1 /* 2 * PowerNV LPC bus handling. 3 * 4 * Copyright 2013 IBM Corp. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12 #include <linux/kernel.h> 13 #include <linux/of.h> 14 #include <linux/bug.h> 15 16 #include <asm/machdep.h> 17 #include <asm/firmware.h> 18 #include <asm/xics.h> 19 #include <asm/opal.h> 20 21 static int opal_lpc_chip_id = -1; 22 23 static u8 opal_lpc_inb(unsigned long port) 24 { 25 int64_t rc; 26 uint32_t data; 27 28 if (opal_lpc_chip_id < 0 || port > 0xffff) 29 return 0xff; 30 rc = opal_lpc_read(opal_lpc_chip_id, OPAL_LPC_IO, port, &data, 1); 31 return rc ? 0xff : data; 32 } 33 34 static __le16 __opal_lpc_inw(unsigned long port) 35 { 36 int64_t rc; 37 uint32_t data; 38 39 if (opal_lpc_chip_id < 0 || port > 0xfffe) 40 return 0xffff; 41 if (port & 1) 42 return (__le16)opal_lpc_inb(port) << 8 | opal_lpc_inb(port + 1); 43 rc = opal_lpc_read(opal_lpc_chip_id, OPAL_LPC_IO, port, &data, 2); 44 return rc ? 0xffff : data; 45 } 46 static u16 opal_lpc_inw(unsigned long port) 47 { 48 return le16_to_cpu(__opal_lpc_inw(port)); 49 } 50 51 static __le32 __opal_lpc_inl(unsigned long port) 52 { 53 int64_t rc; 54 uint32_t data; 55 56 if (opal_lpc_chip_id < 0 || port > 0xfffc) 57 return 0xffffffff; 58 if (port & 3) 59 return (__le32)opal_lpc_inb(port ) << 24 | 60 (__le32)opal_lpc_inb(port + 1) << 16 | 61 (__le32)opal_lpc_inb(port + 2) << 8 | 62 opal_lpc_inb(port + 3); 63 rc = opal_lpc_read(opal_lpc_chip_id, OPAL_LPC_IO, port, &data, 4); 64 return rc ? 0xffffffff : data; 65 } 66 67 static u32 opal_lpc_inl(unsigned long port) 68 { 69 return le32_to_cpu(__opal_lpc_inl(port)); 70 } 71 72 static void opal_lpc_outb(u8 val, unsigned long port) 73 { 74 if (opal_lpc_chip_id < 0 || port > 0xffff) 75 return; 76 opal_lpc_write(opal_lpc_chip_id, OPAL_LPC_IO, port, val, 1); 77 } 78 79 static void __opal_lpc_outw(__le16 val, unsigned long port) 80 { 81 if (opal_lpc_chip_id < 0 || port > 0xfffe) 82 return; 83 if (port & 1) { 84 opal_lpc_outb(val >> 8, port); 85 opal_lpc_outb(val , port + 1); 86 return; 87 } 88 opal_lpc_write(opal_lpc_chip_id, OPAL_LPC_IO, port, val, 2); 89 } 90 91 static void opal_lpc_outw(u16 val, unsigned long port) 92 { 93 __opal_lpc_outw(cpu_to_le16(val), port); 94 } 95 96 static void __opal_lpc_outl(__le32 val, unsigned long port) 97 { 98 if (opal_lpc_chip_id < 0 || port > 0xfffc) 99 return; 100 if (port & 3) { 101 opal_lpc_outb(val >> 24, port); 102 opal_lpc_outb(val >> 16, port + 1); 103 opal_lpc_outb(val >> 8, port + 2); 104 opal_lpc_outb(val , port + 3); 105 return; 106 } 107 opal_lpc_write(opal_lpc_chip_id, OPAL_LPC_IO, port, val, 4); 108 } 109 110 static void opal_lpc_outl(u32 val, unsigned long port) 111 { 112 __opal_lpc_outl(cpu_to_le32(val), port); 113 } 114 115 static void opal_lpc_insb(unsigned long p, void *b, unsigned long c) 116 { 117 u8 *ptr = b; 118 119 while(c--) 120 *(ptr++) = opal_lpc_inb(p); 121 } 122 123 static void opal_lpc_insw(unsigned long p, void *b, unsigned long c) 124 { 125 __le16 *ptr = b; 126 127 while(c--) 128 *(ptr++) = __opal_lpc_inw(p); 129 } 130 131 static void opal_lpc_insl(unsigned long p, void *b, unsigned long c) 132 { 133 __le32 *ptr = b; 134 135 while(c--) 136 *(ptr++) = __opal_lpc_inl(p); 137 } 138 139 static void opal_lpc_outsb(unsigned long p, const void *b, unsigned long c) 140 { 141 const u8 *ptr = b; 142 143 while(c--) 144 opal_lpc_outb(*(ptr++), p); 145 } 146 147 static void opal_lpc_outsw(unsigned long p, const void *b, unsigned long c) 148 { 149 const __le16 *ptr = b; 150 151 while(c--) 152 __opal_lpc_outw(*(ptr++), p); 153 } 154 155 static void opal_lpc_outsl(unsigned long p, const void *b, unsigned long c) 156 { 157 const __le32 *ptr = b; 158 159 while(c--) 160 __opal_lpc_outl(*(ptr++), p); 161 } 162 163 static const struct ppc_pci_io opal_lpc_io = { 164 .inb = opal_lpc_inb, 165 .inw = opal_lpc_inw, 166 .inl = opal_lpc_inl, 167 .outb = opal_lpc_outb, 168 .outw = opal_lpc_outw, 169 .outl = opal_lpc_outl, 170 .insb = opal_lpc_insb, 171 .insw = opal_lpc_insw, 172 .insl = opal_lpc_insl, 173 .outsb = opal_lpc_outsb, 174 .outsw = opal_lpc_outsw, 175 .outsl = opal_lpc_outsl, 176 }; 177 178 void opal_lpc_init(void) 179 { 180 struct device_node *np; 181 182 /* 183 * Look for a Power8 LPC bus tagged as "primary", 184 * we currently support only one though the OPAL APIs 185 * support any number. 186 */ 187 for_each_compatible_node(np, NULL, "ibm,power8-lpc") { 188 if (!of_device_is_available(np)) 189 continue; 190 if (!of_get_property(np, "primary", NULL)) 191 continue; 192 opal_lpc_chip_id = of_get_ibm_chip_id(np); 193 break; 194 } 195 if (opal_lpc_chip_id < 0) 196 return; 197 198 /* Setup special IO ops */ 199 ppc_pci_io = opal_lpc_io; 200 isa_io_special = true; 201 202 pr_info("OPAL: Power8 LPC bus found, chip ID %d\n", opal_lpc_chip_id); 203 } 204