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linux-next/arch/arm/mach-exynos/mcpm-exynos.c
Pankaj Dubey 2e94ac4289 ARM: EXYNOS: Refactored code for using PMU address via DT
Under "arm/mach-exynos" many files are using PMU register offsets.
Since we have added support for accessing PMU base address via DT,
now we can remove PMU mapping from exynosX_iodesc. Let's convert
all these access using iomapped address.
This will help us in removing static mapping of PMU base address
as well as help in reducing dependency over machine header files.
Thus helping for migration of PMU implementation from machine to
driver folder which can be reused for ARM64 based SoC.

Also as we have removed static mappings from "regs-pmu.h" it does
not need map.h anymore. But "platsmp.c" needed this and till now it
got included indirectly. So lets move header inclusion of
"mach/map.h" from "regs-pmu.h" to "platsmp.c".

Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2014-07-23 08:20:30 +09:00

391 lines
10 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" \
"clrex\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_number() == 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 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) {
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);