Hi, all I send this out early to get feedback how to do ata port runtime pm. There was some discussion early this year trying to add runtime pm support to sata_mv controller driver. http://marc.info/?l=linux-ide&m=129403126729115&w=2 Here I focus on ata port runtime pm, not controller. In below conceptual patch, I did 0. Set autosuspend delay to 3 minutes for ata port 1. Split a new function ata_port_request_pm from ata_host_request_pm 2. Add device_type "ata_port_type" which implements callbacks for runtime pm core 3. Resume port in ata_scsi_queuecmd if needed 4. Request auto suspend in ata_scsi_queuecmd CAUTION: this patch DOES NOT work at all. I just threw it out for discussion. Any idea? Thanks. Lin Ming --- drivers/ata/libata-core.c | 126 +++++++++++++++++++++++++++++++++------------ drivers/ata/libata-scsi.c | 6 ++ 2 files changed, 99 insertions(+), 33 deletions(-) diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 4a3a5ae..e0c1a15 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -66,6 +66,7 @@ #include <asm/byteorder.h> #include <linux/cdrom.h> #include <linux/ratelimit.h> +#include <linux/pm_runtime.h> #include "libata.h" #include "libata-transport.h" @@ -5234,51 +5235,62 @@ bool ata_link_offline(struct ata_link *link) } #ifdef CONFIG_PM -static int ata_host_request_pm(struct ata_host *host, pm_message_t mesg, +static int ata_port_request_pm(struct ata_port *ap, pm_message_t mesg, unsigned int action, unsigned int ehi_flags, int wait) { + struct ata_link *link; unsigned long flags; - int i, rc; + int rc; - for (i = 0; i < host->n_ports; i++) { - struct ata_port *ap = host->ports[i]; - struct ata_link *link; + /* Previous resume operation might still be in + * progress. Wait for PM_PENDING to clear. + */ + if (ap->pflags & ATA_PFLAG_PM_PENDING) { + ata_port_wait_eh(ap); + WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING); + } - /* Previous resume operation might still be in - * progress. Wait for PM_PENDING to clear. - */ - if (ap->pflags & ATA_PFLAG_PM_PENDING) { - ata_port_wait_eh(ap); - WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING); - } + /* request PM ops to EH */ + spin_lock_irqsave(ap->lock, flags); - /* request PM ops to EH */ - spin_lock_irqsave(ap->lock, flags); + ap->pm_mesg = mesg; + if (wait) { + rc = 0; + ap->pm_result = &rc; + } - ap->pm_mesg = mesg; - if (wait) { - rc = 0; - ap->pm_result = &rc; - } + ap->pflags |= ATA_PFLAG_PM_PENDING; + ata_for_each_link(link, ap, HOST_FIRST) { + link->eh_info.action |= action; + link->eh_info.flags |= ehi_flags; + } - ap->pflags |= ATA_PFLAG_PM_PENDING; - ata_for_each_link(link, ap, HOST_FIRST) { - link->eh_info.action |= action; - link->eh_info.flags |= ehi_flags; - } + ata_port_schedule_eh(ap); - ata_port_schedule_eh(ap); + spin_unlock_irqrestore(ap->lock, flags); - spin_unlock_irqrestore(ap->lock, flags); + /* wait and check result */ + if (wait) { + ata_port_wait_eh(ap); + WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING); + } - /* wait and check result */ - if (wait) { - ata_port_wait_eh(ap); - WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING); - if (rc) - return rc; - } + return rc; +} + +static int ata_host_request_pm(struct ata_host *host, pm_message_t mesg, + unsigned int action, unsigned int ehi_flags, + int wait) +{ + int i, rc; + + for (i = 0; i < host->n_ports; i++) { + struct ata_port *ap = host->ports[i]; + + rc = ata_port_request_pm(ap, mesg, action, ehi_flags, wait); + if (rc) + return rc; } return 0; @@ -5874,6 +5886,45 @@ void ata_host_init(struct ata_host *host, struct device *dev, host->ops = ops; } +#define to_ata_port(d) container_of(d, struct ata_port, tdev) + +static int ata_port_runtime_suspend(struct device *dev) +{ + struct ata_port *ap = to_ata_port(dev); + struct Scsi_Host *shost = ap->scsi_host; + int rc; + + /* TODO: sync with hardware access */ + + if (shost->host_busy) + return -EBUSY; + + rc = ata_port_request_pm(ap, PMSG_SUSPEND, 0, ATA_EHI_QUIET, 1); + return rc; +} + +static int ata_port_runtime_resume(struct device *dev) +{ + struct ata_port *ap = to_ata_port(dev); + int rc; + + rc = ata_port_request_pm(ap, PMSG_ON, ATA_EH_RESET, + ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 1); + return rc; +} + +static const struct dev_pm_ops ata_port_pm_ops = { + .runtime_suspend = ata_port_runtime_suspend, + .runtime_resume = ata_port_runtime_resume, +}; + +static struct device_type ata_port_type = { + .name = "ata_port", +#ifdef CONFIG_PM + .pm = &ata_port_pm_ops, +#endif +}; + int ata_port_probe(struct ata_port *ap) { int rc = 0; @@ -5903,6 +5954,15 @@ int ata_port_probe(struct ata_port *ap) rc = ata_bus_probe(ap); DPRINTK("ata%u: bus probe end\n", ap->print_id); } + + ap->tdev.type = &ata_port_type; + pm_runtime_set_active(&ap->tdev); + pm_runtime_use_autosuspend(&ap->tdev); + /* 3 minutes idle to auto suspend */ + pm_runtime_set_autosuspend_delay(&ap->tdev, 180*1000); + pm_runtime_enable(&ap->tdev); + pm_request_autosuspend(&ap->tdev); + return rc; } diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index 46d087f..88fc7fe 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -48,6 +48,7 @@ #include <linux/hdreg.h> #include <linux/uaccess.h> #include <linux/suspend.h> +#include <linux/pm_runtime.h> #include <asm/unaligned.h> #include "libata.h" @@ -3208,6 +3209,11 @@ int ata_scsi_queuecmd(struct Scsi_Host *shost, struct scsi_cmnd *cmd) ap = ata_shost_to_port(shost); + if (pm_runtime_suspended(&ap->tdev)) + pm_runtime_resume(&ap->tdev); + pm_runtime_mark_last_busy(&ap->tdev); + pm_request_autosuspend(&ap->tdev); + spin_lock_irqsave(ap->lock, irq_flags); ata_scsi_dump_cdb(ap, cmd); -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
