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. */ 26 static 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 39 static 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 52 void __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