ata: ahci_platform: Add shutdown handler

The newly introduced ahci_platform_shutdown() method is called during
system shutdown to disable host controller DMA and interrupts in order
to avoid potentially corrupting or otherwise interfering with a new
kernel being started with kexec.

Signed-off-by: Nate Watterson <nwatters@codeaurora.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Nate Watterson 2017-07-20 15:26:24 -04:00 committed by Tejun Heo
parent afbd39a42e
commit 8eede5bc4e
3 changed files with 37 additions and 0 deletions

View file

@ -93,6 +93,7 @@ MODULE_DEVICE_TABLE(acpi, ahci_acpi_match);
static struct platform_driver ahci_driver = {
.probe = ahci_probe,
.remove = ata_platform_remove_one,
.shutdown = ahci_platform_shutdown,
.driver = {
.name = DRV_NAME,
.of_match_table = ahci_of_match,

View file

@ -602,6 +602,40 @@ static void ahci_host_stop(struct ata_host *host)
ahci_platform_disable_resources(hpriv);
}
/**
* ahci_platform_shutdown - Disable interrupts and stop DMA for host ports
* @dev: platform device pointer for the host
*
* This function is called during system shutdown and performs the minimal
* deconfiguration required to ensure that an ahci_platform host cannot
* corrupt or otherwise interfere with a new kernel being started with kexec.
*/
void ahci_platform_shutdown(struct platform_device *pdev)
{
struct ata_host *host = platform_get_drvdata(pdev);
struct ahci_host_priv *hpriv = host->private_data;
void __iomem *mmio = hpriv->mmio;
int i;
for (i = 0; i < host->n_ports; i++) {
struct ata_port *ap = host->ports[i];
/* Disable port interrupts */
if (ap->ops->freeze)
ap->ops->freeze(ap);
/* Stop the port DMA engines */
if (ap->ops->port_stop)
ap->ops->port_stop(ap);
}
/* Disable and clear host interrupts */
writel(readl(mmio + HOST_CTL) & ~HOST_IRQ_EN, mmio + HOST_CTL);
readl(mmio + HOST_CTL); /* flush */
writel(GENMASK(host->n_ports, 0), mmio + HOST_IRQ_STAT);
}
EXPORT_SYMBOL_GPL(ahci_platform_shutdown);
#ifdef CONFIG_PM_SLEEP
/**
* ahci_platform_suspend_host - Suspend an ahci-platform host

View file

@ -36,6 +36,8 @@ int ahci_platform_init_host(struct platform_device *pdev,
const struct ata_port_info *pi_template,
struct scsi_host_template *sht);
void ahci_platform_shutdown(struct platform_device *pdev);
int ahci_platform_suspend_host(struct device *dev);
int ahci_platform_resume_host(struct device *dev);
int ahci_platform_suspend(struct device *dev);