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ARM: vexpress: migrate TC2 to the new MCPM backend abstraction

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Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
This commit is contained in:
Nicolas Pitre 2015-03-14 17:58:33 -04:00 committed by Olof Johansson
parent d3a875444a
commit 41f26e2d94
1 changed files with 84 additions and 213 deletions
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297
arch/arm/mach-vexpress/tc2_pm.c
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@ -18,7 +18,6 @@
#include <linux/kernel.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/irqchip/arm-gic.h>
@ -44,101 +43,36 @@
static void __iomem *scc;
/*
* 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 tc2_pm_lock = __ARCH_SPIN_LOCK_UNLOCKED;
#define TC2_CLUSTERS 2
#define TC2_MAX_CPUS_PER_CLUSTER 3
static unsigned int tc2_nr_cpus[TC2_CLUSTERS];
/* Keep per-cpu usage count to cope with unordered up/down requests */
static int tc2_pm_use_count[TC2_MAX_CPUS_PER_CLUSTER][TC2_CLUSTERS];
#define tc2_cluster_unused(cluster) \
(!tc2_pm_use_count[0][cluster] && \
!tc2_pm_use_count[1][cluster] && \
!tc2_pm_use_count[2][cluster])
static int tc2_pm_power_up(unsigned int cpu, unsigned int cluster)
static int tc2_pm_cpu_powerup(unsigned int cpu, unsigned int cluster)
{
pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
if (cluster >= TC2_CLUSTERS || cpu >= tc2_nr_cpus[cluster])
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(&tc2_pm_lock);
if (tc2_cluster_unused(cluster))
ve_spc_powerdown(cluster, false);
tc2_pm_use_count[cpu][cluster]++;
if (tc2_pm_use_count[cpu][cluster] == 1) {
ve_spc_set_resume_addr(cluster, cpu,
virt_to_phys(mcpm_entry_point));
ve_spc_cpu_wakeup_irq(cluster, cpu, true);
} else if (tc2_pm_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(&tc2_pm_lock);
local_irq_enable();
ve_spc_set_resume_addr(cluster, cpu,
virt_to_phys(mcpm_entry_point));
ve_spc_cpu_wakeup_irq(cluster, cpu, true);
return 0;
}
static void tc2_pm_down(u64 residency)
static int tc2_pm_cluster_powerup(unsigned int cluster)
{
unsigned int mpidr, cpu, cluster;
bool last_man = false, skip_wfi = false;
mpidr = read_cpuid_mpidr();
cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
pr_debug("%s: cluster %u\n", __func__, cluster);
if (cluster >= TC2_CLUSTERS)
return -EINVAL;
ve_spc_powerdown(cluster, false);
return 0;
}
static void tc2_pm_cpu_powerdown_prepare(unsigned int cpu, unsigned int cluster)
{
pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
BUG_ON(cluster >= TC2_CLUSTERS || cpu >= TC2_MAX_CPUS_PER_CLUSTER);
__mcpm_cpu_going_down(cpu, cluster);
arch_spin_lock(&tc2_pm_lock);
BUG_ON(__mcpm_cluster_state(cluster) != CLUSTER_UP);
tc2_pm_use_count[cpu][cluster]--;
if (tc2_pm_use_count[cpu][cluster] == 0) {
ve_spc_cpu_wakeup_irq(cluster, cpu, true);
if (tc2_cluster_unused(cluster)) {
ve_spc_powerdown(cluster, true);
ve_spc_global_wakeup_irq(true);
last_man = true;
}
} else if (tc2_pm_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();
ve_spc_cpu_wakeup_irq(cluster, cpu, true);
/*
* If the CPU is committed to power down, make sure
* the power controller will be in charge of waking it
@ -146,55 +80,38 @@ static void tc2_pm_down(u64 residency)
* to the CPU by disabling the GIC CPU IF to prevent wfi
* from completing execution behind power controller back
*/
if (!skip_wfi)
gic_cpu_if_down();
if (last_man && __mcpm_outbound_enter_critical(cpu, cluster)) {
arch_spin_unlock(&tc2_pm_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) );
}
v7_exit_coherency_flush(all);
cci_disable_port_by_cpu(mpidr);
__mcpm_outbound_leave_critical(cluster, CLUSTER_DOWN);
} else {
/*
* If last man then undo any setup done previously.
*/
if (last_man) {
ve_spc_powerdown(cluster, false);
ve_spc_global_wakeup_irq(false);
}
arch_spin_unlock(&tc2_pm_lock);
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. */
gic_cpu_if_down();
}
static void tc2_pm_power_down(void)
static void tc2_pm_cluster_powerdown_prepare(unsigned int cluster)
{
tc2_pm_down(0);
pr_debug("%s: cluster %u\n", __func__, cluster);
BUG_ON(cluster >= TC2_CLUSTERS);
ve_spc_powerdown(cluster, true);
ve_spc_global_wakeup_irq(true);
}
static void tc2_pm_cpu_cache_disable(void)
{
v7_exit_coherency_flush(louis);
}
static void tc2_pm_cluster_cache_disable(void)
{
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) );
}
v7_exit_coherency_flush(all);
cci_disable_port_by_cpu(read_cpuid_mpidr());
}
static int tc2_core_in_reset(unsigned int cpu, unsigned int cluster)
@ -217,27 +134,21 @@ static int tc2_pm_wait_for_powerdown(unsigned int cpu, unsigned int cluster)
BUG_ON(cluster >= TC2_CLUSTERS || cpu >= TC2_MAX_CPUS_PER_CLUSTER);
for (tries = 0; tries < TIMEOUT_MSEC / POLL_MSEC; ++tries) {
/*
* Only examine the hardware state if the target CPU has
* caught up at least as far as tc2_pm_down():
*/
if (ACCESS_ONCE(tc2_pm_use_count[cpu][cluster]) == 0) {
pr_debug("%s(cpu=%u, cluster=%u): RESET_CTRL = 0x%08X\n",
__func__, cpu, cluster,
readl_relaxed(scc + RESET_CTRL));
pr_debug("%s(cpu=%u, cluster=%u): RESET_CTRL = 0x%08X\n",
__func__, cpu, cluster,
readl_relaxed(scc + RESET_CTRL));
/*
* We need the CPU to reach WFI, but the power
* controller may put the cluster in reset and
* power it off as soon as that happens, before
* we have a chance to see STANDBYWFI.
*
* So we need to check for both conditions:
*/
if (tc2_core_in_reset(cpu, cluster) ||
ve_spc_cpu_in_wfi(cpu, cluster))
return 0; /* success: the CPU is halted */
}
/*
* We need the CPU to reach WFI, but the power
* controller may put the cluster in reset and
* power it off as soon as that happens, before
* we have a chance to see STANDBYWFI.
*
* So we need to check for both conditions:
*/
if (tc2_core_in_reset(cpu, cluster) ||
ve_spc_cpu_in_wfi(cpu, cluster))
return 0; /* success: the CPU is halted */
/* Otherwise, wait and retry: */
msleep(POLL_MSEC);
@ -246,72 +157,40 @@ static int tc2_pm_wait_for_powerdown(unsigned int cpu, unsigned int cluster)
return -ETIMEDOUT; /* timeout */
}
static void tc2_pm_suspend(u64 residency)
static void tc2_pm_cpu_suspend_prepare(unsigned int cpu, unsigned int cluster)
{
unsigned int mpidr, cpu, cluster;
mpidr = read_cpuid_mpidr();
cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
ve_spc_set_resume_addr(cluster, cpu, virt_to_phys(mcpm_entry_point));
tc2_pm_down(residency);
}
static void tc2_pm_powered_up(void)
static void tc2_pm_cpu_is_up(unsigned int cpu, unsigned int cluster)
{
unsigned int mpidr, cpu, cluster;
unsigned long flags;
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(cluster >= TC2_CLUSTERS || cpu >= TC2_MAX_CPUS_PER_CLUSTER);
local_irq_save(flags);
arch_spin_lock(&tc2_pm_lock);
if (tc2_cluster_unused(cluster)) {
ve_spc_powerdown(cluster, false);
ve_spc_global_wakeup_irq(false);
}
if (!tc2_pm_use_count[cpu][cluster])
tc2_pm_use_count[cpu][cluster] = 1;
ve_spc_cpu_wakeup_irq(cluster, cpu, false);
ve_spc_set_resume_addr(cluster, cpu, 0);
}
arch_spin_unlock(&tc2_pm_lock);
local_irq_restore(flags);
static void tc2_pm_cluster_is_up(unsigned int cluster)
{
pr_debug("%s: cluster %u\n", __func__, cluster);
BUG_ON(cluster >= TC2_CLUSTERS);
ve_spc_powerdown(cluster, false);
ve_spc_global_wakeup_irq(false);
}
static const struct mcpm_platform_ops tc2_pm_power_ops = {
.power_up = tc2_pm_power_up,
.power_down = tc2_pm_power_down,
.cpu_powerup = tc2_pm_cpu_powerup,
.cluster_powerup = tc2_pm_cluster_powerup,
.cpu_suspend_prepare = tc2_pm_cpu_suspend_prepare,
.cpu_powerdown_prepare = tc2_pm_cpu_powerdown_prepare,
.cluster_powerdown_prepare = tc2_pm_cluster_powerdown_prepare,
.cpu_cache_disable = tc2_pm_cpu_cache_disable,
.cluster_cache_disable = tc2_pm_cluster_cache_disable,
.wait_for_powerdown = tc2_pm_wait_for_powerdown,
.suspend = tc2_pm_suspend,
.powered_up = tc2_pm_powered_up,
.cpu_is_up = tc2_pm_cpu_is_up,
.cluster_is_up = tc2_pm_cluster_is_up,
};
static bool __init tc2_pm_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);
if (cluster >= TC2_CLUSTERS || cpu >= tc2_nr_cpus[cluster]) {
pr_err("%s: boot CPU is out of bound!\n", __func__);
return false;
}
tc2_pm_use_count[cpu][cluster] = 1;
return true;
}
/*
* Enable cluster-level coherency, in preparation for turning on the MMU.
*/
@ -323,23 +202,9 @@ static void __naked tc2_pm_power_up_setup(unsigned int affinity_level)
" b cci_enable_port_for_self ");
}
static void __init tc2_cache_off(void)
{
pr_info("TC2: disabling cache during MCPM loopback test\n");
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) );
}
v7_exit_coherency_flush(all);
cci_disable_port_by_cpu(read_cpuid_mpidr());
}
static int __init tc2_pm_init(void)
{
unsigned int mpidr, cpu, cluster;
int ret, irq;
u32 a15_cluster_id, a7_cluster_id, sys_info;
struct device_node *np;
@ -379,14 +244,20 @@ static int __init tc2_pm_init(void)
if (!cci_probed())
return -ENODEV;
if (!tc2_pm_usage_count_init())
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);
if (cluster >= TC2_CLUSTERS || cpu >= tc2_nr_cpus[cluster]) {
pr_err("%s: boot CPU is out of bound!\n", __func__);
return -EINVAL;
}
ret = mcpm_platform_register(&tc2_pm_power_ops);
if (!ret) {
mcpm_sync_init(tc2_pm_power_up_setup);
/* test if we can (re)enable the CCI on our own */
BUG_ON(mcpm_loopback(tc2_cache_off) != 0);
BUG_ON(mcpm_loopback(tc2_pm_cluster_cache_disable) != 0);
pr_info("TC2 power management initialized\n");
}
return ret;