yenta.c

讲述linux的初始化过程

}

static unsigned int yenta_events(pci_socket_t *socket)
{
	u8 csc;
	u32 cb_event;
	unsigned int events;

	/* Clear interrupt status for the event */
	cb_event = cb_readl(socket, CB_SOCKET_EVENT);
	cb_writel(socket, CB_SOCKET_EVENT, cb_event);

	csc = exca_readb(socket, I365_CSC);

	events = (cb_event & (CB_CD1EVENT | CB_CD2EVENT)) ? SS_DETECT : 0 ;
	events |= (csc & I365_CSC_DETECT) ? SS_DETECT : 0;
	if (exca_readb(socket, I365_INTCTL) & I365_PC_IOCARD) {
		events |= (csc & I365_CSC_STSCHG) ? SS_STSCHG : 0;
	} else {
		events |= (csc & I365_CSC_BVD1) ? SS_BATDEAD : 0;
		events |= (csc & I365_CSC_BVD2) ? SS_BATWARN : 0;
		events |= (csc & I365_CSC_READY) ? SS_READY : 0;
	}
	return events;
}


static void yenta_bh(void *data)
{
	pci_socket_t *socket = data;
	unsigned int events;

	spin_lock_irq(&socket->event_lock);
	events = socket->events;
	socket->events = 0;
	spin_unlock_irq(&socket->event_lock);
	if (socket->handler)
		socket->handler(socket->info, events);
}

static void yenta_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	unsigned int events;
	pci_socket_t *socket = (pci_socket_t *) dev_id;

	events = yenta_events(socket);
	if (events) {
		spin_lock(&socket->event_lock);
		socket->events |= events;
		spin_unlock(&socket->event_lock);
		schedule_task(&socket->tq_task);
	}
}

static void yenta_interrupt_wrapper(unsigned long data)
{
	pci_socket_t *socket = (pci_socket_t *) data;

	yenta_interrupt(0, (void *)socket, NULL);
	socket->poll_timer.expires = jiffies + HZ;
	add_timer(&socket->poll_timer);
}

/*
 * Only probe "regular" interrupts, don't
 * touch dangerous spots like the mouse irq,
 * because there are mice that apparently
 * get really confused if they get fondled
 * too intimately.
 *
 * Default to 11, 10, 9, 7, 6, 5, 4, 3.
 */
static u32 isa_interrupts = 0x0ef8;

static unsigned int yenta_probe_irq(pci_socket_t *socket, u32 isa_irq_mask)
{
	int i;
	unsigned long val;
	u16 bridge_ctrl;
	u32 mask;

	/* Set up ISA irq routing to probe the ISA irqs.. */
	bridge_ctrl = config_readw(socket, CB_BRIDGE_CONTROL);
	if (!(bridge_ctrl & CB_BRIDGE_INTR)) {
		bridge_ctrl |= CB_BRIDGE_INTR;
		config_writew(socket, CB_BRIDGE_CONTROL, bridge_ctrl);
	}

	/*
	 * Probe for usable interrupts using the force
	 * register to generate bogus card status events.
	 */
	cb_writel(socket, CB_SOCKET_EVENT, -1);
	cb_writel(socket, CB_SOCKET_MASK, CB_CSTSMASK);
	exca_writeb(socket, I365_CSCINT, 0);
	val = probe_irq_on() & isa_irq_mask;
	for (i = 1; i < 16; i++) {
		if (!((val >> i) & 1))
			continue;
		exca_writeb(socket, I365_CSCINT, I365_CSC_STSCHG | (i << 4));
		cb_writel(socket, CB_SOCKET_FORCE, CB_FCARDSTS);
		udelay(100);
		cb_writel(socket, CB_SOCKET_EVENT, -1);
	}
	cb_writel(socket, CB_SOCKET_MASK, 0);
	exca_writeb(socket, I365_CSCINT, 0);
	
	mask = probe_irq_mask(val) & 0xffff;

	bridge_ctrl &= ~CB_BRIDGE_INTR;
	config_writew(socket, CB_BRIDGE_CONTROL, bridge_ctrl);

	return mask;
}

/*
 * Set static data that doesn't need re-initializing..
 */
static void yenta_get_socket_capabilities(pci_socket_t *socket, u32 isa_irq_mask)
{
	socket->cap.features |= SS_CAP_PAGE_REGS | SS_CAP_PCCARD | SS_CAP_CARDBUS;
	socket->cap.map_size = 0x1000;
	socket->cap.pci_irq = socket->cb_irq;
	socket->cap.irq_mask = yenta_probe_irq(socket, isa_irq_mask);
	socket->cap.cb_dev = socket->dev;
	socket->cap.bus = NULL;

	printk("Yenta IRQ list %04x, PCI irq%d\n", socket->cap.irq_mask, socket->cb_irq);
}

extern void cardbus_register(pci_socket_t *socket);

/*
 * 'Bottom half' for the yenta_open routine. Allocate the interrupt line
 *  and register the socket with the upper layers.
 */
static void yenta_open_bh(void * data)
{
	pci_socket_t * socket = (pci_socket_t *) data;

	/* It's OK to overwrite this now */
	socket->tq_task.routine = yenta_bh;

	if (!socket->cb_irq || request_irq(socket->cb_irq, yenta_interrupt, SA_SHIRQ, socket->dev->name, socket)) {
		/* No IRQ or request_irq failed. Poll */
		socket->cb_irq = 0; /* But zero is a valid IRQ number. */
		socket->poll_timer.function = yenta_interrupt_wrapper;
		socket->poll_timer.data = (unsigned long)socket;
		socket->poll_timer.expires = jiffies + HZ;
		add_timer(&socket->poll_timer);
	}

	/* Figure out what the dang thing can do for the PCMCIA layer... */
	yenta_get_socket_capabilities(socket, isa_interrupts);
	printk("Socket status: %08x\n", cb_readl(socket, CB_SOCKET_STATE));

	/* Register it with the pcmcia layer.. */
	cardbus_register(socket);

	MOD_DEC_USE_COUNT;
}

static void yenta_clear_maps(pci_socket_t *socket)
{
	int i;
	pccard_io_map io = { 0, 0, 0, 0, 1 };
	pccard_mem_map mem = { 0, 0, 0, 0, 0, 0 };

	mem.sys_stop = 0x0fff;
	yenta_set_socket(socket, &dead_socket);
	for (i = 0; i < 2; i++) {
		io.map = i;
		yenta_set_io_map(socket, &io);
	}
	for (i = 0; i < 5; i++) {
		mem.map = i;
		yenta_set_mem_map(socket, &mem);
	}
}

/*
 * Initialize the standard cardbus registers
 */
static void yenta_config_init(pci_socket_t *socket)
{
	u16 bridge;
	struct pci_dev *dev = socket->dev;

	pci_set_power_state(socket->dev, 0);

	config_writel(socket, CB_LEGACY_MODE_BASE, 0);
	config_writel(socket, PCI_BASE_ADDRESS_0, dev->resource[0].start);
	config_writew(socket, PCI_COMMAND,
			PCI_COMMAND_IO |
			PCI_COMMAND_MEMORY |
			PCI_COMMAND_MASTER |
			PCI_COMMAND_WAIT);

	/* MAGIC NUMBERS! Fixme */
	config_writeb(socket, PCI_CACHE_LINE_SIZE, L1_CACHE_BYTES / 4);
	config_writeb(socket, PCI_LATENCY_TIMER, 168);
	config_writeb(socket, PCI_SEC_LATENCY_TIMER, 176);
	config_writeb(socket, PCI_PRIMARY_BUS, dev->bus->number);
	config_writeb(socket, PCI_SECONDARY_BUS, dev->subordinate->number);
	config_writeb(socket, PCI_SUBORDINATE_BUS, dev->subordinate->number);

	/*
	 * Set up the bridging state:
	 *  - enable write posting.
	 *  - memory window 0 prefetchable, window 1 non-prefetchable
	 *  - PCI interrupts enabled if a PCI interrupt exists..
	 */
	bridge = config_readw(socket, CB_BRIDGE_CONTROL);
	bridge &= ~(CB_BRIDGE_CRST | CB_BRIDGE_PREFETCH1 | CB_BRIDGE_INTR | CB_BRIDGE_ISAEN | CB_BRIDGE_VGAEN);
	bridge |= CB_BRIDGE_PREFETCH0 | CB_BRIDGE_POSTEN;
	if (!socket->cb_irq)
		bridge |= CB_BRIDGE_INTR;
	config_writew(socket, CB_BRIDGE_CONTROL, bridge);

	exca_writeb(socket, I365_GBLCTL, 0x00);
	exca_writeb(socket, I365_GENCTL, 0x00);

	/* Redo card voltage interrogation */
	cb_writel(socket, CB_SOCKET_FORCE, CB_CVSTEST);
}

/* Called at resume and initialization events */
static int yenta_init(pci_socket_t *socket)
{
	yenta_config_init(socket);
	yenta_clear_maps(socket);
	return 0;
}

static int yenta_suspend(pci_socket_t *socket)
{
	yenta_set_socket(socket, &dead_socket);

	/*
	 * This does not work currently. The controller
	 * loses too much informationduring D3 to come up
	 * cleanly. We should probably fix yenta_init()
	 * to update all the critical registers, notably
	 * the IO and MEM bridging region data.. That is
	 * something that pci_set_power_state() should
	 * probably know about bridges anyway.
	 *
	pci_set_power_state(socket->dev, 3);
	 */

	return 0;
}

static void yenta_allocate_res(pci_socket_t *socket, int nr, unsigned type)
{
	struct pci_bus *bus;
	struct resource *root, *res;
	u32 start, end;
	u32 align, size, min, max;
	unsigned offset;

	offset = 0x1c + 8*nr;
	bus = socket->dev->subordinate;
	res = socket->dev->resource + PCI_BRIDGE_RESOURCES + nr;
	res->name = bus->name;
	res->flags = type;
	res->start = 0;
	res->end = 0;
	root = pci_find_parent_resource(socket->dev, res);

	if (!root)
		return;

	start = config_readl(socket, offset);
	end = config_readl(socket, offset+4) | 0xfff;
	if (start && end > start) {
		res->start = start;
		res->end = end;
		request_resource(root, res);
		return;
	}

	align = size = 4*1024*1024;
	min = PCIBIOS_MIN_MEM; max = ~0U;
	if (type & IORESOURCE_IO) {
		align = 1024;
		size = 256;
		min = PCIBIOS_MIN_IO;
		max = 0xffff;
	}
		
	if (allocate_resource(root, res, size, min, max, align, NULL, NULL) < 0)
		return;

	config_writel(socket, offset, res->start);
	config_writel(socket, offset+4, res->end);
}

/*
 * Allocate the bridge mappings for the device..
 */
static void yenta_allocate_resources(pci_socket_t *socket)
{
	yenta_allocate_res(socket, 0, IORESOURCE_MEM|IORESOURCE_PREFETCH);
	yenta_allocate_res(socket, 1, IORESOURCE_MEM);
	yenta_allocate_res(socket, 2, IORESOURCE_IO);
	yenta_allocate_res(socket, 3, IORESOURCE_IO);	/* PCI isn't clever enough to use this one yet */
}

/*
 * Close it down - release our resources and go home..
 */
static void yenta_close(pci_socket_t *sock)
{
	if (sock->cb_irq)
		free_irq(sock->cb_irq, sock);
	else
		del_timer_sync(&sock->poll_timer);

	if (sock->base)
		iounmap(sock->base);
}

#include "ti113x.h"
#include "ricoh.h"

/*
 * Different cardbus controllers have slightly different
 * initialization sequences etc details. List them here..
 */
#define PD(x,y) PCI_VENDOR_ID_##x, PCI_DEVICE_ID_##x##_##y
static struct cardbus_override_struct {
	unsigned short vendor;
	unsigned short device;
	struct pci_socket_ops *op;
} cardbus_override[] = {
	{ PD(TI,1130),	&ti113x_ops },
	{ PD(TI,1031),	&ti_ops },
	{ PD(TI,1131),	&ti113x_ops },
	{ PD(TI,1250),	&ti1250_ops },
	{ PD(TI,1220),	&ti_ops },
	{ PD(TI,1221),	&ti_ops },
	{ PD(TI,1210),	&ti_ops },
	{ PD(TI,1450),	&ti_ops },
	{ PD(TI,1225),	&ti_ops },
	{ PD(TI,1251A),	&ti_ops },
	{ PD(TI,1211),	&ti_ops },
	{ PD(TI,1251B),	&ti_ops },
	{ PD(TI,1420),	&ti_ops },

	{ PD(RICOH,RL5C465), &ricoh_ops },
	{ PD(RICOH,RL5C466), &ricoh_ops },
	{ PD(RICOH,RL5C475), &ricoh_ops },
	{ PD(RICOH,RL5C476), &ricoh_ops },
	{ PD(RICOH,RL5C478), &ricoh_ops }
};

#define NR_OVERRIDES (sizeof(cardbus_override)/sizeof(struct cardbus_override_struct))

/*
 * Initialize a cardbus controller. Make sure we have a usable
 * interrupt, and that we can map the cardbus area. Fill in the
 * socket information structure..
 */
static int yenta_open(pci_socket_t *socket)
{
	int i;
	struct pci_dev *dev = socket->dev;

	/*
	 * Do some basic sanity checking..
	 */
	if (pci_enable_device(dev))
		return -1;
	if (!pci_resource_start(dev, 0)) {
		printk("No cardbus resource!\n");
		return -1;
	}

	/*
	 * Ok, start setup.. Map the cardbus registers,
	 * and request the IRQ.
	 */
	socket->base = ioremap(pci_resource_start(dev, 0), 0x1000);
	if (!socket->base)
		return -1;

	yenta_config_init(socket);

	/* Disable all events */
	cb_writel(socket, CB_SOCKET_MASK, 0x0);

	/* Set up the bridge regions.. */
	yenta_allocate_resources(socket);

	socket->cb_irq = dev->irq;

	/* Do we have special options for the device? */
	for (i = 0; i < NR_OVERRIDES; i++) {
		struct cardbus_override_struct *d = cardbus_override+i;
		if (dev->vendor == d->vendor && dev->device == d->device) {
			socket->op = d->op;
			if (d->op->open) {
				int retval = d->op->open(socket);
				if (retval < 0)
					return retval;
			}
		}
	}

	/* Get the PCMCIA kernel thread to complete the
	   initialisation later. We can't do this here,
	   because, er, because Linus says so :)
	*/
	socket->tq_task.routine = yenta_open_bh;
	socket->tq_task.data = socket;

	MOD_INC_USE_COUNT;
	schedule_task(&socket->tq_task);

	return 0;
}

/*
 * Standard plain cardbus - no frills, no extensions
 */
struct pci_socket_ops yenta_operations = {
	yenta_open,
	yenta_close,
	yenta_init,
	yenta_suspend,
	yenta_get_status,
	yenta_get_socket,
	yenta_set_socket,
	yenta_get_io_map,
	yenta_set_io_map,
	yenta_get_mem_map,
	yenta_set_mem_map,
	yenta_proc_setup
};
EXPORT_SYMBOL(yenta_operations);