_GTM fetches currently configured transfer mode while _STM configures
controller according to _GTM parameter and prepares transfer mode
configuration TFs for _GTF. In many cases _GTM and _STM
implementations are quite brittle and can't cope with configuration
changed by libata.
libata does not depend on ATA ACPI to configure devices. The only
reason libata performs _GTM and _STM are to make _GTF evaluation
succeed and libata also doesn't care about how _GTF TFs configure
transfer mode. It overrides that configuration anyway, so from
libata's POV, it doesn't matter what value is feeded to _STM as long
as evaluation succeeds for _STM and following _GTF.
This patch adds dev->__acpi_init_gtm and store initial _GTM values on
host initialization before modified by reset and mode configuration.
If the field is valid, ata_acpi_init_gtm() returns pointer to the
saved _GTM structure; otherwise, NULL.
This saved value is used for _STM during resume and peek at
BIOS/firmware programmed initial timing for later use. The accessor
is there to make building w/o ACPI easy as dev->__acpi_init doesn't
exist if ACPI is not enabled.
On driver detach, the initial BIOS configuration is restored by
executing _STM with the initial _GTM values such that the next driver
can also use the initial BIOS configured values.
Signed-off-by: Tejun Heo <htejun@xxxxxxxxx>
---
drivers/ata/libata-acpi.c | 62 +++++++++++++++++++-------------------------
include/linux/libata.h | 14 ++++++++-
2 files changed, 39 insertions(+), 37 deletions(-)
diff --git a/drivers/ata/libata-acpi.c b/drivers/ata/libata-acpi.c
index 9e5fc5d..b3aeca3 100644
--- a/drivers/ata/libata-acpi.c
+++ b/drivers/ata/libata-acpi.c
@@ -94,6 +94,9 @@ static void ata_acpi_associate_ide_port(struct ata_port *ap)
dev->acpi_handle = acpi_get_child(ap->acpi_handle, i);
}
+
+ if (ata_acpi_gtm(ap, &ap->__acpi_init_gtm) == 0)
+ ap->pflags |= ATA_PFLAG_INIT_GTM_VALID;
}
static void ata_acpi_handle_hotplug(struct ata_port *ap, struct kobject *kobj,
@@ -199,7 +202,18 @@ void ata_acpi_associate(struct ata_host *host)
*/
void ata_acpi_dissociate(struct ata_host *host)
{
- /* nada */
+ int i;
+
+ /* Restore initial _GTM values so that driver which attaches
+ * afterward can use them too.
+ */
+ for (i = 0; i < host->n_ports; i++) {
+ struct ata_port *ap = host->ports[i];
+ const struct ata_acpi_gtm *gtm = ata_acpi_init_gtm(ap);
+
+ if (ap->acpi_handle && gtm)
+ ata_acpi_stm(ap, gtm);
+ }
}
/**
@@ -409,22 +423,21 @@ static int ata_dev_get_GTF(struct ata_device *dev, struct ata_acpi_gtf **gtf,
int ata_acpi_cbl_80wire(struct ata_port *ap)
{
- struct ata_acpi_gtm gtm;
+ const struct ata_acpi_gtm *gtm = ata_acpi_init_gtm(ap);
int valid = 0;
- /* No _GTM data, no information */
- if (ata_acpi_gtm(ap, >m) < 0)
+ if (!gtm)
return 0;
/* Split timing, DMA enabled */
- if ((gtm.flags & 0x11) == 0x11 && gtm.drive[0].dma < 55)
+ if ((gtm->flags & 0x11) == 0x11 && gtm->drive[0].dma < 55)
valid |= 1;
- if ((gtm.flags & 0x14) == 0x14 && gtm.drive[1].dma < 55)
+ if ((gtm->flags & 0x14) == 0x14 && gtm->drive[1].dma < 55)
valid |= 2;
/* Shared timing, DMA enabled */
- if ((gtm.flags & 0x11) == 0x01 && gtm.drive[0].dma < 55)
+ if ((gtm->flags & 0x11) == 0x01 && gtm->drive[0].dma < 55)
valid |= 1;
- if ((gtm.flags & 0x14) == 0x04 && gtm.drive[0].dma < 55)
+ if ((gtm->flags & 0x14) == 0x04 && gtm->drive[0].dma < 55)
valid |= 2;
/* Drive check */
@@ -612,27 +625,8 @@ static int ata_acpi_push_id(struct ata_device *dev)
*/
int ata_acpi_on_suspend(struct ata_port *ap)
{
- unsigned long flags;
- int rc;
-
- /* proceed iff per-port acpi_handle is valid */
- if (!ap->acpi_handle)
- return 0;
- BUG_ON(ap->flags & ATA_FLAG_ACPI_SATA);
-
- /* store timing parameters */
- rc = ata_acpi_gtm(ap, &ap->acpi_gtm);
-
- spin_lock_irqsave(ap->lock, flags);
- if (rc == 0)
- ap->pflags |= ATA_PFLAG_GTM_VALID;
- else
- ap->pflags &= ~ATA_PFLAG_GTM_VALID;
- spin_unlock_irqrestore(ap->lock, flags);
-
- if (rc == -ENOENT)
- rc = 0;
- return rc;
+ /* nada */
+ return 0;
}
/**
@@ -647,14 +641,12 @@ int ata_acpi_on_suspend(struct ata_port *ap)
*/
void ata_acpi_on_resume(struct ata_port *ap)
{
+ const struct ata_acpi_gtm *gtm = ata_acpi_init_gtm(ap);
struct ata_device *dev;
- if (ap->acpi_handle && (ap->pflags & ATA_PFLAG_GTM_VALID)) {
- BUG_ON(ap->flags & ATA_FLAG_ACPI_SATA);
-
- /* restore timing parameters */
- ata_acpi_stm(ap, &ap->acpi_gtm);
- }
+ /* restore timing parameters */
+ if (ap->acpi_handle && gtm)
+ ata_acpi_stm(ap, gtm);
/* schedule _GTF */
ata_link_for_each_dev(dev, &ap->link)
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 3784af3..ba84d8a 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -211,7 +211,7 @@ enum {
ATA_PFLAG_SUSPENDED = (1 << 17), /* port is suspended (power) */
ATA_PFLAG_PM_PENDING = (1 << 18), /* PM operation pending */
- ATA_PFLAG_GTM_VALID = (1 << 19), /* acpi_gtm data valid */
+ ATA_PFLAG_INIT_GTM_VALID = (1 << 19), /* initial gtm data valid */
/* struct ata_queued_cmd flags */
ATA_QCFLAG_ACTIVE = (1 << 0), /* cmd not yet ack'd to scsi lyer */
@@ -653,7 +653,7 @@ struct ata_port {
#ifdef CONFIG_ATA_ACPI
acpi_handle acpi_handle;
- struct ata_acpi_gtm acpi_gtm;
+ struct ata_acpi_gtm __acpi_init_gtm; /* use ata_acpi_init_gtm() */
#endif
u8 sector_buf[ATA_SECT_SIZE]; /* owned by EH */
};
@@ -939,10 +939,20 @@ enum {
/* libata-acpi.c */
#ifdef CONFIG_ATA_ACPI
+static inline const struct ata_acpi_gtm *ata_acpi_init_gtm(struct ata_port *ap)
+{
+ if (ap->pflags & ATA_PFLAG_INIT_GTM_VALID)
+ return &ap->__acpi_init_gtm;
+ return NULL;
+}
extern int ata_acpi_cbl_80wire(struct ata_port *ap);
int ata_acpi_stm(struct ata_port *ap, const struct ata_acpi_gtm *stm);
int ata_acpi_gtm(struct ata_port *ap, struct ata_acpi_gtm *stm);
#else
+static inline const struct ata_acpi_gtm *ata_acpi_init_gtm(struct ata_port *ap)
+{
+ return NULL;
+}
static inline int ata_acpi_cbl_80wire(struct ata_port *ap) { return 0; }
#endif
--
1.5.2.4
-
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