libata-acpi: implement dev->gtf_cache and evaluate _GTF right after _STM during resume
On certain implementations, _GTF evaluation depends on preceding _STM
and both can be pretty picky about the configuration. Using _GTM
result cached during controller initialization satisfies the most
neurotic _STM implementation. However, libata evaluates _GTF after
reset during device configuration and the hardware state can be
different from what _GTF expects and can cause evaluation failure.
This patch adds dev->gtf_cache and updates ata_dev_get_GTF() such that
it uses the cached value if available. Cache is cleared with a call
to ata_acpi_clear_gtf().
Because for SATA ACPI nodes _GTF must be evaluated after _SDD which
can't be done till IDENTIFY is complete, _GTF caching from
ata_acpi_on_resume() is used only for IDE ACPI nodes.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/libata-acpi.c b/drivers/ata/libata-acpi.c
index b3aeca3..e0dd132 100644
--- a/drivers/ata/libata-acpi.c
+++ b/drivers/ata/libata-acpi.c
@@ -41,6 +41,12 @@
return (dev->bus == &pci_bus_type);
}
+static void ata_acpi_clear_gtf(struct ata_device *dev)
+{
+ kfree(dev->gtf_cache);
+ dev->gtf_cache = NULL;
+}
+
/**
* ata_acpi_associate_sata_port - associate SATA port with ACPI objects
* @ap: target SATA port
@@ -327,7 +333,6 @@
* ata_dev_get_GTF - get the drive bootup default taskfile settings
* @dev: target ATA device
* @gtf: output parameter for buffer containing _GTF taskfile arrays
- * @ptr_to_free: pointer which should be freed
*
* This applies to both PATA and SATA drives.
*
@@ -344,8 +349,7 @@
* Number of taskfiles on success, 0 if _GTF doesn't exist or doesn't
* contain valid data.
*/
-static int ata_dev_get_GTF(struct ata_device *dev, struct ata_acpi_gtf **gtf,
- void **ptr_to_free)
+static int ata_dev_get_GTF(struct ata_device *dev, struct ata_acpi_gtf **gtf)
{
struct ata_port *ap = dev->link->ap;
acpi_status status;
@@ -353,6 +357,12 @@
union acpi_object *out_obj;
int rc = 0;
+ /* if _GTF is cached, use the cached value */
+ if (dev->gtf_cache) {
+ out_obj = dev->gtf_cache;
+ goto done;
+ }
+
/* set up output buffer */
output.length = ACPI_ALLOCATE_BUFFER;
output.pointer = NULL; /* ACPI-CA sets this; save/free it later */
@@ -363,6 +373,7 @@
/* _GTF has no input parameters */
status = acpi_evaluate_object(dev->acpi_handle, "_GTF", NULL, &output);
+ out_obj = dev->gtf_cache = output.pointer;
if (ACPI_FAILURE(status)) {
if (status != AE_NOT_FOUND) {
@@ -383,7 +394,6 @@
goto out_free;
}
- out_obj = output.pointer;
if (out_obj->type != ACPI_TYPE_BUFFER) {
ata_dev_printk(dev, KERN_WARNING,
"_GTF unexpected object type 0x%x\n",
@@ -398,18 +408,19 @@
goto out_free;
}
- *ptr_to_free = out_obj;
- *gtf = (void *)out_obj->buffer.pointer;
+ done:
rc = out_obj->buffer.length / REGS_PER_GTF;
-
- if (ata_msg_probe(ap))
- ata_dev_printk(dev, KERN_DEBUG, "%s: returning "
- "gtf=%p, gtf_count=%d, ptr_to_free=%p\n",
- __FUNCTION__, *gtf, rc, *ptr_to_free);
+ if (gtf) {
+ *gtf = (void *)out_obj->buffer.pointer;
+ if (ata_msg_probe(ap))
+ ata_dev_printk(dev, KERN_DEBUG,
+ "%s: returning gtf=%p, gtf_count=%d\n",
+ __FUNCTION__, *gtf, rc);
+ }
return rc;
out_free:
- kfree(output.pointer);
+ ata_acpi_clear_gtf(dev);
return rc;
}
@@ -533,11 +544,10 @@
static int ata_acpi_exec_tfs(struct ata_device *dev)
{
struct ata_acpi_gtf *gtf = NULL;
- void *ptr_to_free = NULL;
int gtf_count, i, rc;
/* get taskfiles */
- gtf_count = ata_dev_get_GTF(dev, >f, &ptr_to_free);
+ gtf_count = ata_dev_get_GTF(dev, >f);
/* execute them */
for (i = 0, rc = 0; i < gtf_count; i++) {
@@ -551,7 +561,7 @@
rc = tmp;
}
- kfree(ptr_to_free);
+ ata_acpi_clear_gtf(dev);
if (rc == 0)
return gtf_count;
@@ -644,13 +654,31 @@
const struct ata_acpi_gtm *gtm = ata_acpi_init_gtm(ap);
struct ata_device *dev;
- /* restore timing parameters */
- if (ap->acpi_handle && gtm)
+ if (ap->acpi_handle && gtm) {
+ /* _GTM valid */
+
+ /* restore timing parameters */
ata_acpi_stm(ap, gtm);
- /* schedule _GTF */
- ata_link_for_each_dev(dev, &ap->link)
- dev->flags |= ATA_DFLAG_ACPI_PENDING;
+ /* _GTF should immediately follow _STM so that it can
+ * use values set by _STM. Cache _GTF result and
+ * schedule _GTF.
+ */
+ ata_link_for_each_dev(dev, &ap->link) {
+ ata_acpi_clear_gtf(dev);
+ if (ata_dev_get_GTF(dev, NULL) >= 0)
+ dev->flags |= ATA_DFLAG_ACPI_PENDING;
+ }
+ } else {
+ /* SATA _GTF needs to be evaulated after _SDD and
+ * there's no reason to evaluate IDE _GTF early
+ * without _STM. Clear cache and schedule _GTF.
+ */
+ ata_link_for_each_dev(dev, &ap->link) {
+ ata_acpi_clear_gtf(dev);
+ dev->flags |= ATA_DFLAG_ACPI_PENDING;
+ }
+ }
}
/**
@@ -735,4 +763,5 @@
*/
void ata_acpi_on_disable(struct ata_device *dev)
{
+ ata_acpi_clear_gtf(dev);
}