// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2015 Carlo Caione <[email protected]>
* Copyright (C) 2017 Martin Blumenstingl <[email protected]>
*/
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/smp.h>
#include <linux/mfd/syscon.h>
#include <asm/cacheflush.h>
#include <asm/cp15.h>
#include <asm/smp_scu.h>
#include <asm/smp_plat.h>
#define MESON_SMP_SRAM_CPU_CTRL_REG (0x00)
#define MESON_SMP_SRAM_CPU_CTRL_ADDR_REG(c) (0x04 + ((c - 1) << 2))
#define MESON_CPU_AO_RTI_PWR_A9_CNTL0 (0x00)
#define MESON_CPU_AO_RTI_PWR_A9_CNTL1 (0x04)
#define MESON_CPU_AO_RTI_PWR_A9_MEM_PD0 (0x14)
#define MESON_CPU_PWR_A9_CNTL0_M(c) (0x03 << ((c * 2) + 16))
#define MESON_CPU_PWR_A9_CNTL1_M(c) (0x03 << ((c + 1) << 1))
#define MESON_CPU_PWR_A9_MEM_PD0_M(c) (0x0f << (32 - (c * 4)))
#define MESON_CPU_PWR_A9_CNTL1_ST(c) (0x01 << (c + 16))
static void __iomem *sram_base;
static void __iomem *scu_base;
static struct regmap *pmu;
static struct reset_control *meson_smp_get_core_reset(int cpu)
{
struct device_node *np = of_get_cpu_node(cpu, 0);
return of_reset_control_get_exclusive(np, NULL);
}
static void meson_smp_set_cpu_ctrl(int cpu, bool on_off)
{
u32 val = readl(sram_base + MESON_SMP_SRAM_CPU_CTRL_REG);
if (on_off)
val |= BIT(cpu);
else
val &= ~BIT(cpu);
/* keep bit 0 always enabled */
val |= BIT(0);
writel(val, sram_base + MESON_SMP_SRAM_CPU_CTRL_REG);
}
static void __init meson_smp_prepare_cpus(const char *scu_compatible,
const char *pmu_compatible,
const char *sram_compatible)
{
static struct device_node *node;
/* SMP SRAM */
node = of_find_compatible_node(NULL, NULL, sram_compatible);
if (!node) {
pr_err("Missing SRAM node\n");
return;
}
sram_base = of_iomap(node, 0);
of_node_put(node);
if (!sram_base) {
pr_err("Couldn't map SRAM registers\n");
return;
}
/* PMU */
pmu = syscon_regmap_lookup_by_compatible(pmu_compatible);
if (IS_ERR(pmu)) {
pr_err("Couldn't map PMU registers\n");
return;
}
/* SCU */
node = of_find_compatible_node(NULL, NULL, scu_compatible);
if (!node) {
pr_err("Missing SCU node\n");
return;
}
scu_base = of_iomap(node, 0);
of_node_put(node);
if (!scu_base) {
pr_err("Couldn't map SCU registers\n");
return;
}
scu_enable(scu_base);
}
static void __init meson8b_smp_prepare_cpus(unsigned int max_cpus)
{
meson_smp_prepare_cpus("arm,cortex-a5-scu", "amlogic,meson8b-pmu",
"amlogic,meson8b-smp-sram");
}
static void __init meson8_smp_prepare_cpus(unsigned int max_cpus)
{
meson_smp_prepare_cpus("arm,cortex-a9-scu", "amlogic,meson8-pmu",
"amlogic,meson8-smp-sram");
}
static void meson_smp_begin_secondary_boot(unsigned int cpu)
{
/*
* Set the entry point before powering on the CPU through the SCU. This
* is needed if the CPU is in "warm" state (= after rebooting the
* system without power-cycling, or when taking the CPU offline and
* then taking it online again.
*/
writel(__pa_symbol(secondary_startup),
sram_base + MESON_SMP_SRAM_CPU_CTRL_ADDR_REG(cpu));
/*
* SCU Power on CPU (needs to be done before starting the CPU,
* otherwise the secondary CPU will not start).
*/
scu_cpu_power_enable(scu_base, cpu);
}
static int meson_smp_finalize_secondary_boot(unsigned int cpu)
{
unsigned long timeout;
timeout = jiffies + (10 * HZ);
while (readl(sram_base + MESON_SMP_SRAM_CPU_CTRL_ADDR_REG(cpu))) {
if (!time_before(jiffies, timeout)) {
pr_err("Timeout while waiting for CPU%d status\n",
cpu);
return -ETIMEDOUT;
}
}
writel(__pa_symbol(secondary_startup),
sram_base + MESON_SMP_SRAM_CPU_CTRL_ADDR_REG(cpu));
meson_smp_set_cpu_ctrl(cpu, true);
return 0;
}
static int meson8_smp_boot_secondary(unsigned int cpu,
struct task_struct *idle)
{
struct reset_control *rstc;
int ret;
rstc = meson_smp_get_core_reset(cpu);
if (IS_ERR(rstc)) {
pr_err("Couldn't get the reset controller for CPU%d\n", cpu);
return PTR_ERR(rstc);
}
meson_smp_begin_secondary_boot(cpu);
/* Reset enable */
ret = reset_control_assert(rstc);
if (ret) {
pr_err("Failed to assert CPU%d reset\n", cpu);
goto out;
}
/* CPU power ON */
ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL1,
MESON_CPU_PWR_A9_CNTL1_M(cpu), 0);
if (ret < 0) {
pr_err("Couldn't wake up CPU%d\n", cpu);
goto out;
}
udelay(10);
/* Isolation disable */
ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL0, BIT(cpu),
0);
if (ret < 0) {
pr_err("Error when disabling isolation of CPU%d\n", cpu);
goto out;
}
/* Reset disable */
ret = reset_control_deassert(rstc);
if (ret) {
pr_err("Failed to de-assert CPU%d reset\n", cpu);
goto out;
}
ret = meson_smp_finalize_secondary_boot(cpu);
if (ret)
goto out;
out:
reset_control_put(rstc);
return 0;
}
static int meson8b_smp_boot_secondary(unsigned int cpu,
struct task_struct *idle)
{
struct reset_control *rstc;
int ret;
u32 val;
rstc = meson_smp_get_core_reset(cpu);
if (IS_ERR(rstc)) {
pr_err("Couldn't get the reset controller for CPU%d\n", cpu);
return PTR_ERR(rstc);
}
meson_smp_begin_secondary_boot(cpu);
/* CPU power UP */
ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL0,
MESON_CPU_PWR_A9_CNTL0_M(cpu), 0);
if (ret < 0) {
pr_err("Couldn't power up CPU%d\n", cpu);
goto out;
}
udelay(5);
/* Reset enable */
ret = reset_control_assert(rstc);
if (ret) {
pr_err("Failed to assert CPU%d reset\n", cpu);
goto out;
}
/* Memory power UP */
ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_MEM_PD0,
MESON_CPU_PWR_A9_MEM_PD0_M(cpu), 0);
if (ret < 0) {
pr_err("Couldn't power up the memory for CPU%d\n", cpu);
goto out;
}
/* Wake up CPU */
ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL1,
MESON_CPU_PWR_A9_CNTL1_M(cpu), 0);
if (ret < 0) {
pr_err("Couldn't wake up CPU%d\n", cpu);
goto out;
}
udelay(10);
ret = regmap_read_poll_timeout(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL1, val,
val & MESON_CPU_PWR_A9_CNTL1_ST(cpu),
10, 10000);
if (ret) {
pr_err("Timeout while polling PMU for CPU%d status\n", cpu);
goto out;
}
/* Isolation disable */
ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL0, BIT(cpu),
0);
if (ret < 0) {
pr_err("Error when disabling isolation of CPU%d\n", cpu);
goto out;
}
/* Reset disable */
ret = reset_control_deassert(rstc);
if (ret) {
pr_err("Failed to de-assert CPU%d reset\n", cpu);
goto out;
}
ret = meson_smp_finalize_secondary_boot(cpu);
if (ret)
goto out;
out:
reset_control_put(rstc);
return 0;
}
#ifdef CONFIG_HOTPLUG_CPU
static void meson8_smp_cpu_die(unsigned int cpu)
{
meson_smp_set_cpu_ctrl(cpu, false);
v7_exit_coherency_flush(louis);
scu_power_mode(scu_base, SCU_PM_POWEROFF);
dsb();
wfi();
/* we should never get here */
WARN_ON(1);
}
static int meson8_smp_cpu_kill(unsigned int cpu)
{
int ret, power_mode;
unsigned long timeout;
timeout = jiffies + (50 * HZ);
do {
power_mode = scu_get_cpu_power_mode(scu_base, cpu);
if (power_mode == SCU_PM_POWEROFF)
break;
usleep_range(10000, 15000);
} while (time_before(jiffies, timeout));
if (power_mode != SCU_PM_POWEROFF) {
pr_err("Error while waiting for SCU power-off on CPU%d\n",
cpu);
return -ETIMEDOUT;
}
msleep(30);
/* Isolation enable */
ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL0, BIT(cpu),
0x3);
if (ret < 0) {
pr_err("Error when enabling isolation for CPU%d\n", cpu);
return ret;
}
udelay(10);
/* CPU power OFF */
ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL1,
MESON_CPU_PWR_A9_CNTL1_M(cpu), 0x3);
if (ret < 0) {
pr_err("Couldn't change sleep status of CPU%d\n", cpu);
return ret;
}
return 1;
}
static int meson8b_smp_cpu_kill(unsigned int cpu)
{
int ret, power_mode, count = 5000;
do {
power_mode = scu_get_cpu_power_mode(scu_base, cpu);
if (power_mode == SCU_PM_POWEROFF)
break;
udelay(10);
} while (++count);
if (power_mode != SCU_PM_POWEROFF) {
pr_err("Error while waiting for SCU power-off on CPU%d\n",
cpu);
return -ETIMEDOUT;
}
udelay(10);
/* CPU power DOWN */
ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL0,
MESON_CPU_PWR_A9_CNTL0_M(cpu), 0x3);
if (ret < 0) {
pr_err("Couldn't power down CPU%d\n", cpu);
return ret;
}
/* Isolation enable */
ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL0, BIT(cpu),
0x3);
if (ret < 0) {
pr_err("Error when enabling isolation for CPU%d\n", cpu);
return ret;
}
udelay(10);
/* Sleep status */
ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_CNTL1,
MESON_CPU_PWR_A9_CNTL1_M(cpu), 0x3);
if (ret < 0) {
pr_err("Couldn't change sleep status of CPU%d\n", cpu);
return ret;
}
/* Memory power DOWN */
ret = regmap_update_bits(pmu, MESON_CPU_AO_RTI_PWR_A9_MEM_PD0,
MESON_CPU_PWR_A9_MEM_PD0_M(cpu), 0xf);
if (ret < 0) {
pr_err("Couldn't power down the memory of CPU%d\n", cpu);
return ret;
}
return 1;
}
#endif
static struct smp_operations meson8_smp_ops __initdata = {
.smp_prepare_cpus = meson8_smp_prepare_cpus,
.smp_boot_secondary = meson8_smp_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_die = meson8_smp_cpu_die,
.cpu_kill = meson8_smp_cpu_kill,
#endif
};
static struct smp_operations meson8b_smp_ops __initdata = {
.smp_prepare_cpus = meson8b_smp_prepare_cpus,
.smp_boot_secondary = meson8b_smp_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_die = meson8_smp_cpu_die,
.cpu_kill = meson8b_smp_cpu_kill,
#endif
};
CPU_METHOD_OF_DECLARE(meson8_smp, "amlogic,meson8-smp", &meson8_smp_ops);
CPU_METHOD_OF_DECLARE(meson8b_smp, "amlogic,meson8b-smp", &meson8b_smp_ops);
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