[PATCH] ioc4: Enable build on non-SN2

The SGI PCI-RT card, based on the SGI IOC4 chip, will be made available on
Altix XE (x86_64) platforms in the near future.  As such it is now a
misnomer for the IOC4 base device driver to live under drivers/sn, and
would complicate builds for non-SN2.

This patch moves the IOC4 base driver code from drivers/sn to drivers/misc,
and updates the associated Makefiles and Kconfig files to allow building on
non-SN2 configs.  Due to the resulting change in link order, it is now
necessary to use late_initcall() for IOC4 subdriver initialization.

[akpm@osdl.org: __udivdi3 fix]
[akpm@osdl.org: fix default in Kconfig]
Acked-by: Pat Gefre <pfg@sgi.com>
Acked-by: Jeremy Higdon <jeremy@sgi.com>
Signed-off-by: Brent Casavant <bcasavan@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 0 insertions, 487 deletions

diff --git a/drivers/sn/Kconfig b/drivers/sn/Kconfig
index 34d4fde..c66ba9a 100644
--- a/drivers/sn/Kconfig
+++ b/drivers/sn/Kconfig
@@ -5,18 +5,6 @@
 menu "SN Devices"
 	depends on SGI_SN
 
-config SGI_IOC4
-	tristate "SGI IOC4 Base IO support"
-	default m
-	---help---
-	This option enables basic support for the IOC4 chip on certain
-	SGI IO controller cards (IO9, IO10, and PCI-RT).  This option
-	does not enable any specific functions on such a card, but provides
-	necessary infrastructure for other drivers to utilize.
-
-	If you have an SGI Altix with an IOC4-based card say Y.
-	Otherwise say N.
-
 config SGI_IOC3
 	tristate "SGI IOC3 Base IO support"
 	default m
diff --git a/drivers/sn/Makefile b/drivers/sn/Makefile
index 2cda011..693db8b 100644
--- a/drivers/sn/Makefile
+++ b/drivers/sn/Makefile
@@ -3,5 +3,4 @@
 #
 #
 
-obj-$(CONFIG_SGI_IOC4) += ioc4.o
 obj-$(CONFIG_SGI_IOC3) += ioc3.o
diff --git a/drivers/sn/ioc4.c b/drivers/sn/ioc4.c
deleted file mode 100644
index 83d2e90..0000000
--- a/drivers/sn/ioc4.c
+++ /dev/null
@@ -1,474 +0,0 @@
-/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License.  See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (C) 2005-2006 Silicon Graphics, Inc.  All Rights Reserved.
- */
-
-/* This file contains the master driver module for use by SGI IOC4 subdrivers.
- *
- * It allocates any resources shared between multiple subdevices, and
- * provides accessor functions (where needed) and the like for those
- * resources.  It also provides a mechanism for the subdevice modules
- * to support loading and unloading.
- *
- * Non-shared resources (e.g. external interrupt A_INT_OUT register page
- * alias, serial port and UART registers) are handled by the subdevice
- * modules themselves.
- *
- * This is all necessary because IOC4 is not implemented as a multi-function
- * PCI device, but an amalgamation of disparate registers for several
- * types of device (ATA, serial, external interrupts).  The normal
- * resource management in the kernel doesn't have quite the right interfaces
- * to handle this situation (e.g. multiple modules can't claim the same
- * PCI ID), thus this IOC4 master module.
- */
-
-#include <linux/errno.h>
-#include <linux/module.h>
-#include <linux/pci.h>
-#include <linux/ioc4.h>
-#include <linux/ktime.h>
-#include <linux/mutex.h>
-#include <linux/time.h>
-#include <asm/sn/addrs.h>
-#include <asm/sn/clksupport.h>
-#include <asm/sn/shub_mmr.h>
-
-/***************
- * Definitions *
- ***************/
-
-/* Tweakable values */
-
-/* PCI bus speed detection/calibration */
-#define IOC4_CALIBRATE_COUNT 63		/* Calibration cycle period */
-#define IOC4_CALIBRATE_CYCLES 256	/* Average over this many cycles */
-#define IOC4_CALIBRATE_DISCARD 2	/* Discard first few cycles */
-#define IOC4_CALIBRATE_LOW_MHZ 25	/* Lower bound on bus speed sanity */
-#define IOC4_CALIBRATE_HIGH_MHZ 75	/* Upper bound on bus speed sanity */
-#define IOC4_CALIBRATE_DEFAULT_MHZ 66	/* Assumed if sanity check fails */
-
-/************************
- * Submodule management *
- ************************/
-
-static DEFINE_MUTEX(ioc4_mutex);
-
-static LIST_HEAD(ioc4_devices);
-static LIST_HEAD(ioc4_submodules);
-
-/* Register an IOC4 submodule */
-int
-ioc4_register_submodule(struct ioc4_submodule *is)
-{
-	struct ioc4_driver_data *idd;
-
-	mutex_lock(&ioc4_mutex);
-	list_add(&is->is_list, &ioc4_submodules);
-
-	/* Initialize submodule for each IOC4 */
-	if (!is->is_probe)
-		goto out;
-
-	list_for_each_entry(idd, &ioc4_devices, idd_list) {
-		if (is->is_probe(idd)) {
-			printk(KERN_WARNING
-			       "%s: IOC4 submodule %s probe failed "
-			       "for pci_dev %s",
-			       __FUNCTION__, module_name(is->is_owner),
-			       pci_name(idd->idd_pdev));
-		}
-	}
- out:
-	mutex_unlock(&ioc4_mutex);
-	return 0;
-}
-
-/* Unregister an IOC4 submodule */
-void
-ioc4_unregister_submodule(struct ioc4_submodule *is)
-{
-	struct ioc4_driver_data *idd;
-
-	mutex_lock(&ioc4_mutex);
-	list_del(&is->is_list);
-
-	/* Remove submodule for each IOC4 */
-	if (!is->is_remove)
-		goto out;
-
-	list_for_each_entry(idd, &ioc4_devices, idd_list) {
-		if (is->is_remove(idd)) {
-			printk(KERN_WARNING
-			       "%s: IOC4 submodule %s remove failed "
-			       "for pci_dev %s.\n",
-			       __FUNCTION__, module_name(is->is_owner),
-			       pci_name(idd->idd_pdev));
-		}
-	}
- out:
-	mutex_unlock(&ioc4_mutex);
-}
-
-/*********************
- * Device management *
- *********************/
-
-#define IOC4_CALIBRATE_LOW_LIMIT \
-	(1000*IOC4_EXTINT_COUNT_DIVISOR/IOC4_CALIBRATE_LOW_MHZ)
-#define IOC4_CALIBRATE_HIGH_LIMIT \
-	(1000*IOC4_EXTINT_COUNT_DIVISOR/IOC4_CALIBRATE_HIGH_MHZ)
-#define IOC4_CALIBRATE_DEFAULT \
-	(1000*IOC4_EXTINT_COUNT_DIVISOR/IOC4_CALIBRATE_DEFAULT_MHZ)
-
-#define IOC4_CALIBRATE_END \
-	(IOC4_CALIBRATE_CYCLES + IOC4_CALIBRATE_DISCARD)
-
-#define IOC4_INT_OUT_MODE_TOGGLE 0x7	/* Toggle INT_OUT every COUNT+1 ticks */
-
-/* Determines external interrupt output clock period of the PCI bus an
- * IOC4 is attached to.  This value can be used to determine the PCI
- * bus speed.
- *
- * IOC4 has a design feature that various internal timers are derived from
- * the PCI bus clock.  This causes IOC4 device drivers to need to take the
- * bus speed into account when setting various register values (e.g. INT_OUT
- * register COUNT field, UART divisors, etc).  Since this information is
- * needed by several subdrivers, it is determined by the main IOC4 driver,
- * even though the following code utilizes external interrupt registers
- * to perform the speed calculation.
- */
-static void
-ioc4_clock_calibrate(struct ioc4_driver_data *idd)
-{
-	union ioc4_int_out int_out;
-	union ioc4_gpcr gpcr;
-	unsigned int state, last_state = 1;
-	struct timespec start_ts, end_ts;
-	uint64_t start, end, period;
-	unsigned int count = 0;
-
-	/* Enable output */
-	gpcr.raw = 0;
-	gpcr.fields.dir = IOC4_GPCR_DIR_0;
-	gpcr.fields.int_out_en = 1;
-	writel(gpcr.raw, &idd->idd_misc_regs->gpcr_s.raw);
-
-	/* Reset to power-on state */
-	writel(0, &idd->idd_misc_regs->int_out.raw);
-	mmiowb();
-
-	/* Set up square wave */
-	int_out.raw = 0;
-	int_out.fields.count = IOC4_CALIBRATE_COUNT;
-	int_out.fields.mode = IOC4_INT_OUT_MODE_TOGGLE;
-	int_out.fields.diag = 0;
-	writel(int_out.raw, &idd->idd_misc_regs->int_out.raw);
-	mmiowb();
-
-	/* Check square wave period averaged over some number of cycles */
-	do {
-		int_out.raw = readl(&idd->idd_misc_regs->int_out.raw);
-		state = int_out.fields.int_out;
-		if (!last_state && state) {
-			count++;
-			if (count == IOC4_CALIBRATE_END) {
-				ktime_get_ts(&end_ts);
-				break;
-			} else if (count == IOC4_CALIBRATE_DISCARD)
-				ktime_get_ts(&start_ts);
-		}
-		last_state = state;
-	} while (1);
-
-	/* Calculation rearranged to preserve intermediate precision.
-	 * Logically:
-	 * 1. "end - start" gives us the measurement period over all
-	 *    the square wave cycles.
-	 * 2. Divide by number of square wave cycles to get the period
-	 *    of a square wave cycle.
-	 * 3. Divide by 2*(int_out.fields.count+1), which is the formula
-	 *    by which the IOC4 generates the square wave, to get the
-	 *    period of an IOC4 INT_OUT count.
-	 */
-	end = end_ts.tv_sec * NSEC_PER_SEC + end_ts.tv_nsec;
-	start = start_ts.tv_sec * NSEC_PER_SEC + start_ts.tv_nsec;
-	period = (end - start) /
-		(IOC4_CALIBRATE_CYCLES * 2 * (IOC4_CALIBRATE_COUNT + 1));
-
-	/* Bounds check the result. */
-	if (period > IOC4_CALIBRATE_LOW_LIMIT ||
-	    period < IOC4_CALIBRATE_HIGH_LIMIT) {
-		printk(KERN_INFO
-		       "IOC4 %s: Clock calibration failed.  Assuming"
-		       "PCI clock is %d ns.\n",
-		       pci_name(idd->idd_pdev),
-		       IOC4_CALIBRATE_DEFAULT / IOC4_EXTINT_COUNT_DIVISOR);
-		period = IOC4_CALIBRATE_DEFAULT;
-	} else {
-		printk(KERN_DEBUG
-		       "IOC4 %s: PCI clock is %ld ns.\n",
-		       pci_name(idd->idd_pdev),
-		       period / IOC4_EXTINT_COUNT_DIVISOR);
-	}
-
-	/* Remember results.  We store the extint clock period rather
-	 * than the PCI clock period so that greater precision is
-	 * retained.  Divide by IOC4_EXTINT_COUNT_DIVISOR to get
-	 * PCI clock period.
-	 */
-	idd->count_period = period;
-}
-
-/* There are three variants of IOC4 cards: IO9, IO10, and PCI-RT.
- * Each brings out different combinations of IOC4 signals, thus.
- * the IOC4 subdrivers need to know to which we're attached.
- *
- * We look for the presence of a SCSI (IO9) or SATA (IO10) controller
- * on the same PCI bus at slot number 3 to differentiate IO9 from IO10.
- * If neither is present, it's a PCI-RT.
- */
-static unsigned int
-ioc4_variant(struct ioc4_driver_data *idd)
-{
-	struct pci_dev *pdev = NULL;
-	int found = 0;
-
-	/* IO9: Look for a QLogic ISP 12160 at the same bus and slot 3. */
-	do {
-		pdev = pci_get_device(PCI_VENDOR_ID_QLOGIC,
-				      PCI_DEVICE_ID_QLOGIC_ISP12160, pdev);
-		if (pdev &&
-		    idd->idd_pdev->bus->number == pdev->bus->number &&
-		    3 == PCI_SLOT(pdev->devfn))
-			found = 1;
-		pci_dev_put(pdev);
-	} while (pdev && !found);
-	if (NULL != pdev)
-		return IOC4_VARIANT_IO9;
-
-	/* IO10: Look for a Vitesse VSC 7174 at the same bus and slot 3. */
-	pdev = NULL;
-	do {
-		pdev = pci_get_device(PCI_VENDOR_ID_VITESSE,
-				      PCI_DEVICE_ID_VITESSE_VSC7174, pdev);
-		if (pdev &&
-		    idd->idd_pdev->bus->number == pdev->bus->number &&
-		    3 == PCI_SLOT(pdev->devfn))
-			found = 1;
-		pci_dev_put(pdev);
-	} while (pdev && !found);
-	if (NULL != pdev)
-		return IOC4_VARIANT_IO10;
-
-	/* PCI-RT: No SCSI/SATA controller will be present */
-	return IOC4_VARIANT_PCI_RT;
-}
-
-/* Adds a new instance of an IOC4 card */
-static int
-ioc4_probe(struct pci_dev *pdev, const struct pci_device_id *pci_id)
-{
-	struct ioc4_driver_data *idd;
-	struct ioc4_submodule *is;
-	uint32_t pcmd;
-	int ret;
-
-	/* Enable IOC4 and take ownership of it */
-	if ((ret = pci_enable_device(pdev))) {
-		printk(KERN_WARNING
-		       "%s: Failed to enable IOC4 device for pci_dev %s.\n",
-		       __FUNCTION__, pci_name(pdev));
-		goto out;
-	}
-	pci_set_master(pdev);
-
-	/* Set up per-IOC4 data */
-	idd = kmalloc(sizeof(struct ioc4_driver_data), GFP_KERNEL);
-	if (!idd) {
-		printk(KERN_WARNING
-		       "%s: Failed to allocate IOC4 data for pci_dev %s.\n",
-		       __FUNCTION__, pci_name(pdev));
-		ret = -ENODEV;
-		goto out_idd;
-	}
-	idd->idd_pdev = pdev;
-	idd->idd_pci_id = pci_id;
-
-	/* Map IOC4 misc registers.  These are shared between subdevices
-	 * so the main IOC4 module manages them.
-	 */
-	idd->idd_bar0 = pci_resource_start(idd->idd_pdev, 0);
-	if (!idd->idd_bar0) {
-		printk(KERN_WARNING
-		       "%s: Unable to find IOC4 misc resource "
-		       "for pci_dev %s.\n",
-		       __FUNCTION__, pci_name(idd->idd_pdev));
-		ret = -ENODEV;
-		goto out_pci;
-	}
-	if (!request_region(idd->idd_bar0, sizeof(struct ioc4_misc_regs),
-			    "ioc4_misc")) {
-		printk(KERN_WARNING
-		       "%s: Unable to request IOC4 misc region "
-		       "for pci_dev %s.\n",
-		       __FUNCTION__, pci_name(idd->idd_pdev));
-		ret = -ENODEV;
-		goto out_pci;
-	}
-	idd->idd_misc_regs = ioremap(idd->idd_bar0,
-				     sizeof(struct ioc4_misc_regs));
-	if (!idd->idd_misc_regs) {
-		printk(KERN_WARNING
-		       "%s: Unable to remap IOC4 misc region "
-		       "for pci_dev %s.\n",
-		       __FUNCTION__, pci_name(idd->idd_pdev));
-		ret = -ENODEV;
-		goto out_misc_region;
-	}
-
-	/* Failsafe portion of per-IOC4 initialization */
-
-	/* Detect card variant */
-	idd->idd_variant = ioc4_variant(idd);
-	printk(KERN_INFO "IOC4 %s: %s card detected.\n", pci_name(pdev),
-	       idd->idd_variant == IOC4_VARIANT_IO9 ? "IO9" :
-	       idd->idd_variant == IOC4_VARIANT_PCI_RT ? "PCI-RT" :
-	       idd->idd_variant == IOC4_VARIANT_IO10 ? "IO10" : "unknown");
-
-	/* Initialize IOC4 */
-	pci_read_config_dword(idd->idd_pdev, PCI_COMMAND, &pcmd);
-	pci_write_config_dword(idd->idd_pdev, PCI_COMMAND,
-			       pcmd | PCI_COMMAND_PARITY | PCI_COMMAND_SERR);
-
-	/* Determine PCI clock */
-	ioc4_clock_calibrate(idd);
-
-	/* Disable/clear all interrupts.  Need to do this here lest
-	 * one submodule request the shared IOC4 IRQ, but interrupt
-	 * is generated by a different subdevice.
-	 */
-	/* Disable */
-	writel(~0, &idd->idd_misc_regs->other_iec.raw);
-	writel(~0, &idd->idd_misc_regs->sio_iec);
-	/* Clear (i.e. acknowledge) */
-	writel(~0, &idd->idd_misc_regs->other_ir.raw);
-	writel(~0, &idd->idd_misc_regs->sio_ir);
-
-	/* Track PCI-device specific data */
-	idd->idd_serial_data = NULL;
-	pci_set_drvdata(idd->idd_pdev, idd);
-
-	mutex_lock(&ioc4_mutex);
-	list_add_tail(&idd->idd_list, &ioc4_devices);
-
-	/* Add this IOC4 to all submodules */
-	list_for_each_entry(is, &ioc4_submodules, is_list) {
-		if (is->is_probe && is->is_probe(idd)) {
-			printk(KERN_WARNING
-			       "%s: IOC4 submodule 0x%s probe failed "
-			       "for pci_dev %s.\n",
-			       __FUNCTION__, module_name(is->is_owner),
-			       pci_name(idd->idd_pdev));
-		}
-	}
-	mutex_unlock(&ioc4_mutex);
-
-	return 0;
-
-out_misc_region:
-	release_region(idd->idd_bar0, sizeof(struct ioc4_misc_regs));
-out_pci:
-	kfree(idd);
-out_idd:
-	pci_disable_device(pdev);
-out:
-	return ret;
-}
-
-/* Removes a particular instance of an IOC4 card. */
-static void
-ioc4_remove(struct pci_dev *pdev)
-{
-	struct ioc4_submodule *is;
-	struct ioc4_driver_data *idd;
-
-	idd = pci_get_drvdata(pdev);
-
-	/* Remove this IOC4 from all submodules */
-	mutex_lock(&ioc4_mutex);
-	list_for_each_entry(is, &ioc4_submodules, is_list) {
-		if (is->is_remove && is->is_remove(idd)) {
-			printk(KERN_WARNING
-			       "%s: IOC4 submodule 0x%s remove failed "
-			       "for pci_dev %s.\n",
-			       __FUNCTION__, module_name(is->is_owner),
-			       pci_name(idd->idd_pdev));
-		}
-	}
-	mutex_unlock(&ioc4_mutex);
-
-	/* Release resources */
-	iounmap(idd->idd_misc_regs);
-	if (!idd->idd_bar0) {
-		printk(KERN_WARNING
-		       "%s: Unable to get IOC4 misc mapping for pci_dev %s. "
-		       "Device removal may be incomplete.\n",
-		       __FUNCTION__, pci_name(idd->idd_pdev));
-	}
-	release_region(idd->idd_bar0, sizeof(struct ioc4_misc_regs));
-
-	/* Disable IOC4 and relinquish */
-	pci_disable_device(pdev);
-
-	/* Remove and free driver data */
-	mutex_lock(&ioc4_mutex);
-	list_del(&idd->idd_list);
-	mutex_unlock(&ioc4_mutex);
-	kfree(idd);
-}
-
-static struct pci_device_id ioc4_id_table[] = {
-	{PCI_VENDOR_ID_SGI, PCI_DEVICE_ID_SGI_IOC4, PCI_ANY_ID,
-	 PCI_ANY_ID, 0x0b4000, 0xFFFFFF},
-	{0}
-};
-
-static struct pci_driver ioc4_driver = {
-	.name = "IOC4",
-	.id_table = ioc4_id_table,
-	.probe = ioc4_probe,
-	.remove = ioc4_remove,
-};
-
-MODULE_DEVICE_TABLE(pci, ioc4_id_table);
-
-/*********************
- * Module management *
- *********************/
-
-/* Module load */
-static int __devinit
-ioc4_init(void)
-{
-	return pci_register_driver(&ioc4_driver);
-}
-
-/* Module unload */
-static void __devexit
-ioc4_exit(void)
-{
-	pci_unregister_driver(&ioc4_driver);
-}
-
-module_init(ioc4_init);
-module_exit(ioc4_exit);
-
-MODULE_AUTHOR("Brent Casavant - Silicon Graphics, Inc. <bcasavan@sgi.com>");
-MODULE_DESCRIPTION("PCI driver master module for SGI IOC4 Base-IO Card");
-MODULE_LICENSE("GPL");
-
-EXPORT_SYMBOL(ioc4_register_submodule);
-EXPORT_SYMBOL(ioc4_unregister_submodule);