arch/powerpc/platforms/86xx/mpc86xx_smp.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Author: Xianghua Xiao <x.xiao@freescale.com>
   4  *         Zhang Wei <wei.zhang@freescale.com>
   5  *
   6  * Copyright 2006 Freescale Semiconductor Inc.
   7  */
   8
   9 #include <linux/stddef.h>
  10 #include <linux/kernel.h>
  11 #include <linux/init.h>
  12 #include <linux/delay.h>
  13
  14 #include <asm/code-patching.h>
  15 #include <asm/page.h>
  16 #include <asm/pgtable.h>
  17 #include <asm/pci-bridge.h>
  18 #include <asm/mpic.h>
  19 #include <asm/cacheflush.h>
  20
  21 #include <sysdev/fsl_soc.h>
  22
  23 #include "mpc86xx.h"
  24
  25 extern void __secondary_start_mpc86xx(void);
  26
  27 #define MCM_PORT_CONFIG_OFFSET  0x10
  28
  29 /* Offset from CCSRBAR */
  30 #define MPC86xx_MCM_OFFSET      (0x1000)
  31 #define MPC86xx_MCM_SIZE        (0x1000)
  32
  33 static void __init
  34 smp_86xx_release_core(int nr)
  35 {
  36         __be32 __iomem *mcm_vaddr;
  37         unsigned long pcr;
  38
  39         if (nr < 0 || nr >= NR_CPUS)
  40                 return;
  41
  42         /*
  43          * Startup Core #nr.
  44          */
  45         mcm_vaddr = ioremap(get_immrbase() + MPC86xx_MCM_OFFSET,
  46                             MPC86xx_MCM_SIZE);
  47         pcr = in_be32(mcm_vaddr + (MCM_PORT_CONFIG_OFFSET >> 2));
  48         pcr |= 1 << (nr + 24);
  49         out_be32(mcm_vaddr + (MCM_PORT_CONFIG_OFFSET >> 2), pcr);
  50
  51         iounmap(mcm_vaddr);
  52 }
  53
  54
  55 static int __init
  56 smp_86xx_kick_cpu(int nr)
  57 {
  58         unsigned int save_vector;
  59         unsigned long target, flags;
  60         int n = 0;
  61         unsigned int *vector = (unsigned int *)(KERNELBASE + 0x100);
  62
  63         if (nr < 0 || nr >= NR_CPUS)
  64                 return -ENOENT;
  65
  66         pr_debug("smp_86xx_kick_cpu: kick CPU #%d\n", nr);
  67
  68         local_irq_save(flags);
  69
  70         /* Save reset vector */
  71         save_vector = *vector;
  72
  73         /* Setup fake reset vector to call __secondary_start_mpc86xx. */
  74         target = (unsigned long) __secondary_start_mpc86xx;
  75         patch_branch(vector, target, BRANCH_SET_LINK);
  76
  77         /* Kick that CPU */
  78         smp_86xx_release_core(nr);
  79
  80         /* Wait a bit for the CPU to take the exception. */
  81         while ((__secondary_hold_acknowledge != nr) && (n++, n < 1000))
  82                 mdelay(1);
  83
  84         /* Restore the exception vector */
  85         patch_instruction(vector, save_vector);
  86
  87         local_irq_restore(flags);
  88
  89         pr_debug("wait CPU #%d for %d msecs.\n", nr, n);
  90
  91         return 0;
  92 }
  93
  94
  95 static void __init
  96 smp_86xx_setup_cpu(int cpu_nr)
  97 {
  98         mpic_setup_this_cpu();
  99 }
 100
 101
 102 struct smp_ops_t smp_86xx_ops = {
 103         .cause_nmi_ipi = NULL,
 104         .message_pass = smp_mpic_message_pass,
 105         .probe = smp_mpic_probe,
 106         .kick_cpu = smp_86xx_kick_cpu,
 107         .setup_cpu = smp_86xx_setup_cpu,
 108         .take_timebase = smp_generic_take_timebase,
 109         .give_timebase = smp_generic_give_timebase,
 110 };
 111
 112
 113 void __init
 114 mpc86xx_smp_init(void)
 115 {
 116         smp_ops = &smp_86xx_ops;
 117 }