1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Baboon Custom IC Management 4 * 5 * The Baboon custom IC controls the IDE, PCMCIA and media bay on the 6 * PowerBook 190. It multiplexes multiple interrupt sources onto the 7 * Nubus slot $C interrupt. 8 */ 9 10 #include <linux/types.h> 11 #include <linux/kernel.h> 12 #include <linux/irq.h> 13 14 #include <asm/macintosh.h> 15 #include <asm/macints.h> 16 #include <asm/mac_baboon.h> 17 18 int baboon_present; 19 static volatile struct baboon *baboon; 20 21 /* 22 * Baboon initialization. 23 */ 24 25 void __init baboon_init(void) 26 { 27 if (macintosh_config->ident != MAC_MODEL_PB190) { 28 baboon = NULL; 29 baboon_present = 0; 30 return; 31 } 32 33 baboon = (struct baboon *) BABOON_BASE; 34 baboon_present = 1; 35 36 pr_debug("Baboon detected at %p\n", baboon); 37 } 38 39 /* 40 * Baboon interrupt handler. 41 * XXX how do you clear a pending IRQ? is it even necessary? 42 */ 43 44 static void baboon_irq(struct irq_desc *desc) 45 { 46 short events, irq_bit; 47 int irq_num; 48 49 events = baboon->mb_ifr & 0x07; 50 irq_num = IRQ_BABOON_0; 51 irq_bit = 1; 52 do { 53 if (events & irq_bit) { 54 events &= ~irq_bit; 55 generic_handle_irq(irq_num); 56 } 57 ++irq_num; 58 irq_bit <<= 1; 59 } while (events); 60 } 61 62 /* 63 * Register the Baboon interrupt dispatcher on nubus slot $C. 64 */ 65 66 void __init baboon_register_interrupts(void) 67 { 68 irq_set_chained_handler(IRQ_NUBUS_C, baboon_irq); 69 } 70 71 /* 72 * The means for masking individual Baboon interrupts remains a mystery. 73 * However, since we only use the IDE IRQ, we can just enable/disable all 74 * Baboon interrupts. If/when we handle more than one Baboon IRQ, we must 75 * either figure out how to mask them individually or else implement the 76 * same workaround that's used for NuBus slots (see nubus_disabled and 77 * via_nubus_irq_shutdown). 78 */ 79 80 void baboon_irq_enable(int irq) 81 { 82 mac_irq_enable(irq_get_irq_data(IRQ_NUBUS_C)); 83 } 84 85 void baboon_irq_disable(int irq) 86 { 87 mac_irq_disable(irq_get_irq_data(IRQ_NUBUS_C)); 88 } 89