diff options
Diffstat (limited to 'arch/arm/mach-msm/platsmp.c')
| -rw-r--r-- | arch/arm/mach-msm/platsmp.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/arch/arm/mach-msm/platsmp.c b/arch/arm/mach-msm/platsmp.c new file mode 100644 index 000000000000..0f427bc94447 --- /dev/null +++ b/arch/arm/mach-msm/platsmp.c @@ -0,0 +1,166 @@ +/* + * Copyright (C) 2002 ARM Ltd. + * All Rights Reserved + * Copyright (c) 2010, Code Aurora Forum. All rights reserved. + * + * 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/errno.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/jiffies.h> +#include <linux/smp.h> +#include <linux/io.h> + +#include <asm/hardware/gic.h> +#include <asm/cacheflush.h> +#include <asm/mach-types.h> + +#include <mach/msm_iomap.h> + +#include "scm-boot.h" + +#define VDD_SC1_ARRAY_CLAMP_GFS_CTL 0x15A0 +#define SCSS_CPU1CORE_RESET 0xD80 +#define SCSS_DBG_STATUS_CORE_PWRDUP 0xE64 + +/* Mask for edge trigger PPIs except AVS_SVICINT and AVS_SVICINTSWDONE */ +#define GIC_PPI_EDGE_MASK 0xFFFFD7FF + +extern void msm_secondary_startup(void); +/* + * control for which core is the next to come out of the secondary + * boot "holding pen". + */ +volatile int pen_release = -1; + +static DEFINE_SPINLOCK(boot_lock); + +void __cpuinit platform_secondary_init(unsigned int cpu) +{ + /* Configure edge-triggered PPIs */ + writel(GIC_PPI_EDGE_MASK, MSM_QGIC_DIST_BASE + GIC_DIST_CONFIG + 4); + + /* + * 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 __cpuinit void prepare_cold_cpu(unsigned int cpu) +{ + int ret; + ret = scm_set_boot_addr(virt_to_phys(msm_secondary_startup), + SCM_FLAG_COLDBOOT_CPU1); + if (ret == 0) { + void *sc1_base_ptr; + sc1_base_ptr = ioremap_nocache(0x00902000, SZ_4K*2); + if (sc1_base_ptr) { + writel(0, sc1_base_ptr + VDD_SC1_ARRAY_CLAMP_GFS_CTL); + writel(0, sc1_base_ptr + SCSS_CPU1CORE_RESET); + writel(3, sc1_base_ptr + SCSS_DBG_STATUS_CORE_PWRDUP); + iounmap(sc1_base_ptr); + } + } else + printk(KERN_DEBUG "Failed to set secondary core boot " + "address\n"); +} + +int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle) +{ + unsigned long timeout; + static int cold_boot_done; + + /* Only need to bring cpu out of reset this way once */ + if (cold_boot_done == false) { + prepare_cold_cpu(cpu); + cold_boot_done = true; + } + + /* + * 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; + __cpuc_flush_dcache_area((void *)&pen_release, sizeof(pen_release)); + outer_clean_range(__pa(&pen_release), __pa(&pen_release + 1)); + + /* + * Send the secondary CPU a soft interrupt, thereby causing + * the boot monitor to read the system wide flags register, + * and branch to the address found there. + */ + smp_cross_call(cpumask_of(cpu), 1); + + 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. The msm8x60 + * does not support the ARM SCU, so just set the possible cpu mask to + * NR_CPUS. + */ +void __init smp_init_cpus(void) +{ + unsigned int i; + + for (i = 0; i < NR_CPUS; i++) + set_cpu_possible(i, true); +} + +void __init platform_smp_prepare_cpus(unsigned int max_cpus) +{ + int i; + + /* + * Initialise the present map, which describes the set of CPUs + * actually populated at the present time. + */ + for (i = 0; i < max_cpus; i++) + set_cpu_present(i, true); +} |