switch-coreboot/device/pcix_device.c

/*
 * This file is part of the LinuxBIOS project.
 *
 * Copyright (C) 2005 Linux Networx
 * (Written by Eric Biederman <ebiederman@lnxi.com> for Linux Networx)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 */

#include <console.h>
#include <device/device.h>
#include <device/pci.h>
#include <device/pci_ids.h>
#include <device/pcix.h>

static void pcix_tune_dev(struct device *dev)
{
	unsigned int cap;
	unsigned int status, orig_cmd, cmd;
	unsigned int max_read, max_tran;

	if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL) {
		return;
	}
	cap = pci_find_capability(dev, PCI_CAP_ID_PCIX);
	if (!cap) {
		return;
	}
	printk(BIOS_DEBUG, "%s PCI-X tuning\n", dev_path(dev));
	status = pci_read_config32(dev, cap + PCI_X_STATUS);
	orig_cmd = cmd = pci_read_config16(dev, cap + PCI_X_CMD);

	max_read = (status & PCI_X_STATUS_MAX_READ) >> 21;
	max_tran = (status & PCI_X_STATUS_MAX_SPLIT) >> 23;
	if (max_read != ((cmd & PCI_X_CMD_MAX_READ) >> 2)) {
		cmd &= ~PCI_X_CMD_MAX_READ;
		cmd |= max_read << 2;
	}
	if (max_tran != ((cmd & PCI_X_CMD_MAX_SPLIT) >> 4)) {
		cmd &= ~PCI_X_CMD_MAX_SPLIT;
		cmd |= max_tran << 4;
	}
	/* Don't attempt to handle PCI-X errors. */
	cmd &= ~PCI_X_CMD_DPERR_E;
	/* Enable Relaxed Ordering. */
	cmd |= PCI_X_CMD_ERO;
	if (orig_cmd != cmd) {
		pci_write_config16(dev, cap + PCI_X_CMD, cmd);
	}
}

unsigned int pcix_scan_bus(struct bus *bus, unsigned int min_devfn,
			   unsigned int max_devfn, unsigned int max)
{
	struct device *child;
	max = pci_scan_bus(bus, min_devfn, max_devfn, max);
	for (child = bus->children; child; child = child->sibling) {
		if ((child->path.u.pci.devfn < min_devfn) ||
		    (child->path.u.pci.devfn > max_devfn)) {
			continue;
		}
		pcix_tune_dev(child);
	}
	return max;
}

const char *pcix_speed(unsigned int sstatus)
{
	static const char conventional[] = "Conventional PCI";
	static const char pcix_66mhz[] = "66MHz PCI-X";
	static const char pcix_100mhz[] = "100MHz PCI-X";
	static const char pcix_133mhz[] = "133MHz PCI-X";
	static const char pcix_266mhz[] = "266MHz PCI-X";
	static const char pcix_533mhz[] = "533MHZ PCI-X";
	static const char unknown[] = "Unknown";
	const char *result;

	result = unknown;
	switch (PCI_X_SSTATUS_MFREQ(sstatus)) {
	case PCI_X_SSTATUS_CONVENTIONAL_PCI:
		result = conventional;
		break;
	case PCI_X_SSTATUS_MODE1_66MHZ:
		result = pcix_66mhz;
		break;
	case PCI_X_SSTATUS_MODE1_100MHZ:
		result = pcix_100mhz;
		break;
	case PCI_X_SSTATUS_MODE1_133MHZ:
		result = pcix_133mhz;
		break;
	case PCI_X_SSTATUS_MODE2_266MHZ_REF_66MHZ:
	case PCI_X_SSTATUS_MODE2_266MHZ_REF_100MHZ:
	case PCI_X_SSTATUS_MODE2_266MHZ_REF_133MHZ:
		result = pcix_266mhz;
		break;
	case PCI_X_SSTATUS_MODE2_533MHZ_REF_66MHZ:
	case PCI_X_SSTATUS_MODE2_533MHZ_REF_100MHZ:
	case PCI_X_SSTATUS_MODE2_533MHZ_REF_133MHZ:
		result = pcix_533mhz;
		break;
	}
	return result;
}

unsigned int pcix_scan_bridge(struct device *dev, unsigned int max)
{
	unsigned int pos, status;

	/* Find the PCI-X capability. */
	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
	sstatus = pci_read_config16(dev, pos + PCI_X_SEC_STATUS);

	if (PCI_X_SSTATUS_MFREQ(sstatus) == PCI_X_SSTATUS_CONVENTIONAL_PCI) {
		max = do_pci_scan_bridge(dev, max, pci_scan_bus);
	} else {
		max = do_pci_scan_bridge(dev, max, pcix_scan_bus);
	}

	/* Print the PCI-X bus speed. */
	printk(BIOS_DEBUG, "PCI-X: %02x: %s\n", dev->link[0].secondary,
		     pcix_speed(sstatus));

	return max;
}

/** Default device operations for PCI-X bridges. */
static const struct pci_operations pcix_bus_ops_pci = {
	.set_subsystem = 0,
};

const struct device_operations default_pcix_ops_bus = {
	.read_resources   = pci_bus_read_resources,
	.set_resources    = pci_dev_set_resources,
	.enable_resources = pci_bus_enable_resources,
	.init             = 0,
	.scan_bus         = pcix_scan_bridge,
	.enable           = 0,
	.reset_bus        = pci_bus_reset,
	.ops_pci          = &pcix_bus_ops_pci,
};