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Release 4.11 arch/arm/mach-vexpress/dcscb.c

/*
 * arch/arm/mach-vexpress/dcscb.c - Dual Cluster System Configuration Block
 *
 * Created by:  Nicolas Pitre, May 2012
 * Copyright:   (C) 2012-2013  Linaro Limited
 *
 * 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/init.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/errno.h>
#include <linux/of_address.h>
#include <linux/vexpress.h>
#include <linux/arm-cci.h>

#include <asm/mcpm.h>
#include <asm/proc-fns.h>
#include <asm/cacheflush.h>
#include <asm/cputype.h>
#include <asm/cp15.h>



#define RST_HOLD0	0x0

#define RST_HOLD1	0x4

#define SYS_SWRESET	0x8

#define RST_STAT0	0xc

#define RST_STAT1	0x10

#define EAG_CFG_R	0x20

#define EAG_CFG_W	0x24

#define KFC_CFG_R	0x28

#define KFC_CFG_W	0x2c

#define DCS_CFG_R	0x30


static void __iomem *dcscb_base;

static int dcscb_allcpus_mask[2];


static int dcscb_cpu_powerup(unsigned int cpu, unsigned int cluster) { unsigned int rst_hold, cpumask = (1 << cpu); pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster); if (cluster >= 2 || !(cpumask & dcscb_allcpus_mask[cluster])) return -EINVAL; rst_hold = readl_relaxed(dcscb_base + RST_HOLD0 + cluster * 4); rst_hold &= ~(cpumask | (cpumask << 4)); writel_relaxed(rst_hold, dcscb_base + RST_HOLD0 + cluster * 4); return 0; }

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Nico Pitre99100.00%3100.00%
Total99100.00%3100.00%


static int dcscb_cluster_powerup(unsigned int cluster) { unsigned int rst_hold; pr_debug("%s: cluster %u\n", __func__, cluster); if (cluster >= 2) return -EINVAL; /* remove cluster reset and add individual CPU's reset */ rst_hold = readl_relaxed(dcscb_base + RST_HOLD0 + cluster * 4); rst_hold &= ~(1 << 8); rst_hold |= dcscb_allcpus_mask[cluster]; writel_relaxed(rst_hold, dcscb_base + RST_HOLD0 + cluster * 4); return 0; }

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static void dcscb_cpu_powerdown_prepare(unsigned int cpu, unsigned int cluster) { unsigned int rst_hold; pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster); BUG_ON(cluster >= 2 || !((1 << cpu) & dcscb_allcpus_mask[cluster])); rst_hold = readl_relaxed(dcscb_base + RST_HOLD0 + cluster * 4); rst_hold |= (1 << cpu); writel_relaxed(rst_hold, dcscb_base + RST_HOLD0 + cluster * 4); }

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static void dcscb_cluster_powerdown_prepare(unsigned int cluster) { unsigned int rst_hold; pr_debug("%s: cluster %u\n", __func__, cluster); BUG_ON(cluster >= 2); rst_hold = readl_relaxed(dcscb_base + RST_HOLD0 + cluster * 4); rst_hold |= (1 << 8); writel_relaxed(rst_hold, dcscb_base + RST_HOLD0 + cluster * 4); }

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Nico Pitre5382.81%480.00%
Dave P Martin1117.19%120.00%
Total64100.00%5100.00%


static void dcscb_cpu_cache_disable(void) { /* Disable and flush the local CPU cache. */ v7_exit_coherency_flush(louis); }

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Nico Pitre1392.86%375.00%
Dave P Martin17.14%125.00%
Total14100.00%4100.00%


static void dcscb_cluster_cache_disable(void) { /* Flush all cache levels for this cluster. */ v7_exit_coherency_flush(all); /* * A full outer cache flush could be needed at this point * on platforms with such a cache, depending on where the * outer cache sits. In some cases the notion of a "last * cluster standing" would need to be implemented if the * outer cache is shared across clusters. In any case, when * the outer cache needs flushing, there is no concurrent * access to the cache controller to worry about and no * special locking besides what is already provided by the * MCPM state machinery is needed. */ /* * Disable cluster-level coherency by masking * incoming snoops and DVM messages: */ cci_disable_port_by_cpu(read_cpuid_mpidr()); }

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Nico Pitre1986.36%266.67%
Dave P Martin313.64%133.33%
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static const struct mcpm_platform_ops dcscb_power_ops = { .cpu_powerup = dcscb_cpu_powerup, .cluster_powerup = dcscb_cluster_powerup, .cpu_powerdown_prepare = dcscb_cpu_powerdown_prepare, .cluster_powerdown_prepare = dcscb_cluster_powerdown_prepare, .cpu_cache_disable = dcscb_cpu_cache_disable, .cluster_cache_disable = dcscb_cluster_cache_disable, }; extern void dcscb_power_up_setup(unsigned int affinity_level);
static int __init dcscb_init(void) { struct device_node *node; unsigned int cfg; int ret; if (!cci_probed()) return -ENODEV; node = of_find_compatible_node(NULL, NULL, "arm,rtsm,dcscb"); if (!node) return -ENODEV; dcscb_base = of_iomap(node, 0); if (!dcscb_base) return -EADDRNOTAVAIL; cfg = readl_relaxed(dcscb_base + DCS_CFG_R); dcscb_allcpus_mask[0] = (1 << (((cfg >> 16) >> (0 << 2)) & 0xf)) - 1; dcscb_allcpus_mask[1] = (1 << (((cfg >> 16) >> (1 << 2)) & 0xf)) - 1; ret = mcpm_platform_register(&dcscb_power_ops); if (!ret) ret = mcpm_sync_init(dcscb_power_up_setup); if (ret) { iounmap(dcscb_base); return ret; } pr_info("VExpress DCSCB support installed\n"); /* * Future entries into the kernel can now go * through the cluster entry vectors. */ vexpress_flags_set(__pa_symbol(mcpm_entry_point)); return 0; }

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Nico Pitre16487.70%250.00%
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Florian Fainelli10.53%125.00%
Total187100.00%4100.00%

early_initcall(dcscb_init);

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Nico Pitre64192.76%675.00%
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Florian Fainelli10.14%112.50%
Total691100.00%8100.00%
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