arch/mips/pci/pci-tx4927.c

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