LXR linux/arch/powerpc/sysdev/grackle.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Functions for setting up and using a MPC106 northbridge
   4 * Extracted from arch/powerpc/platforms/powermac/pci.c.
   5 *
   6 * Copyright (C) 2003 Benjamin Herrenschmuidt (benh@kernel.crashing.org)
   7 * Copyright (C) 1997 Paul Mackerras (paulus@samba.org)
   8 */
   9#include <linux/kernel.h>
  10#include <linux/pci.h>
  11#include <linux/init.h>
  12
  13#include <asm/io.h>
  14#include <asm/prom.h>
  15#include <asm/pci-bridge.h>
  16#include <asm/grackle.h>
  17
  18#define GRACKLE_CFA(b, d, o)    (0x80 | ((b) << 8) | ((d) << 16) \
  19                                 | (((o) & ~3) << 24))
  20
  21#define GRACKLE_PICR1_STG               0x00000040
  22#define GRACKLE_PICR1_LOOPSNOOP         0x00000010
  23
  24/* N.B. this is called before bridges is initialized, so we can't
  25   use grackle_pcibios_{read,write}_config_dword. */
  26static inline void grackle_set_stg(struct pci_controller* bp, int enable)
  27{
  28        unsigned int val;
  29
  30        out_be32(bp->cfg_addr, GRACKLE_CFA(0, 0, 0xa8));
  31        val = in_le32(bp->cfg_data);
  32        val = enable? (val | GRACKLE_PICR1_STG) :
  33                (val & ~GRACKLE_PICR1_STG);
  34        out_be32(bp->cfg_addr, GRACKLE_CFA(0, 0, 0xa8));
  35        out_le32(bp->cfg_data, val);
  36        (void)in_le32(bp->cfg_data);
  37}
  38
  39static inline void grackle_set_loop_snoop(struct pci_controller *bp, int enable)
  40{
  41        unsigned int val;
  42
  43        out_be32(bp->cfg_addr, GRACKLE_CFA(0, 0, 0xa8));
  44        val = in_le32(bp->cfg_data);
  45        val = enable? (val | GRACKLE_PICR1_LOOPSNOOP) :
  46                (val & ~GRACKLE_PICR1_LOOPSNOOP);
  47        out_be32(bp->cfg_addr, GRACKLE_CFA(0, 0, 0xa8));
  48        out_le32(bp->cfg_data, val);
  49        (void)in_le32(bp->cfg_data);
  50}
  51
  52void __init setup_grackle(struct pci_controller *hose)
  53{
  54        setup_indirect_pci(hose, 0xfec00000, 0xfee00000, 0);
  55        if (of_machine_is_compatible("PowerMac1,1"))
  56                pci_add_flags(PCI_REASSIGN_ALL_BUS);
  57        if (of_machine_is_compatible("AAPL,PowerBook1998"))
  58                grackle_set_loop_snoop(hose, 1);
  59#if 0   /* Disabled for now, HW problems ??? */
  60        grackle_set_stg(hose, 1);
  61#endif
  62}
  63