path: root/include/linux/libata.h
diff options
authorTejun Heo <htejun@gmail.com>2007-12-15 15:05:02 +0900
committerJeff Garzik <jeff@garzik.org>2007-12-17 20:33:14 -0500
commitc05e6ff035c1b25d17364a685432b33937d3dc23 (patch)
tree08c9171d024b6659b29a4f9f7d95318430b75b6a /include/linux/libata.h
parent562f0c2d771ee7be6b37fe015f94a929f8056120 (diff)
libata-acpi: implement and use ata_acpi_init_gtm()
_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@gmail.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Diffstat (limited to 'include/linux/libata.h')
1 files changed, 12 insertions, 2 deletions
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 3784af395576..ba84d8a37545 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 {
acpi_handle acpi_handle;
- struct ata_acpi_gtm acpi_gtm;
+ struct ata_acpi_gtm __acpi_init_gtm; /* use ata_acpi_init_gtm() */
u8 sector_buf[ATA_SECT_SIZE]; /* owned by EH */
@@ -939,10 +939,20 @@ enum {
/* libata-acpi.c */
+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);
+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; }

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