2  * I/O Processor (IOP) management
16  * The IOP chips are used in the IIfx and some Quadras (900, 950) to manage
19  * 990429 (jmt) - Initial implementation, just enough to knock the SCC IOP
22  * 990603 (jmt) - Added code to grab the correct ISM IOP interrupt for OSS
26  * 990605 (jmt) - Rearranged things a bit wrt IOP detection; iop_present is
27  *		  gone, IOP base addresses are now in an array and the
28  *		  globally-visible functions take an IOP number instead of an
33  *		  IOP. The trick now is figuring out the message formats.
41  *		  unsolicited messages from the IOP (and our replies to them
45  * 990729 (jmt) - Added passing of pt_regs structure to IOP handlers. This is
51  *   IOP hasn't died.
52  * o Some of the IOP manager routines need better error checking and
58  * IOP Message Passing 101
62  * a shared memory area in the IOP RAM. Each IOP has seven "channels"; each
63  * channel is connected to a specific software driver on the IOP. For example
64  * on the SCC IOP there is one channel for each serial port. Each channel has
69  * buffer, set the state to MSG_NEW and signal the IOP by setting the IRQ flag
70  * in the IOP control to 1. The IOP will move the state to MSG_RCVD when it
76  * To receive message from the IOP the same procedure is used except the roles
77  * are reversed. That is, the IOP puts message in the channel with a state of
80  * has been placed back in the receive channel. The IOP will then reset the
84  * interrupt level; they are distinguished by a pair of bits in the IOP status
85  * register. The IOP will raise INT0 when one or more messages in the send
96  * a message is received on that IOP/channel combination. The handlers are
98  * from the IOP. The message state will be in MSG_RCVD while the handler runs;
101  * the IOP. This two-step process is provided to allow the handler to defer
142  * IOP structures for the two IOPs
144  * The SCC IOP controls both serial ports (A and B) as its two functions.
145  * The ISM IOP controls the SWIM (floppy drive) and ADB.
151  * IOP message queues
164 static __inline__ void iop_loadaddr(volatile struct mac_iop *iop, __u16 addr)  in iop_loadaddr()  argument
166 	iop->ram_addr_lo = addr;  in iop_loadaddr()
167 	iop->ram_addr_hi = addr >> 8;  in iop_loadaddr()
170 static __inline__ __u8 iop_readb(volatile struct mac_iop *iop, __u16 addr)  in iop_readb()  argument
172 	iop->ram_addr_lo = addr;  in iop_readb()
173 	iop->ram_addr_hi = addr >> 8;  in iop_readb()
174 	return iop->ram_data;  in iop_readb()
177 static __inline__ void iop_writeb(volatile struct mac_iop *iop, __u16 addr, __u8 data)  in iop_writeb()  argument
179 	iop->ram_addr_lo = addr;  in iop_writeb()
180 	iop->ram_addr_hi = addr >> 8;  in iop_writeb()
181 	iop->ram_data = data;  in iop_writeb()
184 static __inline__ void iop_stop(volatile struct mac_iop *iop)  in iop_stop()  argument
186 	iop->status_ctrl = IOP_AUTOINC;  in iop_stop()
189 static __inline__ void iop_start(volatile struct mac_iop *iop)  in iop_start()  argument
191 	iop->status_ctrl = IOP_RUN | IOP_AUTOINC;  in iop_start()
194 static __inline__ void iop_interrupt(volatile struct mac_iop *iop)  in iop_interrupt()  argument
196 	iop->status_ctrl = IOP_IRQ | IOP_RUN | IOP_AUTOINC;  in iop_interrupt()
199 static int iop_alive(volatile struct mac_iop *iop)  in iop_alive()  argument
203 	retval = (iop_readb(iop, IOP_ADDR_ALIVE) == 0xFF);  in iop_alive()
204 	iop_writeb(iop, IOP_ADDR_ALIVE, 0);  in iop_alive()
230  * the serial IOP can be placed into bypass mode _before_ we try to
270 		pr_debug("SCC IOP detected at %p\n", iop_base[IOP_NUM_SCC]);  in iop_init()
273 		pr_debug("ISM IOP detected at %p\n", iop_base[IOP_NUM_ISM]);  in iop_init()
303 					"ISM IOP", (void *)IOP_NUM_ISM))  in iop_register_interrupts()
304 				pr_err("Couldn't register ISM IOP interrupt\n");  in iop_register_interrupts()
306 			if (request_irq(IRQ_VIA2_0, iop_ism_irq, 0, "ISM IOP",  in iop_register_interrupts()
308 				pr_err("Couldn't register ISM IOP interrupt\n");  in iop_register_interrupts()
311 			pr_warn("IOP: oh my god, they killed the ISM IOP!\n");  in iop_register_interrupts()
313 			pr_warn("IOP: the ISM IOP seems to be alive.\n");  in iop_register_interrupts()
319  * Register or unregister a listener for a specific IOP and channel
341  * notifying the IOP.
372 	volatile struct mac_iop *iop = iop_base[msg->iop_num];  in iop_do_send()  local
381 		iop_writeb(iop, offset, msg->message[i]);  in iop_do_send()
384 	iop_writeb(iop, IOP_ADDR_SEND_STATE + msg->channel, IOP_MSG_NEW);  in iop_do_send()
386 	iop_interrupt(iop);  in iop_do_send()
396 	volatile struct mac_iop *iop = iop_base[iop_num];  in iop_handle_send()  local
400 	iop_writeb(iop, IOP_ADDR_SEND_STATE + chan, IOP_MSG_IDLE);  in iop_handle_send()
407 		msg->reply[i] = iop_readb(iop, offset);  in iop_handle_send()
416 	if (msg && iop_readb(iop, IOP_ADDR_SEND_STATE + chan) == IOP_MSG_IDLE)  in iop_handle_send()
427 	volatile struct mac_iop *iop = iop_base[iop_num];  in iop_handle_recv()  local
440 		msg->message[i] = iop_readb(iop, offset);  in iop_handle_recv()
445 	iop_writeb(iop, IOP_ADDR_RECV_STATE + chan, IOP_MSG_RCVD);  in iop_handle_recv()
499  * Upload code to the shared RAM of an IOP.
515  * Download code from the shared RAM of an IOP.
531  * Compare the code in the shared RAM of an IOP with a copy in system memory
553  * Handle an ISM IOP interrupt
559 	volatile struct mac_iop *iop = iop_base[iop_num];  in iop_ism_irq()  local
561 	u8 events = iop->status_ctrl & (IOP_INT0 | IOP_INT1);  in iop_ism_irq()
565 			     iop->status_ctrl);  in iop_ism_irq()
569 			iop->status_ctrl = IOP_INT0 | IOP_RUN | IOP_AUTOINC;  in iop_ism_irq()
571 				state = iop_readb(iop, IOP_ADDR_SEND_STATE + i);  in iop_ism_irq()
582 			iop->status_ctrl = IOP_INT1 | IOP_RUN | IOP_AUTOINC;  in iop_ism_irq()
584 				state = iop_readb(iop, IOP_ADDR_RECV_STATE + i);  in iop_ism_irq()
593 		events = iop->status_ctrl & (IOP_INT0 | IOP_INT1);  in iop_ism_irq()