/* * Device driver for the via-cuda on Apple Powermacs. * * The VIA (versatile interface adapter) interfaces to the CUDA, * a 6805 microprocessor core which controls the ADB (Apple Desktop * Bus) which connects to the keyboard and mouse. The CUDA also * controls system power and the RTC (real time clock) chip. * * Copyright (C) 1996 Paul Mackerras. */ #include <stdarg.h> #include <linux/types.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/delay.h> #include <linux/adb.h> #include <linux/cuda.h> #include <linux/spinlock.h> #include <linux/interrupt.h> #ifdef CONFIG_PPC #include <asm/prom.h> #include <asm/machdep.h> #else #include <asm/macintosh.h> #include <asm/macints.h> #include <asm/mac_via.h> #endif #include <asm/io.h> #include <linux/init.h> static volatile unsigned char __iomem *via; static DEFINE_SPINLOCK(cuda_lock); /* VIA registers - spaced 0x200 bytes apart */ #define RS 0x200 /* skip between registers */ #define B 0 /* B-side data */ #define A RS /* A-side data */ #define DIRB (2*RS) /* B-side direction (1=output) */ #define DIRA (3*RS) /* A-side direction (1=output) */ #define T1CL (4*RS) /* Timer 1 ctr/latch (low 8 bits) */ #define T1CH (5*RS) /* Timer 1 counter (high 8 bits) */ #define T1LL (6*RS) /* Timer 1 latch (low 8 bits) */ #define T1LH (7*RS) /* Timer 1 latch (high 8 bits) */ #define T2CL (8*RS) /* Timer 2 ctr/latch (low 8 bits) */ #define T2CH (9*RS) /* Timer 2 counter (high 8 bits) */ #define SR (10*RS) /* Shift register */ #define ACR (11*RS) /* Auxiliary control register */ #define PCR (12*RS) /* Peripheral control register */ #define IFR (13*RS) /* Interrupt flag register */ #define IER (14*RS) /* Interrupt enable register */ #define ANH (15*RS) /* A-side data, no handshake */ /* Bits in B data register: all active low */ #define TREQ 0x08 /* Transfer request (input) */ #define TACK 0x10 /* Transfer acknowledge (output) */ #define TIP 0x20 /* Transfer in progress (output) */ /* Bits in ACR */ #define SR_CTRL 0x1c /* Shift register control bits */ #define SR_EXT 0x0c /* Shift on external clock */ #define SR_OUT 0x10 /* Shift out if 1 */ /* Bits in IFR and IER */ #define IER_SET 0x80 /* set bits in IER */ #define IER_CLR 0 /* clear bits in IER */ #define SR_INT 0x04 /* Shift register full/empty */ static enum cuda_state { idle, sent_first_byte, sending, reading, read_done, awaiting_reply } cuda_state; static struct adb_request *current_req; static struct adb_request *last_req; static unsigned char cuda_rbuf[16]; static unsigned char *reply_ptr; static int reading_reply; static int data_index; static int cuda_irq; #ifdef CONFIG_PPC static struct device_node *vias; #endif static int cuda_fully_inited; #ifdef CONFIG_ADB static int cuda_probe(void); static int cuda_send_request(struct adb_request *req, int sync); static int cuda_adb_autopoll(int devs); static int cuda_reset_adb_bus(void); #endif /* CONFIG_ADB */ static int cuda_init_via(void); static void cuda_start(void); static irqreturn_t cuda_interrupt(int irq, void *arg); static void cuda_input(unsigned char *buf, int nb); void cuda_poll(void); static int cuda_write(struct adb_request *req); int cuda_request(struct adb_request *req, void (*done)(struct adb_request *), int nbytes, ...); #ifdef CONFIG_ADB struct adb_driver via_cuda_driver = { .name = "CUDA", .probe = cuda_probe, .send_request = cuda_send_request, .autopoll = cuda_adb_autopoll, .poll = cuda_poll, .reset_bus = cuda_reset_adb_bus, }; #endif /* CONFIG_ADB */ #ifdef CONFIG_MAC int __init find_via_cuda(void) { struct adb_request req; int err; if (macintosh_config->adb_type != MAC_ADB_CUDA) return 0; via = via1; cuda_state = idle; err = cuda_init_via(); if (err) { printk(KERN_ERR "cuda_init_via() failed\n"); via = NULL; return 0; } /* enable autopoll */ cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1); while (!req.complete) cuda_poll(); return 1; } #else int __init find_via_cuda(void) { struct adb_request req; phys_addr_t taddr; const u32 *reg; int err; if (vias != 0) return 1; vias = of_find_node_by_name(NULL, "via-cuda"); if (vias == 0) return 0; reg = of_get_property(vias, "reg", NULL); if (reg == NULL) { printk(KERN_ERR "via-cuda: No \"reg\" property !\n"); goto fail; } taddr = of_translate_address(vias, reg); if (taddr == 0) { printk(KERN_ERR "via-cuda: Can't translate address !\n"); goto fail; } via = ioremap(taddr, 0x2000); if (via == NULL) { printk(KERN_ERR "via-cuda: Can't map address !\n"); goto fail; } cuda_state = idle; sys_ctrler = SYS_CTRLER_CUDA; err = cuda_init_via(); if (err) { printk(KERN_ERR "cuda_init_via() failed\n"); via = NULL; return 0; } /* Clear and enable interrupts, but only on PPC. On 68K it's done */ /* for us by the main VIA driver in arch/m68k/mac/via.c */ out_8(&via[IFR], 0x7f); /* clear interrupts by writing 1s */ out_8(&via[IER], IER_SET|SR_INT); /* enable interrupt from SR */ /* enable autopoll */ cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1); while (!req.complete) cuda_poll(); return 1; fail: of_node_put(vias); vias = NULL; return 0; } #endif /* !defined CONFIG_MAC */ static int __init via_cuda_start(void) { if (via == NULL) return -ENODEV; #ifdef CONFIG_MAC cuda_irq = IRQ_MAC_ADB; #else cuda_irq = irq_of_parse_and_map(vias, 0); if (cuda_irq == NO_IRQ) { printk(KERN_ERR "via-cuda: can't map interrupts for %s\n", vias->full_name); return -ENODEV; } #endif if (request_irq(cuda_irq, cuda_interrupt, 0, "ADB", cuda_interrupt)) { printk(KERN_ERR "via-cuda: can't request irq %d\n", cuda_irq); return -EAGAIN; } printk("Macintosh CUDA driver v0.5 for Unified ADB.\n"); cuda_fully_inited = 1; return 0; } device_initcall(via_cuda_start); #ifdef CONFIG_ADB static int cuda_probe(void) { #ifdef CONFIG_PPC if (sys_ctrler != SYS_CTRLER_CUDA) return -ENODEV; #else if (macintosh_config->adb_type != MAC_ADB_CUDA) return -ENODEV; #endif if (via == NULL) return -ENODEV; return 0; } #endif /* CONFIG_ADB */ #define WAIT_FOR(cond, what) \ do { \ int x; \ for (x = 1000; !(cond); --x) { \ if (x == 0) { \ printk("Timeout waiting for " what "\n"); \ return -ENXIO; \ } \ udelay(100); \ } \ } while (0) static int __init cuda_init_via(void) { out_8(&via[DIRB], (in_8(&via[DIRB]) | TACK | TIP) & ~TREQ); /* TACK & TIP out */ out_8(&via[B], in_8(&via[B]) | TACK | TIP); /* negate them */ out_8(&via[ACR] ,(in_8(&via[ACR]) & ~SR_CTRL) | SR_EXT); /* SR data in */ (void)in_8(&via[SR]); /* clear any left-over data */ #ifdef CONFIG_PPC out_8(&via[IER], 0x7f); /* disable interrupts from VIA */ (void)in_8(&via[IER]); #else out_8(&via[IER], SR_INT); /* disable SR interrupt from VIA */ #endif /* delay 4ms and then clear any pending interrupt */ mdelay(4); (void)in_8(&via[SR]); out_8(&via[IFR], SR_INT); /* sync with the CUDA - assert TACK without TIP */ out_8(&via[B], in_8(&via[B]) & ~TACK); /* wait for the CUDA to assert TREQ in response */ WAIT_FOR((in_8(&via[B]) & TREQ) == 0, "CUDA response to sync"); /* wait for the interrupt and then clear it */ WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (2)"); (void)in_8(&via[SR]); out_8(&via[IFR], SR_INT); /* finish the sync by negating TACK */ out_8(&via[B], in_8(&via[B]) | TACK); /* wait for the CUDA to negate TREQ and the corresponding interrupt */ WAIT_FOR(in_8(&via[B]) & TREQ, "CUDA response to sync (3)"); WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (4)"); (void)in_8(&via[SR]); out_8(&via[IFR], SR_INT); out_8(&via[B], in_8(&via[B]) | TIP); /* should be unnecessary */ return 0; } #ifdef CONFIG_ADB /* Send an ADB command */ static int cuda_send_request(struct adb_request *req, int sync) { int i; if ((via == NULL) || !cuda_fully_inited) { req->complete = 1; return -ENXIO; } req->reply_expected = 1; i = cuda_write(req); if (i) return i; if (sync) { while (!req->complete) cuda_poll(); } return 0; } /* Enable/disable autopolling */ static int cuda_adb_autopoll(int devs) { struct adb_request req; if ((via == NULL) || !cuda_fully_inited) return -ENXIO; cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, (devs? 1: 0)); while (!req.complete) cuda_poll(); return 0; } /* Reset adb bus - how do we do this?? */ static int cuda_reset_adb_bus(void) { struct adb_request req; if ((via == NULL) || !cuda_fully_inited) return -ENXIO; cuda_request(&req, NULL, 2, ADB_PACKET, 0); /* maybe? */ while (!req.complete) cuda_poll(); return 0; } #endif /* CONFIG_ADB */ /* Construct and send a cuda request */ int cuda_request(struct adb_request *req, void (*done)(struct adb_request *), int nbytes, ...) { va_list list; int i; if (via == NULL) { req->complete = 1; return -ENXIO; } req->nbytes = nbytes; req->done = done; va_start(list, nbytes); for (i = 0; i < nbytes; ++i) req->data[i] = va_arg(list, int); va_end(list); req->reply_expected = 1; return cuda_write(req); } static int cuda_write(struct adb_request *req) { unsigned long flags; if (req->nbytes < 2 || req->data[0] > CUDA_PACKET) { req->complete = 1; return -EINVAL; } req->next = NULL; req->sent = 0; req->complete = 0; req->reply_len = 0; spin_lock_irqsave(&cuda_lock, flags); if (current_req != 0) { last_req->next = req; last_req = req; } else { current_req = req; last_req = req; if (cuda_state == idle) cuda_start(); } spin_unlock_irqrestore(&cuda_lock, flags); return 0; } static void cuda_start(void) { struct adb_request *req; /* assert cuda_state == idle */ /* get the packet to send */ req = current_req; if (req == 0) return; if ((in_8(&via[B]) & TREQ) == 0) return; /* a byte is coming in from the CUDA */ /* set the shift register to shift out and send a byte */ out_8(&via[ACR], in_8(&via[ACR]) | SR_OUT); out_8(&via[SR], req->data[0]); out_8(&via[B], in_8(&via[B]) & ~TIP); cuda_state = sent_first_byte; } void cuda_poll(void) { /* cuda_interrupt only takes a normal lock, we disable * interrupts here to avoid re-entering and thus deadlocking. */ if (cuda_irq) disable_irq(cuda_irq); cuda_interrupt(0, NULL); if (cuda_irq) enable_irq(cuda_irq); } static irqreturn_t cuda_interrupt(int irq, void *arg) { int status; struct adb_request *req = NULL; unsigned char ibuf[16]; int ibuf_len = 0; int complete = 0; spin_lock(&cuda_lock); /* On powermacs, this handler is registered for the VIA IRQ. But they use * just the shift register IRQ -- other VIA interrupt sources are disabled. * On m68k macs, the VIA IRQ sources are dispatched individually. Unless * we are polling, the shift register IRQ flag has already been cleared. */ #ifdef CONFIG_MAC if (!arg) #endif { if ((in_8(&via[IFR]) & SR_INT) == 0) { spin_unlock(&cuda_lock); return IRQ_NONE; } else { out_8(&via[IFR], SR_INT); } } status = (~in_8(&via[B]) & (TIP|TREQ)) | (in_8(&via[ACR]) & SR_OUT); /* printk("cuda_interrupt: state=%d status=%x\n", cuda_state, status); */ switch (cuda_state) { case idle: /* CUDA has sent us the first byte of data - unsolicited */ if (status != TREQ) printk("cuda: state=idle, status=%x\n", status); (void)in_8(&via[SR]); out_8(&via[B], in_8(&via[B]) & ~TIP); cuda_state = reading; reply_ptr = cuda_rbuf; reading_reply = 0; break; case awaiting_reply: /* CUDA has sent us the first byte of data of a reply */ if (status != TREQ) printk("cuda: state=awaiting_reply, status=%x\n", status); (void)in_8(&via[SR]); out_8(&via[B], in_8(&via[B]) & ~TIP); cuda_state = reading; reply_ptr = current_req->reply; reading_reply = 1; break; case sent_first_byte: if (status == TREQ + TIP + SR_OUT) { /* collision */ out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT); (void)in_8(&via[SR]); out_8(&via[B], in_8(&via[B]) | TIP | TACK); cuda_state = idle; } else { /* assert status == TIP + SR_OUT */ if (status != TIP + SR_OUT) printk("cuda: state=sent_first_byte status=%x\n", status); out_8(&via[SR], current_req->data[1]); out_8(&via[B], in_8(&via[B]) ^ TACK); data_index = 2; cuda_state = sending; } break; case sending: req = current_req; if (data_index >= req->nbytes) { out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT); (void)in_8(&via[SR]); out_8(&via[B], in_8(&via[B]) | TACK | TIP); req->sent = 1; if (req->reply_expected) { cuda_state = awaiting_reply; } else { current_req = req->next; complete = 1; /* not sure about this */ cuda_state = idle; cuda_start(); } } else { out_8(&via[SR], req->data[data_index++]); out_8(&via[B], in_8(&via[B]) ^ TACK); } break; case reading: *reply_ptr++ = in_8(&via[SR]); if (status == TIP) { /* that's all folks */ out_8(&via[B], in_8(&via[B]) | TACK | TIP); cuda_state = read_done; } else { /* assert status == TIP | TREQ */ if (status != TIP + TREQ) printk("cuda: state=reading status=%x\n", status); out_8(&via[B], in_8(&via[B]) ^ TACK); } break; case read_done: (void)in_8(&via[SR]); if (reading_reply) { req = current_req; req->reply_len = reply_ptr - req->reply; if (req->data[0] == ADB_PACKET) { /* Have to adjust the reply from ADB commands */ if (req->reply_len <= 2 || (req->reply[1] & 2) != 0) { /* the 0x2 bit indicates no response */ req->reply_len = 0; } else { /* leave just the command and result bytes in the reply */ req->reply_len -= 2; memmove(req->reply, req->reply + 2, req->reply_len); } } current_req = req->next; complete = 1; } else { /* This is tricky. We must break the spinlock to call * cuda_input. However, doing so means we might get * re-entered from another CPU getting an interrupt * or calling cuda_poll(). I ended up using the stack * (it's only for 16 bytes) and moving the actual * call to cuda_input to outside of the lock. */ ibuf_len = reply_ptr - cuda_rbuf; memcpy(ibuf, cuda_rbuf, ibuf_len); } if (status == TREQ) { out_8(&via[B], in_8(&via[B]) & ~TIP); cuda_state = reading; reply_ptr = cuda_rbuf; reading_reply = 0; } else { cuda_state = idle; cuda_start(); } break; default: printk("cuda_interrupt: unknown cuda_state %d?\n", cuda_state); } spin_unlock(&cuda_lock); if (complete && req) { void (*done)(struct adb_request *) = req->done; mb(); req->complete = 1; /* Here, we assume that if the request has a done member, the * struct request will survive to setting req->complete to 1 */ if (done) (*done)(req); } if (ibuf_len) cuda_input(ibuf, ibuf_len); return IRQ_HANDLED; } static void cuda_input(unsigned char *buf, int nb) { int i; switch (buf[0]) { case ADB_PACKET: #ifdef CONFIG_XMON if (nb == 5 && buf[2] == 0x2c) { extern int xmon_wants_key, xmon_adb_keycode; if (xmon_wants_key) { xmon_adb_keycode = buf[3]; return; } } #endif /* CONFIG_XMON */ #ifdef CONFIG_ADB adb_input(buf+2, nb-2, buf[1] & 0x40); #endif /* CONFIG_ADB */ break; default: printk("data from cuda (%d bytes):", nb); for (i = 0; i < nb; ++i) printk(" %.2x", buf[i]); printk("\n"); } }