[PATCH] sata_via: use old SCR access pattern on vt6420

vt6420 has super-fragile SCR registers which can hang the whole
machine if accessed with the wrong timings.  This patch makes sata_via
use SCR registers only during probing and with the same timings as
before (pre new EH), which is proven to work.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This commit is contained in:
Tejun Heo 2006-08-23 01:00:27 +09:00 committed by Jeff Garzik
parent 9dd9c16465
commit ac2164d5e4
1 changed files with 112 additions and 5 deletions

View File

@ -74,6 +74,7 @@ enum {
static int svia_init_one (struct pci_dev *pdev, const struct pci_device_id *ent);
static u32 svia_scr_read (struct ata_port *ap, unsigned int sc_reg);
static void svia_scr_write (struct ata_port *ap, unsigned int sc_reg, u32 val);
static void vt6420_error_handler(struct ata_port *ap);
static const struct pci_device_id svia_pci_tbl[] = {
{ 0x1106, 0x3149, PCI_ANY_ID, PCI_ANY_ID, 0, 0, vt6420 },
@ -107,7 +108,38 @@ static struct scsi_host_template svia_sht = {
.bios_param = ata_std_bios_param,
};
static const struct ata_port_operations svia_sata_ops = {
static const struct ata_port_operations vt6420_sata_ops = {
.port_disable = ata_port_disable,
.tf_load = ata_tf_load,
.tf_read = ata_tf_read,
.check_status = ata_check_status,
.exec_command = ata_exec_command,
.dev_select = ata_std_dev_select,
.bmdma_setup = ata_bmdma_setup,
.bmdma_start = ata_bmdma_start,
.bmdma_stop = ata_bmdma_stop,
.bmdma_status = ata_bmdma_status,
.qc_prep = ata_qc_prep,
.qc_issue = ata_qc_issue_prot,
.data_xfer = ata_pio_data_xfer,
.freeze = ata_bmdma_freeze,
.thaw = ata_bmdma_thaw,
.error_handler = vt6420_error_handler,
.post_internal_cmd = ata_bmdma_post_internal_cmd,
.irq_handler = ata_interrupt,
.irq_clear = ata_bmdma_irq_clear,
.port_start = ata_port_start,
.port_stop = ata_port_stop,
.host_stop = ata_host_stop,
};
static const struct ata_port_operations vt6421_sata_ops = {
.port_disable = ata_port_disable,
.tf_load = ata_tf_load,
@ -141,13 +173,13 @@ static const struct ata_port_operations svia_sata_ops = {
.host_stop = ata_host_stop,
};
static struct ata_port_info svia_port_info = {
static struct ata_port_info vt6420_port_info = {
.sht = &svia_sht,
.host_flags = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY,
.pio_mask = 0x1f,
.mwdma_mask = 0x07,
.udma_mask = 0x7f,
.port_ops = &svia_sata_ops,
.port_ops = &vt6420_sata_ops,
};
MODULE_AUTHOR("Jeff Garzik");
@ -170,6 +202,81 @@ static void svia_scr_write (struct ata_port *ap, unsigned int sc_reg, u32 val)
outl(val, ap->ioaddr.scr_addr + (4 * sc_reg));
}
/**
* vt6420_prereset - prereset for vt6420
* @ap: target ATA port
*
* SCR registers on vt6420 are pieces of shit and may hang the
* whole machine completely if accessed with the wrong timing.
* To avoid such catastrophe, vt6420 doesn't provide generic SCR
* access operations, but uses SStatus and SControl only during
* boot probing in controlled way.
*
* As the old (pre EH update) probing code is proven to work, we
* strictly follow the access pattern.
*
* LOCKING:
* Kernel thread context (may sleep)
*
* RETURNS:
* 0 on success, -errno otherwise.
*/
static int vt6420_prereset(struct ata_port *ap)
{
struct ata_eh_context *ehc = &ap->eh_context;
unsigned long timeout = jiffies + (HZ * 5);
u32 sstatus, scontrol;
int online;
/* don't do any SCR stuff if we're not loading */
if (!ATA_PFLAG_LOADING)
goto skip_scr;
/* Resume phy. This is the old resume sequence from
* __sata_phy_reset().
*/
svia_scr_write(ap, SCR_CONTROL, 0x300);
svia_scr_read(ap, SCR_CONTROL); /* flush */
/* wait for phy to become ready, if necessary */
do {
msleep(200);
if ((svia_scr_read(ap, SCR_STATUS) & 0xf) != 1)
break;
} while (time_before(jiffies, timeout));
/* open code sata_print_link_status() */
sstatus = svia_scr_read(ap, SCR_STATUS);
scontrol = svia_scr_read(ap, SCR_CONTROL);
online = (sstatus & 0xf) == 0x3;
ata_port_printk(ap, KERN_INFO,
"SATA link %s 1.5 Gbps (SStatus %X SControl %X)\n",
online ? "up" : "down", sstatus, scontrol);
/* SStatus is read one more time */
svia_scr_read(ap, SCR_STATUS);
if (!online) {
/* tell EH to bail */
ehc->i.action &= ~ATA_EH_RESET_MASK;
return 0;
}
skip_scr:
/* wait for !BSY */
ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT);
return 0;
}
static void vt6420_error_handler(struct ata_port *ap)
{
return ata_bmdma_drive_eh(ap, vt6420_prereset, ata_std_softreset,
NULL, ata_std_postreset);
}
static const unsigned int svia_bar_sizes[] = {
8, 4, 8, 4, 16, 256
};
@ -210,7 +317,7 @@ static void vt6421_init_addrs(struct ata_probe_ent *probe_ent,
static struct ata_probe_ent *vt6420_init_probe_ent(struct pci_dev *pdev)
{
struct ata_probe_ent *probe_ent;
struct ata_port_info *ppi = &svia_port_info;
struct ata_port_info *ppi = &vt6420_port_info;
probe_ent = ata_pci_init_native_mode(pdev, &ppi, ATA_PORT_PRIMARY | ATA_PORT_SECONDARY);
if (!probe_ent)
@ -239,7 +346,7 @@ static struct ata_probe_ent *vt6421_init_probe_ent(struct pci_dev *pdev)
probe_ent->sht = &svia_sht;
probe_ent->host_flags = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY;
probe_ent->port_ops = &svia_sata_ops;
probe_ent->port_ops = &vt6421_sata_ops;
probe_ent->n_ports = N_PORTS;
probe_ent->irq = pdev->irq;
probe_ent->irq_flags = IRQF_SHARED;