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isci: fix interrupt disable 

There is a (dubious?) lost irq workaround in sci_controller_isr() that
effectively nullifies attempts to disable interrupts.  Until the
workaround can be re-evaluated add some infrastructure to prevent the
interrupt handler from inadvertantly re-enabling interrupts.

The failure mode was interrupts continuing to run after the driver had
been removed and its iomappings torn down.

Reported-by: Jacek Danecki <jacek.danecki@intel.com>
Tested-by: Jacek Danecki <jacek.danecki@intel.com>
[richard: clear remaining interrupts at the end of reset]
Acked-by: Richard Boyd <richard.g.boyd@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dan Williams 2012-03-01 17:06:24 -08:00
parent 50a92d9314
commit 2396a2650a
2 changed files with 27 additions and 13 deletions
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39
drivers/scsi/isci/host.c
View File

@ -192,22 +192,27 @@ static bool sci_controller_completion_queue_has_entries(struct isci_host *ihost)
static bool sci_controller_isr(struct isci_host *ihost)
{
if (sci_controller_completion_queue_has_entries(ihost)) {
if (sci_controller_completion_queue_has_entries(ihost))
return true;
} else {
/*
* we have a spurious interrupt it could be that we have already
* emptied the completion queue from a previous interrupt */
writel(SMU_ISR_COMPLETION, &ihost->smu_registers->interrupt_status);
/*
* There is a race in the hardware that could cause us not to be notified
* of an interrupt completion if we do not take this step. We will mask
* then unmask the interrupts so if there is another interrupt pending
* the clearing of the interrupt source we get the next interrupt message. */
/* we have a spurious interrupt it could be that we have already
* emptied the completion queue from a previous interrupt
* FIXME: really!?
*/
writel(SMU_ISR_COMPLETION, &ihost->smu_registers->interrupt_status);
/* There is a race in the hardware that could cause us not to be
* notified of an interrupt completion if we do not take this
* step. We will mask then unmask the interrupts so if there is
* another interrupt pending the clearing of the interrupt
* source we get the next interrupt message.
*/
spin_lock(&ihost->scic_lock);
if (test_bit(IHOST_IRQ_ENABLED, &ihost->flags)) {
writel(0xFF000000, &ihost->smu_registers->interrupt_mask);
writel(0, &ihost->smu_registers->interrupt_mask);
}
spin_unlock(&ihost->scic_lock);
return false;
}
@ -698,14 +703,15 @@ static u32 sci_controller_get_suggested_start_timeout(struct isci_host *ihost)
static void sci_controller_enable_interrupts(struct isci_host *ihost)
{
BUG_ON(ihost->smu_registers == NULL);
set_bit(IHOST_IRQ_ENABLED, &ihost->flags);
writel(0, &ihost->smu_registers->interrupt_mask);
}
void sci_controller_disable_interrupts(struct isci_host *ihost)
{
BUG_ON(ihost->smu_registers == NULL);
clear_bit(IHOST_IRQ_ENABLED, &ihost->flags);
writel(0xffffffff, &ihost->smu_registers->interrupt_mask);
readl(&ihost->smu_registers->interrupt_mask); /* flush */
}
static void sci_controller_enable_port_task_scheduler(struct isci_host *ihost)
@ -1318,7 +1324,9 @@ void isci_host_deinit(struct isci_host *ihost)
*/
writel(0, &ihost->scu_registers->peg0.sgpio.interface_control);
spin_lock_irq(&ihost->scic_lock);
sci_controller_reset(ihost);
spin_unlock_irq(&ihost->scic_lock);
/* Cancel any/all outstanding port timers */
for (i = 0; i < ihost->logical_port_entries; i++) {
@ -1605,6 +1613,9 @@ static void sci_controller_reset_hardware(struct isci_host *ihost)
/* The write to the UFQGP clears the UFQPR */
writel(0, &ihost->scu_registers->sdma.unsolicited_frame_get_pointer);
/* clear all interrupts */
writel(~SMU_INTERRUPT_STATUS_RESERVED_MASK, &ihost->smu_registers->interrupt_status);
}
static void sci_controller_resetting_state_enter(struct sci_base_state_machine *sm)
@ -2391,7 +2402,9 @@ int isci_host_init(struct isci_host *ihost)
int i, err;
enum sci_status status;
spin_lock_irq(&ihost->scic_lock);
status = sci_controller_construct(ihost, scu_base(ihost), smu_base(ihost));
spin_unlock_irq(&ihost->scic_lock);
if (status != SCI_SUCCESS) {
dev_err(&ihost->pdev->dev,
"%s: sci_controller_construct failed - status = %x\n",

1
drivers/scsi/isci/host.h
View File

@ -200,6 +200,7 @@ struct isci_host {
struct pci_dev *pdev;
#define IHOST_START_PENDING 0
#define IHOST_STOP_PENDING 1
#define IHOST_IRQ_ENABLED 2
unsigned long flags;
wait_queue_head_t eventq;
struct Scsi_Host *shost;