libata: use ata_exec_internal() for PMP register access
PMP registers used to be accessed with dedicated accessors ->pmp_read
and ->pmp_write. During reset, those callbacks are called with the
port frozen so they should be able to run without depending on
interrupt delivery. To achieve this, they were implemented polling.
However, as resetting the host port makes the PMP to isolate fan-out
ports until SError.X is cleared, resetting fan-out ports while port is
frozen doesn't buy much additional safety.
This patch updates libata PMP support such that PMP registers are
accessed using regular ata_exec_internal() mechanism and kills
->pmp_read/write() callbacks. The following changes are made.
* PMP access helpers - sata_pmp_read_init_tf(), sata_pmp_read_val(),
sata_pmp_write_init_tf() are folded into sata_pmp_read/write() which
are now standalone PMP register access functions.
* sata_pmp_read/write() returns err_mask instead of rc. This is
consistent with other functions which issue internal commands and
allows more detailed error reporting.
* ahci interrupt handler is modified to ignore BAD_PMP and
spurious/illegal completion IRQs while reset is in progress. These
conditions are expected during reset.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index abfb72a..10bc3f6 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -239,8 +239,6 @@
static void ahci_thaw(struct ata_port *ap);
static void ahci_pmp_attach(struct ata_port *ap);
static void ahci_pmp_detach(struct ata_port *ap);
-static int ahci_pmp_read(struct ata_device *dev, int pmp, int reg, u32 *r_val);
-static int ahci_pmp_write(struct ata_device *dev, int pmp, int reg, u32 val);
static void ahci_error_handler(struct ata_port *ap);
static void ahci_vt8251_error_handler(struct ata_port *ap);
static void ahci_post_internal_cmd(struct ata_queued_cmd *qc);
@@ -297,8 +295,6 @@
.pmp_attach = ahci_pmp_attach,
.pmp_detach = ahci_pmp_detach,
- .pmp_read = ahci_pmp_read,
- .pmp_write = ahci_pmp_write,
#ifdef CONFIG_PM
.port_suspend = ahci_port_suspend,
@@ -333,8 +329,6 @@
.pmp_attach = ahci_pmp_attach,
.pmp_detach = ahci_pmp_detach,
- .pmp_read = ahci_pmp_read,
- .pmp_write = ahci_pmp_write,
#ifdef CONFIG_PM
.port_suspend = ahci_port_suspend,
@@ -1421,12 +1415,17 @@
struct ata_eh_info *ehi = &ap->link.eh_info;
struct ahci_port_priv *pp = ap->private_data;
struct ahci_host_priv *hpriv = ap->host->private_data;
+ int resetting = !!(ap->pflags & ATA_PFLAG_RESETTING);
u32 status, qc_active;
int rc, known_irq = 0;
status = readl(port_mmio + PORT_IRQ_STAT);
writel(status, port_mmio + PORT_IRQ_STAT);
+ /* ignore BAD_PMP while resetting */
+ if (unlikely(resetting))
+ status &= ~PORT_IRQ_BAD_PMP;
+
if (unlikely(status & PORT_IRQ_ERROR)) {
ahci_error_intr(ap, status);
return;
@@ -1464,6 +1463,13 @@
qc_active = readl(port_mmio + PORT_CMD_ISSUE);
rc = ata_qc_complete_multiple(ap, qc_active, NULL);
+
+ /* If resetting, spurious or invalid completions are expected,
+ * return unconditionally.
+ */
+ if (resetting)
+ return;
+
if (rc > 0)
return;
if (rc < 0) {
@@ -1701,36 +1707,6 @@
writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
}
-static int ahci_pmp_read(struct ata_device *dev, int pmp, int reg, u32 *r_val)
-{
- struct ata_port *ap = dev->link->ap;
- struct ata_taskfile tf;
- int rc;
-
- ahci_kick_engine(ap, 0);
-
- sata_pmp_read_init_tf(&tf, dev, pmp, reg);
- rc = ahci_exec_polled_cmd(ap, SATA_PMP_CTRL_PORT, &tf, 1, 0,
- SATA_PMP_SCR_TIMEOUT);
- if (rc == 0) {
- ahci_tf_read(ap, &tf);
- *r_val = sata_pmp_read_val(&tf);
- }
- return rc;
-}
-
-static int ahci_pmp_write(struct ata_device *dev, int pmp, int reg, u32 val)
-{
- struct ata_port *ap = dev->link->ap;
- struct ata_taskfile tf;
-
- ahci_kick_engine(ap, 0);
-
- sata_pmp_write_init_tf(&tf, dev, pmp, reg, val);
- return ahci_exec_polled_cmd(ap, SATA_PMP_CTRL_PORT, &tf, 1, 0,
- SATA_PMP_SCR_TIMEOUT);
-}
-
static int ahci_port_resume(struct ata_port *ap)
{
ahci_power_up(ap);