1 /* 2 * Basic EISA bus support for the SGI Indigo-2. 3 * 4 * (C) 2002 Pascal Dameme <netinet@freesurf.fr> 5 * and Marc Zyngier <mzyngier@freesurf.fr> 6 * 7 * This code is released under both the GPL version 2 and BSD 8 * licenses. Either license may be used. 9 * 10 * This code offers a very basic support for this EISA bus present in 11 * the SGI Indigo-2. It currently only supports PIO (forget about DMA 12 * for the time being). This is enough for a low-end ethernet card, 13 * but forget about your favorite SCSI card... 14 * 15 * TODO : 16 * - Fix bugs... 17 * - Add ISA support 18 * - Add DMA (yeah, right...). 19 * - Fix more bugs. 20 */ 21 22 #include <linux/eisa.h> 23 #include <linux/types.h> 24 #include <linux/init.h> 25 #include <linux/irq.h> 26 #include <linux/kernel_stat.h> 27 #include <linux/signal.h> 28 #include <linux/sched.h> 29 #include <linux/interrupt.h> 30 #include <linux/delay.h> 31 #include <asm/io.h> 32 #include <asm/irq.h> 33 #include <asm/mipsregs.h> 34 #include <asm/addrspace.h> 35 #include <asm/processor.h> 36 #include <asm/sgi/ioc.h> 37 #include <asm/sgi/mc.h> 38 #include <asm/sgi/ip22.h> 39 40 /* I2 has four EISA slots. */ 41 #define IP22_EISA_MAX_SLOTS 4 42 #define EISA_MAX_IRQ 16 43 44 #define EIU_MODE_REG 0x0001ffc0 45 #define EIU_STAT_REG 0x0001ffc4 46 #define EIU_PREMPT_REG 0x0001ffc8 47 #define EIU_QUIET_REG 0x0001ffcc 48 #define EIU_INTRPT_ACK 0x00010004 49 50 static char __init *decode_eisa_sig(unsigned long addr) 51 { 52 static char sig_str[EISA_SIG_LEN]; 53 u8 sig[4]; 54 u16 rev; 55 int i; 56 57 for (i = 0; i < 4; i++) { 58 sig[i] = inb(addr + i); 59 60 if (!i && (sig[0] & 0x80)) 61 return NULL; 62 } 63 64 sig_str[0] = ((sig[0] >> 2) & 0x1f) + ('A' - 1); 65 sig_str[1] = (((sig[0] & 3) << 3) | (sig[1] >> 5)) + ('A' - 1); 66 sig_str[2] = (sig[1] & 0x1f) + ('A' - 1); 67 rev = (sig[2] << 8) | sig[3]; 68 sprintf(sig_str + 3, "%04X", rev); 69 70 return sig_str; 71 } 72 73 static irqreturn_t ip22_eisa_intr(int irq, void *dev_id) 74 { 75 u8 eisa_irq; 76 u8 dma1, dma2; 77 78 eisa_irq = inb(EIU_INTRPT_ACK); 79 dma1 = inb(EISA_DMA1_STATUS); 80 dma2 = inb(EISA_DMA2_STATUS); 81 82 if (eisa_irq < EISA_MAX_IRQ) { 83 do_IRQ(eisa_irq); 84 return IRQ_HANDLED; 85 } 86 87 /* Oops, Bad Stuff Happened... */ 88 printk(KERN_ERR "eisa_irq %d out of bound\n", eisa_irq); 89 90 outb(0x20, EISA_INT2_CTRL); 91 outb(0x20, EISA_INT1_CTRL); 92 93 return IRQ_NONE; 94 } 95 96 static void enable_eisa1_irq(unsigned int irq) 97 { 98 u8 mask; 99 100 mask = inb(EISA_INT1_MASK); 101 mask &= ~((u8) (1 << irq)); 102 outb(mask, EISA_INT1_MASK); 103 } 104 105 static unsigned int startup_eisa1_irq(unsigned int irq) 106 { 107 u8 edge; 108 109 /* Only use edge interrupts for EISA */ 110 111 edge = inb(EISA_INT1_EDGE_LEVEL); 112 edge &= ~((u8) (1 << irq)); 113 outb(edge, EISA_INT1_EDGE_LEVEL); 114 115 enable_eisa1_irq(irq); 116 return 0; 117 } 118 119 static void disable_eisa1_irq(unsigned int irq) 120 { 121 u8 mask; 122 123 mask = inb(EISA_INT1_MASK); 124 mask |= ((u8) (1 << irq)); 125 outb(mask, EISA_INT1_MASK); 126 } 127 128 static void mask_and_ack_eisa1_irq(unsigned int irq) 129 { 130 disable_eisa1_irq(irq); 131 132 outb(0x20, EISA_INT1_CTRL); 133 } 134 135 static void end_eisa1_irq(unsigned int irq) 136 { 137 if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) 138 enable_eisa1_irq(irq); 139 } 140 141 static struct irq_chip ip22_eisa1_irq_type = { 142 .name = "IP22 EISA", 143 .startup = startup_eisa1_irq, 144 .ack = mask_and_ack_eisa1_irq, 145 .mask = disable_eisa1_irq, 146 .mask_ack = mask_and_ack_eisa1_irq, 147 .unmask = enable_eisa1_irq, 148 .end = end_eisa1_irq, 149 }; 150 151 static void enable_eisa2_irq(unsigned int irq) 152 { 153 u8 mask; 154 155 mask = inb(EISA_INT2_MASK); 156 mask &= ~((u8) (1 << (irq - 8))); 157 outb(mask, EISA_INT2_MASK); 158 } 159 160 static unsigned int startup_eisa2_irq(unsigned int irq) 161 { 162 u8 edge; 163 164 /* Only use edge interrupts for EISA */ 165 166 edge = inb(EISA_INT2_EDGE_LEVEL); 167 edge &= ~((u8) (1 << (irq - 8))); 168 outb(edge, EISA_INT2_EDGE_LEVEL); 169 170 enable_eisa2_irq(irq); 171 return 0; 172 } 173 174 static void disable_eisa2_irq(unsigned int irq) 175 { 176 u8 mask; 177 178 mask = inb(EISA_INT2_MASK); 179 mask |= ((u8) (1 << (irq - 8))); 180 outb(mask, EISA_INT2_MASK); 181 } 182 183 static void mask_and_ack_eisa2_irq(unsigned int irq) 184 { 185 disable_eisa2_irq(irq); 186 187 outb(0x20, EISA_INT2_CTRL); 188 } 189 190 static void end_eisa2_irq(unsigned int irq) 191 { 192 if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) 193 enable_eisa2_irq(irq); 194 } 195 196 static struct irq_chip ip22_eisa2_irq_type = { 197 .name = "IP22 EISA", 198 .startup = startup_eisa2_irq, 199 .ack = mask_and_ack_eisa2_irq, 200 .mask = disable_eisa2_irq, 201 .mask_ack = mask_and_ack_eisa2_irq, 202 .unmask = enable_eisa2_irq, 203 .end = end_eisa2_irq, 204 }; 205 206 static struct irqaction eisa_action = { 207 .handler = ip22_eisa_intr, 208 .name = "EISA", 209 }; 210 211 static struct irqaction cascade_action = { 212 .handler = no_action, 213 .name = "EISA cascade", 214 }; 215 216 int __init ip22_eisa_init(void) 217 { 218 int i, c; 219 char *str; 220 221 if (!(sgimc->systemid & SGIMC_SYSID_EPRESENT)) { 222 printk(KERN_INFO "EISA: bus not present.\n"); 223 return 1; 224 } 225 226 printk(KERN_INFO "EISA: Probing bus...\n"); 227 for (c = 0, i = 1; i <= IP22_EISA_MAX_SLOTS; i++) { 228 if ((str = decode_eisa_sig(0x1000 * i + EISA_VENDOR_ID_OFFSET))) { 229 printk(KERN_INFO "EISA: slot %d : %s detected.\n", 230 i, str); 231 c++; 232 } 233 } 234 printk(KERN_INFO "EISA: Detected %d card%s.\n", c, c < 2 ? "" : "s"); 235 #ifdef CONFIG_ISA 236 printk(KERN_INFO "ISA support compiled in.\n"); 237 #endif 238 239 /* Warning : BlackMagicAhead(tm). 240 Please wave your favorite dead chicken over the busses */ 241 242 /* First say hello to the EIU */ 243 outl(0x0000FFFF, EIU_PREMPT_REG); 244 outl(1, EIU_QUIET_REG); 245 outl(0x40f3c07F, EIU_MODE_REG); 246 247 /* Now be nice to the EISA chipset */ 248 outb(1, EISA_EXT_NMI_RESET_CTRL); 249 udelay(50); /* Wait long enough for the dust to settle */ 250 outb(0, EISA_EXT_NMI_RESET_CTRL); 251 outb(0x11, EISA_INT1_CTRL); 252 outb(0x11, EISA_INT2_CTRL); 253 outb(0, EISA_INT1_MASK); 254 outb(8, EISA_INT2_MASK); 255 outb(4, EISA_INT1_MASK); 256 outb(2, EISA_INT2_MASK); 257 outb(1, EISA_INT1_MASK); 258 outb(1, EISA_INT2_MASK); 259 outb(0xfb, EISA_INT1_MASK); 260 outb(0xff, EISA_INT2_MASK); 261 outb(0, EISA_DMA2_WRITE_SINGLE); 262 263 for (i = SGINT_EISA; i < (SGINT_EISA + EISA_MAX_IRQ); i++) { 264 if (i < (SGINT_EISA + 8)) 265 set_irq_chip(i, &ip22_eisa1_irq_type); 266 else 267 set_irq_chip(i, &ip22_eisa2_irq_type); 268 } 269 270 /* Cannot use request_irq because of kmalloc not being ready at such 271 * an early stage. Yes, I've been bitten... */ 272 setup_irq(SGI_EISA_IRQ, &eisa_action); 273 setup_irq(SGINT_EISA + 2, &cascade_action); 274 275 EISA_bus = 1; 276 return 0; 277 } 278