/* * Apple Peripheral System Controller (PSC) * * The PSC is used on the AV Macs to control IO functions not handled * by the VIAs (Ethernet, DSP, SCC). * * TO DO: * * Try to figure out what's going on in pIFR5 and pIFR6. There seem to be * persisant interrupt conditions in those registers and I have no idea what * they are. Granted it doesn't affect since we're not enabling any interrupts * on those levels at the moment, but it would be nice to know. I have a feeling * they aren't actually interrupt lines but data lines (to the DSP?) */ #include <linux/types.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/delay.h> #include <linux/init.h> #include <linux/irq.h> #include <asm/traps.h> #include <asm/bootinfo.h> #include <asm/macintosh.h> #include <asm/macints.h> #include <asm/mac_psc.h> #define DEBUG_PSC int psc_present; volatile __u8 *psc; /* * Debugging dump, used in various places to see what's going on. */ static void psc_debug_dump(void) { int i; if (!psc_present) return; for (i = 0x30 ; i < 0x70 ; i += 0x10) { printk("PSC #%d: IFR = 0x%02X IER = 0x%02X\n", i >> 4, (int) psc_read_byte(pIFRbase + i), (int) psc_read_byte(pIERbase + i)); } } /* * Try to kill all DMA channels on the PSC. Not sure how this his * supposed to work; this is code lifted from macmace.c and then * expanded to cover what I think are the other 7 channels. */ static void psc_dma_die_die_die(void) { int i; printk("Killing all PSC DMA channels..."); for (i = 0 ; i < 9 ; i++) { psc_write_word(PSC_CTL_BASE + (i << 4), 0x8800); psc_write_word(PSC_CTL_BASE + (i << 4), 0x1000); psc_write_word(PSC_CMD_BASE + (i << 5), 0x1100); psc_write_word(PSC_CMD_BASE + (i << 5) + 0x10, 0x1100); } printk("done!\n"); } /* * Initialize the PSC. For now this just involves shutting down all * interrupt sources using the IERs. */ void __init psc_init(void) { int i; if (macintosh_config->ident != MAC_MODEL_C660 && macintosh_config->ident != MAC_MODEL_Q840) { psc = NULL; psc_present = 0; return; } /* * The PSC is always at the same spot, but using psc * keeps things consistent with the psc_xxxx functions. */ psc = (void *) PSC_BASE; psc_present = 1; printk("PSC detected at %p\n", psc); psc_dma_die_die_die(); #ifdef DEBUG_PSC psc_debug_dump(); #endif /* * Mask and clear all possible interrupts */ for (i = 0x30 ; i < 0x70 ; i += 0x10) { psc_write_byte(pIERbase + i, 0x0F); psc_write_byte(pIFRbase + i, 0x0F); } } /* * PSC interrupt handler. It's a lot like the VIA interrupt handler. */ static void psc_irq(unsigned int irq, struct irq_desc *desc) { unsigned int offset = (unsigned int)irq_desc_get_handler_data(desc); int pIFR = pIFRbase + offset; int pIER = pIERbase + offset; int irq_num; unsigned char irq_bit, events; #ifdef DEBUG_IRQS printk("psc_irq: irq %u pIFR = 0x%02X pIER = 0x%02X\n", irq, (int) psc_read_byte(pIFR), (int) psc_read_byte(pIER)); #endif events = psc_read_byte(pIFR) & psc_read_byte(pIER) & 0xF; if (!events) return; irq_num = irq << 3; irq_bit = 1; do { if (events & irq_bit) { psc_write_byte(pIFR, irq_bit); generic_handle_irq(irq_num); } irq_num++; irq_bit <<= 1; } while (events >= irq_bit); } /* * Register the PSC interrupt dispatchers for autovector interrupts 3-6. */ void __init psc_register_interrupts(void) { irq_set_chained_handler(IRQ_AUTO_3, psc_irq); irq_set_handler_data(IRQ_AUTO_3, (void *)0x30); irq_set_chained_handler(IRQ_AUTO_4, psc_irq); irq_set_handler_data(IRQ_AUTO_4, (void *)0x40); irq_set_chained_handler(IRQ_AUTO_5, psc_irq); irq_set_handler_data(IRQ_AUTO_5, (void *)0x50); irq_set_chained_handler(IRQ_AUTO_6, psc_irq); irq_set_handler_data(IRQ_AUTO_6, (void *)0x60); } void psc_irq_enable(int irq) { int irq_src = IRQ_SRC(irq); int irq_idx = IRQ_IDX(irq); int pIER = pIERbase + (irq_src << 4); #ifdef DEBUG_IRQUSE printk("psc_irq_enable(%d)\n", irq); #endif psc_write_byte(pIER, (1 << irq_idx) | 0x80); } void psc_irq_disable(int irq) { int irq_src = IRQ_SRC(irq); int irq_idx = IRQ_IDX(irq); int pIER = pIERbase + (irq_src << 4); #ifdef DEBUG_IRQUSE printk("psc_irq_disable(%d)\n", irq); #endif psc_write_byte(pIER, 1 << irq_idx); }