1 /* 2 * Apple Peripheral System Controller (PSC) 3 * 4 * The PSC is used on the AV Macs to control IO functions not handled 5 * by the VIAs (Ethernet, DSP, SCC). 6 * 7 * TO DO: 8 * 9 * Try to figure out what's going on in pIFR5 and pIFR6. There seem to be 10 * persisant interrupt conditions in those registers and I have no idea what 11 * they are. Granted it doesn't affect since we're not enabling any interrupts 12 * on those levels at the moment, but it would be nice to know. I have a feeling 13 * they aren't actually interrupt lines but data lines (to the DSP?) 14 */ 15 16 #include <linux/types.h> 17 #include <linux/kernel.h> 18 #include <linux/mm.h> 19 #include <linux/delay.h> 20 #include <linux/init.h> 21 22 #include <asm/traps.h> 23 #include <asm/bootinfo.h> 24 #include <asm/macintosh.h> 25 #include <asm/macints.h> 26 #include <asm/mac_psc.h> 27 28 #define DEBUG_PSC 29 30 int psc_present; 31 volatile __u8 *psc; 32 33 irqreturn_t psc_irq(int, void *); 34 35 /* 36 * Debugging dump, used in various places to see what's going on. 37 */ 38 39 static void psc_debug_dump(void) 40 { 41 int i; 42 43 if (!psc_present) return; 44 for (i = 0x30 ; i < 0x70 ; i += 0x10) { 45 printk("PSC #%d: IFR = 0x%02X IER = 0x%02X\n", 46 i >> 4, 47 (int) psc_read_byte(pIFRbase + i), 48 (int) psc_read_byte(pIERbase + i)); 49 } 50 } 51 52 /* 53 * Try to kill all DMA channels on the PSC. Not sure how this his 54 * supposed to work; this is code lifted from macmace.c and then 55 * expanded to cover what I think are the other 7 channels. 56 */ 57 58 static void psc_dma_die_die_die(void) 59 { 60 int i; 61 62 printk("Killing all PSC DMA channels..."); 63 for (i = 0 ; i < 9 ; i++) { 64 psc_write_word(PSC_CTL_BASE + (i << 4), 0x8800); 65 psc_write_word(PSC_CTL_BASE + (i << 4), 0x1000); 66 psc_write_word(PSC_CMD_BASE + (i << 5), 0x1100); 67 psc_write_word(PSC_CMD_BASE + (i << 5) + 0x10, 0x1100); 68 } 69 printk("done!\n"); 70 } 71 72 /* 73 * Initialize the PSC. For now this just involves shutting down all 74 * interrupt sources using the IERs. 75 */ 76 77 void __init psc_init(void) 78 { 79 int i; 80 81 if (macintosh_config->ident != MAC_MODEL_C660 82 && macintosh_config->ident != MAC_MODEL_Q840) 83 { 84 psc = NULL; 85 psc_present = 0; 86 return; 87 } 88 89 /* 90 * The PSC is always at the same spot, but using psc 91 * keeps things consisant with the psc_xxxx functions. 92 */ 93 94 psc = (void *) PSC_BASE; 95 psc_present = 1; 96 97 printk("PSC detected at %p\n", psc); 98 99 psc_dma_die_die_die(); 100 101 #ifdef DEBUG_PSC 102 psc_debug_dump(); 103 #endif 104 /* 105 * Mask and clear all possible interrupts 106 */ 107 108 for (i = 0x30 ; i < 0x70 ; i += 0x10) { 109 psc_write_byte(pIERbase + i, 0x0F); 110 psc_write_byte(pIFRbase + i, 0x0F); 111 } 112 } 113 114 /* 115 * Register the PSC interrupt dispatchers for autovector interrupts 3-6. 116 */ 117 118 void __init psc_register_interrupts(void) 119 { 120 if (request_irq(IRQ_AUTO_3, psc_irq, 0, "psc3", (void *) 0x30)) 121 pr_err("Couldn't register psc%d interrupt\n", 3); 122 if (request_irq(IRQ_AUTO_4, psc_irq, 0, "psc4", (void *) 0x40)) 123 pr_err("Couldn't register psc%d interrupt\n", 4); 124 if (request_irq(IRQ_AUTO_5, psc_irq, 0, "psc5", (void *) 0x50)) 125 pr_err("Couldn't register psc%d interrupt\n", 5); 126 if (request_irq(IRQ_AUTO_6, psc_irq, 0, "psc6", (void *) 0x60)) 127 pr_err("Couldn't register psc%d interrupt\n", 6); 128 } 129 130 /* 131 * PSC interrupt handler. It's a lot like the VIA interrupt handler. 132 */ 133 134 irqreturn_t psc_irq(int irq, void *dev_id) 135 { 136 int pIFR = pIFRbase + ((int) dev_id); 137 int pIER = pIERbase + ((int) dev_id); 138 int irq_num; 139 unsigned char irq_bit, events; 140 141 #ifdef DEBUG_IRQS 142 printk("psc_irq: irq %d pIFR = 0x%02X pIER = 0x%02X\n", 143 irq, (int) psc_read_byte(pIFR), (int) psc_read_byte(pIER)); 144 #endif 145 146 events = psc_read_byte(pIFR) & psc_read_byte(pIER) & 0xF; 147 if (!events) 148 return IRQ_NONE; 149 150 irq_num = irq << 3; 151 irq_bit = 1; 152 do { 153 if (events & irq_bit) { 154 psc_write_byte(pIFR, irq_bit); 155 m68k_handle_int(irq_num); 156 } 157 irq_num++; 158 irq_bit <<= 1; 159 } while (events >= irq_bit); 160 return IRQ_HANDLED; 161 } 162 163 void psc_irq_enable(int irq) { 164 int irq_src = IRQ_SRC(irq); 165 int irq_idx = IRQ_IDX(irq); 166 int pIER = pIERbase + (irq_src << 4); 167 168 #ifdef DEBUG_IRQUSE 169 printk("psc_irq_enable(%d)\n", irq); 170 #endif 171 psc_write_byte(pIER, (1 << irq_idx) | 0x80); 172 } 173 174 void psc_irq_disable(int irq) { 175 int irq_src = IRQ_SRC(irq); 176 int irq_idx = IRQ_IDX(irq); 177 int pIER = pIERbase + (irq_src << 4); 178 179 #ifdef DEBUG_IRQUSE 180 printk("psc_irq_disable(%d)\n", irq); 181 #endif 182 psc_write_byte(pIER, 1 << irq_idx); 183 } 184 185 void psc_irq_clear(int irq) { 186 int irq_src = IRQ_SRC(irq); 187 int irq_idx = IRQ_IDX(irq); 188 int pIFR = pIERbase + (irq_src << 4); 189 190 psc_write_byte(pIFR, 1 << irq_idx); 191 } 192 193 int psc_irq_pending(int irq) 194 { 195 int irq_src = IRQ_SRC(irq); 196 int irq_idx = IRQ_IDX(irq); 197 int pIFR = pIERbase + (irq_src << 4); 198 199 return psc_read_byte(pIFR) & (1 << irq_idx); 200 } 201