diff options
Diffstat (limited to 'drivers/block/rsxx/core.c')
| -rw-r--r-- | drivers/block/rsxx/core.c | 651 |
1 files changed, 651 insertions, 0 deletions
diff --git a/drivers/block/rsxx/core.c b/drivers/block/rsxx/core.c new file mode 100644 index 000000000000..f75219140e70 --- /dev/null +++ b/drivers/block/rsxx/core.c @@ -0,0 +1,651 @@ +/* +* Filename: core.c +* +* +* Authors: Joshua Morris <josh.h.morris@us.ibm.com> +* Philip Kelleher <pjk1939@linux.vnet.ibm.com> +* +* (C) Copyright 2013 IBM Corporation +* +* 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; either version 2 of the +* License, or (at your option) any later version. +* +* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +*/ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/reboot.h> +#include <linux/slab.h> +#include <linux/bitops.h> + +#include <linux/genhd.h> +#include <linux/idr.h> + +#include "rsxx_priv.h" +#include "rsxx_cfg.h" + +#define NO_LEGACY 0 + +MODULE_DESCRIPTION("IBM RamSan PCIe Flash SSD Device Driver"); +MODULE_AUTHOR("IBM <support@ramsan.com>"); +MODULE_LICENSE("GPL"); +MODULE_VERSION(DRIVER_VERSION); + +static unsigned int force_legacy = NO_LEGACY; +module_param(force_legacy, uint, 0444); +MODULE_PARM_DESC(force_legacy, "Force the use of legacy type PCI interrupts"); + +static DEFINE_IDA(rsxx_disk_ida); +static DEFINE_SPINLOCK(rsxx_ida_lock); + +/*----------------- Interrupt Control & Handling -------------------*/ +static void __enable_intr(unsigned int *mask, unsigned int intr) +{ + *mask |= intr; +} + +static void __disable_intr(unsigned int *mask, unsigned int intr) +{ + *mask &= ~intr; +} + +/* + * NOTE: Disabling the IER will disable the hardware interrupt. + * Disabling the ISR will disable the software handling of the ISR bit. + * + * Enable/Disable interrupt functions assume the card->irq_lock + * is held by the caller. + */ +void rsxx_enable_ier(struct rsxx_cardinfo *card, unsigned int intr) +{ + if (unlikely(card->halt)) + return; + + __enable_intr(&card->ier_mask, intr); + iowrite32(card->ier_mask, card->regmap + IER); +} + +void rsxx_disable_ier(struct rsxx_cardinfo *card, unsigned int intr) +{ + __disable_intr(&card->ier_mask, intr); + iowrite32(card->ier_mask, card->regmap + IER); +} + +void rsxx_enable_ier_and_isr(struct rsxx_cardinfo *card, + unsigned int intr) +{ + if (unlikely(card->halt)) + return; + + __enable_intr(&card->isr_mask, intr); + __enable_intr(&card->ier_mask, intr); + iowrite32(card->ier_mask, card->regmap + IER); +} +void rsxx_disable_ier_and_isr(struct rsxx_cardinfo *card, + unsigned int intr) +{ + __disable_intr(&card->isr_mask, intr); + __disable_intr(&card->ier_mask, intr); + iowrite32(card->ier_mask, card->regmap + IER); +} + +irqreturn_t rsxx_isr(int irq, void *pdata) +{ + struct rsxx_cardinfo *card = (struct rsxx_cardinfo *) pdata; + unsigned int isr; + int handled = 0; + int reread_isr; + int i; + + spin_lock(&card->irq_lock); + + do { + reread_isr = 0; + + isr = ioread32(card->regmap + ISR); + if (isr == 0xffffffff) { + /* + * A few systems seem to have an intermittent issue + * where PCI reads return all Fs, but retrying the read + * a little later will return as expected. + */ + dev_info(CARD_TO_DEV(card), + "ISR = 0xFFFFFFFF, retrying later\n"); + break; + } + + isr &= card->isr_mask; + if (!isr) + break; + + for (i = 0; i < card->n_targets; i++) { + if (isr & CR_INTR_DMA(i)) { + if (card->ier_mask & CR_INTR_DMA(i)) { + rsxx_disable_ier(card, CR_INTR_DMA(i)); + reread_isr = 1; + } + queue_work(card->ctrl[i].done_wq, + &card->ctrl[i].dma_done_work); + handled++; + } + } + + if (isr & CR_INTR_CREG) { + schedule_work(&card->creg_ctrl.done_work); + handled++; + } + + if (isr & CR_INTR_EVENT) { + schedule_work(&card->event_work); + rsxx_disable_ier_and_isr(card, CR_INTR_EVENT); + handled++; + } + } while (reread_isr); + + spin_unlock(&card->irq_lock); + + return handled ? IRQ_HANDLED : IRQ_NONE; +} + +/*----------------- Card Event Handler -------------------*/ +static void card_state_change(struct rsxx_cardinfo *card, + unsigned int new_state) +{ + int st; + + dev_info(CARD_TO_DEV(card), + "card state change detected.(%s -> %s)\n", + rsxx_card_state_to_str(card->state), + rsxx_card_state_to_str(new_state)); + + card->state = new_state; + + /* Don't attach DMA interfaces if the card has an invalid config */ + if (!card->config_valid) + return; + + switch (new_state) { + case CARD_STATE_RD_ONLY_FAULT: + dev_crit(CARD_TO_DEV(card), + "Hardware has entered read-only mode!\n"); + /* + * Fall through so the DMA devices can be attached and + * the user can attempt to pull off their data. + */ + case CARD_STATE_GOOD: + st = rsxx_get_card_size8(card, &card->size8); + if (st) + dev_err(CARD_TO_DEV(card), + "Failed attaching DMA devices\n"); + + if (card->config_valid) + set_capacity(card->gendisk, card->size8 >> 9); + break; + + case CARD_STATE_FAULT: + dev_crit(CARD_TO_DEV(card), + "Hardware Fault reported!\n"); + /* Fall through. */ + + /* Everything else, detach DMA interface if it's attached. */ + case CARD_STATE_SHUTDOWN: + case CARD_STATE_STARTING: + case CARD_STATE_FORMATTING: + case CARD_STATE_UNINITIALIZED: + case CARD_STATE_SHUTTING_DOWN: + /* + * dStroy is a term coined by marketing to represent the low level + * secure erase. + */ + case CARD_STATE_DSTROYING: + set_capacity(card->gendisk, 0); + break; + } +} + +static void card_event_handler(struct work_struct *work) +{ + struct rsxx_cardinfo *card; + unsigned int state; + unsigned long flags; + int st; + + card = container_of(work, struct rsxx_cardinfo, event_work); + + if (unlikely(card->halt)) + return; + + /* + * Enable the interrupt now to avoid any weird race conditions where a + * state change might occur while rsxx_get_card_state() is + * processing a returned creg cmd. + */ + spin_lock_irqsave(&card->irq_lock, flags); + rsxx_enable_ier_and_isr(card, CR_INTR_EVENT); + spin_unlock_irqrestore(&card->irq_lock, flags); + + st = rsxx_get_card_state(card, &state); + if (st) { + dev_info(CARD_TO_DEV(card), + "Failed reading state after event.\n"); + return; + } + + if (card->state != state) + card_state_change(card, state); + + if (card->creg_ctrl.creg_stats.stat & CREG_STAT_LOG_PENDING) + rsxx_read_hw_log(card); +} + + +char *rsxx_card_state_to_str(unsigned int state) +{ + static char *state_strings[] = { + "Unknown", "Shutdown", "Starting", "Formatting", + "Uninitialized", "Good", "Shutting Down", + "Fault", "Read Only Fault", "dStroying" + }; + + return state_strings[ffs(state)]; +} + +/*----------------- Card Operations -------------------*/ +static int card_shutdown(struct rsxx_cardinfo *card) +{ + unsigned int state; + signed long start; + const int timeout = msecs_to_jiffies(120000); + int st; + + /* We can't issue a shutdown if the card is in a transition state */ + start = jiffies; + do { + st = rsxx_get_card_state(card, &state); + if (st) + return st; + } while (state == CARD_STATE_STARTING && + (jiffies - start < timeout)); + + if (state == CARD_STATE_STARTING) + return -ETIMEDOUT; + + /* Only issue a shutdown if we need to */ + if ((state != CARD_STATE_SHUTTING_DOWN) && + (state != CARD_STATE_SHUTDOWN)) { + st = rsxx_issue_card_cmd(card, CARD_CMD_SHUTDOWN); + if (st) + return st; + } + + start = jiffies; + do { + st = rsxx_get_card_state(card, &state); + if (st) + return st; + } while (state != CARD_STATE_SHUTDOWN && + (jiffies - start < timeout)); + + if (state != CARD_STATE_SHUTDOWN) + return -ETIMEDOUT; + + return 0; +} + +/*----------------- Driver Initialization & Setup -------------------*/ +/* Returns: 0 if the driver is compatible with the device + -1 if the driver is NOT compatible with the device */ +static int rsxx_compatibility_check(struct rsxx_cardinfo *card) +{ + unsigned char pci_rev; + + pci_read_config_byte(card->dev, PCI_REVISION_ID, &pci_rev); + + if (pci_rev > RS70_PCI_REV_SUPPORTED) + return -1; + return 0; +} + +static int __devinit rsxx_pci_probe(struct pci_dev *dev, + const struct pci_device_id *id) +{ + struct rsxx_cardinfo *card; + unsigned long flags; + int st; + + dev_info(&dev->dev, "PCI-Flash SSD discovered\n"); + + card = kzalloc(sizeof(*card), GFP_KERNEL); + if (!card) + return -ENOMEM; + + card->dev = dev; + pci_set_drvdata(dev, card); + + do { + if (!ida_pre_get(&rsxx_disk_ida, GFP_KERNEL)) { + st = -ENOMEM; + goto failed_ida_get; + } + + spin_lock(&rsxx_ida_lock); + st = ida_get_new(&rsxx_disk_ida, &card->disk_id); + spin_unlock(&rsxx_ida_lock); + } while (st == -EAGAIN); + + if (st) + goto failed_ida_get; + + st = pci_enable_device(dev); + if (st) + goto failed_enable; + + pci_set_master(dev); + pci_set_dma_max_seg_size(dev, RSXX_HW_BLK_SIZE); + + st = pci_set_dma_mask(dev, DMA_BIT_MASK(64)); + if (st) { + dev_err(CARD_TO_DEV(card), + "No usable DMA configuration,aborting\n"); + goto failed_dma_mask; + } + + st = pci_request_regions(dev, DRIVER_NAME); + if (st) { + dev_err(CARD_TO_DEV(card), + "Failed to request memory region\n"); + goto failed_request_regions; + } + + if (pci_resource_len(dev, 0) == 0) { + dev_err(CARD_TO_DEV(card), "BAR0 has length 0!\n"); + st = -ENOMEM; + goto failed_iomap; + } + + card->regmap = pci_iomap(dev, 0, 0); + if (!card->regmap) { + dev_err(CARD_TO_DEV(card), "Failed to map BAR0\n"); + st = -ENOMEM; + goto failed_iomap; + } + + spin_lock_init(&card->irq_lock); + card->halt = 0; + + spin_lock_irqsave(&card->irq_lock, flags); + rsxx_disable_ier_and_isr(card, CR_INTR_ALL); + spin_unlock_irqrestore(&card->irq_lock, flags); + + if (!force_legacy) { + st = pci_enable_msi(dev); + if (st) + dev_warn(CARD_TO_DEV(card), + "Failed to enable MSI\n"); + } + + st = request_irq(dev->irq, rsxx_isr, IRQF_DISABLED | IRQF_SHARED, + DRIVER_NAME, card); + if (st) { + dev_err(CARD_TO_DEV(card), + "Failed requesting IRQ%d\n", dev->irq); + goto failed_irq; + } + + /************* Setup Processor Command Interface *************/ + rsxx_creg_setup(card); + + spin_lock_irqsave(&card->irq_lock, flags); + rsxx_enable_ier_and_isr(card, CR_INTR_CREG); + spin_unlock_irqrestore(&card->irq_lock, flags); + + st = rsxx_compatibility_check(card); + if (st) { + dev_warn(CARD_TO_DEV(card), + "Incompatible driver detected. Please update the driver.\n"); + st = -EINVAL; + goto failed_compatiblity_check; + } + + /************* Load Card Config *************/ + st = rsxx_load_config(card); + if (st) + dev_err(CARD_TO_DEV(card), + "Failed loading card config\n"); + + /************* Setup DMA Engine *************/ + st = rsxx_get_num_targets(card, &card->n_targets); + if (st) + dev_info(CARD_TO_DEV(card), + "Failed reading the number of DMA targets\n"); + + card->ctrl = kzalloc(card->n_targets * sizeof(*card->ctrl), GFP_KERNEL); + if (!card->ctrl) { + st = -ENOMEM; + goto failed_dma_setup; + } + + st = rsxx_dma_setup(card); + if (st) { + dev_info(CARD_TO_DEV(card), + "Failed to setup DMA engine\n"); + goto failed_dma_setup; + } + + /************* Setup Card Event Handler *************/ + INIT_WORK(&card->event_work, card_event_handler); + + st = rsxx_setup_dev(card); + if (st) + goto failed_create_dev; + + rsxx_get_card_state(card, &card->state); + + dev_info(CARD_TO_DEV(card), + "card state: %s\n", + rsxx_card_state_to_str(card->state)); + + /* + * Now that the DMA Engine and devices have been setup, + * we can enable the event interrupt(it kicks off actions in + * those layers so we couldn't enable it right away.) + */ + spin_lock_irqsave(&card->irq_lock, flags); + rsxx_enable_ier_and_isr(card, CR_INTR_EVENT); + spin_unlock_irqrestore(&card->irq_lock, flags); + + if (card->state == CARD_STATE_SHUTDOWN) { + st = rsxx_issue_card_cmd(card, CARD_CMD_STARTUP); + if (st) + dev_crit(CARD_TO_DEV(card), + "Failed issuing card startup\n"); + } else if (card->state == CARD_STATE_GOOD || + card->state == CARD_STATE_RD_ONLY_FAULT) { + st = rsxx_get_card_size8(card, &card->size8); + if (st) + card->size8 = 0; + } + + rsxx_attach_dev(card); + + return 0; + +failed_create_dev: + rsxx_dma_destroy(card); +failed_dma_setup: +failed_compatiblity_check: + spin_lock_irqsave(&card->irq_lock, flags); + rsxx_disable_ier_and_isr(card, CR_INTR_ALL); + spin_unlock_irqrestore(&card->irq_lock, flags); + free_irq(dev->irq, card); + if (!force_legacy) + pci_disable_msi(dev); +failed_irq: + pci_iounmap(dev, card->regmap); +failed_iomap: + pci_release_regions(dev); +failed_request_regions: +failed_dma_mask: + pci_disable_device(dev); +failed_enable: + spin_lock(&rsxx_ida_lock); + ida_remove(&rsxx_disk_ida, card->disk_id); + spin_unlock(&rsxx_ida_lock); +failed_ida_get: + kfree(card); + + return st; +} + +static void __devexit rsxx_pci_remove(struct pci_dev *dev) +{ + struct rsxx_cardinfo *card = pci_get_drvdata(dev); + unsigned long flags; + int st; + int i; + + if (!card) + return; + + dev_info(CARD_TO_DEV(card), + "Removing PCI-Flash SSD.\n"); + + rsxx_detach_dev(card); + + for (i = 0; i < card->n_targets; i++) { + spin_lock_irqsave(&card->irq_lock, flags); + rsxx_disable_ier_and_isr(card, CR_INTR_DMA(i)); + spin_unlock_irqrestore(&card->irq_lock, flags); + } + + st = card_shutdown(card); + if (st) + dev_crit(CARD_TO_DEV(card), "Shutdown failed!\n"); + + /* Sync outstanding event handlers. */ + spin_lock_irqsave(&card->irq_lock, flags); + rsxx_disable_ier_and_isr(card, CR_INTR_EVENT); + spin_unlock_irqrestore(&card->irq_lock, flags); + + /* Prevent work_structs from re-queuing themselves. */ + card->halt = 1; + + cancel_work_sync(&card->event_work); + + rsxx_destroy_dev(card); + rsxx_dma_destroy(card); + + spin_lock_irqsave(&card->irq_lock, flags); + rsxx_disable_ier_and_isr(card, CR_INTR_ALL); + spin_unlock_irqrestore(&card->irq_lock, flags); + free_irq(dev->irq, card); + + if (!force_legacy) + pci_disable_msi(dev); + + rsxx_creg_destroy(card); + + pci_iounmap(dev, card->regmap); + + pci_disable_device(dev); + pci_release_regions(dev); + + kfree(card); +} + +static int rsxx_pci_suspend(struct pci_dev *dev, pm_message_t state) +{ + /* We don't support suspend at this time. */ + return -ENOSYS; +} + +static void rsxx_pci_shutdown(struct pci_dev *dev) +{ + struct rsxx_cardinfo *card = pci_get_drvdata(dev); + unsigned long flags; + int i; + + if (!card) + return; + + dev_info(CARD_TO_DEV(card), "Shutting down PCI-Flash SSD.\n"); + + rsxx_detach_dev(card); + + for (i = 0; i < card->n_targets; i++) { + spin_lock_irqsave(&card->irq_lock, flags); + rsxx_disable_ier_and_isr(card, CR_INTR_DMA(i)); + spin_unlock_irqrestore(&card->irq_lock, flags); + } + + card_shutdown(card); +} + +static DEFINE_PCI_DEVICE_TABLE(rsxx_pci_ids) = { + {PCI_DEVICE(PCI_VENDOR_ID_TMS_IBM, PCI_DEVICE_ID_RS70_FLASH)}, + {PCI_DEVICE(PCI_VENDOR_ID_TMS_IBM, PCI_DEVICE_ID_RS70D_FLASH)}, + {PCI_DEVICE(PCI_VENDOR_ID_TMS_IBM, PCI_DEVICE_ID_RS80_FLASH)}, + {PCI_DEVICE(PCI_VENDOR_ID_TMS_IBM, PCI_DEVICE_ID_RS81_FLASH)}, + {0,}, +}; + +MODULE_DEVICE_TABLE(pci, rsxx_pci_ids); + +static struct pci_driver rsxx_pci_driver = { + .name = DRIVER_NAME, + .id_table = rsxx_pci_ids, + .probe = rsxx_pci_probe, + .remove = __devexit_p(rsxx_pci_remove), + .suspend = rsxx_pci_suspend, + .shutdown = rsxx_pci_shutdown, +}; + +static int __init rsxx_core_init(void) +{ + int st; + + st = rsxx_dev_init(); + if (st) + return st; + + st = rsxx_dma_init(); + if (st) + goto dma_init_failed; + + st = rsxx_creg_init(); + if (st) + goto creg_init_failed; + + return pci_register_driver(&rsxx_pci_driver); + +creg_init_failed: + rsxx_dma_cleanup(); +dma_init_failed: + rsxx_dev_cleanup(); + + return st; +} + +static void __exit rsxx_core_cleanup(void) +{ + pci_unregister_driver(&rsxx_pci_driver); + rsxx_creg_cleanup(); + rsxx_dma_cleanup(); + rsxx_dev_cleanup(); +} + +module_init(rsxx_core_init); +module_exit(rsxx_core_cleanup); |