404 lines
11 KiB
C
404 lines
11 KiB
C
/*
|
|
* Copyright (c) 2014 Samsung Electronics Co., Ltd.
|
|
* http://www.samsung.com
|
|
*
|
|
* arch/arm/mach-exynos/mcpm-exynos.c
|
|
*
|
|
* Based on arch/arm/mach-vexpress/dcscb.c
|
|
*
|
|
* 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/arm-cci.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/io.h>
|
|
#include <linux/of_address.h>
|
|
|
|
#include <asm/cputype.h>
|
|
#include <asm/cp15.h>
|
|
#include <asm/mcpm.h>
|
|
|
|
#include "regs-pmu.h"
|
|
#include "common.h"
|
|
|
|
#define EXYNOS5420_CPUS_PER_CLUSTER 4
|
|
#define EXYNOS5420_NR_CLUSTERS 2
|
|
|
|
#define EXYNOS5420_ENABLE_AUTOMATIC_CORE_DOWN BIT(9)
|
|
#define EXYNOS5420_USE_ARM_CORE_DOWN_STATE BIT(29)
|
|
#define EXYNOS5420_USE_L2_COMMON_UP_STATE BIT(30)
|
|
|
|
/*
|
|
* The common v7_exit_coherency_flush API could not be used because of the
|
|
* Erratum 799270 workaround. This macro is the same as the common one (in
|
|
* arch/arm/include/asm/cacheflush.h) except for the erratum handling.
|
|
*/
|
|
#define exynos_v7_exit_coherency_flush(level) \
|
|
asm volatile( \
|
|
"stmfd sp!, {fp, ip}\n\t"\
|
|
"mrc p15, 0, r0, c1, c0, 0 @ get SCTLR\n\t" \
|
|
"bic r0, r0, #"__stringify(CR_C)"\n\t" \
|
|
"mcr p15, 0, r0, c1, c0, 0 @ set SCTLR\n\t" \
|
|
"isb\n\t"\
|
|
"bl v7_flush_dcache_"__stringify(level)"\n\t" \
|
|
"mrc p15, 0, r0, c1, c0, 1 @ get ACTLR\n\t" \
|
|
"bic r0, r0, #(1 << 6) @ disable local coherency\n\t" \
|
|
/* Dummy Load of a device register to avoid Erratum 799270 */ \
|
|
"ldr r4, [%0]\n\t" \
|
|
"and r4, r4, #0\n\t" \
|
|
"orr r0, r0, r4\n\t" \
|
|
"mcr p15, 0, r0, c1, c0, 1 @ set ACTLR\n\t" \
|
|
"isb\n\t" \
|
|
"dsb\n\t" \
|
|
"ldmfd sp!, {fp, ip}" \
|
|
: \
|
|
: "Ir" (pmu_base_addr + S5P_INFORM0) \
|
|
: "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", \
|
|
"r9", "r10", "lr", "memory")
|
|
|
|
/*
|
|
* We can't use regular spinlocks. In the switcher case, it is possible
|
|
* for an outbound CPU to call power_down() after its inbound counterpart
|
|
* is already live using the same logical CPU number which trips lockdep
|
|
* debugging.
|
|
*/
|
|
static arch_spinlock_t exynos_mcpm_lock = __ARCH_SPIN_LOCK_UNLOCKED;
|
|
static int
|
|
cpu_use_count[EXYNOS5420_CPUS_PER_CLUSTER][EXYNOS5420_NR_CLUSTERS];
|
|
|
|
#define exynos_cluster_usecnt(cluster) \
|
|
(cpu_use_count[0][cluster] + \
|
|
cpu_use_count[1][cluster] + \
|
|
cpu_use_count[2][cluster] + \
|
|
cpu_use_count[3][cluster])
|
|
|
|
#define exynos_cluster_unused(cluster) !exynos_cluster_usecnt(cluster)
|
|
|
|
static int exynos_power_up(unsigned int cpu, unsigned int cluster)
|
|
{
|
|
unsigned int cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER);
|
|
|
|
pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
|
|
if (cpu >= EXYNOS5420_CPUS_PER_CLUSTER ||
|
|
cluster >= EXYNOS5420_NR_CLUSTERS)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* Since this is called with IRQs enabled, and no arch_spin_lock_irq
|
|
* variant exists, we need to disable IRQs manually here.
|
|
*/
|
|
local_irq_disable();
|
|
arch_spin_lock(&exynos_mcpm_lock);
|
|
|
|
cpu_use_count[cpu][cluster]++;
|
|
if (cpu_use_count[cpu][cluster] == 1) {
|
|
bool was_cluster_down =
|
|
(exynos_cluster_usecnt(cluster) == 1);
|
|
|
|
/*
|
|
* Turn on the cluster (L2/COMMON) and then power on the
|
|
* cores.
|
|
*/
|
|
if (was_cluster_down)
|
|
exynos_cluster_power_up(cluster);
|
|
|
|
exynos_cpu_power_up(cpunr);
|
|
} else if (cpu_use_count[cpu][cluster] != 2) {
|
|
/*
|
|
* The only possible values are:
|
|
* 0 = CPU down
|
|
* 1 = CPU (still) up
|
|
* 2 = CPU requested to be up before it had a chance
|
|
* to actually make itself down.
|
|
* Any other value is a bug.
|
|
*/
|
|
BUG();
|
|
}
|
|
|
|
arch_spin_unlock(&exynos_mcpm_lock);
|
|
local_irq_enable();
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* NOTE: This function requires the stack data to be visible through power down
|
|
* and can only be executed on processors like A15 and A7 that hit the cache
|
|
* with the C bit clear in the SCTLR register.
|
|
*/
|
|
static void exynos_power_down(void)
|
|
{
|
|
unsigned int mpidr, cpu, cluster;
|
|
bool last_man = false, skip_wfi = false;
|
|
unsigned int cpunr;
|
|
|
|
mpidr = read_cpuid_mpidr();
|
|
cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
|
|
cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
|
|
cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER);
|
|
|
|
pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
|
|
BUG_ON(cpu >= EXYNOS5420_CPUS_PER_CLUSTER ||
|
|
cluster >= EXYNOS5420_NR_CLUSTERS);
|
|
|
|
__mcpm_cpu_going_down(cpu, cluster);
|
|
|
|
arch_spin_lock(&exynos_mcpm_lock);
|
|
BUG_ON(__mcpm_cluster_state(cluster) != CLUSTER_UP);
|
|
cpu_use_count[cpu][cluster]--;
|
|
if (cpu_use_count[cpu][cluster] == 0) {
|
|
exynos_cpu_power_down(cpunr);
|
|
|
|
if (exynos_cluster_unused(cluster)) {
|
|
exynos_cluster_power_down(cluster);
|
|
last_man = true;
|
|
}
|
|
} else if (cpu_use_count[cpu][cluster] == 1) {
|
|
/*
|
|
* A power_up request went ahead of us.
|
|
* Even if we do not want to shut this CPU down,
|
|
* the caller expects a certain state as if the WFI
|
|
* was aborted. So let's continue with cache cleaning.
|
|
*/
|
|
skip_wfi = true;
|
|
} else {
|
|
BUG();
|
|
}
|
|
|
|
if (last_man && __mcpm_outbound_enter_critical(cpu, cluster)) {
|
|
arch_spin_unlock(&exynos_mcpm_lock);
|
|
|
|
if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A15) {
|
|
/*
|
|
* On the Cortex-A15 we need to disable
|
|
* L2 prefetching before flushing the cache.
|
|
*/
|
|
asm volatile(
|
|
"mcr p15, 1, %0, c15, c0, 3\n\t"
|
|
"isb\n\t"
|
|
"dsb"
|
|
: : "r" (0x400));
|
|
}
|
|
|
|
/* Flush all cache levels for this cluster. */
|
|
exynos_v7_exit_coherency_flush(all);
|
|
|
|
/*
|
|
* Disable cluster-level coherency by masking
|
|
* incoming snoops and DVM messages:
|
|
*/
|
|
cci_disable_port_by_cpu(mpidr);
|
|
|
|
__mcpm_outbound_leave_critical(cluster, CLUSTER_DOWN);
|
|
} else {
|
|
arch_spin_unlock(&exynos_mcpm_lock);
|
|
|
|
/* Disable and flush the local CPU cache. */
|
|
exynos_v7_exit_coherency_flush(louis);
|
|
}
|
|
|
|
__mcpm_cpu_down(cpu, cluster);
|
|
|
|
/* Now we are prepared for power-down, do it: */
|
|
if (!skip_wfi)
|
|
wfi();
|
|
|
|
/* Not dead at this point? Let our caller cope. */
|
|
}
|
|
|
|
static int exynos_wait_for_powerdown(unsigned int cpu, unsigned int cluster)
|
|
{
|
|
unsigned int tries = 100;
|
|
unsigned int cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER);
|
|
|
|
pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
|
|
BUG_ON(cpu >= EXYNOS5420_CPUS_PER_CLUSTER ||
|
|
cluster >= EXYNOS5420_NR_CLUSTERS);
|
|
|
|
/* Wait for the core state to be OFF */
|
|
while (tries--) {
|
|
if (ACCESS_ONCE(cpu_use_count[cpu][cluster]) == 0) {
|
|
if ((exynos_cpu_power_state(cpunr) == 0))
|
|
return 0; /* success: the CPU is halted */
|
|
}
|
|
|
|
/* Otherwise, wait and retry: */
|
|
msleep(1);
|
|
}
|
|
|
|
return -ETIMEDOUT; /* timeout */
|
|
}
|
|
|
|
static void exynos_powered_up(void)
|
|
{
|
|
unsigned int mpidr, cpu, cluster;
|
|
|
|
mpidr = read_cpuid_mpidr();
|
|
cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
|
|
cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
|
|
|
|
arch_spin_lock(&exynos_mcpm_lock);
|
|
if (cpu_use_count[cpu][cluster] == 0)
|
|
cpu_use_count[cpu][cluster] = 1;
|
|
arch_spin_unlock(&exynos_mcpm_lock);
|
|
}
|
|
|
|
static void exynos_suspend(u64 residency)
|
|
{
|
|
unsigned int mpidr, cpunr;
|
|
|
|
exynos_power_down();
|
|
|
|
/*
|
|
* Execution reaches here only if cpu did not power down.
|
|
* Hence roll back the changes done in exynos_power_down function.
|
|
*
|
|
* CAUTION: "This function requires the stack data to be visible through
|
|
* power down and can only be executed on processors like A15 and A7
|
|
* that hit the cache with the C bit clear in the SCTLR register."
|
|
*/
|
|
mpidr = read_cpuid_mpidr();
|
|
cpunr = exynos_pmu_cpunr(mpidr);
|
|
|
|
exynos_cpu_power_up(cpunr);
|
|
}
|
|
|
|
static const struct mcpm_platform_ops exynos_power_ops = {
|
|
.power_up = exynos_power_up,
|
|
.power_down = exynos_power_down,
|
|
.wait_for_powerdown = exynos_wait_for_powerdown,
|
|
.suspend = exynos_suspend,
|
|
.powered_up = exynos_powered_up,
|
|
};
|
|
|
|
static void __init exynos_mcpm_usage_count_init(void)
|
|
{
|
|
unsigned int mpidr, cpu, cluster;
|
|
|
|
mpidr = read_cpuid_mpidr();
|
|
cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
|
|
cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
|
|
|
|
pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
|
|
BUG_ON(cpu >= EXYNOS5420_CPUS_PER_CLUSTER ||
|
|
cluster >= EXYNOS5420_NR_CLUSTERS);
|
|
|
|
cpu_use_count[cpu][cluster] = 1;
|
|
}
|
|
|
|
/*
|
|
* Enable cluster-level coherency, in preparation for turning on the MMU.
|
|
*/
|
|
static void __naked exynos_pm_power_up_setup(unsigned int affinity_level)
|
|
{
|
|
asm volatile ("\n"
|
|
"cmp r0, #1\n"
|
|
"bxne lr\n"
|
|
"b cci_enable_port_for_self");
|
|
}
|
|
|
|
static void __init exynos_cache_off(void)
|
|
{
|
|
if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A15) {
|
|
/* disable L2 prefetching on the Cortex-A15 */
|
|
asm volatile(
|
|
"mcr p15, 1, %0, c15, c0, 3\n\t"
|
|
"isb\n\t"
|
|
"dsb"
|
|
: : "r" (0x400));
|
|
}
|
|
exynos_v7_exit_coherency_flush(all);
|
|
}
|
|
|
|
static const struct of_device_id exynos_dt_mcpm_match[] = {
|
|
{ .compatible = "samsung,exynos5420" },
|
|
{ .compatible = "samsung,exynos5800" },
|
|
{},
|
|
};
|
|
|
|
static int __init exynos_mcpm_init(void)
|
|
{
|
|
struct device_node *node;
|
|
void __iomem *ns_sram_base_addr;
|
|
unsigned int value, i;
|
|
int ret;
|
|
|
|
node = of_find_matching_node(NULL, exynos_dt_mcpm_match);
|
|
if (!node)
|
|
return -ENODEV;
|
|
of_node_put(node);
|
|
|
|
if (!cci_probed())
|
|
return -ENODEV;
|
|
|
|
node = of_find_compatible_node(NULL, NULL,
|
|
"samsung,exynos4210-sysram-ns");
|
|
if (!node)
|
|
return -ENODEV;
|
|
|
|
ns_sram_base_addr = of_iomap(node, 0);
|
|
of_node_put(node);
|
|
if (!ns_sram_base_addr) {
|
|
pr_err("failed to map non-secure iRAM base address\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/*
|
|
* To increase the stability of KFC reset we need to program
|
|
* the PMU SPARE3 register
|
|
*/
|
|
pmu_raw_writel(EXYNOS5420_SWRESET_KFC_SEL, S5P_PMU_SPARE3);
|
|
|
|
exynos_mcpm_usage_count_init();
|
|
|
|
ret = mcpm_platform_register(&exynos_power_ops);
|
|
if (!ret)
|
|
ret = mcpm_sync_init(exynos_pm_power_up_setup);
|
|
if (!ret)
|
|
ret = mcpm_loopback(exynos_cache_off); /* turn on the CCI */
|
|
if (ret) {
|
|
iounmap(ns_sram_base_addr);
|
|
return ret;
|
|
}
|
|
|
|
mcpm_smp_set_ops();
|
|
|
|
pr_info("Exynos MCPM support installed\n");
|
|
|
|
/*
|
|
* On Exynos5420/5800 for the A15 and A7 clusters:
|
|
*
|
|
* EXYNOS5420_ENABLE_AUTOMATIC_CORE_DOWN ensures that all the cores
|
|
* in a cluster are turned off before turning off the cluster L2.
|
|
*
|
|
* EXYNOS5420_USE_ARM_CORE_DOWN_STATE ensures that a cores is powered
|
|
* off before waking it up.
|
|
*
|
|
* EXYNOS5420_USE_L2_COMMON_UP_STATE ensures that cluster L2 will be
|
|
* turned on before the first man is powered up.
|
|
*/
|
|
for (i = 0; i < EXYNOS5420_NR_CLUSTERS; i++) {
|
|
value = pmu_raw_readl(EXYNOS_COMMON_OPTION(i));
|
|
value |= EXYNOS5420_ENABLE_AUTOMATIC_CORE_DOWN |
|
|
EXYNOS5420_USE_ARM_CORE_DOWN_STATE |
|
|
EXYNOS5420_USE_L2_COMMON_UP_STATE;
|
|
pmu_raw_writel(value, EXYNOS_COMMON_OPTION(i));
|
|
}
|
|
|
|
/*
|
|
* U-Boot SPL is hardcoded to jump to the start of ns_sram_base_addr
|
|
* as part of secondary_cpu_start(). Let's redirect it to the
|
|
* mcpm_entry_point().
|
|
*/
|
|
__raw_writel(0xe59f0000, ns_sram_base_addr); /* ldr r0, [pc, #0] */
|
|
__raw_writel(0xe12fff10, ns_sram_base_addr + 4); /* bx r0 */
|
|
__raw_writel(virt_to_phys(mcpm_entry_point), ns_sram_base_addr + 8);
|
|
|
|
iounmap(ns_sram_base_addr);
|
|
|
|
return ret;
|
|
}
|
|
|
|
early_initcall(exynos_mcpm_init);
|