter_lp1();
break;
case TEGRA_SUSPEND_LP2:
tegra_pm_set_cpu_in_lp2();
break;
default:
break;
}
cpu_suspend(PHYS_OFFSET - PAGE_OFFSET, tegra_sleep_func);
/*
* Resume L2 cache if it wasn't re-enabled early during resume,
* which is the case for Tegra30 that has to re-enable the cache
* via firmware call. In other cases cache is already enabled and
* hence re-enabling is a no-op.
*/
outer_resume();
switch (mode) {
case TEGRA_SUSPEND_LP1:
tegra_suspend_exit_lp1();
break;
case TEGRA_SUSPEND_LP2:
tegra_pm_clear_cpu_in_lp2();
break;
default:
break;
}
restore_cpu_complex();
local_fiq_enable();
call_firmware_op(prepare_idle, TF_PM_MODE_NONE);
return 0;
}
static const struct platform_suspend_ops tegra_suspend_ops = {
.valid = suspend_valid_only_mem,
.enter = tegra_suspend_enter,
};
void __init tegra_init_suspend(void)
{
enum tegra_suspend_mode mode = tegra_pmc_get_suspend_mode();
if (mode == TEGRA_SUSPEND_NONE)
return;
tegra_tear_down_cpu_init();
if (mode >= TEGRA_SUSPEND_LP1) {
if (!tegra_lp1_iram_hook() || !tegra_sleep_core_init()) {
pr_err("%s: unable to allocate memory for SDRAM"
"self-refresh -- LP0/LP1 unavailable\n",
__func__);
tegra_pmc_set_suspend_mode(TEGRA_SUSPEND_LP2);
mode = TEGRA_SUSPEND_LP2;
}
}
/* set up sleep function for cpu_suspend */
switch (mode) {
case TEGRA_SUSPEND_LP1:
tegra_sleep_func = tegra_sleep_core;
break;
case TEGRA_SUSPEND_LP2:
tegra_sleep_func = tegra_sleep_cpu;
break;
default:
break;
}
suspend_set_ops(&tegra_suspend_ops);
}
int tegra_pm_park_secondary_cpu(unsigned long cpu)
{
if (cpu > 0) {
tegra_disable_clean_inv_dcache(TEGRA_FLUSH_CACHE_LOUIS);
if (tegra_get_chip_id() == TEGRA20)
tegra20_hotplug_shutdown();
else
tegra30_hotplug_shutdown();
}
return -EINVAL;
}
#endif