Device Initiated Power Management, which is defined
in SATA 2.5 can be enabled for disks which support it.
This patch enables DIPM when the user sets the link
power management policy to "min_power".
Additionally, libata drivers can define a function
(enable_pm) that will perform hardware specific actions to
enable whatever power management policy the user set up
for Host Initiated Power management (HIPM).
This power management policy will be activated after all
disks have been enumerated and intialized. Drivers should
also define disable_pm, which will turn off link power
management, but not change link power management policy.
Signed-off-by: Kristen Carlson Accardi <[email protected]>
---
Documentation/scsi/link_power_management_policy.txt | 19 +
drivers/ata/libata-core.c | 194 +++++++++++++++++++-
drivers/ata/libata-eh.c | 5
drivers/ata/libata-scsi.c | 83 ++++++++
include/linux/ata.h | 7
include/linux/libata.h | 25 ++
6 files changed, 322 insertions(+), 11 deletions(-)
Index: libata-dev/drivers/ata/libata-scsi.c
===================================================================
--- libata-dev.orig/drivers/ata/libata-scsi.c 2007-09-24 13:43:10.000000000 -0700
+++ libata-dev/drivers/ata/libata-scsi.c 2007-09-24 13:46:22.000000000 -0700
@@ -110,6 +110,78 @@ static struct scsi_transport_template at
};
+static const struct {
+ enum link_pm value;
+ char *name;
+} link_pm_policy[] = {
+ { NOT_AVAILABLE, "max_performance" },
+ { MIN_POWER, "min_power" },
+ { MAX_PERFORMANCE, "max_performance" },
+ { MEDIUM_POWER, "medium_power" },
+};
+
+const char *ata_scsi_link_pm_policy(enum link_pm policy)
+{
+ int i;
+ char *name = NULL;
+
+ for (i = 0; i < ARRAY_SIZE(link_pm_policy); i++) {
+ if (link_pm_policy[i].value == policy) {
+ name = link_pm_policy[i].name;
+ break;
+ }
+ }
+ return name;
+}
+
+static ssize_t store_link_pm_policy(struct class_device *class_dev,
+ const char *buf, size_t count)
+{
+ struct Scsi_Host *shost = class_to_shost(class_dev);
+ struct ata_port *ap = ata_shost_to_port(shost);
+ enum link_pm policy = 0;
+ int i;
+
+ /*
+ * we are skipping array location 0 on purpose - this
+ * is because a value of NOT_AVAILABLE is displayed
+ * to the user as max_performance, but when the user
+ * writes "max_performance", they actually want the
+ * value to match MAX_PERFORMANCE.
+ */
+ for (i = 1; i < ARRAY_SIZE(link_pm_policy); i++) {
+ const int len = strlen(link_pm_policy[i].name);
+ if (strncmp(link_pm_policy[i].name, buf, len) == 0 &&
+ buf[len] == '\n') {
+ policy = link_pm_policy[i].value;
+ break;
+ }
+ }
+ if (!policy)
+ return -EINVAL;
+
+ if (ata_scsi_set_link_pm_policy(ap, policy))
+ return -EINVAL;
+ return count;
+}
+
+static ssize_t
+show_link_pm_policy(struct class_device *class_dev, char *buf)
+{
+ struct Scsi_Host *shost = class_to_shost(class_dev);
+ struct ata_port *ap = ata_shost_to_port(shost);
+ const char *policy =
+ ata_scsi_link_pm_policy(ap->pm_policy);
+
+ if (!policy)
+ return -EINVAL;
+
+ return snprintf(buf, 23, "%s\n", policy);
+}
+CLASS_DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
+ show_link_pm_policy, store_link_pm_policy);
+EXPORT_SYMBOL_GPL(class_device_attr_link_power_management_policy);
+
static void ata_scsi_invalid_field(struct scsi_cmnd *cmd,
void (*done)(struct scsi_cmnd *))
{
@@ -3041,6 +3113,17 @@ void ata_scsi_simulate(struct ata_device
}
}
+int ata_scsi_set_link_pm_policy(struct ata_port *ap,
+ enum link_pm policy)
+{
+ ap->pm_policy = policy;
+ ap->link.eh_info.action |= ATA_EHI_LPM;
+ ap->link.eh_info.flags |= ATA_EHI_NO_AUTOPSY;
+ ata_port_schedule_eh(ap);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ata_scsi_set_link_pm_policy);
+
int ata_scsi_add_hosts(struct ata_host *host, struct scsi_host_template *sht)
{
int i, rc;
Index: libata-dev/include/linux/libata.h
===================================================================
--- libata-dev.orig/include/linux/libata.h 2007-09-24 13:43:10.000000000 -0700
+++ libata-dev/include/linux/libata.h 2007-09-24 13:47:57.000000000 -0700
@@ -140,6 +140,8 @@ enum {
ATA_DFLAG_ACPI_PENDING = (1 << 5), /* ACPI resume action pending */
ATA_DFLAG_ACPI_FAILED = (1 << 6), /* ACPI on devcfg has failed */
ATA_DFLAG_AN = (1 << 7), /* device supports AN */
+ ATA_DFLAG_HIPM = (1 << 8), /* device supports HIPM */
+ ATA_DFLAG_DIPM = (1 << 9), /* device supports DIPM */
ATA_DFLAG_CFG_MASK = (1 << 12) - 1,
ATA_DFLAG_PIO = (1 << 12), /* device limited to PIO mode */
@@ -181,6 +183,7 @@ enum {
ATA_FLAG_NO_IORDY = (1 << 16), /* controller lacks iordy */
ATA_FLAG_ACPI_SATA = (1 << 17), /* need native SATA ACPI layout */
ATA_FLAG_AN = (1 << 18), /* controller supports AN */
+ ATA_FLAG_IPM = (1 << 19), /* driver can handle IPM */
/* The following flag belongs to ap->pflags but is kept in
* ap->flags because it's referenced in many LLDs and will be
@@ -283,6 +286,7 @@ enum {
ATA_EHI_RESUME_LINK = (1 << 1), /* resume link (reset modifier) */
ATA_EHI_NO_AUTOPSY = (1 << 2), /* no autopsy */
ATA_EHI_QUIET = (1 << 3), /* be quiet */
+ ATA_EHI_LPM = (1 << 4), /* link power management action */
ATA_EHI_DID_SOFTRESET = (1 << 16), /* already soft-reset this port */
ATA_EHI_DID_HARDRESET = (1 << 17), /* already soft-reset this port */
@@ -308,6 +312,7 @@ enum {
ATA_HORKAGE_NONCQ = (1 << 2), /* Don't use NCQ */
ATA_HORKAGE_MAX_SEC_128 = (1 << 3), /* Limit max sects to 128 */
ATA_HORKAGE_BROKEN_HPA = (1 << 4), /* Broken HPA */
+ ATA_HORKAGE_IPM = (1 << 5), /* LPM problems */
};
enum hsm_task_states {
@@ -347,6 +352,18 @@ typedef int (*ata_reset_fn_t)(struct ata
unsigned long deadline);
typedef void (*ata_postreset_fn_t)(struct ata_link *link, unsigned int *classes);
+/*
+ * host pm policy: If you alter this, you also need to alter libata-scsi.c
+ * (for the ascii descriptions)
+ */
+enum link_pm {
+ NOT_AVAILABLE,
+ MIN_POWER,
+ MAX_PERFORMANCE,
+ MEDIUM_POWER,
+};
+extern struct class_device_attribute class_device_attr_link_power_management_policy;
+
struct ata_ioports {
void __iomem *cmd_addr;
void __iomem *data_addr;
@@ -585,6 +602,7 @@ struct ata_port {
pm_message_t pm_mesg;
int *pm_result;
+ enum link_pm pm_policy;
struct timer_list fastdrain_timer;
unsigned long fastdrain_cnt;
@@ -647,7 +665,8 @@ struct ata_port_operations {
int (*port_suspend) (struct ata_port *ap, pm_message_t mesg);
int (*port_resume) (struct ata_port *ap);
-
+ int (*enable_pm) (struct ata_port *ap, enum link_pm policy);
+ int (*disable_pm) (struct ata_port *ap);
int (*port_start) (struct ata_port *ap);
void (*port_stop) (struct ata_port *ap);
@@ -854,7 +873,9 @@ extern int ata_cable_40wire(struct ata_p
extern int ata_cable_80wire(struct ata_port *ap);
extern int ata_cable_sata(struct ata_port *ap);
extern int ata_cable_unknown(struct ata_port *ap);
-
+extern int ata_scsi_set_link_pm_policy(struct ata_port *ap, enum link_pm);
+extern int ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy);
+extern void ata_dev_disable_pm(struct ata_device *dev);
/*
* Timing helpers
*/
Index: libata-dev/drivers/ata/libata-core.c
===================================================================
--- libata-dev.orig/drivers/ata/libata-core.c 2007-09-24 13:43:10.000000000 -0700
+++ libata-dev/drivers/ata/libata-core.c 2007-09-24 13:46:22.000000000 -0700
@@ -68,7 +68,8 @@ const unsigned long sata_deb_timing_long
static unsigned int ata_dev_init_params(struct ata_device *dev,
u16 heads, u16 sectors);
static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
-static unsigned int ata_dev_set_AN(struct ata_device *dev, u8 enable);
+static unsigned int ata_dev_set_feature(struct ata_device *dev,
+ u8 enable, u8 feature);
static void ata_dev_xfermask(struct ata_device *dev);
static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
@@ -615,6 +616,129 @@ void ata_dev_disable(struct ata_device *
}
}
+static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
+{
+ struct ata_link *link = dev->link;
+ struct ata_port *ap = link->ap;
+ u32 scontrol;
+
+ /*
+ * disallow DIPM for drivers which haven't set
+ * ATA_FLAG_IPM. This is because when DIPM is enabled,
+ * phy ready will be set in the interrupt status on
+ * state changes, which will cause some drivers to
+ * think there are errors - additionally drivers will
+ * need to disable hot plug.
+ */
+ if (!(ap->flags & ATA_FLAG_IPM) || !ata_dev_enabled(dev)) {
+ ap->pm_policy = NOT_AVAILABLE;
+ return -EINVAL;
+ }
+
+ /*
+ * For DIPM, we will only enable it for the
+ * min_power setting.
+ *
+ * Why? Because Disks are too stupid to know that
+ * If the host rejects a request to go to SLUMBER
+ * they should retry at PARTIAL, and instead it
+ * just would give up. So, for medium_power to
+ * work at all, we need to only allow HIPM.
+ */
+ sata_scr_read(link, SCR_CONTROL, &scontrol);
+
+ switch (policy) {
+ case MIN_POWER:
+ /* no restrictions on IPM transitions */
+ scontrol &= ~(0x3 << 8);
+ sata_scr_write(link, SCR_CONTROL, scontrol);
+
+ /* enable DIPM */
+ if (dev->flags & ATA_DFLAG_DIPM)
+ ata_dev_set_feature(dev, SETFEATURES_SATA_ENABLE,
+ SATA_DIPM);
+ break;
+ case MEDIUM_POWER:
+ /* allow IPM to PARTIAL */
+ scontrol &= ~(0x1 << 8);
+ scontrol |= (0x2 << 8);
+ sata_scr_write(link, SCR_CONTROL, scontrol);
+
+ /* disable DIPM */
+ if (ata_dev_enabled(dev) && (dev->flags & ATA_DFLAG_DIPM))
+ ata_dev_set_feature(dev, SETFEATURES_SATA_DISABLE,
+ SATA_DIPM);
+ break;
+ case NOT_AVAILABLE:
+ case MAX_PERFORMANCE:
+ /* disable all IPM transitions */
+ scontrol |= (0x3 << 8);
+ sata_scr_write(link, SCR_CONTROL, scontrol);
+
+ /* disable DIPM */
+ if (ata_dev_enabled(dev) && (dev->flags & ATA_DFLAG_DIPM))
+ ata_dev_set_feature(dev, SETFEATURES_SATA_DISABLE,
+ SATA_DIPM);
+ break;
+ }
+ return 0;
+}
+
+/**
+ * ata_dev_enable_pm - enable SATA interface power management
+ * @device - device to enable ipm for
+ * @policy - the link power management policy
+ *
+ * Enable SATA Interface power management. This will enable
+ * Device Interface Power Management (DIPM) for min_power
+ * policy, and then call driver specific callbacks for
+ * enabling Host Initiated Power management.
+ *
+ * Locking: Caller.
+ * Returns: -EINVAL if IPM is not supported, 0 otherwise.
+ */
+int ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy)
+{
+ int rc = 0;
+ struct ata_port *ap = dev->link->ap;
+
+ /* set HIPM first, then DIPM */
+ if (ap->ops->enable_pm)
+ rc = ap->ops->enable_pm(ap, policy);
+ if (rc)
+ goto enable_pm_out;
+ rc = ata_dev_set_dipm(dev, policy);
+
+enable_pm_out:
+ if (rc)
+ ap->pm_policy = MAX_PERFORMANCE;
+ else
+ ap->pm_policy = policy;
+ return rc;
+}
+
+/**
+ * ata_dev_disable_pm - disable SATA interface power management
+ * @device - device to enable ipm for
+ *
+ * Disable SATA Interface power management. This will disable
+ * Device Interface Power Management (DIPM) without changing
+ * policy, call driver specific callbacks for disabling Host
+ * Initiated Power management.
+ *
+ * Locking: Caller.
+ * Returns: void
+ */
+void ata_dev_disable_pm(struct ata_device *dev)
+{
+ struct ata_port *ap = dev->link->ap;
+
+ ata_dev_set_dipm(dev, MAX_PERFORMANCE);
+ if (ap->ops->disable_pm)
+ ap->ops->disable_pm(ap);
+}
+
+
/**
* ata_devchk - PATA device presence detection
* @ap: ATA channel to examine
@@ -2029,7 +2153,8 @@ int ata_dev_configure(struct ata_device
if ((ap->flags & ATA_FLAG_AN) && ata_id_has_AN(id)) {
int err;
/* issue SET feature command to turn this on */
- err = ata_dev_set_AN(dev, SETFEATURES_SATA_ENABLE);
+ err = ata_dev_set_feature(dev, SETFEATURES_SATA_ENABLE,
+ SATA_AN);
if (err)
ata_dev_printk(dev, KERN_ERR,
"unable to set AN, err %x\n",
@@ -2057,6 +2182,13 @@ int ata_dev_configure(struct ata_device
if (dev->flags & ATA_DFLAG_LBA48)
dev->max_sectors = ATA_MAX_SECTORS_LBA48;
+ if (!(dev->horkage & ATA_HORKAGE_IPM)) {
+ if (ata_id_has_hipm(dev->id))
+ dev->flags |= ATA_DFLAG_HIPM;
+ if (ata_id_has_dipm(dev->id))
+ dev->flags |= ATA_DFLAG_DIPM;
+ }
+
if (dev->horkage & ATA_HORKAGE_DIAGNOSTIC) {
/* Let the user know. We don't want to disallow opens for
rescue purposes, or in case the vendor is just a blithering
@@ -2082,6 +2214,13 @@ int ata_dev_configure(struct ata_device
dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
dev->max_sectors);
+ if (ata_dev_blacklisted(dev) & ATA_HORKAGE_IPM) {
+ dev->horkage |= ATA_HORKAGE_IPM;
+
+ /* reset link pm_policy for this port to no pm */
+ ap->pm_policy = MAX_PERFORMANCE;
+ }
+
if (ap->ops->dev_config)
ap->ops->dev_config(dev);
@@ -4048,15 +4187,14 @@ static unsigned int ata_dev_set_xfermode
DPRINTK("EXIT, err_mask=%x\n", err_mask);
return err_mask;
}
-
/**
- * ata_dev_set_AN - Issue SET FEATURES - SATA FEATURES
+ * ata_dev_set_feature - Issue SET FEATURES - SATA FEATURES
* @dev: Device to which command will be sent
* @enable: Whether to enable or disable the feature
+ * @feature: The sector count represents the feature to set
*
* Issue SET FEATURES - SATA FEATURES command to device @dev
- * on port @ap with sector count set to indicate Asynchronous
- * Notification feature
+ * on port @ap with sector count
*
* LOCKING:
* PCI/etc. bus probe sem.
@@ -4064,7 +4202,8 @@ static unsigned int ata_dev_set_xfermode
* RETURNS:
* 0 on success, AC_ERR_* mask otherwise.
*/
-static unsigned int ata_dev_set_AN(struct ata_device *dev, u8 enable)
+static unsigned int ata_dev_set_feature(struct ata_device *dev, u8 enable,
+ u8 feature)
{
struct ata_taskfile tf;
unsigned int err_mask;
@@ -4077,7 +4216,7 @@ static unsigned int ata_dev_set_AN(struc
tf.feature = enable;
tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
tf.protocol = ATA_PROT_NODATA;
- tf.nsect = SATA_AN;
+ tf.nsect = feature;
err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0);
@@ -6031,6 +6170,32 @@ int ata_flush_cache(struct ata_device *d
return 0;
}
+static void ata_host_disable_link_pm(struct ata_host *host)
+{
+ int i;
+ struct ata_link *link;
+ struct ata_port *ap;
+ struct ata_device *dev;
+
+ for (i = 0; i < host->n_ports; i++) {
+ ap = host->ports[i];
+ ata_port_for_each_link(link, ap) {
+ ata_link_for_each_dev(dev, link)
+ ata_dev_disable_pm(dev);
+ }
+ }
+}
+
+static void ata_host_enable_link_pm(struct ata_host *host)
+{
+ int i;
+
+ for (i = 0; i < host->n_ports; i++) {
+ struct ata_port *ap = host->ports[i];
+ ata_scsi_set_link_pm_policy(ap, ap->pm_policy);
+ }
+}
+
#ifdef CONFIG_PM
static int ata_host_request_pm(struct ata_host *host, pm_message_t mesg,
unsigned int action, unsigned int ehi_flags,
@@ -6101,6 +6266,12 @@ int ata_host_suspend(struct ata_host *ho
{
int rc;
+ /*
+ * disable link pm on all ports before requesting
+ * any pm activity
+ */
+ ata_host_disable_link_pm(host);
+
rc = ata_host_request_pm(host, mesg, 0, ATA_EHI_QUIET, 1);
if (rc == 0)
host->dev->power.power_state = mesg;
@@ -6123,6 +6294,9 @@ void ata_host_resume(struct ata_host *ho
ata_host_request_pm(host, PMSG_ON, ATA_EH_SOFTRESET,
ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
host->dev->power.power_state = PMSG_ON;
+
+ /* reenable link pm */
+ ata_host_enable_link_pm(host);
}
#endif
@@ -6663,6 +6837,7 @@ int ata_host_register(struct ata_host *h
struct ata_port *ap = host->ports[i];
ata_scsi_scan_host(ap, 1);
+ ata_scsi_set_link_pm_policy(ap, ap->pm_policy);
}
return 0;
@@ -7059,7 +7234,8 @@ const struct ata_port_info ata_dummy_por
* likely to change as new drivers are added and updated.
* Do not depend on ABI/API stability.
*/
-
+EXPORT_SYMBOL_GPL(ata_dev_enable_pm);
+EXPORT_SYMBOL_GPL(ata_dev_disable_pm);
EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
EXPORT_SYMBOL_GPL(sata_deb_timing_long);
Index: libata-dev/include/linux/ata.h
===================================================================
--- libata-dev.orig/include/linux/ata.h 2007-09-24 13:43:10.000000000 -0700
+++ libata-dev/include/linux/ata.h 2007-09-24 13:46:22.000000000 -0700
@@ -235,6 +235,7 @@ enum {
/* SETFEATURE Sector counts for SATA features */
SATA_AN = 0x05, /* Asynchronous Notification */
+ SATA_DIPM = 0x03, /* Device Initiated Power Management */
/* ATAPI stuff */
ATAPI_PKT_DMA = (1 << 0),
@@ -367,6 +368,12 @@ struct ata_taskfile {
((u64) (id)[(n) + 0]) )
#define ata_id_cdb_intr(id) (((id)[0] & 0x60) == 0x20)
+#define ata_id_has_hipm(id) \
+ ( (((id)[76] != 0x0000) && ((id)[76] != 0xffff)) && \
+ ((id)[76] & (1 << 9)) )
+#define ata_id_has_dipm(id) \
+ ( (((id)[76] != 0x0000) && ((id)[76] != 0xffff)) && \
+ ((id)[78] & (1 << 3)) )
static inline int ata_id_has_fua(const u16 *id)
{
Index: libata-dev/Documentation/scsi/link_power_management_policy.txt
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ libata-dev/Documentation/scsi/link_power_management_policy.txt 2007-09-24 13:46:22.000000000 -0700
@@ -0,0 +1,19 @@
+This parameter allows the user to set the link (interface) power management.
+There are 3 possible options:
+
+Value Effect
+----------------------------------------------------------------------------
+min_power Tell the controller to try to make the link use the
+ least possible power when possible. This may
+ sacrifice some performance due to increased latency
+ when coming out of lower power states.
+
+max_performance Generally, this means no power management. Tell
+ the controller to have performance be a priority
+ over power management.
+
+medium_power Tell the controller to enter a lower power state
+ when possible, but do not enter the lowest power
+ state, thus improving latency over min_power setting.
+
+
Index: libata-dev/drivers/ata/libata-eh.c
===================================================================
--- libata-dev.orig/drivers/ata/libata-eh.c 2007-09-24 13:43:10.000000000 -0700
+++ libata-dev/drivers/ata/libata-eh.c 2007-09-24 13:46:22.000000000 -0700
@@ -2400,6 +2400,11 @@ static int ata_eh_recover(struct ata_por
ehc->i.flags &= ~ATA_EHI_SETMODE;
}
+ if (ehc->i.action & ATA_EHI_LPM) {
+ ata_link_for_each_dev(dev, link)
+ ata_dev_enable_pm(dev, ap->pm_policy);
+ }
+
/* this link is okay now */
ehc->i.flags = 0;
continue;
--
Kristen Carlson Accardi wrote:
> Device Initiated Power Management, which is defined
> in SATA 2.5 can be enabled for disks which support it.
> This patch enables DIPM when the user sets the link
> power management policy to "min_power".
>
> Additionally, libata drivers can define a function
> (enable_pm) that will perform hardware specific actions to
> enable whatever power management policy the user set up
> for Host Initiated Power management (HIPM).
> This power management policy will be activated after all
> disks have been enumerated and intialized. Drivers should
> also define disable_pm, which will turn off link power
> management, but not change link power management policy.
>
> Signed-off-by: Kristen Carlson Accardi <[email protected]>
> ---
> Documentation/scsi/link_power_management_policy.txt | 19 +
> drivers/ata/libata-core.c | 194 +++++++++++++++++++-
> drivers/ata/libata-eh.c | 5
> drivers/ata/libata-scsi.c | 83 ++++++++
> include/linux/ata.h | 7
> include/linux/libata.h | 25 ++
> 6 files changed, 322 insertions(+), 11 deletions(-)
>
> Index: libata-dev/drivers/ata/libata-scsi.c
> ===================================================================
> --- libata-dev.orig/drivers/ata/libata-scsi.c 2007-09-24 13:43:10.000000000 -0700
> +++ libata-dev/drivers/ata/libata-scsi.c 2007-09-24 13:46:22.000000000 -0700
> @@ -110,6 +110,78 @@ static struct scsi_transport_template at
> };
>
>
> +static const struct {
> + enum link_pm value;
> + char *name;
> +} link_pm_policy[] = {
> + { NOT_AVAILABLE, "max_performance" },
> + { MIN_POWER, "min_power" },
> + { MAX_PERFORMANCE, "max_performance" },
> + { MEDIUM_POWER, "medium_power" },
> +};
> +
> +const char *ata_scsi_link_pm_policy(enum link_pm policy)
> +{
> + int i;
> + char *name = NULL;
> +
> + for (i = 0; i < ARRAY_SIZE(link_pm_policy); i++) {
> + if (link_pm_policy[i].value == policy) {
> + name = link_pm_policy[i].name;
> + break;
> + }
> + }
> + return name;
> +}
> +
> +static ssize_t store_link_pm_policy(struct class_device *class_dev,
> + const char *buf, size_t count)
> +{
> + struct Scsi_Host *shost = class_to_shost(class_dev);
> + struct ata_port *ap = ata_shost_to_port(shost);
> + enum link_pm policy = 0;
> + int i;
> +
> + /*
> + * we are skipping array location 0 on purpose - this
> + * is because a value of NOT_AVAILABLE is displayed
> + * to the user as max_performance, but when the user
> + * writes "max_performance", they actually want the
> + * value to match MAX_PERFORMANCE.
> + */
> + for (i = 1; i < ARRAY_SIZE(link_pm_policy); i++) {
> + const int len = strlen(link_pm_policy[i].name);
> + if (strncmp(link_pm_policy[i].name, buf, len) == 0 &&
> + buf[len] == '\n') {
> + policy = link_pm_policy[i].value;
> + break;
> + }
> + }
> + if (!policy)
> + return -EINVAL;
> +
> + if (ata_scsi_set_link_pm_policy(ap, policy))
> + return -EINVAL;
> + return count;
> +}
> +
> +static ssize_t
> +show_link_pm_policy(struct class_device *class_dev, char *buf)
> +{
> + struct Scsi_Host *shost = class_to_shost(class_dev);
> + struct ata_port *ap = ata_shost_to_port(shost);
> + const char *policy =
> + ata_scsi_link_pm_policy(ap->pm_policy);
> +
> + if (!policy)
> + return -EINVAL;
> +
> + return snprintf(buf, 23, "%s\n", policy);
> +}
> +CLASS_DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
> + show_link_pm_policy, store_link_pm_policy);
> +EXPORT_SYMBOL_GPL(class_device_attr_link_power_management_policy);
> +
> static void ata_scsi_invalid_field(struct scsi_cmnd *cmd,
> void (*done)(struct scsi_cmnd *))
> {
> @@ -3041,6 +3113,17 @@ void ata_scsi_simulate(struct ata_device
> }
> }
>
> +int ata_scsi_set_link_pm_policy(struct ata_port *ap,
> + enum link_pm policy)
> +{
> + ap->pm_policy = policy;
> + ap->link.eh_info.action |= ATA_EHI_LPM;
> + ap->link.eh_info.flags |= ATA_EHI_NO_AUTOPSY;
> + ata_port_schedule_eh(ap);
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(ata_scsi_set_link_pm_policy);
> +
> int ata_scsi_add_hosts(struct ata_host *host, struct scsi_host_template *sht)
> {
> int i, rc;
> Index: libata-dev/include/linux/libata.h
> ===================================================================
> --- libata-dev.orig/include/linux/libata.h 2007-09-24 13:43:10.000000000 -0700
> +++ libata-dev/include/linux/libata.h 2007-09-24 13:47:57.000000000 -0700
> @@ -140,6 +140,8 @@ enum {
> ATA_DFLAG_ACPI_PENDING = (1 << 5), /* ACPI resume action pending */
> ATA_DFLAG_ACPI_FAILED = (1 << 6), /* ACPI on devcfg has failed */
> ATA_DFLAG_AN = (1 << 7), /* device supports AN */
> + ATA_DFLAG_HIPM = (1 << 8), /* device supports HIPM */
> + ATA_DFLAG_DIPM = (1 << 9), /* device supports DIPM */
> ATA_DFLAG_CFG_MASK = (1 << 12) - 1,
>
> ATA_DFLAG_PIO = (1 << 12), /* device limited to PIO mode */
> @@ -181,6 +183,7 @@ enum {
> ATA_FLAG_NO_IORDY = (1 << 16), /* controller lacks iordy */
> ATA_FLAG_ACPI_SATA = (1 << 17), /* need native SATA ACPI layout */
> ATA_FLAG_AN = (1 << 18), /* controller supports AN */
> + ATA_FLAG_IPM = (1 << 19), /* driver can handle IPM */
>
> /* The following flag belongs to ap->pflags but is kept in
> * ap->flags because it's referenced in many LLDs and will be
> @@ -283,6 +286,7 @@ enum {
> ATA_EHI_RESUME_LINK = (1 << 1), /* resume link (reset modifier) */
> ATA_EHI_NO_AUTOPSY = (1 << 2), /* no autopsy */
> ATA_EHI_QUIET = (1 << 3), /* be quiet */
> + ATA_EHI_LPM = (1 << 4), /* link power management action */
>
> ATA_EHI_DID_SOFTRESET = (1 << 16), /* already soft-reset this port */
> ATA_EHI_DID_HARDRESET = (1 << 17), /* already soft-reset this port */
> @@ -308,6 +312,7 @@ enum {
> ATA_HORKAGE_NONCQ = (1 << 2), /* Don't use NCQ */
> ATA_HORKAGE_MAX_SEC_128 = (1 << 3), /* Limit max sects to 128 */
> ATA_HORKAGE_BROKEN_HPA = (1 << 4), /* Broken HPA */
> + ATA_HORKAGE_IPM = (1 << 5), /* LPM problems */
> };
>
> enum hsm_task_states {
> @@ -347,6 +352,18 @@ typedef int (*ata_reset_fn_t)(struct ata
> unsigned long deadline);
> typedef void (*ata_postreset_fn_t)(struct ata_link *link, unsigned int *classes);
>
> +/*
> + * host pm policy: If you alter this, you also need to alter libata-scsi.c
> + * (for the ascii descriptions)
> + */
> +enum link_pm {
> + NOT_AVAILABLE,
> + MIN_POWER,
> + MAX_PERFORMANCE,
> + MEDIUM_POWER,
> +};
> +extern struct class_device_attribute class_device_attr_link_power_management_policy;
> +
> struct ata_ioports {
> void __iomem *cmd_addr;
> void __iomem *data_addr;
> @@ -585,6 +602,7 @@ struct ata_port {
>
> pm_message_t pm_mesg;
> int *pm_result;
> + enum link_pm pm_policy;
>
> struct timer_list fastdrain_timer;
> unsigned long fastdrain_cnt;
> @@ -647,7 +665,8 @@ struct ata_port_operations {
>
> int (*port_suspend) (struct ata_port *ap, pm_message_t mesg);
> int (*port_resume) (struct ata_port *ap);
> -
> + int (*enable_pm) (struct ata_port *ap, enum link_pm policy);
> + int (*disable_pm) (struct ata_port *ap);
> int (*port_start) (struct ata_port *ap);
> void (*port_stop) (struct ata_port *ap);
>
> @@ -854,7 +873,9 @@ extern int ata_cable_40wire(struct ata_p
> extern int ata_cable_80wire(struct ata_port *ap);
> extern int ata_cable_sata(struct ata_port *ap);
> extern int ata_cable_unknown(struct ata_port *ap);
> -
> +extern int ata_scsi_set_link_pm_policy(struct ata_port *ap, enum link_pm);
> +extern int ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy);
> +extern void ata_dev_disable_pm(struct ata_device *dev);
> /*
> * Timing helpers
> */
> Index: libata-dev/drivers/ata/libata-core.c
> ===================================================================
> --- libata-dev.orig/drivers/ata/libata-core.c 2007-09-24 13:43:10.000000000 -0700
> +++ libata-dev/drivers/ata/libata-core.c 2007-09-24 13:46:22.000000000 -0700
> @@ -68,7 +68,8 @@ const unsigned long sata_deb_timing_long
> static unsigned int ata_dev_init_params(struct ata_device *dev,
> u16 heads, u16 sectors);
> static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
> -static unsigned int ata_dev_set_AN(struct ata_device *dev, u8 enable);
> +static unsigned int ata_dev_set_feature(struct ata_device *dev,
> + u8 enable, u8 feature);
> static void ata_dev_xfermask(struct ata_device *dev);
> static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
>
> @@ -615,6 +616,129 @@ void ata_dev_disable(struct ata_device *
> }
> }
>
> +static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
> +{
> + struct ata_link *link = dev->link;
> + struct ata_port *ap = link->ap;
> + u32 scontrol;
> +
> + /*
> + * disallow DIPM for drivers which haven't set
> + * ATA_FLAG_IPM. This is because when DIPM is enabled,
> + * phy ready will be set in the interrupt status on
> + * state changes, which will cause some drivers to
> + * think there are errors - additionally drivers will
> + * need to disable hot plug.
> + */
> + if (!(ap->flags & ATA_FLAG_IPM) || !ata_dev_enabled(dev)) {
if (!((ap->flags & ATA_FLAG_IPM) && ata_dev_enabled(dev))) {
> + ap->pm_policy = NOT_AVAILABLE;
> + return -EINVAL;
> + }
> +
> + /*
> + * For DIPM, we will only enable it for the
> + * min_power setting.
> + *
> + * Why? Because Disks are too stupid to know that
> + * If the host rejects a request to go to SLUMBER
> + * they should retry at PARTIAL, and instead it
> + * just would give up. So, for medium_power to
> + * work at all, we need to only allow HIPM.
> + */
> + sata_scr_read(link, SCR_CONTROL, &scontrol);
> +
> + switch (policy) {
> + case MIN_POWER:
> + /* no restrictions on IPM transitions */
> + scontrol &= ~(0x3 << 8);
> + sata_scr_write(link, SCR_CONTROL, scontrol);
> +
> + /* enable DIPM */
> + if (dev->flags & ATA_DFLAG_DIPM)
> + ata_dev_set_feature(dev, SETFEATURES_SATA_ENABLE,
> + SATA_DIPM);
> + break;
> + case MEDIUM_POWER:
> + /* allow IPM to PARTIAL */
> + scontrol &= ~(0x1 << 8);
> + scontrol |= (0x2 << 8);
> + sata_scr_write(link, SCR_CONTROL, scontrol);
> +
> + /* disable DIPM */
> + if (ata_dev_enabled(dev) && (dev->flags & ATA_DFLAG_DIPM))
> + ata_dev_set_feature(dev, SETFEATURES_SATA_DISABLE,
> + SATA_DIPM);
> + break;
> + case NOT_AVAILABLE:
> + case MAX_PERFORMANCE:
> + /* disable all IPM transitions */
> + scontrol |= (0x3 << 8);
> + sata_scr_write(link, SCR_CONTROL, scontrol);
> +
> + /* disable DIPM */
> + if (ata_dev_enabled(dev) && (dev->flags & ATA_DFLAG_DIPM))
> + ata_dev_set_feature(dev, SETFEATURES_SATA_DISABLE,
> + SATA_DIPM);
> + break;
> + }
> + return 0;
> +}
> +
> +/**
> + * ata_dev_enable_pm - enable SATA interface power management
> + * @device - device to enable ipm for
> + * @policy - the link power management policy
> + *
> + * Enable SATA Interface power management. This will enable
> + * Device Interface Power Management (DIPM) for min_power
> + * policy, and then call driver specific callbacks for
> + * enabling Host Initiated Power management.
> + *
> + * Locking: Caller.
> + * Returns: -EINVAL if IPM is not supported, 0 otherwise.
> + */
> +int ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy)
> +{
> + int rc = 0;
> + struct ata_port *ap = dev->link->ap;
> +
> + /* set HIPM first, then DIPM */
> + if (ap->ops->enable_pm)
> + rc = ap->ops->enable_pm(ap, policy);
> + if (rc)
> + goto enable_pm_out;
> + rc = ata_dev_set_dipm(dev, policy);
> +
> +enable_pm_out:
> + if (rc)
> + ap->pm_policy = MAX_PERFORMANCE;
> + else
> + ap->pm_policy = policy;
> + return rc;
> +}
> +
> +/**
> + * ata_dev_disable_pm - disable SATA interface power management
> + * @device - device to enable ipm for
> + *
> + * Disable SATA Interface power management. This will disable
> + * Device Interface Power Management (DIPM) without changing
> + * policy, call driver specific callbacks for disabling Host
> + * Initiated Power management.
> + *
> + * Locking: Caller.
> + * Returns: void
> + */
> +void ata_dev_disable_pm(struct ata_device *dev)
> +{
> + struct ata_port *ap = dev->link->ap;
> +
> + ata_dev_set_dipm(dev, MAX_PERFORMANCE);
> + if (ap->ops->disable_pm)
> + ap->ops->disable_pm(ap);
> +}
> +
> +
> /**
> * ata_devchk - PATA device presence detection
> * @ap: ATA channel to examine
> @@ -2029,7 +2153,8 @@ int ata_dev_configure(struct ata_device
> if ((ap->flags & ATA_FLAG_AN) && ata_id_has_AN(id)) {
> int err;
> /* issue SET feature command to turn this on */
> - err = ata_dev_set_AN(dev, SETFEATURES_SATA_ENABLE);
> + err = ata_dev_set_feature(dev, SETFEATURES_SATA_ENABLE,
> + SATA_AN);
> if (err)
> ata_dev_printk(dev, KERN_ERR,
> "unable to set AN, err %x\n",
> @@ -2057,6 +2182,13 @@ int ata_dev_configure(struct ata_device
> if (dev->flags & ATA_DFLAG_LBA48)
> dev->max_sectors = ATA_MAX_SECTORS_LBA48;
>
> + if (!(dev->horkage & ATA_HORKAGE_IPM)) {
> + if (ata_id_has_hipm(dev->id))
> + dev->flags |= ATA_DFLAG_HIPM;
> + if (ata_id_has_dipm(dev->id))
> + dev->flags |= ATA_DFLAG_DIPM;
> + }
> +
> if (dev->horkage & ATA_HORKAGE_DIAGNOSTIC) {
> /* Let the user know. We don't want to disallow opens for
> rescue purposes, or in case the vendor is just a blithering
> @@ -2082,6 +2214,13 @@ int ata_dev_configure(struct ata_device
> dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
> dev->max_sectors);
>
> + if (ata_dev_blacklisted(dev) & ATA_HORKAGE_IPM) {
> + dev->horkage |= ATA_HORKAGE_IPM;
> +
> + /* reset link pm_policy for this port to no pm */
> + ap->pm_policy = MAX_PERFORMANCE;
> + }
> +
> if (ap->ops->dev_config)
> ap->ops->dev_config(dev);
>
> @@ -4048,15 +4187,14 @@ static unsigned int ata_dev_set_xfermode
> DPRINTK("EXIT, err_mask=%x\n", err_mask);
> return err_mask;
> }
> -
> /**
> - * ata_dev_set_AN - Issue SET FEATURES - SATA FEATURES
> + * ata_dev_set_feature - Issue SET FEATURES - SATA FEATURES
> * @dev: Device to which command will be sent
> * @enable: Whether to enable or disable the feature
> + * @feature: The sector count represents the feature to set
> *
> * Issue SET FEATURES - SATA FEATURES command to device @dev
> - * on port @ap with sector count set to indicate Asynchronous
> - * Notification feature
> + * on port @ap with sector count
> *
> * LOCKING:
> * PCI/etc. bus probe sem.
> @@ -4064,7 +4202,8 @@ static unsigned int ata_dev_set_xfermode
> * RETURNS:
> * 0 on success, AC_ERR_* mask otherwise.
> */
> -static unsigned int ata_dev_set_AN(struct ata_device *dev, u8 enable)
> +static unsigned int ata_dev_set_feature(struct ata_device *dev, u8 enable,
> + u8 feature)
> {
> struct ata_taskfile tf;
> unsigned int err_mask;
> @@ -4077,7 +4216,7 @@ static unsigned int ata_dev_set_AN(struc
> tf.feature = enable;
> tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
> tf.protocol = ATA_PROT_NODATA;
> - tf.nsect = SATA_AN;
> + tf.nsect = feature;
>
> err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0);
>
> @@ -6031,6 +6170,32 @@ int ata_flush_cache(struct ata_device *d
> return 0;
> }
>
> +static void ata_host_disable_link_pm(struct ata_host *host)
> +{
> + int i;
> + struct ata_link *link;
> + struct ata_port *ap;
> + struct ata_device *dev;
> +
> + for (i = 0; i < host->n_ports; i++) {
> + ap = host->ports[i];
> + ata_port_for_each_link(link, ap) {
> + ata_link_for_each_dev(dev, link)
> + ata_dev_disable_pm(dev);
> + }
> + }
> +}
> +
> +static void ata_host_enable_link_pm(struct ata_host *host)
> +{
> + int i;
> +
> + for (i = 0; i < host->n_ports; i++) {
> + struct ata_port *ap = host->ports[i];
> + ata_scsi_set_link_pm_policy(ap, ap->pm_policy);
> + }
> +}
> +
> #ifdef CONFIG_PM
> static int ata_host_request_pm(struct ata_host *host, pm_message_t mesg,
> unsigned int action, unsigned int ehi_flags,
> @@ -6101,6 +6266,12 @@ int ata_host_suspend(struct ata_host *ho
> {
> int rc;
>
> + /*
> + * disable link pm on all ports before requesting
> + * any pm activity
> + */
> + ata_host_disable_link_pm(host);
> +
> rc = ata_host_request_pm(host, mesg, 0, ATA_EHI_QUIET, 1);
> if (rc == 0)
> host->dev->power.power_state = mesg;
> @@ -6123,6 +6294,9 @@ void ata_host_resume(struct ata_host *ho
> ata_host_request_pm(host, PMSG_ON, ATA_EH_SOFTRESET,
> ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
> host->dev->power.power_state = PMSG_ON;
> +
> + /* reenable link pm */
> + ata_host_enable_link_pm(host);
> }
> #endif
>
> @@ -6663,6 +6837,7 @@ int ata_host_register(struct ata_host *h
> struct ata_port *ap = host->ports[i];
>
> ata_scsi_scan_host(ap, 1);
> + ata_scsi_set_link_pm_policy(ap, ap->pm_policy);
> }
>
> return 0;
> @@ -7059,7 +7234,8 @@ const struct ata_port_info ata_dummy_por
> * likely to change as new drivers are added and updated.
> * Do not depend on ABI/API stability.
> */
> -
> +EXPORT_SYMBOL_GPL(ata_dev_enable_pm);
> +EXPORT_SYMBOL_GPL(ata_dev_disable_pm);
> EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
> EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
> EXPORT_SYMBOL_GPL(sata_deb_timing_long);
> Index: libata-dev/include/linux/ata.h
> ===================================================================
> --- libata-dev.orig/include/linux/ata.h 2007-09-24 13:43:10.000000000 -0700
> +++ libata-dev/include/linux/ata.h 2007-09-24 13:46:22.000000000 -0700
> @@ -235,6 +235,7 @@ enum {
>
> /* SETFEATURE Sector counts for SATA features */
> SATA_AN = 0x05, /* Asynchronous Notification */
> + SATA_DIPM = 0x03, /* Device Initiated Power Management */
>
> /* ATAPI stuff */
> ATAPI_PKT_DMA = (1 << 0),
> @@ -367,6 +368,12 @@ struct ata_taskfile {
> ((u64) (id)[(n) + 0]) )
>
> #define ata_id_cdb_intr(id) (((id)[0] & 0x60) == 0x20)
> +#define ata_id_has_hipm(id) \
> + ( (((id)[76] != 0x0000) && ((id)[76] != 0xffff)) && \
> + ((id)[76] & (1 << 9)) )
^
|
are you sure this
should be 76?
we can also change the first statement a bit:
(!(((id)[76] == 0x0000) || ((id)[76] == 0xffff)) && \
> +#define ata_id_has_dipm(id) \
> + ( (((id)[76] != 0x0000) && ((id)[76] != 0xffff)) && \
and:
(!(((id)[76] == 0x0000) || ((id)[76] == 0xffff)) && \
> + ((id)[78] & (1 << 3)) )
>
> static inline int ata_id_has_fua(const u16 *id)
> {
> Index: libata-dev/Documentation/scsi/link_power_management_policy.txt
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ libata-dev/Documentation/scsi/link_power_management_policy.txt 2007-09-24 13:46:22.000000000 -0700
> @@ -0,0 +1,19 @@
> +This parameter allows the user to set the link (interface) power management.
> +There are 3 possible options:
> +
> +Value Effect
> +----------------------------------------------------------------------------
> +min_power Tell the controller to try to make the link use the
> + least possible power when possible. This may
> + sacrifice some performance due to increased latency
> + when coming out of lower power states.
> +
> +max_performance Generally, this means no power management. Tell
> + the controller to have performance be a priority
> + over power management.
> +
> +medium_power Tell the controller to enter a lower power state
> + when possible, but do not enter the lowest power
> + state, thus improving latency over min_power setting.
> +
> +
> Index: libata-dev/drivers/ata/libata-eh.c
> ===================================================================
> --- libata-dev.orig/drivers/ata/libata-eh.c 2007-09-24 13:43:10.000000000 -0700
> +++ libata-dev/drivers/ata/libata-eh.c 2007-09-24 13:46:22.000000000 -0700
> @@ -2400,6 +2400,11 @@ static int ata_eh_recover(struct ata_por
> ehc->i.flags &= ~ATA_EHI_SETMODE;
> }
>
> + if (ehc->i.action & ATA_EHI_LPM) {
> + ata_link_for_each_dev(dev, link)
> + ata_dev_enable_pm(dev, ap->pm_policy);
> + }
> +
> /* this link is okay now */
> ehc->i.flags = 0;
> continue;
>
On Tue, 25 Sep 2007, roel wrote:
> > + if (!(ap->flags & ATA_FLAG_IPM) || !ata_dev_enabled(dev)) {
>
> if (!((ap->flags & ATA_FLAG_IPM) && ata_dev_enabled(dev))) {
int foo(int i, int j) {
return !(i & 8) || !j;
}
int moo(int i, int j) {
return !((i & 8) && j);
}
gcc -O2 -S:
.globl foo
.type foo, @function
foo:
shrl $3, %edi
xorl $1, %edi
testl %esi, %esi
sete %al
orl %eax, %edi
andl $1, %edi
movl %edi, %eax
ret
.globl moo
.type moo, @function
moo:
shrl $3, %edi
xorl $1, %edi
testl %esi, %esi
sete %al
orl %eax, %edi
andl $1, %edi
movl %edi, %eax
ret
- Davide
On Tue, 25 Sep 2007 01:12:32 +0200
roel <[email protected]> wrote:
> > #define ata_id_cdb_intr(id) (((id)[0] & 0x60) == 0x20)
> > +#define ata_id_has_hipm(id) \
> > + ( (((id)[76] != 0x0000) && ((id)[76] != 0xffff)) && \
> > + ((id)[76] & (1 << 9)) )
> ^
> |
> are you sure this
> should be 76?
Yes.
>
> we can also change the first statement a bit:
> (!(((id)[76] == 0x0000) || ((id)[76] == 0xffff)) && \
>
>
> > +#define ata_id_has_dipm(id) \
> > + ( (((id)[76] != 0x0000) && ((id)[76] != 0xffff)) && \
>
> and:
> (!(((id)[76] == 0x0000) || ((id)[76] == 0xffff)) && \
I feel this is equivalent functionality and not as readable.
Kristen Carlson Accardi wrote:
> On Tue, 25 Sep 2007 01:12:32 +0200
> roel <[email protected]> wrote:
>
>>> #define ata_id_cdb_intr(id) (((id)[0] & 0x60) == 0x20)
>>> +#define ata_id_has_hipm(id) \
>>> + ( (((id)[76] != 0x0000) && ((id)[76] != 0xffff)) && \
>>> + ((id)[76] & (1 << 9)) )
>> ^
>> |
>> are you sure this
>> should be 76?
>
> Yes.
>
>> we can also change the first statement a bit:
>> (!(((id)[76] == 0x0000) || ((id)[76] == 0xffff)) && \
>>
>>
>>> +#define ata_id_has_dipm(id) \
>>> + ( (((id)[76] != 0x0000) && ((id)[76] != 0xffff)) && \
>> and:
>> (!(((id)[76] == 0x0000) || ((id)[76] == 0xffff)) && \
>
> I feel this is equivalent functionality and not as readable.
Poke around for Alan Cox's cleanup of this area of linux/ata.h.
It converts several macros to inline functions (encouraged), and also
illustrates a nice, clean way of testing an ID word's validity.
[obviously the final implementation varies, depending on that ID word's
history]
Alan or Andrew, got a copy somewhere? My feeble search skills don't
seem to turn it up at the moment, even though I had a copy in my hands
quite recently.
Jeff
Davide Libenzi wrote:
> On Tue, 25 Sep 2007, roel wrote:
>
>>> + if (!(ap->flags & ATA_FLAG_IPM) || !ata_dev_enabled(dev)) {
>> if (!((ap->flags & ATA_FLAG_IPM) && ata_dev_enabled(dev))) {
>
> int foo(int i, int j) {
>
> return !(i & 8) || !j;
> }
>
> int moo(int i, int j) {
>
> return !((i & 8) && j);
> }
>
>
> gcc -O2 -S:
>
>
> .globl foo
> .type foo, @function
> foo:
> shrl $3, %edi
> xorl $1, %edi
> testl %esi, %esi
> sete %al
> orl %eax, %edi
> andl $1, %edi
> movl %edi, %eax
> ret
> .globl moo
> .type moo, @function
> moo:
> shrl $3, %edi
> xorl $1, %edi
> testl %esi, %esi
> sete %al
> orl %eax, %edi
> andl $1, %edi
> movl %edi, %eax
> ret
Indeed, no difference, except for the eye.
do you not consider it an improvement or do you not want to change it?
or
don't you consider it an improvement and want to change it?
Never mind. Disregard if you please.
> - Davide
> It converts several macros to inline functions (encouraged), and also
> illustrates a nice, clean way of testing an ID word's validity.
> [obviously the final implementation varies, depending on that ID word's
> history]
Its in -mm and I thought you put a copy in your tree after I said it
hadn't upset anything in -mm ?
Alan
Alan Cox wrote:
>> It converts several macros to inline functions (encouraged), and also
>> illustrates a nice, clean way of testing an ID word's validity.
>> [obviously the final implementation varies, depending on that ID word's
>> history]
>
> Its in -mm and I thought you put a copy in your tree after I said it
> hadn't upset anything in -mm ?
it didn't apply straightaway to my tree for whatever reason, IIRC
commit 01fdf95f877e2a3f767248a5896e08a9e8787971
Author: Kristen Carlson Accardi <[email protected]>
Date: Thu Oct 25 00:58:59 2007 -0400
[libata] Link power management infrastructure
Device Initiated Power Management, which is defined
in SATA 2.5 can be enabled for disks which support it.
This patch enables DIPM when the user sets the link
power management policy to "min_power".
Additionally, libata drivers can define a function
(enable_pm) that will perform hardware specific actions to
enable whatever power management policy the user set up
for Host Initiated Power management (HIPM).
This power management policy will be activated after all
disks have been enumerated and intialized. Drivers should
also define disable_pm, which will turn off link power
management, but not change link power management policy.
Documentation/scsi/link_power_management_policy.txt has additional
information.
Signed-off-by: Kristen Carlson Accardi <[email protected]>
Signed-off-by: Jeff Garzik <[email protected]>
Documentation/scsi/link_power_management_policy.txt | 19 +
drivers/ata/libata-core.c | 196 +++++++++++++++++++-
drivers/ata/libata-eh.c | 4
drivers/ata/libata-scsi.c | 68 ++++++
drivers/ata/libata.h | 2
include/linux/ata.h | 21 ++
include/linux/libata.h | 21 ++
7 files changed, 329 insertions(+), 2 deletions(-)
01fdf95f877e2a3f767248a5896e08a9e8787971
diff --git a/Documentation/scsi/link_power_management_policy.txt b/Documentation/scsi/link_power_management_policy.txt
new file mode 100644
index 0000000..d18993d
--- /dev/null
+++ b/Documentation/scsi/link_power_management_policy.txt
@@ -0,0 +1,19 @@
+This parameter allows the user to set the link (interface) power management.
+There are 3 possible options:
+
+Value Effect
+----------------------------------------------------------------------------
+min_power Tell the controller to try to make the link use the
+ least possible power when possible. This may
+ sacrifice some performance due to increased latency
+ when coming out of lower power states.
+
+max_performance Generally, this means no power management. Tell
+ the controller to have performance be a priority
+ over power management.
+
+medium_power Tell the controller to enter a lower power state
+ when possible, but do not enter the lowest power
+ state, thus improving latency over min_power setting.
+
+
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 294eee3..a89ab56 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -620,6 +620,177 @@ void ata_dev_disable(struct ata_device *dev)
}
}
+static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
+{
+ struct ata_link *link = dev->link;
+ struct ata_port *ap = link->ap;
+ u32 scontrol;
+ unsigned int err_mask;
+ int rc;
+
+ /*
+ * disallow DIPM for drivers which haven't set
+ * ATA_FLAG_IPM. This is because when DIPM is enabled,
+ * phy ready will be set in the interrupt status on
+ * state changes, which will cause some drivers to
+ * think there are errors - additionally drivers will
+ * need to disable hot plug.
+ */
+ if (!(ap->flags & ATA_FLAG_IPM) || !ata_dev_enabled(dev)) {
+ ap->pm_policy = NOT_AVAILABLE;
+ return -EINVAL;
+ }
+
+ /*
+ * For DIPM, we will only enable it for the
+ * min_power setting.
+ *
+ * Why? Because Disks are too stupid to know that
+ * If the host rejects a request to go to SLUMBER
+ * they should retry at PARTIAL, and instead it
+ * just would give up. So, for medium_power to
+ * work at all, we need to only allow HIPM.
+ */
+ rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
+ if (rc)
+ return rc;
+
+ switch (policy) {
+ case MIN_POWER:
+ /* no restrictions on IPM transitions */
+ scontrol &= ~(0x3 << 8);
+ rc = sata_scr_write(link, SCR_CONTROL, scontrol);
+ if (rc)
+ return rc;
+
+ /* enable DIPM */
+ if (dev->flags & ATA_DFLAG_DIPM)
+ err_mask = ata_dev_set_feature(dev,
+ SETFEATURES_SATA_ENABLE, SATA_DIPM);
+ break;
+ case MEDIUM_POWER:
+ /* allow IPM to PARTIAL */
+ scontrol &= ~(0x1 << 8);
+ scontrol |= (0x2 << 8);
+ rc = sata_scr_write(link, SCR_CONTROL, scontrol);
+ if (rc)
+ return rc;
+
+ /* disable DIPM */
+ if (ata_dev_enabled(dev) && (dev->flags & ATA_DFLAG_DIPM))
+ err_mask = ata_dev_set_feature(dev,
+ SETFEATURES_SATA_DISABLE, SATA_DIPM);
+ break;
+ case NOT_AVAILABLE:
+ case MAX_PERFORMANCE:
+ /* disable all IPM transitions */
+ scontrol |= (0x3 << 8);
+ rc = sata_scr_write(link, SCR_CONTROL, scontrol);
+ if (rc)
+ return rc;
+
+ /* disable DIPM */
+ if (ata_dev_enabled(dev) && (dev->flags & ATA_DFLAG_DIPM))
+ err_mask = ata_dev_set_feature(dev,
+ SETFEATURES_SATA_DISABLE, SATA_DIPM);
+ break;
+ }
+
+ /* FIXME: handle SET FEATURES failure */
+ (void) err_mask;
+
+ return 0;
+}
+
+/**
+ * ata_dev_enable_pm - enable SATA interface power management
+ * @device - device to enable ipm for
+ * @policy - the link power management policy
+ *
+ * Enable SATA Interface power management. This will enable
+ * Device Interface Power Management (DIPM) for min_power
+ * policy, and then call driver specific callbacks for
+ * enabling Host Initiated Power management.
+ *
+ * Locking: Caller.
+ * Returns: -EINVAL if IPM is not supported, 0 otherwise.
+ */
+void ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy)
+{
+ int rc = 0;
+ struct ata_port *ap = dev->link->ap;
+
+ /* set HIPM first, then DIPM */
+ if (ap->ops->enable_pm)
+ rc = ap->ops->enable_pm(ap, policy);
+ if (rc)
+ goto enable_pm_out;
+ rc = ata_dev_set_dipm(dev, policy);
+
+enable_pm_out:
+ if (rc)
+ ap->pm_policy = MAX_PERFORMANCE;
+ else
+ ap->pm_policy = policy;
+ return /* rc */; /* hopefully we can use 'rc' eventually */
+}
+
+/**
+ * ata_dev_disable_pm - disable SATA interface power management
+ * @device - device to enable ipm for
+ *
+ * Disable SATA Interface power management. This will disable
+ * Device Interface Power Management (DIPM) without changing
+ * policy, call driver specific callbacks for disabling Host
+ * Initiated Power management.
+ *
+ * Locking: Caller.
+ * Returns: void
+ */
+static void ata_dev_disable_pm(struct ata_device *dev)
+{
+ struct ata_port *ap = dev->link->ap;
+
+ ata_dev_set_dipm(dev, MAX_PERFORMANCE);
+ if (ap->ops->disable_pm)
+ ap->ops->disable_pm(ap);
+}
+
+void ata_lpm_schedule(struct ata_port *ap, enum link_pm policy)
+{
+ ap->pm_policy = policy;
+ ap->link.eh_info.action |= ATA_EHI_LPM;
+ ap->link.eh_info.flags |= ATA_EHI_NO_AUTOPSY;
+ ata_port_schedule_eh(ap);
+}
+
+static void ata_lpm_enable(struct ata_host *host)
+{
+ struct ata_link *link;
+ struct ata_port *ap;
+ struct ata_device *dev;
+ int i;
+
+ for (i = 0; i < host->n_ports; i++) {
+ ap = host->ports[i];
+ ata_port_for_each_link(link, ap) {
+ ata_link_for_each_dev(dev, link)
+ ata_dev_disable_pm(dev);
+ }
+ }
+}
+
+static void ata_lpm_disable(struct ata_host *host)
+{
+ int i;
+
+ for (i = 0; i < host->n_ports; i++) {
+ struct ata_port *ap = host->ports[i];
+ ata_lpm_schedule(ap, ap->pm_policy);
+ }
+}
+
+
/**
* ata_devchk - PATA device presence detection
* @ap: ATA channel to examine
@@ -2101,6 +2272,13 @@ int ata_dev_configure(struct ata_device *dev)
if (dev->flags & ATA_DFLAG_LBA48)
dev->max_sectors = ATA_MAX_SECTORS_LBA48;
+ if (!(dev->horkage & ATA_HORKAGE_IPM)) {
+ if (ata_id_has_hipm(dev->id))
+ dev->flags |= ATA_DFLAG_HIPM;
+ if (ata_id_has_dipm(dev->id))
+ dev->flags |= ATA_DFLAG_DIPM;
+ }
+
if (dev->horkage & ATA_HORKAGE_DIAGNOSTIC) {
/* Let the user know. We don't want to disallow opens for
rescue purposes, or in case the vendor is just a blithering
@@ -2126,6 +2304,13 @@ int ata_dev_configure(struct ata_device *dev)
dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
dev->max_sectors);
+ if (ata_dev_blacklisted(dev) & ATA_HORKAGE_IPM) {
+ dev->horkage |= ATA_HORKAGE_IPM;
+
+ /* reset link pm_policy for this port to no pm */
+ ap->pm_policy = MAX_PERFORMANCE;
+ }
+
if (ap->ops->dev_config)
ap->ops->dev_config(dev);
@@ -6292,6 +6477,12 @@ int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
{
int rc;
+ /*
+ * disable link pm on all ports before requesting
+ * any pm activity
+ */
+ ata_lpm_enable(host);
+
rc = ata_host_request_pm(host, mesg, 0, ATA_EHI_QUIET, 1);
if (rc == 0)
host->dev->power.power_state = mesg;
@@ -6314,6 +6505,9 @@ void ata_host_resume(struct ata_host *host)
ata_host_request_pm(host, PMSG_ON, ATA_EH_SOFTRESET,
ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
host->dev->power.power_state = PMSG_ON;
+
+ /* reenable link pm */
+ ata_lpm_disable(host);
}
#endif
@@ -6856,6 +7050,7 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
struct ata_port *ap = host->ports[i];
ata_scsi_scan_host(ap, 1);
+ ata_lpm_schedule(ap, ap->pm_policy);
}
return 0;
@@ -7252,7 +7447,6 @@ const struct ata_port_info ata_dummy_port_info = {
* likely to change as new drivers are added and updated.
* Do not depend on ABI/API stability.
*/
-
EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
EXPORT_SYMBOL_GPL(sata_deb_timing_long);
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 93e2b54..2cae530 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -2607,6 +2607,10 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
ehc->i.flags &= ~ATA_EHI_SETMODE;
}
+ if (ehc->i.action & ATA_EHI_LPM)
+ ata_link_for_each_dev(dev, link)
+ ata_dev_enable_pm(dev, ap->pm_policy);
+
/* this link is okay now */
ehc->i.flags = 0;
continue;
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index f5d5420..2111faa 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -110,6 +110,74 @@ static struct scsi_transport_template ata_scsi_transport_template = {
};
+static const struct {
+ enum link_pm value;
+ const char *name;
+} link_pm_policy[] = {
+ { NOT_AVAILABLE, "max_performance" },
+ { MIN_POWER, "min_power" },
+ { MAX_PERFORMANCE, "max_performance" },
+ { MEDIUM_POWER, "medium_power" },
+};
+
+const char *ata_scsi_lpm_get(enum link_pm policy)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(link_pm_policy); i++)
+ if (link_pm_policy[i].value == policy)
+ return link_pm_policy[i].name;
+
+ return NULL;
+}
+
+static ssize_t ata_scsi_lpm_put(struct class_device *class_dev,
+ const char *buf, size_t count)
+{
+ struct Scsi_Host *shost = class_to_shost(class_dev);
+ struct ata_port *ap = ata_shost_to_port(shost);
+ enum link_pm policy = 0;
+ int i;
+
+ /*
+ * we are skipping array location 0 on purpose - this
+ * is because a value of NOT_AVAILABLE is displayed
+ * to the user as max_performance, but when the user
+ * writes "max_performance", they actually want the
+ * value to match MAX_PERFORMANCE.
+ */
+ for (i = 1; i < ARRAY_SIZE(link_pm_policy); i++) {
+ const int len = strlen(link_pm_policy[i].name);
+ if (strncmp(link_pm_policy[i].name, buf, len) == 0 &&
+ buf[len] == '\n') {
+ policy = link_pm_policy[i].value;
+ break;
+ }
+ }
+ if (!policy)
+ return -EINVAL;
+
+ ata_lpm_schedule(ap, policy);
+ return count;
+}
+
+static ssize_t
+ata_scsi_lpm_show(struct class_device *class_dev, char *buf)
+{
+ struct Scsi_Host *shost = class_to_shost(class_dev);
+ struct ata_port *ap = ata_shost_to_port(shost);
+ const char *policy =
+ ata_scsi_lpm_get(ap->pm_policy);
+
+ if (!policy)
+ return -EINVAL;
+
+ return snprintf(buf, 23, "%s\n", policy);
+}
+CLASS_DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
+ ata_scsi_lpm_show, ata_scsi_lpm_put);
+EXPORT_SYMBOL_GPL(class_device_attr_link_power_management_policy);
+
static void ata_scsi_invalid_field(struct scsi_cmnd *cmd,
void (*done)(struct scsi_cmnd *))
{
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 90df58a..0e6cf3a 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -101,6 +101,8 @@ extern int sata_link_init_spd(struct ata_link *link);
extern int ata_task_ioctl(struct scsi_device *scsidev, void __user *arg);
extern int ata_cmd_ioctl(struct scsi_device *scsidev, void __user *arg);
extern struct ata_port *ata_port_alloc(struct ata_host *host);
+extern void ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy);
+extern void ata_lpm_schedule(struct ata_port *ap, enum link_pm);
/* libata-acpi.c */
#ifdef CONFIG_ATA_ACPI
diff --git a/include/linux/ata.h b/include/linux/ata.h
index 8263a7b..bf84032 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -235,6 +235,7 @@ enum {
/* SETFEATURE Sector counts for SATA features */
SATA_AN = 0x05, /* Asynchronous Notification */
+ SATA_DIPM = 0x03, /* Device Initiated Power Management */
/* ATAPI stuff */
ATAPI_PKT_DMA = (1 << 0),
@@ -377,6 +378,26 @@ struct ata_taskfile {
#define ata_id_cdb_intr(id) (((id)[0] & 0x60) == 0x20)
+static inline bool ata_id_has_hipm(const u16 *id)
+{
+ u16 val = id[76];
+
+ if (val == 0 || val == 0xffff)
+ return false;
+
+ return val & (1 << 9);
+}
+
+static inline bool ata_id_has_dipm(const u16 *id)
+{
+ u16 val = id[78];
+
+ if (val == 0 || val == 0xffff)
+ return false;
+
+ return val & (1 << 3);
+}
+
static inline int ata_id_has_fua(const u16 *id)
{
if ((id[84] & 0xC000) != 0x4000)
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 6fd24e0..ededd26 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -133,6 +133,8 @@ enum {
ATA_DFLAG_ACPI_PENDING = (1 << 5), /* ACPI resume action pending */
ATA_DFLAG_ACPI_FAILED = (1 << 6), /* ACPI on devcfg has failed */
ATA_DFLAG_AN = (1 << 7), /* AN configured */
+ ATA_DFLAG_HIPM = (1 << 8), /* device supports HIPM */
+ ATA_DFLAG_DIPM = (1 << 9), /* device supports DIPM */
ATA_DFLAG_CFG_MASK = (1 << 12) - 1,
ATA_DFLAG_PIO = (1 << 12), /* device limited to PIO mode */
@@ -185,6 +187,7 @@ enum {
ATA_FLAG_ACPI_SATA = (1 << 17), /* need native SATA ACPI layout */
ATA_FLAG_AN = (1 << 18), /* controller supports AN */
ATA_FLAG_PMP = (1 << 19), /* controller supports PMP */
+ ATA_FLAG_IPM = (1 << 20), /* driver can handle IPM */
/* The following flag belongs to ap->pflags but is kept in
* ap->flags because it's referenced in many LLDs and will be
@@ -294,6 +297,7 @@ enum {
ATA_EHI_RESUME_LINK = (1 << 1), /* resume link (reset modifier) */
ATA_EHI_NO_AUTOPSY = (1 << 2), /* no autopsy */
ATA_EHI_QUIET = (1 << 3), /* be quiet */
+ ATA_EHI_LPM = (1 << 4), /* link power management action */
ATA_EHI_DID_SOFTRESET = (1 << 16), /* already soft-reset this port */
ATA_EHI_DID_HARDRESET = (1 << 17), /* already soft-reset this port */
@@ -325,6 +329,7 @@ enum {
ATA_HORKAGE_BROKEN_HPA = (1 << 4), /* Broken HPA */
ATA_HORKAGE_SKIP_PM = (1 << 5), /* Skip PM operations */
ATA_HORKAGE_HPA_SIZE = (1 << 6), /* native size off by one */
+ ATA_HORKAGE_IPM = (1 << 7), /* Link PM problems */
/* DMA mask for user DMA control: User visible values; DO NOT
renumber */
@@ -370,6 +375,18 @@ typedef int (*ata_reset_fn_t)(struct ata_link *link, unsigned int *classes,
unsigned long deadline);
typedef void (*ata_postreset_fn_t)(struct ata_link *link, unsigned int *classes);
+/*
+ * host pm policy: If you alter this, you also need to alter libata-scsi.c
+ * (for the ascii descriptions)
+ */
+enum link_pm {
+ NOT_AVAILABLE,
+ MIN_POWER,
+ MAX_PERFORMANCE,
+ MEDIUM_POWER,
+};
+extern struct class_device_attribute class_device_attr_link_power_management_policy;
+
struct ata_ioports {
void __iomem *cmd_addr;
void __iomem *data_addr;
@@ -616,6 +633,7 @@ struct ata_port {
pm_message_t pm_mesg;
int *pm_result;
+ enum link_pm pm_policy;
struct timer_list fastdrain_timer;
unsigned long fastdrain_cnt;
@@ -683,7 +701,8 @@ struct ata_port_operations {
int (*port_suspend) (struct ata_port *ap, pm_message_t mesg);
int (*port_resume) (struct ata_port *ap);
-
+ int (*enable_pm) (struct ata_port *ap, enum link_pm policy);
+ void (*disable_pm) (struct ata_port *ap);
int (*port_start) (struct ata_port *ap);
void (*port_stop) (struct ata_port *ap);