arch/powerpc/platforms/cell/pervasive.c

   1 /*
   2  * CBE Pervasive Monitor and Debug
   3  *
   4  * (C) Copyright IBM Corporation 2005
   5  *
   6  * Authors: Maximino Aguilar (maguilar@us.ibm.com)
   7  *          Michael N. Day (mnday@us.ibm.com)
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2, or (at your option)
  12  * any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  */
  23
  24 #undef DEBUG
  25
  26 #include <linux/interrupt.h>
  27 #include <linux/irq.h>
  28 #include <linux/percpu.h>
  29 #include <linux/types.h>
  30 #include <linux/kallsyms.h>
  31
  32 #include <asm/io.h>
  33 #include <asm/machdep.h>
  34 #include <asm/prom.h>
  35 #include <asm/pgtable.h>
  36 #include <asm/reg.h>
  37 #include <asm/cell-regs.h>
  38
  39 #include "pervasive.h"
  40
  41 static void cbe_power_save(void)
  42 {
  43         unsigned long ctrl, thread_switch_control;
  44
  45         /* Ensure our interrupt state is properly tracked */
  46         if (!prep_irq_for_idle())
  47                 return;
  48
  49         ctrl = mfspr(SPRN_CTRLF);
  50
  51         /* Enable DEC and EE interrupt request */
  52         thread_switch_control  = mfspr(SPRN_TSC_CELL);
  53         thread_switch_control |= TSC_CELL_EE_ENABLE | TSC_CELL_EE_BOOST;
  54
  55         switch (ctrl & CTRL_CT) {
  56         case CTRL_CT0:
  57                 thread_switch_control |= TSC_CELL_DEC_ENABLE_0;
  58                 break;
  59         case CTRL_CT1:
  60                 thread_switch_control |= TSC_CELL_DEC_ENABLE_1;
  61                 break;
  62         default:
  63                 printk(KERN_WARNING "%s: unknown configuration\n",
  64                         __func__);
  65                 break;
  66         }
  67         mtspr(SPRN_TSC_CELL, thread_switch_control);
  68
  69         /*
  70          * go into low thread priority, medium priority will be
  71          * restored for us after wake-up.
  72          */
  73         HMT_low();
  74
  75         /*
  76          * atomically disable thread execution and runlatch.
  77          * External and Decrementer exceptions are still handled when the
  78          * thread is disabled but now enter in cbe_system_reset_exception()
  79          */
  80         ctrl &= ~(CTRL_RUNLATCH | CTRL_TE);
  81         mtspr(SPRN_CTRLT, ctrl);
  82
  83         /* Re-enable interrupts in MSR */
  84         __hard_irq_enable();
  85 }
  86
  87 static int cbe_system_reset_exception(struct pt_regs *regs)
  88 {
  89         switch (regs->msr & SRR1_WAKEMASK) {
  90         case SRR1_WAKEEE:
  91                 do_IRQ(regs);
  92                 break;
  93         case SRR1_WAKEDEC:
  94                 timer_interrupt(regs);
  95                 break;
  96         case SRR1_WAKEMT:
  97                 return cbe_sysreset_hack();
  98 #ifdef CONFIG_CBE_RAS
  99         case SRR1_WAKESYSERR:
 100                 cbe_system_error_exception(regs);
 101                 break;
 102         case SRR1_WAKETHERM:
 103                 cbe_thermal_exception(regs);
 104                 break;
 105 #endif /* CONFIG_CBE_RAS */
 106         default:
 107                 /* do system reset */
 108                 return 0;
 109         }
 110         /* everything handled */
 111         return 1;
 112 }
 113
 114 void __init cbe_pervasive_init(void)
 115 {
 116         int cpu;
 117
 118         if (!cpu_has_feature(CPU_FTR_PAUSE_ZERO))
 119                 return;
 120
 121         for_each_possible_cpu(cpu) {
 122                 struct cbe_pmd_regs __iomem *regs = cbe_get_cpu_pmd_regs(cpu);
 123                 if (!regs)
 124                         continue;
 125
 126                  /* Enable Pause(0) control bit */
 127                 out_be64(&regs->pmcr, in_be64(&regs->pmcr) |
 128                                             CBE_PMD_PAUSE_ZERO_CONTROL);
 129         }
 130
 131         ppc_md.power_save = cbe_power_save;
 132         ppc_md.system_reset_exception = cbe_system_reset_exception;
 133 }