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author | Arnd Bergmann <arnd@arndb.de> | 2012-12-02 15:12:47 +0100 |
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committer | Arnd Bergmann <arnd@arndb.de> | 2013-03-12 17:39:47 +0100 |
commit | a7ed099ffc8edf2a6dccd8a22469347f5cdcfa57 (patch) | |
tree | b56901430602574233ad23008cfd7c23babd20c3 /arch/arm/mach-spear/platsmp.c | |
parent | 0ec05c3e4ac6548fcab4b6a74254a22ef251e1fd (diff) | |
download | op-kernel-dev-a7ed099ffc8edf2a6dccd8a22469347f5cdcfa57.zip op-kernel-dev-a7ed099ffc8edf2a6dccd8a22469347f5cdcfa57.tar.gz |
ARM: spear: move all files to mach-spear
There are no conflicting files between the three mach-spear* directories
and plat-spear any more, so we can now move all file to a common
mach-spear directory.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Diffstat (limited to 'arch/arm/mach-spear/platsmp.c')
-rw-r--r-- | arch/arm/mach-spear/platsmp.c | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/arch/arm/mach-spear/platsmp.c b/arch/arm/mach-spear/platsmp.c new file mode 100644 index 0000000..af4ade6 --- /dev/null +++ b/arch/arm/mach-spear/platsmp.c @@ -0,0 +1,130 @@ +/* + * arch/arm/mach-spear13xx/platsmp.c + * + * based upon linux/arch/arm/mach-realview/platsmp.c + * + * Copyright (C) 2012 ST Microelectronics Ltd. + * Shiraz Hashim <shiraz.hashim@st.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. + */ + +#include <linux/delay.h> +#include <linux/jiffies.h> +#include <linux/io.h> +#include <linux/smp.h> +#include <linux/irqchip/arm-gic.h> +#include <asm/cacheflush.h> +#include <asm/smp_scu.h> +#include <mach/spear.h> +#include <mach/generic.h> + +static DEFINE_SPINLOCK(boot_lock); + +static void __iomem *scu_base = IOMEM(VA_SCU_BASE); + +static void __cpuinit spear13xx_secondary_init(unsigned int cpu) +{ + /* + * if any interrupts are already enabled for the primary + * core (e.g. timer irq), then they will not have been enabled + * for us: do so + */ + gic_secondary_init(0); + + /* + * let the primary processor know we're out of the + * pen, then head off into the C entry point + */ + pen_release = -1; + smp_wmb(); + + /* + * Synchronise with the boot thread. + */ + spin_lock(&boot_lock); + spin_unlock(&boot_lock); +} + +static int __cpuinit spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle) +{ + unsigned long timeout; + + /* + * set synchronisation state between this boot processor + * and the secondary one + */ + spin_lock(&boot_lock); + + /* + * The secondary processor is waiting to be released from + * the holding pen - release it, then wait for it to flag + * that it has been released by resetting pen_release. + * + * Note that "pen_release" is the hardware CPU ID, whereas + * "cpu" is Linux's internal ID. + */ + pen_release = cpu; + flush_cache_all(); + outer_flush_all(); + + timeout = jiffies + (1 * HZ); + while (time_before(jiffies, timeout)) { + smp_rmb(); + if (pen_release == -1) + break; + + udelay(10); + } + + /* + * now the secondary core is starting up let it run its + * calibrations, then wait for it to finish + */ + spin_unlock(&boot_lock); + + return pen_release != -1 ? -ENOSYS : 0; +} + +/* + * Initialise the CPU possible map early - this describes the CPUs + * which may be present or become present in the system. + */ +static void __init spear13xx_smp_init_cpus(void) +{ + unsigned int i, ncores = scu_get_core_count(scu_base); + + if (ncores > nr_cpu_ids) { + pr_warn("SMP: %u cores greater than maximum (%u), clipping\n", + ncores, nr_cpu_ids); + ncores = nr_cpu_ids; + } + + for (i = 0; i < ncores; i++) + set_cpu_possible(i, true); +} + +static void __init spear13xx_smp_prepare_cpus(unsigned int max_cpus) +{ + + scu_enable(scu_base); + + /* + * Write the address of secondary startup into the system-wide location + * (presently it is in SRAM). The BootMonitor waits until it receives a + * soft interrupt, and then the secondary CPU branches to this address. + */ + __raw_writel(virt_to_phys(spear13xx_secondary_startup), SYS_LOCATION); +} + +struct smp_operations spear13xx_smp_ops __initdata = { + .smp_init_cpus = spear13xx_smp_init_cpus, + .smp_prepare_cpus = spear13xx_smp_prepare_cpus, + .smp_secondary_init = spear13xx_secondary_init, + .smp_boot_secondary = spear13xx_boot_secondary, +#ifdef CONFIG_HOTPLUG_CPU + .cpu_die = spear13xx_cpu_die, +#endif +}; |