/*
* Copyright (c) 2013-2014 Linaro Ltd.
* Copyright (c) 2013-2014 Hisilicon Limited.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*/
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/memblock.h>
#include <linux/of_address.h>
#include <asm/cputype.h>
#include <asm/cp15.h>
#include <asm/cacheflush.h>
#include <asm/smp.h>
#include <asm/smp_plat.h>
#include "core.h"
/* bits definition in SC_CPU_RESET_REQ[x]/SC_CPU_RESET_DREQ[x]
* 1 -- unreset; 0 -- reset
*/
#define CORE_RESET_BIT(x) (1 << x)
#define NEON_RESET_BIT(x) (1 << (x + 4))
#define CORE_DEBUG_RESET_BIT(x) (1 << (x + 9))
#define CLUSTER_L2_RESET_BIT (1 << 8)
#define CLUSTER_DEBUG_RESET_BIT (1 << 13)
/*
* bits definition in SC_CPU_RESET_STATUS[x]
* 1 -- reset status; 0 -- unreset status
*/
#define CORE_RESET_STATUS(x) (1 << x)
#define NEON_RESET_STATUS(x) (1 << (x + 4))
#define CORE_DEBUG_RESET_STATUS(x) (1 << (x + 9))
#define CLUSTER_L2_RESET_STATUS (1 << 8)
#define CLUSTER_DEBUG_RESET_STATUS (1 << 13)
#define CORE_WFI_STATUS(x) (1 << (x + 16))
#define CORE_WFE_STATUS(x) (1 << (x + 20))
#define CORE_DEBUG_ACK(x) (1 << (x + 24))
#define SC_CPU_RESET_REQ(x) (0x520 + (x << 3)) /* reset */
#define SC_CPU_RESET_DREQ(x) (0x524 + (x << 3)) /* unreset */
#define SC_CPU_RESET_STATUS(x) (0x1520 + (x << 3))
#define FAB_SF_MODE 0x0c
#define FAB_SF_INVLD 0x10
/* bits definition in FB_SF_INVLD */
#define FB_SF_INVLD_START (1 << 8)
#define HIP04_MAX_CLUSTERS 4
#define HIP04_MAX_CPUS_PER_CLUSTER 4
#define POLL_MSEC 10
#define TIMEOUT_MSEC 1000
static void __iomem *sysctrl, *fabric;
static int hip04_cpu_table[HIP04_MAX_CLUSTERS][HIP04_MAX_CPUS_PER_CLUSTER];
static DEFINE_SPINLOCK(boot_lock);
static u32 fabric_phys_addr;
/*
* [0]: bootwrapper physical address
* [1]: bootwrapper size
* [2]: relocation address
* [3]: relocation size
*/
static u32 hip04_boot_method[4];
static bool hip04_cluster_is_down(unsigned int cluster)
{
int i;
for (i = 0; i < HIP04_MAX_CPUS_PER_CLUSTER; i++)
if (hip04_cpu_table[cluster][i])
return false;
return true;
}
static void hip04_set_snoop_filter(unsigned int cluster, unsigned int on)
{
unsigned long data;
if (!fabric)
BUG();
data = readl_relaxed(fabric + FAB_SF_MODE);
if (on)
data |= 1 << cluster;
else
data &= ~(1 << cluster);
writel_relaxed(data, fabric + FAB_SF_MODE);
do {
cpu_relax();
} while (data != readl_relaxed(fabric + FAB_SF_MODE));
}
static int hip04_boot_secondary(unsigned int l_cpu, struct task_struct *idle)
{
unsigned int mpidr, cpu, cluster;
unsigned long data;
void __iomem *sys_dreq, *sys_status;
mpidr = cpu_logical_map(l_cpu);
cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
if (!sysctrl)
return -ENODEV;
if (cluster >= HIP04_MAX_CLUSTERS || cpu >= HIP04_MAX_CPUS_PER_CLUSTER)
return -EINVAL;
spin_lock_irq(&boot_lock);
if (hip04_cpu_table[cluster][cpu])
goto out;
sys_dreq = sysctrl + SC_CPU_RESET_DREQ(cluster);
sys_status = sysctrl + SC_CPU_RESET_STATUS(cluster);
if (hip04_cluster_is_down(cluster)) {
data = CLUSTER_DEBUG_RESET_BIT;
writel_relaxed(data, sys_dreq);
do {
cpu_relax();
data = readl_relaxed(sys_status);
} while (data & CLUSTER_DEBUG_RESET_STATUS);
hip04_set_snoop_filter(cluster, 1);
}
data = CORE_RESET_BIT(cpu) | NEON_RESET_BIT(cpu) | \
CORE_DEBUG_RESET_BIT(cpu);
writel_relaxed(data, sys_dreq);
do {
cpu_relax();
} while (data == readl_relaxed(sys_status));
/*
* We may fail to power up core again without this delay.
* It's not mentioned in document. It's found by test.
*/
udelay(20);
arch_send_wakeup_ipi_mask(cpumask_of(l_cpu));
out:
hip04_cpu_table[cluster][cpu]++;
spin_unlock_irq(&boot_lock);
return 0;
}
#ifdef CONFIG_HOTPLUG_CPU
static void hip04_cpu_die(unsigned int l_cpu)
{
unsigned int mpidr, cpu, cluster;
bool last_man;
mpidr = cpu_logical_map(l_cpu);
cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
spin_lock(&boot_lock);
hip04_cpu_table[cluster][cpu]--;
if (hip04_cpu_table[cluster][cpu] == 1) {
/* A power_up request went ahead of us. */
spin_unlock(&boot_lock);
return;
} else if (hip04_cpu_table[cluster][cpu] > 1) {
pr_err("Cluster %d CPU%d boots multiple times\n", cluster, cpu);
BUG();
}
last_man = hip04_cluster_is_down(cluster);
spin_unlock(&boot_lock);
if (last_man) {
/* Since it's Cortex A15, disable L2 prefetching. */
asm volatile(
"mcr p15, 1, %0, c15, c0, 3 \n\t"
"isb \n\t"
"dsb "
: : "r" (0x400) );
v7_exit_coherency_flush(all);
} else {
v7_exit_coherency_flush(louis);
}
for (;;)
wfi();
}
static int hip04_cpu_kill(unsigned int l_cpu)
{
unsigned int mpidr, cpu, cluster;
unsigned int data, tries, count;
mpidr = cpu_logical_map(l_cpu);
cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
BUG_ON(cluster >= HIP04_MAX_CLUSTERS ||
cpu >= HIP04_MAX_CPUS_PER_CLUSTER);
count = TIMEOUT_MSEC / POLL_MSEC;
spin_lock_irq(&boot_lock);
for (tries = 0; tries < count; tries++) {
if (hip04_cpu_table[cluster][cpu])
goto err;
cpu_relax();
data = readl_relaxed(sysctrl + SC_CPU_RESET_STATUS(cluster));
if (data & CORE_WFI_STATUS(cpu))
break;
spin_unlock_irq(&boot_lock);
/* Wait for clean L2 when the whole cluster is down. */
msleep(POLL_MSEC);
spin_lock_irq(&boot_lock);
}
if (tries >= count)
goto err;
data = CORE_RESET_BIT(cpu) | NEON_RESET_BIT(cpu) | \
CORE_DEBUG_RESET_BIT(cpu);
writel_relaxed(data, sysctrl + SC_CPU_RESET_REQ(cluster));
for (tries = 0; tries < count; tries++) {
cpu_relax();
data = readl_relaxed(sysctrl + SC_CPU_RESET_STATUS(cluster));
if (data & CORE_RESET_STATUS(cpu))
break;
}
if (tries >= count)
goto err;
if (hip04_cluster_is_down(cluster))
hip04_set_snoop_filter(cluster, 0);
spin_unlock_irq(&boot_lock);
return 1;
err:
spin_unlock_irq(&boot_lock);
return 0;
}
#endif
static const struct smp_operations hip04_smp_ops __initconst = {
.smp_boot_secondary = hip04_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_die = hip04_cpu_die,
.cpu_kill = hip04_cpu_kill,
#endif
};
static bool __init hip04_cpu_table_init(void)
{
unsigned int mpidr, cpu, cluster;
mpidr = read_cpuid_mpidr();
cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
if (cluster >= HIP04_MAX_CLUSTERS ||
cpu >= HIP04_MAX_CPUS_PER_CLUSTER) {
pr_err("%s: boot CPU is out of bound!\n", __func__);
return false;
}
hip04_set_snoop_filter(cluster, 1);
hip04_cpu_table[cluster][cpu] = 1;
return true;
}
static int __init hip04_smp_init(void)
{
struct device_node *np, *np_sctl, *np_fab;
struct resource fab_res;
void __iomem *relocation;
int ret = -ENODEV;
np = of_find_compatible_node(NULL, NULL, "hisilicon,hip04-bootwrapper");
if (!np)
goto err;
ret = of_property_read_u32_array(np, "boot-method",
&hip04_boot_method[0], 4);
if (ret)
goto err;
np_sctl = of_find_compatible_node(NULL, NULL, "hisilicon,sysctrl");
if (!np_sctl)
goto err;
np_fab = of_find_compatible_node(NULL, NULL, "hisilicon,hip04-fabric");
if (!np_fab)
goto err;
ret = memblock_reserve(hip04_boot_method[0], hip04_boot_method[1]);
if (ret)
goto err;
relocation = ioremap(hip04_boot_method[2], hip04_boot_method[3]);
if (!relocation) {
pr_err("failed to map relocation space\n");
ret = -ENOMEM;
goto err_reloc;
}
sysctrl = of_iomap(np_sctl, 0);
if (!sysctrl) {
pr_err("failed to get sysctrl base\n");
ret = -ENOMEM;
goto err_sysctrl;
}
ret = of_address_to_resource(np_fab, 0, &fab_res);
if (ret) {
pr_err("failed to get fabric base phys\n");
goto err_fabric;
}
fabric_phys_addr = fab_res.start;
sync_cache_w(&fabric_phys_addr);
fabric = of_iomap(np_fab, 0);
if (!fabric) {
pr_err("failed to get fabric base\n");
ret = -ENOMEM;
goto err_fabric;
}
if (!hip04_cpu_table_init()) {
ret = -EINVAL;
goto err_table;
}
/*
* Fill the instruction address that is used after secondary core
* out of reset.
*/
writel_relaxed(hip04_boot_method[0], relocation);
writel_relaxed(0xa5a5a5a5, relocation + 4); /* magic number */
writel_relaxed(virt_to_phys(secondary_startup), relocation + 8);
writel_relaxed(0, relocation + 12);
iounmap(relocation);
smp_set_ops(&hip04_smp_ops);
return ret;
err_table:
iounmap(fabric);
err_fabric:
iounmap(sysctrl);
err_sysctrl:
iounmap(relocation);
err_reloc:
memblock_free(hip04_boot_method[0], hip04_boot_method[1]);
err:
return ret;
}
early_initcall(hip04_smp_init);