xref: /src/sys/arch/atari/pci/pci_machdep.c

/*	$NetBSD: pci_machdep.c,v 1.65 2024/09/07 06:17:38 andvar Exp $	*/

/*
 * Copyright (c) 1996 Leo Weppelman.  All rights reserved.
 * Copyright (c) 1996, 1997 Christopher G. Demetriou.  All rights reserved.
 * Copyright (c) 1994 Charles M. Hannum.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Charles M. Hannum.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: pci_machdep.c,v 1.65 2024/09/07 06:17:38 andvar Exp $");

#include "opt_mbtype.h"

#include <sys/types.h>
#include <sys/param.h>
#include <sys/time.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/device.h>
#include <sys/kmem.h>

#define _ATARI_BUS_DMA_PRIVATE
#include <sys/bus.h>

#include <dev/pci/pcivar.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcidevs.h>

#include <uvm/uvm_extern.h>

#include <machine/cpu.h>
#include <machine/iomap.h>
#include <machine/mfp.h>

#include <atari/atari/device.h>
#include <atari/pci/pci_vga.h>

/*
 * Sizes of pci memory and I/O area.
 */
#define PCI_MEM_END     0x10000000      /* 256 MByte */
#define PCI_IO_END      0x10000000      /* 256 MByte */

/*
 * We preserve some space at the begin of the pci area for 32BIT_1M
 * devices and standard vga.
 */
#define PCI_MEM_START   0x00100000      /*   1 MByte */
#define PCI_IO_START    0x00004000      /*  16 kByte (some PCI cards allow only
					    I/O addresses up to 0xffff) */

/*
 * PCI memory and IO should be aligned according to these masks
 */
#define PCI_MACHDEP_IO_ALIGN_MASK	0xffffff00
#define PCI_MACHDEP_MEM_ALIGN_MASK	0xfffff000

/*
 * Convert a PCI 'device' number to a slot number.
 */
#define	DEV2SLOT(dev)	(3 - dev)

/*
 * Struct to hold the memory and I/O datas of the pci devices
 */
struct pci_memreg {
	LIST_ENTRY(pci_memreg) link;
	int dev;
	pcitag_t tag;
	pcireg_t reg, address, mask;
	uint32_t size;
	uint32_t csr;
};

typedef LIST_HEAD(pci_memreg_head, pci_memreg) PCI_MEMREG;

/*
 * Entry points for PCI DMA.  Use only the 'standard' functions.
 */
int	_bus_dmamap_create(bus_dma_tag_t, bus_size_t, int, bus_size_t,
	    bus_size_t, int, bus_dmamap_t *);
struct atari_bus_dma_tag pci_bus_dma_tag = {
	0,
#if defined(_ATARIHW_)
	0x80000000, /* On the Hades, CPU memory starts here PCI-wise */
#else
	0,
#endif
	_bus_dmamap_create,
	_bus_dmamap_destroy,
	_bus_dmamap_load,
	_bus_dmamap_load_mbuf,
	_bus_dmamap_load_uio,
	_bus_dmamap_load_raw,
	_bus_dmamap_unload,
	_bus_dmamap_sync,
};

int	ataripcibusprint(void *, const char *);
int	pcibusmatch(device_t, cfdata_t, void *);
void	pcibusattach(device_t, device_t, void *);

static void enable_pci_devices(void);
static void insert_into_list(PCI_MEMREG *head, struct pci_memreg *elem);
static int overlap_pci_areas(struct pci_memreg *p,
    struct pci_memreg *self, u_int addr, u_int size, u_int what);

CFATTACH_DECL_NEW(pcib, 0,
    pcibusmatch, pcibusattach, NULL, NULL);

/*
 * We need some static storage to probe pci-busses for VGA cards during
 * early console init.
 */
static struct atari_bus_space	bs_storage[2];	/* 1 iot, 1 memt */

int
pcibusmatch(device_t parent, cfdata_t cf, void *aux)
{
	static int nmatched = 0;

	if (strcmp((char *)aux, "pcib"))
		return 0;	/* Wrong number... */

	if (atari_realconfig == 0)
		return 1;

	if ((machineid & (ATARI_HADES|ATARI_MILAN)) != 0) {
		/*
		 * Both Hades and Milan have only one pci bus
		 */
		if (nmatched)
			return 0;
		nmatched++;
		return 1;
	}
	return 0;
}

void
pcibusattach(device_t parent, device_t self, void *aux)
{
	struct pcibus_attach_args pba;

	pba.pba_pc      = NULL;
	pba.pba_bus     = 0;
	pba.pba_bridgetag = NULL;
	pba.pba_flags	= PCI_FLAGS_IO_OKAY | PCI_FLAGS_MEM_OKAY;
	pba.pba_dmat	= &pci_bus_dma_tag;
	pba.pba_iot     = leb_alloc_bus_space_tag(&bs_storage[0]);
	pba.pba_memt    = leb_alloc_bus_space_tag(&bs_storage[1]);
	if ((pba.pba_iot == NULL) || (pba.pba_memt == NULL)) {
		printf("leb_alloc_bus_space_tag failed!\n");
		return;
	}
	pba.pba_iot->base  = PCI_IO_PHYS;
	pba.pba_memt->base = PCI_MEM_PHYS;

	if (self == NULL) {
		/*
		 * Scan the bus for a VGA-card that we support. If we
		 * find one, try to initialize it to a 'standard' text
		 * mode (80x25).
		 */
		check_for_vga(pba.pba_iot, pba.pba_memt);
		return;
	}

	enable_pci_devices();

#if defined(_ATARIHW_)
	MFP2->mf_aer &= ~(0x27); /* PCI interrupts: HIGH -> LOW */
#endif

	printf("\n");

	config_found(self, &pba, ataripcibusprint, CFARGS_NONE);
}

int
ataripcibusprint(void *aux, const char *name)
{

	if (name == NULL)
		return UNCONF;
	return QUIET;
}

void
pci_attach_hook(device_t parent, device_t self, struct pcibus_attach_args *pba)
{
}

/*
 * Initialize the PCI-bus. The Atari-BIOS does not do this, so....
 * We only disable all devices here. Memory and I/O enabling is done
 * later at pcibusattach.
 */
void
init_pci_bus(void)
{
	pci_chipset_tag_t	pc = NULL; /* XXX */
	pcitag_t		tag;
	pcireg_t		csr;
	int			device, maxndevs;
	uint32_t		id;

	tag   = 0;
	id    = 0;

	maxndevs = pci_bus_maxdevs(pc, 0);

	for (device = 0; device < maxndevs; device++) {

		tag = pci_make_tag(pc, 0, device, 0);
		id  = pci_conf_read(pc, tag, PCI_ID_REG);
		if (id == 0 || id == 0xffffffff)
			continue;

		csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
		csr &= ~(PCI_COMMAND_MEM_ENABLE|PCI_COMMAND_IO_ENABLE);
		csr &= ~PCI_COMMAND_MASTER_ENABLE;
		pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr);
	}
}

/*
 * insert a new element in an existing list that the ID's (size in struct
 * pci_memreg) are sorted.
 */
static void
insert_into_list(PCI_MEMREG *head, struct pci_memreg *elem)
{
	struct pci_memreg *p, *q;

	p = LIST_FIRST(head);
	q = NULL;

	for (; p != NULL && p->size < elem->size;
	    q = p, p = LIST_NEXT(p, link))
		;

	if (q == NULL) {
		LIST_INSERT_HEAD(head, elem, link);
	} else {
		LIST_INSERT_AFTER(q, elem, link);
	}
}

/*
 * Test if a new selected area overlaps with an already (probably preselected)
 * pci area.
 */
static int
overlap_pci_areas(struct pci_memreg *p, struct pci_memreg *self, u_int addr,
    u_int size, u_int what)
{
	struct pci_memreg *q;

	if (p == NULL)
		return 0;

	q = p;
	while (q != NULL) {
		if ((q != self) && (q->csr & what)) {
			if ((addr >= q->address) &&
			    (addr < (q->address + q->size))) {
#ifdef DEBUG_PCI_MACHDEP
				printf("\noverlap area dev %d reg 0x%02x "
				    "with dev %d reg 0x%02x",
				    self->dev, self->reg, q->dev, q->reg);
#endif
				return 1;
			}
			if ((q->address >= addr) &&
			    (q->address < (addr + size))) {
#ifdef DEBUG_PCI_MACHDEP
				printf("\noverlap area dev %d reg 0x%02x "
				    "with dev %d reg 0x%02x",
				    self->dev, self->reg, q->dev, q->reg);
#endif
				return 1;
			}
		}
		q = LIST_NEXT(q, link);
	}
	return 0;
}

/*
 * Enable memory and I/O on pci devices. Care about already enabled devices
 * (probably by the console driver).
 *
 * The idea behind the following code is:
 * We build a by sizes sorted list of the requirements of the different
 * pci devices. After that we choose the start addresses of that areas
 * in such a way that they are placed as closed as possible together.
 */
static void
enable_pci_devices(void)
{
	PCI_MEMREG memlist;
	PCI_MEMREG iolist;
	struct pci_memreg *p, *q;
	int dev, reg;
	uint32_t id, class;
	pcitag_t tag;
	pcireg_t csr, address, mask;
	pci_chipset_tag_t pc;
	int sizecnt, membase_1m;

	pc = 0;
	csr = 0;
	tag = 0;

	LIST_INIT(&memlist);
	LIST_INIT(&iolist);

	/*
	 * first step: go through all devices and gather memory and I/O
	 * sizes
	 */
	for (dev = 0; dev < pci_bus_maxdevs(pc,0); dev++) {

		tag = pci_make_tag(pc, 0, dev, 0);
		id  = pci_conf_read(pc, tag, PCI_ID_REG);
		if (id == 0 || id == 0xffffffff)
			continue;

		csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);

		/*
		 * special case: if a display card is found and memory is
		 * enabled preserve 128k at 0xa0000 as vga memory.
		 * XXX: if a display card is found without being enabled,
		 * leave it alone! You will usually only create conflicts
		 * by enabling it.
		 */
		class = pci_conf_read(pc, tag, PCI_CLASS_REG);
		switch (PCI_CLASS(class)) {
		case PCI_CLASS_PREHISTORIC:
		case PCI_CLASS_DISPLAY:
			if (csr & (PCI_COMMAND_MEM_ENABLE |
			    PCI_COMMAND_MASTER_ENABLE)) {
				p = kmem_zalloc(sizeof(struct pci_memreg),
				    KM_SLEEP);
				p->dev = dev;
				p->csr = csr;
				p->tag = tag;
				p->reg = 0;	/* there is no register
						   about this */
				p->size = 0x20000; /* 128kByte */
				p->mask = 0xfffe0000;
				p->address = 0xa0000;

				insert_into_list(&memlist, p);
			} else
				continue;
		}

		for (reg = PCI_MAPREG_START; reg < PCI_MAPREG_END; reg += 4) {
			address = pci_conf_read(pc, tag, reg);
			pci_conf_write(pc, tag, reg, 0xffffffff);
			mask    = pci_conf_read(pc, tag, reg);
			pci_conf_write(pc, tag, reg, address);
			if (mask == 0)
				continue; /* Register unused */

			p = kmem_zalloc(sizeof(struct pci_memreg),
			    KM_SLEEP);
			p->dev = dev;
			p->csr = csr;
			p->tag = tag;
			p->reg = reg;
			p->mask = mask;
			p->address = 0;

			if ((mask & PCI_MAPREG_TYPE_IO) != 0) {
				p->size = PCI_MAPREG_IO_SIZE(mask);

				/*
				 * Align IO if necessary
				 */
				if (p->size < PCI_MAPREG_IO_SIZE(
				    PCI_MACHDEP_IO_ALIGN_MASK)) {
					p->mask = PCI_MACHDEP_IO_ALIGN_MASK;
					p->size = PCI_MAPREG_IO_SIZE(p->mask);
				}

				/*
				 * if I/O is already enabled
				 * (probably by the console driver)
				 * save the address in order to take care
				 * about it later.
				 */
				if ((csr & PCI_COMMAND_IO_ENABLE) != 0)
					p->address = address;

				insert_into_list(&iolist, p);
			} else {
				p->size = PCI_MAPREG_MEM_SIZE(mask);

				/*
				 * Align memory if necessary
				 */
				if (p->size < PCI_MAPREG_IO_SIZE(
				    PCI_MACHDEP_MEM_ALIGN_MASK)) {
					p->mask = PCI_MACHDEP_MEM_ALIGN_MASK;
					p->size = PCI_MAPREG_MEM_SIZE(p->mask);
				}

				/*
				 * if memory is already enabled
				 * (probably by the console driver)
				 * save the address in order to take care
				 * about it later.
				 */
				if ((csr & PCI_COMMAND_MEM_ENABLE) != 0)
					p->address = address;

				insert_into_list(&memlist, p);

				if (PCI_MAPREG_MEM_TYPE(mask) ==
				    PCI_MAPREG_MEM_TYPE_64BIT)
					reg++;
			}
		}

#if defined(_ATARIHW_)
		/*
		 * Both interrupt pin & line are set to the device (== slot)
		 * number. This makes sense on the atari Hades because the
		 * individual slots are hard-wired to a specific MFP-pin.
		 */
		csr  = (DEV2SLOT(dev) << PCI_INTERRUPT_PIN_SHIFT);
		csr |= (DEV2SLOT(dev) << PCI_INTERRUPT_LINE_SHIFT);
		pci_conf_write(pc, tag, PCI_INTERRUPT_REG, csr);
#else
		/*
		 * On the Milan, we accept the BIOS's choice.
		 */
		/*
		 * ..except the secondary IDE interrupt that
		 * the BIOS doesn't setup.
		 */
#define PIIX_PCIB_MBIRQ0	0x70
		if ((PCI_VENDOR(id) == PCI_VENDOR_INTEL) &&
		    (PCI_PRODUCT(id) == PCI_PRODUCT_INTEL_82371FB_ISA)) {
			/*
			 * Set Interrupt Routing for MBIRQ0 to IRQ15.
			 * Note Milan's ROM bootloader v1.2 and v1.4
			 * incorrectly set MBIRQ0 to IRQ14 (not 15)
			 * and unused MBIRQ1 to IRQ 15,
			 * so explicitly disable MBIRQ1.
			 */
			csr = pci_conf_read(pc, tag, PIIX_PCIB_MBIRQ0);
			csr &= ~0x0000ffff;
			/* MBIRQ1: disable, MBIRQ0: IRQ15 */
			csr |=  0x0000800f;
			pci_conf_write(pc, tag, PIIX_PCIB_MBIRQ0, csr);
#ifdef DEBUG_PCI_MACHDEP
			printf("\npcib0: enable and route MBIRQ0 to irq 15\n");
#endif
		}
#endif
	}

	/*
	 * second step: calculate the memory and I/O addresses beginning from
	 * PCI_MEM_START and PCI_IO_START. Care about already mapped areas.
	 *
	 * begin with memory list
	 */

	address = PCI_MEM_START;
	sizecnt = 0;
	membase_1m = 0;
	p = LIST_FIRST(&memlist);
	while (p != NULL) {
		if ((p->csr & PCI_COMMAND_MEM_ENABLE) == 0) {
			if (PCI_MAPREG_MEM_TYPE(p->mask) ==
			    PCI_MAPREG_MEM_TYPE_32BIT_1M) {
				if (p->size > membase_1m)
					membase_1m = p->size;
				do {
					p->address = membase_1m;
					membase_1m += p->size;
				} while (overlap_pci_areas(LIST_FIRST(&memlist),
				    p, p->address, p->size,
				    PCI_COMMAND_MEM_ENABLE));
				if (membase_1m > 0x00100000) {
					/*
					 * Should we panic here?
					 */
					printf("\npcibus0: dev %d reg %d:"
					    " memory not configured",
					    p->dev, p->reg);
					p->reg = 0;
				}
			} else {
				if (sizecnt && (p->size > sizecnt))
					sizecnt =
					    ((p->size + sizecnt) & p->mask) &
					    PCI_MAPREG_MEM_ADDR_MASK;
				if (sizecnt > address) {
					address = sizecnt;
					sizecnt = 0;
				}

				do {
					p->address = address + sizecnt;
					sizecnt += p->size;
				} while (overlap_pci_areas(LIST_FIRST(&memlist),
				    p, p->address, p->size,
				    PCI_COMMAND_MEM_ENABLE));

				if ((address + sizecnt) > PCI_MEM_END) {
					/*
					 * Should we panic here?
					 */
					printf("\npcibus0: dev %d reg %d:"
					    " memory not configured",
					    p->dev, p->reg);
					p->reg = 0;
				}
			}
			if (p->reg > 0) {
				pci_conf_write(pc, p->tag, p->reg, p->address);
				csr = pci_conf_read(pc, p->tag,
				    PCI_COMMAND_STATUS_REG);
				csr |= PCI_COMMAND_MEM_ENABLE |
				    PCI_COMMAND_MASTER_ENABLE;
				pci_conf_write(pc, p->tag,
				    PCI_COMMAND_STATUS_REG, csr);
				p->csr = csr;
			}
		}
		p = LIST_NEXT(p, link);
	}

	/*
	 * now the I/O list
	 */

	address = PCI_IO_START;
	sizecnt = 0;
	p = LIST_FIRST(&iolist);
	while (p != NULL) {
		if (!(p->csr & PCI_COMMAND_IO_ENABLE)) {

			if (sizecnt && (p->size > sizecnt))
				sizecnt = ((p->size + sizecnt) & p->mask) &
				    PCI_MAPREG_IO_ADDR_MASK;
			if (sizecnt > address) {
				address = sizecnt;
				sizecnt = 0;
			}

			do {
				p->address = address + sizecnt;
				sizecnt += p->size;
			} while (overlap_pci_areas(LIST_FIRST(&iolist), p,
			    p->address, p->size, PCI_COMMAND_IO_ENABLE));

			if ((address + sizecnt) > PCI_IO_END) {
				/*
				 * Should we panic here?
				 */
				printf("\npcibus0: dev %d reg %d:"
				    " io not configured",
				    p->dev, p->reg);
			} else {
				pci_conf_write(pc, p->tag, p->reg, p->address);
				csr = pci_conf_read(pc, p->tag,
				    PCI_COMMAND_STATUS_REG);
				csr |= PCI_COMMAND_IO_ENABLE |
				    PCI_COMMAND_MASTER_ENABLE;
				pci_conf_write(pc, p->tag,
				    PCI_COMMAND_STATUS_REG, csr);
				p->csr = csr;
			}
		}
		p = LIST_NEXT(p, link);
	}

#ifdef DEBUG_PCI_MACHDEP
	printf("\nI/O List:\n");
	p = LIST_FIRST(&iolist);

	while (p != NULL) {
		printf("\ndev: %d, reg: 0x%02x, size: 0x%08x, addr: 0x%08x",
		    p->dev, p->reg, p->size, p->address);
		p = LIST_NEXT(p, link);
	}
	printf("\nMemlist:");
	p = LIST_FIRST(&memlist);

	while (p != NULL) {
		printf("\ndev: %d, reg: 0x%02x, size: 0x%08x, addr: 0x%08x",
		    p->dev, p->reg, p->size, p->address);
		p = LIST_NEXT(p, link);
	}
#endif

	/*
	 * Free the lists
	 */
	p = LIST_FIRST(&iolist);
	while (p != NULL) {
		q = p;
		LIST_REMOVE(q, link);
		kmem_free(p, sizeof(*p));
		p = LIST_FIRST(&iolist);
	}
	p = LIST_FIRST(&memlist);
	while (p != NULL) {
		q = p;
		LIST_REMOVE(q, link);
		kmem_free(p, sizeof(*p));
		p = LIST_FIRST(&memlist);
	}
}

pcitag_t
pci_make_tag(pci_chipset_tag_t pc, int bus, int device, int function)
{

	return (bus << 16) | (device << 11) | (function << 8);
}

void
pci_decompose_tag(pci_chipset_tag_t pc, pcitag_t tag, int *bp, int *dp, int *fp)
{

	if (bp != NULL)
		*bp = (tag >> 16) & 0xff;
	if (dp != NULL)
		*dp = (tag >> 11) & 0x1f;
	if (fp != NULL)
		*fp = (tag >> 8) & 0x7;
}

int
pci_intr_map(const struct pci_attach_args *pa, pci_intr_handle_t *ihp)
{
	int line = pa->pa_intrline;

#if defined(_MILANHW_)
	/*
	 * On the Hades, the 'pin' info is useless.
	 */
	{
		int pin = pa->pa_intrpin;

		if (pin == 0) {
			/* No IRQ used. */
			goto bad;
		}
		if (pin > PCI_INTERRUPT_PIN_MAX) {
			printf("pci_intr_map: bad interrupt pin %d\n", pin);
			goto bad;
		}
	}
#endif /* _MILANHW_ */

	/*
	 * According to the PCI-spec, 255 means `unknown' or `no connection'.
	 * Interpret this as 'no interrupt assigned'.
	 */
	if (line == 255)
		goto bad;

	/*
	 * Values are pretty useless on the Hades since all interrupt
	 * lines for a card are tied together and hardwired to a
	 * specific TT-MFP I/O port.
	 * On the Milan, they are tied to the ICU.
	 */
#if defined(_MILANHW_)
	if (line >= 16) {
		printf("pci_intr_map: bad interrupt line %d\n", line);
		goto bad;
	}
	if (line == 2) {
		printf("pci_intr_map: changed line 2 to line 9\n");
		line = 9;
	}
	/* Assume line == 0 means unassigned */
	if (line == 0)
		goto bad;
#endif
	*ihp = line;
	return 0;

bad:
	*ihp = -1;
	return 1;
}

const char *
pci_intr_string(pci_chipset_tag_t pc, pci_intr_handle_t ih, char *buf,
    size_t len)
{

	if (ih == -1)
		panic("pci_intr_string: bogus handle 0x%x", ih);

	snprintf(buf, len, "irq %d", ih);
	return buf;
}

const struct evcnt *
pci_intr_evcnt(pci_chipset_tag_t pc, pci_intr_handle_t ih)
{

	/* XXX for now, no evcnt parent reported */
	return NULL;
}