[PATCH 3/6] ARM: EXYNOS: add Exynos Dual Cluster Support

[Vyacheslav Tyrtov <v.tyrtov@samsung.com>]

From: Tarek Dakhran <t.dakhran@samsung.com>

Add EDCS(Exynos Dual Cluster Support) for Samsung Exynos5410 SoC.
This enables all 8 cores, 4 x A7 and 4 x A15 run at the same time.

Signed-off-by: Tarek Dakhran <t.dakhran@samsung.com>
Signed-off-by: Vyacheslav Tyrtov <v.tyrtov@samsung.com>
---
 arch/arm/mach-exynos/Makefile      |   2 +
 arch/arm/mach-exynos/edcs.c        | 217 +++++++++++++++++++++++++++++++++++++
 arch/arm/mach-exynos/edcs.h        |  41 +++++++
 arch/arm/mach-exynos/edcs_status.c | 110 +++++++++++++++++++
 4 files changed, 370 insertions(+)
 create mode 100644 arch/arm/mach-exynos/edcs.c
 create mode 100644 arch/arm/mach-exynos/edcs.h
 create mode 100644 arch/arm/mach-exynos/edcs_status.c

diff --git a/arch/arm/mach-exynos/Makefile b/arch/arm/mach-exynos/Makefile
index 5369615..18e6162 100644
--- a/arch/arm/mach-exynos/Makefile
+++ b/arch/arm/mach-exynos/Makefile
@@ -34,3 +34,5 @@ AFLAGS_exynos-smc.o		:=-Wa,-march=armv7-a$(plus_sec)
 
 obj-$(CONFIG_MACH_EXYNOS4_DT)		+= mach-exynos4-dt.o
 obj-$(CONFIG_MACH_EXYNOS5_DT)		+= mach-exynos5-dt.o
+
+obj-$(CONFIG_ARM_CCI)		+= edcs.o	edcs_status.o
diff --git a/arch/arm/mach-exynos/edcs.c b/arch/arm/mach-exynos/edcs.c
new file mode 100644
index 0000000..34b4e4b
--- /dev/null
+++ b/arch/arm/mach-exynos/edcs.c
@@ -0,0 +1,217 @@
+/*
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ * Author: Tarek Dakhran <t.dakhran@samsung.com>
+ *
+ * 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.
+ *
+ * EDCS(EXYNOS dual cluster support) for Exynos5410 SoC.
+ */
+
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/errno.h>
+#include <linux/vexpress.h>
+#include <asm/mcpm.h>
+#include <asm/proc-fns.h>
+#include <asm/cacheflush.h>
+#include <asm/cputype.h>
+#include <asm/cp15.h>
+
+#include "edcs.h"
+
+static arch_spinlock_t exynos_lock = __ARCH_SPIN_LOCK_UNLOCKED;
+static int kfs_use_count[MAX_CPUS_PER_CLUSTER][MAX_NR_CLUSTERS];
+static int core_count[MAX_NR_CLUSTERS];
+
+static int exynos_core_power_control(unsigned int cpu, unsigned int cluster,
+				int enable)
+{
+	unsigned long timeout = jiffies + msecs_to_jiffies(10);
+	unsigned int offset = cluster * MAX_CPUS_PER_CLUSTER + cpu;
+	int value = enable ? S5P_CORE_LOCAL_PWR_EN : 0;
+
+	if ((__raw_readl(EXYNOS5410_CORE_STATUS(offset)) & 0x3) == value)
+		return 0;
+
+	__raw_writel(value, EXYNOS5410_CORE_CONFIGURATION(offset));
+	do {
+		if ((__raw_readl(EXYNOS5410_CORE_STATUS(offset)) & 0x3)
+				== value)
+			return 0;
+	} while (time_before(jiffies, timeout));
+
+	return -EDEADLK;
+}
+static int exynos_cluster_power_control(unsigned int cluster, int enable)
+{
+	unsigned long timeout = jiffies + msecs_to_jiffies(10);
+	int value = enable ? S5P_CORE_LOCAL_PWR_EN : 0;
+
+	if ((__raw_readl(EXYNOS5410_COMMON_STATUS(cluster)) & 0x3)
+			== value)
+		return 0;
+
+	__raw_writel(value, EXYNOS5410_COMMON_CONFIGURATION(cluster));
+	do {
+		if ((__raw_readl(EXYNOS5410_COMMON_STATUS(cluster)) &
+			__raw_readl(EXYNOS5410_L2_STATUS(cluster)) & 0x3)
+				== value)
+			return 0;
+	} while (time_before(jiffies, timeout));
+
+	return -EDEADLK;
+}
+
+static int exynos_core_power_up(unsigned int cpu, unsigned int cluster)
+{
+	return exynos_core_power_control(cpu, cluster, 1);
+}
+
+static int exynos_core_power_down(unsigned int cpu, unsigned int cluster)
+{
+	return exynos_core_power_control(cpu, cluster, 0);
+}
+
+static int exynos_cluster_power_up(unsigned int cluster)
+{
+	return exynos_cluster_power_control(cluster, 1);
+}
+
+static int exynos_power_up(unsigned int cpu, unsigned int cluster)
+{
+	int ret;
+	local_irq_disable();
+	arch_spin_lock(&exynos_lock);
+
+	pr_info("A%d CORE%d\n", 15 - cluster * 8, cpu);
+	kfs_use_count[cpu][cluster]++;
+	if (kfs_use_count[cpu][cluster] == 1) {
+		++core_count[cluster];
+		if (core_count[cluster] == 1) {
+			ret = exynos_cluster_power_up(cluster);
+			if (ret) {
+				pr_err("%s: cluster %u power up error\n",
+					__func__, cluster);
+				return ret;
+			}
+			__cci_control_port_by_index(MAX_NR_CLUSTERS
+					 - cluster, true);
+		}
+		ret = exynos_core_power_up(cpu, cluster);
+		if (ret) {
+			pr_err("%s: cpu %u cluster %u power up error\n",
+				__func__, cpu, cluster);
+			return ret;
+		}
+	} else if (kfs_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_lock);
+	local_irq_enable();
+	return 0;
+}
+static void exynos_power_down(void)
+{
+	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_info("A%d CORE%d\n", 15 - cluster * 8, cpu);
+	BUG_ON(cpu >= MAX_CPUS_PER_CLUSTER  || cluster >= MAX_NR_CLUSTERS);
+	__mcpm_cpu_going_down(cpu, cluster);
+	arch_spin_lock(&exynos_lock);
+	BUG_ON(__mcpm_cluster_state(cluster) != CLUSTER_UP);
+	kfs_use_count[cpu][cluster]--;
+
+	if (kfs_use_count[cpu][cluster] == 0) {
+		exynos_core_power_down(cpu, cluster);
+		--core_count[cluster];
+		if (core_count[cluster] == 0)
+			last_man = true;
+
+	} else if (kfs_use_count[cpu][cluster] == 1) {
+		skip_wfi = true;
+	} else
+		BUG();
+	if (last_man && __mcpm_outbound_enter_critical(cpu, cluster)) {
+		arch_spin_unlock(&exynos_lock);
+		flush_cache_all();
+		set_cr(get_cr() & ~CR_C);
+		flush_cache_all();
+		outer_flush_all();
+		set_auxcr(get_auxcr() & ~(1 << 6));
+		cci_disable_port_by_cpu(mpidr);
+		__mcpm_outbound_leave_critical(cluster, CLUSTER_DOWN);
+	} else {
+		arch_spin_unlock(&exynos_lock);
+		flush_cache_louis();
+		set_cr(get_cr() & ~CR_C);
+		flush_cache_louis();
+		set_auxcr(get_auxcr() & ~(1 << 6));
+	}
+	__mcpm_cpu_down(cpu, cluster);
+
+	dsb();
+	if (!skip_wfi)
+		wfi();
+}
+static const struct mcpm_platform_ops exynos_power_ops = {
+	.power_up	= exynos_power_up,
+	.power_down	= exynos_power_down,
+};
+
+static void __init edcs_data_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 >= 4 || cluster >= 2);
+	kfs_use_count[cpu][cluster] = 1;
+	++core_count[cluster];
+	__cci_control_port_by_index(MAX_NR_CLUSTERS - cluster, true);
+}
+
+
+static int __init edcs_init(void)
+{
+	struct device_node *node;
+
+	if (!cci_probed())
+		return -ENODEV;
+
+	node = of_find_compatible_node(NULL, NULL, "samsung,edcs");
+	if (!node)
+		return -ENODEV;
+	edcs_data_init();
+	mcpm_smp_set_ops();
+	mcpm_platform_register(&exynos_power_ops);
+
+	/*
+	 * Future entries into the kernel can now go
+	 * through the cluster entry vectors.
+	 */
+
+	__raw_writel(virt_to_phys(mcpm_entry_point),
+			S5P_VA_SYSRAM_NS + 0x1c);
+
+	pr_info("EDCS: EXYNOS5410 DUAL CLUSTER SUPPORT installed\n");
+
+	return 0;
+}
+
+early_initcall(edcs_init);
diff --git a/arch/arm/mach-exynos/edcs.h b/arch/arm/mach-exynos/edcs.h
new file mode 100644
index 0000000..dd3e204
--- /dev/null
+++ b/arch/arm/mach-exynos/edcs.h
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ * Author: Tarek Dakhran <t.dakhran@samsung.com>
+ *
+ * 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.
+ *
+ * EDCS(EXYNOS dual cluster support) for Exynos5410 SoC.
+ */
+
+#include <linux/arm-cci.h>
+#include <linux/of_address.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <mach/regs-pmu.h>
+
+#define EXYNOS5410_ARM_COMMON_CONFIGURATION     S5P_PMUREG(0x2500)
+#define EXYNOS5410_COMMON_CONFIGURATION(_nr)        \
+	(EXYNOS5410_ARM_COMMON_CONFIGURATION + ((_nr) * 0x80))
+#define EXYNOS5410_COMMON_STATUS(_nr)               \
+	(EXYNOS5410_COMMON_CONFIGURATION(_nr) + 0x4)
+#define EXYNOS5410_COMMON_OPTION(_nr)               \
+	(EXYNOS5410_COMMON_CONFIGURATION(_nr) + 0x8)
+
+#define EXYNOS5410_ARM_L2_CONFIGURATION         S5P_PMUREG(0x2600)
+#define EXYNOS5410_L2_CONFIGURATION(_nr)    \
+	(EXYNOS5410_ARM_L2_CONFIGURATION + ((_nr) * 0x80))
+#define EXYNOS5410_L2_STATUS(_nr)           \
+	(EXYNOS5410_L2_CONFIGURATION(_nr) + 0x4)
+#define EXYNOS5410_L2_OPTION(_nr)           \
+	(EXYNOS5410_L2_CONFIGURATION(_nr) + 0x8)
+
+#define EXYNOS5410_CORE_CONFIGURATION(_nr)        \
+	(S5P_ARM_CORE0_CONFIGURATION + ((_nr) * 0x80))
+#define EXYNOS5410_CORE_STATUS(_nr)               \
+	(EXYNOS5410_CORE_CONFIGURATION(_nr) + 0x4)
+#define EXYNOS5410_CORE_OPTION(_nr)               \
+	(EXYNOS5410_CORE_CONFIGURATION(_nr) + 0x8)
+
+#define EXYNOS5_PA_CCI                  0x10D20000
diff --git a/arch/arm/mach-exynos/edcs_status.c b/arch/arm/mach-exynos/edcs_status.c
new file mode 100644
index 0000000..bff1e7f
--- /dev/null
+++ b/arch/arm/mach-exynos/edcs_status.c
@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ * Author: Tarek Dakhran <t.dakhran@samsung.com>
+ *
+ * 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.
+ *
+ * EDCS(EXYNOS dual cluster support) for Exynos5410 SoC.
+ */
+
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <asm/uaccess.h>
+
+#include "edcs.h"
+
+int edcs_check_status(char *info)
+{
+	size_t it = 30;
+	int i;
+
+	void __iomem *cci_base;
+
+	cci_base = ioremap(EXYNOS5_PA_CCI, SZ_64K);
+	if (!cci_base)
+		return -ENOMEM;
+
+	if ((__raw_readl(EXYNOS5410_COMMON_STATUS(0)) & 0x3) == 3)
+		info[it] = '1';
+	it += 3;
+
+	for (i = 0; i < 4; i++) {
+		if ((__raw_readl(EXYNOS5410_CORE_STATUS(i)) & 0x3) == 3)
+			info[it] = '1';
+		it += 3;
+	}
+
+	if ((__raw_readl(EXYNOS5410_L2_STATUS(0)) & 0x3)	== 3)
+		info[it] = '1';
+	it += 3;
+
+	if ((readl(cci_base + 0x4000 + 1 * 0x1000) & 0x3) == 3)
+		info[it] = '1';
+
+	it += 10;
+
+	if ((__raw_readl(EXYNOS5410_COMMON_STATUS(1)) & 0x3) == 3)
+		info[it] = '1';
+	it += 3;
+
+	for (i = 4; i < 8; i++) {
+		if ((__raw_readl(EXYNOS5410_CORE_STATUS(i)) & 0x3) == 3)
+			info[it] = '1';
+		it += 3;
+	}
+
+	if ((__raw_readl(EXYNOS5410_L2_STATUS(1)) & 0x3) == 3)
+		info[it] = '1';
+	it += 3;
+
+	if ((readl(cci_base + 0x4000 + 0 * 0x1000) & 0x3) == 3)
+		info[it] = '1';
+
+	iounmap(cci_base);
+	return 0;
+}
+
+static ssize_t edcs_status_read(struct file *file, char __user *buf,
+				size_t len, loff_t *pos)
+{
+
+	char info[] = "\tC  0  1  2  3 L2 CCI\n"
+		"[A15]   0  0  0  0  0  0  0\n"
+		" [A7]   0  0  0  0  0  0  0\n";
+	size_t count = sizeof(info);
+	edcs_check_status(info);
+	return simple_read_from_buffer(buf, len, pos, info, count);
+}
+
+static const struct file_operations edcs_status_fops = {
+	.read		= edcs_status_read,
+	.owner		= THIS_MODULE,
+};
+static struct miscdevice edcs_status_device = {
+	.name = "edcs_status",
+	.minor = 255,
+	.fops = &edcs_status_fops,
+};
+
+static int __init edcs_dev_init(void)
+{
+	struct device_node *node;
+	int ret;
+	if (!cci_probed())
+		return -ENODEV;
+
+	node = of_find_compatible_node(NULL, NULL, "samsung,edcs");
+	if (!node)
+		return -ENODEV;
+
+	ret = misc_register(&edcs_status_device);
+	if (ret) {
+		pr_err("EDCS: edcs_status device is not registered\n");
+		return ret;
+	}
+	pr_info("EDCS: edcs_status device registered\n");
+	return 0;
+}
+device_initcall(edcs_dev_init);
-- 
1.8.1.5