arch/mips/pci/pci-tx4927.c

   1 /*
   2  * linux/arch/mips/pci/pci-tx4927.c
   3  *
   4  * Based on linux/arch/mips/txx9/rbtx4938/setup.c,
   5  *          and RBTX49xx patch from CELF patch archive.
   6  *
   7  * Copyright 2001, 2003-2005 MontaVista Software Inc.
   8  * Copyright (C) 2004 by Ralf Baechle (ralf@linux-mips.org)
   9  * (C) Copyright TOSHIBA CORPORATION 2000-2001, 2004-2007
  10  *
  11  * This file is subject to the terms and conditions of the GNU General Public
  12  * License.  See the file "COPYING" in the main directory of this archive
  13  * for more details.
  14  */
  15 #include <linux/init.h>
  16 #include <linux/pci.h>
  17 #include <linux/kernel.h>
  18 #include <linux/interrupt.h>
  19 #include <asm/txx9/generic.h>
  20 #include <asm/txx9/tx4927.h>
  21
  22 int __init tx4927_report_pciclk(void)
  23 {
  24         int pciclk = 0;
  25
  26         printk(KERN_INFO "PCIC --%s PCICLK:",
  27                (__raw_readq(&tx4927_ccfgptr->ccfg) & TX4927_CCFG_PCI66) ?
  28                " PCI66" : "");
  29         if (__raw_readq(&tx4927_ccfgptr->pcfg) & TX4927_PCFG_PCICLKEN_ALL) {
  30                 u64 ccfg = __raw_readq(&tx4927_ccfgptr->ccfg);
  31                 switch ((unsigned long)ccfg &
  32                         TX4927_CCFG_PCIDIVMODE_MASK) {
  33                 case TX4927_CCFG_PCIDIVMODE_2_5:
  34                         pciclk = txx9_cpu_clock * 2 / 5; break;
  35                 case TX4927_CCFG_PCIDIVMODE_3:
  36                         pciclk = txx9_cpu_clock / 3; break;
  37                 case TX4927_CCFG_PCIDIVMODE_5:
  38                         pciclk = txx9_cpu_clock / 5; break;
  39                 case TX4927_CCFG_PCIDIVMODE_6:
  40                         pciclk = txx9_cpu_clock / 6; break;
  41                 }
  42                 printk("Internal(%u.%uMHz)",
  43                        (pciclk + 50000) / 1000000,
  44                        ((pciclk + 50000) / 100000) % 10);
  45         } else {
  46                 printk("External");
  47                 pciclk = -1;
  48         }
  49         printk("\n");
  50         return pciclk;
  51 }
  52
  53 int __init tx4927_pciclk66_setup(void)
  54 {
  55         int pciclk;
  56
  57         /* Assert M66EN */
  58         tx4927_ccfg_set(TX4927_CCFG_PCI66);
  59         /* Double PCICLK (if possible) */
  60         if (__raw_readq(&tx4927_ccfgptr->pcfg) & TX4927_PCFG_PCICLKEN_ALL) {
  61                 unsigned int pcidivmode = 0;
  62                 u64 ccfg = __raw_readq(&tx4927_ccfgptr->ccfg);
  63                 pcidivmode = (unsigned long)ccfg &
  64                         TX4927_CCFG_PCIDIVMODE_MASK;
  65                 switch (pcidivmode) {
  66                 case TX4927_CCFG_PCIDIVMODE_5:
  67                 case TX4927_CCFG_PCIDIVMODE_2_5:
  68                         pcidivmode = TX4927_CCFG_PCIDIVMODE_2_5;
  69                         pciclk = txx9_cpu_clock * 2 / 5;
  70                         break;
  71                 case TX4927_CCFG_PCIDIVMODE_6:
  72                 case TX4927_CCFG_PCIDIVMODE_3:
  73                 default:
  74                         pcidivmode = TX4927_CCFG_PCIDIVMODE_3;
  75                         pciclk = txx9_cpu_clock / 3;
  76                 }
  77                 tx4927_ccfg_change(TX4927_CCFG_PCIDIVMODE_MASK,
  78                                    pcidivmode);
  79                 printk(KERN_DEBUG "PCICLK: ccfg:%08lx\n",
  80                        (unsigned long)__raw_readq(&tx4927_ccfgptr->ccfg));
  81         } else
  82                 pciclk = -1;
  83         return pciclk;
  84 }
  85
  86 void __init tx4927_setup_pcierr_irq(void)
  87 {
  88         if (request_irq(TXX9_IRQ_BASE + TX4927_IR_PCIERR,
  89                         tx4927_pcierr_interrupt,
  90                         IRQF_DISABLED, "PCI error",
  91                         (void *)TX4927_PCIC_REG))
  92                 printk(KERN_WARNING "Failed to request irq for PCIERR\n");
  93 }