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 <linux/pgtable.h>
  17 #include <asm/pci-bridge.h>
  18 #include <asm/mpic.h>
  19 #include <asm/cacheflush.h>
  20 #include <asm/inst.h>
  21
  22 #include <sysdev/fsl_soc.h>
  23
  24 #include "mpc86xx.h"
  25
  26 extern void __secondary_start_mpc86xx(void);
  27
  28 #define MCM_PORT_CONFIG_OFFSET  0x10
  29
  30 /* Offset from CCSRBAR */
  31 #define MPC86xx_MCM_OFFSET      (0x1000)
  32 #define MPC86xx_MCM_SIZE        (0x1000)
  33
  34 static void __init
  35 smp_86xx_release_core(int nr)
  36 {
  37         __be32 __iomem *mcm_vaddr;
  38         unsigned long pcr;
  39
  40         if (nr < 0 || nr >= NR_CPUS)
  41                 return;
  42
  43         /*
  44          * Startup Core #nr.
  45          */
  46         mcm_vaddr = ioremap(get_immrbase() + MPC86xx_MCM_OFFSET,
  47                             MPC86xx_MCM_SIZE);
  48         pcr = in_be32(mcm_vaddr + (MCM_PORT_CONFIG_OFFSET >> 2));
  49         pcr |= 1 << (nr + 24);
  50         out_be32(mcm_vaddr + (MCM_PORT_CONFIG_OFFSET >> 2), pcr);
  51
  52         iounmap(mcm_vaddr);
  53 }
  54
  55
  56 static int __init
  57 smp_86xx_kick_cpu(int nr)
  58 {
  59         unsigned int save_vector;
  60         unsigned long target, flags;
  61         int n = 0;
  62         unsigned int *vector = (unsigned int *)(KERNELBASE + 0x100);
  63
  64         if (nr < 0 || nr >= NR_CPUS)
  65                 return -ENOENT;
  66
  67         pr_debug("smp_86xx_kick_cpu: kick CPU #%d\n", nr);
  68
  69         local_irq_save(flags);
  70
  71         /* Save reset vector */
  72         save_vector = *vector;
  73
  74         /* Setup fake reset vector to call __secondary_start_mpc86xx. */
  75         target = (unsigned long) __secondary_start_mpc86xx;
  76         patch_branch((struct ppc_inst *)vector, target, BRANCH_SET_LINK);
  77
  78         /* Kick that CPU */
  79         smp_86xx_release_core(nr);
  80
  81         /* Wait a bit for the CPU to take the exception. */
  82         while ((__secondary_hold_acknowledge != nr) && (n++, n < 1000))
  83                 mdelay(1);
  84
  85         /* Restore the exception vector */
  86         patch_instruction((struct ppc_inst *)vector, ppc_inst(save_vector));
  87
  88         local_irq_restore(flags);
  89
  90         pr_debug("wait CPU #%d for %d msecs.\n", nr, n);
  91
  92         return 0;
  93 }
  94
  95
  96 static void __init
  97 smp_86xx_setup_cpu(int cpu_nr)
  98 {
  99         mpic_setup_this_cpu();
 100 }
 101
 102
 103 struct smp_ops_t smp_86xx_ops = {
 104         .cause_nmi_ipi = NULL,
 105         .message_pass = smp_mpic_message_pass,
 106         .probe = smp_mpic_probe,
 107         .kick_cpu = smp_86xx_kick_cpu,
 108         .setup_cpu = smp_86xx_setup_cpu,
 109         .take_timebase = smp_generic_take_timebase,
 110         .give_timebase = smp_generic_give_timebase,
 111 };
 112
 113
 114 void __init
 115 mpc86xx_smp_init(void)
 116 {
 117         smp_ops = &smp_86xx_ops;
 118 }