cregit-Linux how code gets into the kernel

Release 4.14 arch/powerpc/platforms/cell/smp.c

/*
 * SMP support for BPA machines.
 *
 * Dave Engebretsen, Peter Bergner, and
 * Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
 *
 * Plus various changes from other IBM teams...
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */


#undef DEBUG

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/cache.h>
#include <linux/err.h>
#include <linux/device.h>
#include <linux/cpu.h>

#include <asm/ptrace.h>
#include <linux/atomic.h>
#include <asm/irq.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/smp.h>
#include <asm/paca.h>
#include <asm/machdep.h>
#include <asm/cputable.h>
#include <asm/firmware.h>
#include <asm/rtas.h>
#include <asm/cputhreads.h>
#include <asm/code-patching.h>

#include "interrupt.h"
#include <asm/udbg.h>

#ifdef DEBUG

#define DBG(fmt...) udbg_printf(fmt)
#else

#define DBG(fmt...)
#endif

/*
 * The Primary thread of each non-boot processor was started from the OF client
 * interface by prom_hold_cpus and is spinning on secondary_hold_spinloop.
 */

static cpumask_t of_spin_map;

/**
 * smp_startup_cpu() - start the given cpu
 *
 * At boot time, there is nothing to do for primary threads which were
 * started from Open Firmware.  For anything else, call RTAS with the
 * appropriate start location.
 *
 * Returns:
 *      0       - failure
 *      1       - success
 */

static inline int smp_startup_cpu(unsigned int lcpu) { int status; unsigned long start_here = __pa(ppc_function_entry(generic_secondary_smp_init)); unsigned int pcpu; int start_cpu; if (cpumask_test_cpu(lcpu, &of_spin_map)) /* Already started by OF and sitting in spin loop */ return 1; pcpu = get_hard_smp_processor_id(lcpu); /* Fixup atomic count: it exited inside IRQ handler. */ task_thread_info(paca[lcpu].__current)->preempt_count = 0; /* * If the RTAS start-cpu token does not exist then presume the * cpu is already spinning. */ start_cpu = rtas_token("start-cpu"); if (start_cpu == RTAS_UNKNOWN_SERVICE) return 1; status = rtas_call(start_cpu, 3, 1, NULL, pcpu, start_here, lcpu); if (status != 0) { printk(KERN_ERR "start-cpu failed: %i\n", status); return 0; } return 1; }

Contributors

PersonTokensPropCommitsCommitProp
Arnd Bergmann11892.91%120.00%
Al Viro32.36%120.00%
Anton Blanchard32.36%120.00%
Motohiro Kosaki21.57%120.00%
Olof Johansson10.79%120.00%
Total127100.00%5100.00%


static void smp_cell_setup_cpu(int cpu) { if (cpu != boot_cpuid) iic_setup_cpu(); /* * change default DABRX to allow user watchpoints */ mtspr(SPRN_DABRX, DABRX_KERNEL | DABRX_USER); }

Contributors

PersonTokensPropCommitsCommitProp
Arnd Bergmann28100.00%2100.00%
Total28100.00%2100.00%


static int smp_cell_kick_cpu(int nr) { if (nr < 0 || nr >= nr_cpu_ids) return -EINVAL; if (!smp_startup_cpu(nr)) return -ENOENT; /* * The processor is currently spinning, waiting for the * cpu_start field to become non-zero After we set cpu_start, * the processor will continue on to secondary_start */ paca[nr].cpu_start = 1; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Arnd Bergmann3266.67%125.00%
Santosh Sivaraj816.67%250.00%
Michael Ellerman816.67%125.00%
Total48100.00%4100.00%

static struct smp_ops_t bpa_iic_smp_ops = { .message_pass = iic_message_pass, .probe = iic_request_IPIs, .kick_cpu = smp_cell_kick_cpu, .setup_cpu = smp_cell_setup_cpu, .cpu_bootable = smp_generic_cpu_bootable, }; /* This is called very early */
void __init smp_init_cell(void) { int i; DBG(" -> smp_init_cell()\n"); smp_ops = &bpa_iic_smp_ops; /* Mark threads which are still spinning in hold loops. */ if (cpu_has_feature(CPU_FTR_SMT)) { for_each_present_cpu(i) { if (cpu_thread_in_core(i) == 0) cpumask_set_cpu(i, &of_spin_map); } } else cpumask_copy(&of_spin_map, cpu_present_mask); cpumask_clear_cpu(boot_cpuid, &of_spin_map); /* Non-lpar has additional take/give timebase */ if (rtas_token("freeze-time-base") != RTAS_UNKNOWN_SERVICE) { smp_ops->give_timebase = rtas_give_timebase; smp_ops->take_timebase = rtas_take_timebase; } DBG(" <- smp_init_cell()\n"); }

Contributors

PersonTokensPropCommitsCommitProp
Arnd Bergmann8585.00%125.00%
Motohiro Kosaki1010.00%125.00%
Milton D. Miller II33.00%125.00%
Benjamin Herrenschmidt22.00%125.00%
Total100100.00%4100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Arnd Bergmann39787.83%211.11%
Motohiro Kosaki122.65%15.56%
Michael Ellerman91.99%211.11%
Santosh Sivaraj81.77%211.11%
Anton Blanchard61.33%15.56%
Milton D. Miller II51.11%211.11%
Benjamin Herrenschmidt51.11%211.11%
Al Viro30.66%15.56%
Will Schmidt30.66%15.56%
Andy Fleming10.22%15.56%
Olof Johansson10.22%15.56%
Kay Sievers10.22%15.56%
Arun Sharma10.22%15.56%
Total452100.00%18100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.