diff options
Diffstat (limited to 'drivers/sn/ioc4.c')
| -rw-r--r-- | drivers/sn/ioc4.c | 427 |
1 files changed, 0 insertions, 427 deletions
diff --git a/drivers/sn/ioc4.c b/drivers/sn/ioc4.c deleted file mode 100644 index ea75b3d0612..00000000000 --- a/drivers/sn/ioc4.c +++ /dev/null @@ -1,427 +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 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/mmtimer.h> -#include <linux/rtc.h> -#include <linux/rwsem.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 LIST_HEAD(ioc4_devices); -static DECLARE_RWSEM(ioc4_devices_rwsem); - -static LIST_HEAD(ioc4_submodules); -static DECLARE_RWSEM(ioc4_submodules_rwsem); - -/* Register an IOC4 submodule */ -int -ioc4_register_submodule(struct ioc4_submodule *is) -{ - struct ioc4_driver_data *idd; - - down_write(&ioc4_submodules_rwsem); - list_add(&is->is_list, &ioc4_submodules); - up_write(&ioc4_submodules_rwsem); - - /* Initialize submodule for each IOC4 */ - if (!is->is_probe) - return 0; - - down_read(&ioc4_devices_rwsem); - 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)); - } - } - up_read(&ioc4_devices_rwsem); - - return 0; -} - -/* Unregister an IOC4 submodule */ -void -ioc4_unregister_submodule(struct ioc4_submodule *is) -{ - struct ioc4_driver_data *idd; - - down_write(&ioc4_submodules_rwsem); - list_del(&is->is_list); - up_write(&ioc4_submodules_rwsem); - - /* Remove submodule for each IOC4 */ - if (!is->is_remove) - return; - - down_read(&ioc4_devices_rwsem); - 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)); - } - } - up_read(&ioc4_devices_rwsem); -} - -/********************* - * 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 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 */ - - /* 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); - down_write(&ioc4_devices_rwsem); - list_add(&idd->idd_list, &ioc4_devices); - up_write(&ioc4_devices_rwsem); - - /* Add this IOC4 to all submodules */ - down_read(&ioc4_submodules_rwsem); - 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)); - } - } - up_read(&ioc4_submodules_rwsem); - - 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 */ - down_read(&ioc4_submodules_rwsem); - 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)); - } - } - up_read(&ioc4_submodules_rwsem); - - /* 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 */ - down_write(&ioc4_devices_rwsem); - list_del(&idd->idd_list); - up_write(&ioc4_devices_rwsem); - 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 __devinitdata 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); |