[RFC PATCH] sata_via: Implement hotplug for VT6421

From: Ondrej Zary
Date: Thu Feb 25 2016 - 11:22:43 EST


Enable IRQ on hotplug and add an interrupt handler to handle it.

This allows hotplug to work:
ata5: exception Emask 0x10 SAct 0x0 SErr 0x70000 action 0xe frozen
ata5: SError: { PHYRdyChg PHYInt CommWake }
ata5: hard resetting link
ata5: SATA link up 1.5 Gbps (SStatus 113 SControl 310)
ata5.00: LPM support broken, forcing max_power
ata5.00: ATA-7: WDC WD800JD-75MSA3, 10.01E04, max UDMA/133
ata5.00: 156250000 sectors, multi 0: LBA48 NCQ (depth 0/32)
ata5.00: LPM support broken, forcing max_power
ata5.00: configured for UDMA/133
ata5: EH complete
scsi 4:0:0:0: Direct-Access ATA WDC WD800JD-75MS 1E04 PQ: 0 ANSI: 5
sd 4:0:0:0: [sdb] 156250000 512-byte logical blocks: (80.0 GB/74.5 GiB)
sd 4:0:0:0: [sdb] Write Protect is off
sd 4:0:0:0: [sdb] Mode Sense: 00 3a 00 00
sd 4:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
sd 4:0:0:0: Attached scsi generic sg1 type 0
sd 4:0:0:0: [sdb] Attached SCSI disk

And also hot unplug:
ata5: exception Emask 0x10 SAct 0x0 SErr 0x1b0000 action 0xe frozen
ata5: SError: { PHYRdyChg PHYInt 10B8B Dispar }
ata5: hard resetting link
ata5: SATA link down (SStatus 0 SControl 310)
ata5: hard resetting link
ata5: SATA link down (SStatus 0 SControl 310)
ata5: hard resetting link
ata5: SATA link down (SStatus 0 SControl 310)
ata5.00: disabled
ata5: EH complete
ata5.00: detaching (SCSI 4:0:0:0)
sd 4:0:0:0: [sdb] Synchronizing SCSI cache
sd 4:0:0:0: [sdb] Synchronize Cache(10) failed: Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK
sd 4:0:0:0: [sdb] Stopping disk
sd 4:0:0:0: [sdb] Start/Stop Unit failed: Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK

Signed-off-by: Ondrej Zary <linux@xxxxxxxxxxxxxxxxxxxx>
---
drivers/ata/sata_via.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 50 insertions(+), 2 deletions(-)

diff --git a/drivers/ata/sata_via.c b/drivers/ata/sata_via.c
index 9804054..0636d84 100644
--- a/drivers/ata/sata_via.c
+++ b/drivers/ata/sata_via.c
@@ -61,6 +61,7 @@ enum {
SATA_CHAN_ENAB = 0x40, /* SATA channel enable */
SATA_INT_GATE = 0x41, /* SATA interrupt gating */
SATA_NATIVE_MODE = 0x42, /* Native mode enable */
+ SVIA_MISC_3 = 0x46, /* Miscellaneous Control III */
PATA_UDMA_TIMING = 0xB3, /* PATA timing for DMA/ cable detect */
PATA_PIO_TIMING = 0xAB, /* PATA timing register */

@@ -71,6 +72,8 @@ enum {
NATIVE_MODE_ALL = (1 << 7) | (1 << 6) | (1 << 5) | (1 << 4),

SATA_EXT_PHY = (1 << 6), /* 0==use PATA, 1==ext phy */
+
+ SATA_HOTPLUG = (1 << 5), /* enable IRQ on hotplug */
};

struct svia_priv {
@@ -553,6 +556,37 @@ static void svia_wd_fix(struct pci_dev *pdev)
pci_write_config_byte(pdev, 0x52, tmp8 | BIT(2));
}

+static irqreturn_t vt6421_interrupt(int irq, void *dev_instance)
+{
+ struct ata_host *host = dev_instance;
+ irqreturn_t rc = ata_bmdma_interrupt(irq, dev_instance);
+
+ /* if the IRQ was not handled, it might be a hotplug IRQ */
+ if (rc != IRQ_HANDLED) {
+ u32 serror;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+ /* check for hotplug on port 0 */
+ svia_scr_read(&host->ports[0]->link, SCR_ERROR, &serror);
+ if (serror & SERR_PHYRDY_CHG) {
+ ata_ehi_hotplugged(&host->ports[0]->link.eh_info);
+ ata_port_freeze(host->ports[0]);
+ rc = IRQ_HANDLED;
+ }
+ /* check for hotplug on port 1 */
+ svia_scr_read(&host->ports[1]->link, SCR_ERROR, &serror);
+ if (serror & SERR_PHYRDY_CHG) {
+ ata_ehi_hotplugged(&host->ports[1]->link.eh_info);
+ ata_port_freeze(host->ports[1]);
+ rc = IRQ_HANDLED;
+ }
+ spin_unlock_irqrestore(&host->lock, flags);
+ }
+
+ return rc;
+}
+
static void vt6421_error_handler(struct ata_port *ap)
{
struct svia_priv *hpriv = ap->host->private_data;
@@ -610,6 +644,16 @@ static void svia_configure(struct pci_dev *pdev, int board_id,
pci_write_config_byte(pdev, SATA_NATIVE_MODE, tmp8);
}

+ /* enable IRQ on hotplug */
+ pci_read_config_byte(pdev, SVIA_MISC_3, &tmp8);
+ if ((tmp8 & SATA_HOTPLUG) != SATA_HOTPLUG) {
+ dev_dbg(&pdev->dev,
+ "enabling SATA hotplug (0x%x)\n",
+ (int) tmp8);
+ tmp8 |= SATA_HOTPLUG;
+ pci_write_config_byte(pdev, SVIA_MISC_3, tmp8);
+ }
+
/*
* vt6420/1 has problems talking to some drives. The following
* is the fix from Joseph Chan <JosephChan@xxxxxxxxxx>.
@@ -698,8 +742,12 @@ static int svia_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
svia_configure(pdev, board_id, hpriv);

pci_set_master(pdev);
- return ata_host_activate(host, pdev->irq, ata_bmdma_interrupt,
- IRQF_SHARED, &svia_sht);
+ if (board_id == vt6421)
+ return ata_host_activate(host, pdev->irq, vt6421_interrupt,
+ IRQF_SHARED, &svia_sht);
+ else
+ return ata_host_activate(host, pdev->irq, ata_bmdma_interrupt,
+ IRQF_SHARED, &svia_sht);
}

#ifdef CONFIG_PM_SLEEP
--
Ondrej Zary