* Copyright (C) 2005 Silicon Graphics, Inc. All Rights Reserved.
*/
-/*
- * This file contains a shim driver for the IOC4 IDE and serial drivers.
+/* 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_common.h>
-#include <linux/ide.h>
+#include <linux/ioc4.h>
+#include <linux/mmtimer.h>
+#include <linux/rtc.h>
+#include <linux/mutex.h>
+#include <asm/sn/addrs.h>
+#include <asm/sn/clksupport.h>
+#include <asm/sn/shub_mmr.h>
+/***************
+ * Definitions *
+ ***************/
-static int __devinit
-ioc4_probe_one(struct pci_dev *pdev, const struct pci_device_id *pci_id)
+/* 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)
+{
+ extern unsigned long sn_rtc_cycles_per_second;
+ union ioc4_int_out int_out;
+ union ioc4_gpcr gpcr;
+ unsigned int state, last_state = 1;
+ uint64_t start = 0, 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();
+
+ printk(KERN_INFO
+ "%s: Calibrating PCI bus speed "
+ "for pci_dev %s ... ", __FUNCTION__, pci_name(idd->idd_pdev));
+ /* 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) {
+ end = rtc_time();
+ break;
+ } else if (count == IOC4_CALIBRATE_DISCARD)
+ start = rtc_time();
+ }
+ last_state = state;
+ } while (1);
+
+ /* Calculation rearranged to preserve intermediate precision.
+ * Logically:
+ * 1. "end - start" gives us number of RTC cycles over all the
+ * square wave cycles measured.
+ * 2. Divide by number of square wave cycles to get number of
+ * RTC cycles per 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
+ * number of RTC cycles per IOC4 INT_OUT count.
+ * 4. Divide by sn_rtc_cycles_per_second to get seconds per
+ * count.
+ * 5. Multiply by 1E9 to get nanoseconds per count.
+ */
+ period = ((end - start) * 1000000000) /
+ (IOC4_CALIBRATE_CYCLES * 2 * (IOC4_CALIBRATE_COUNT + 1)
+ * sn_rtc_cycles_per_second);
+
+ /* Bounds check the result. */
+ if (period > IOC4_CALIBRATE_LOW_LIMIT ||
+ period < IOC4_CALIBRATE_HIGH_LIMIT) {
+ printk("failed. Assuming PCI clock ticks are %d ns.\n",
+ IOC4_CALIBRATE_DEFAULT / IOC4_EXTINT_COUNT_DIVISOR);
+ period = IOC4_CALIBRATE_DEFAULT;
+ } else {
+ printk("succeeded. PCI clock ticks are %ld ns.\n",
+ 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;
+}
+
+/* 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 device with "
- "pci_dev 0x%p... returning\n",
- __FUNCTION__, (void *)pdev);
- return ret;
+ "%s: Failed to enable IOC4 device for pci_dev %s.\n",
+ __FUNCTION__, pci_name(pdev));
+ goto out;
}
pci_set_master(pdev);
- /* attach each sub-device */
- ret = ioc4_ide_attach_one(pdev, pci_id);
- if (ret)
- return ret;
- return ioc4_serial_attach_one(pdev, pci_id);
+ /* 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 */
+
+ /* 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;
}
-/* pci device struct */
-static struct pci_device_id ioc4_s_id_table[] = {
+/* 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}
};
-MODULE_DEVICE_TABLE(pci, ioc4_s_id_table);
-static struct pci_driver __devinitdata ioc4_s_driver = {
- .name = "IOC4",
- .id_table = ioc4_s_id_table,
- .probe = ioc4_probe_one,
+static struct pci_driver __devinitdata ioc4_driver = {
+ .name = "IOC4",
+ .id_table = ioc4_id_table,
+ .probe = ioc4_probe,
+ .remove = ioc4_remove,
};
-static int __devinit ioc4_detect(void)
+MODULE_DEVICE_TABLE(pci, ioc4_id_table);
+
+/*********************
+ * Module management *
+ *********************/
+
+/* Module load */
+static int __devinit
+ioc4_init(void)
{
- ioc4_serial_init();
+ return pci_register_driver(&ioc4_driver);
+}
- return pci_register_driver(&ioc4_s_driver);
+/* Module unload */
+static void __devexit
+ioc4_exit(void)
+{
+ pci_unregister_driver(&ioc4_driver);
}
-module_init(ioc4_detect);
-MODULE_AUTHOR("Pat Gefre - Silicon Graphics Inc. (SGI) <pfg@sgi.com>");
-MODULE_DESCRIPTION("PCI driver module for SGI IOC4 Base-IO Card");
+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);
git://git.onelab.eu / linux-2.6.git / blobdiff