Commit 4ae41ff8 authored by Kou Ishizaki's avatar Kou Ishizaki Committed by Bartlomiej Zolnierkiewicz

scc_pata.c: Workaround for errata A308 (take 2)

Workaround for errata A308: turn down the UDMA mode and retry
the DMA command when the data lost condition is detected.

take2:
udma_filter() hook is used to limit ATAPI UDMA mode.
Signed-off-by: default avatarKou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: default avatarAkira Iguchi <akira2.iguchi@toshiba.co.jp>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: default avatarBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
parent f644d47a
......@@ -401,6 +401,33 @@ static int scc_ide_dma_end(ide_drive_t * drive)
ide_hwif_t *hwif = HWIF(drive);
unsigned long intsts_port = hwif->dma_base + 0x014;
u32 reg;
int dma_stat, data_loss = 0;
static int retry = 0;
/* errata A308 workaround: Step5 (check data loss) */
/* We don't check non ide_disk because it is limited to UDMA4 */
if (!(in_be32((void __iomem *)IDE_ALTSTATUS_REG) & ERR_STAT) &&
drive->media == ide_disk && drive->current_speed > XFER_UDMA_4) {
reg = in_be32((void __iomem *)intsts_port);
if (!(reg & INTSTS_ACTEINT)) {
printk(KERN_WARNING "%s: operation failed (transfer data loss)\n",
drive->name);
data_loss = 1;
if (retry++) {
struct request *rq = HWGROUP(drive)->rq;
int unit;
/* ERROR_RESET and drive->crc_count are needed
* to reduce DMA transfer mode in retry process.
*/
if (rq)
rq->errors |= ERROR_RESET;
for (unit = 0; unit < MAX_DRIVES; unit++) {
ide_drive_t *drive = &hwif->drives[unit];
drive->crc_count++;
}
}
}
}
while (1) {
reg = in_be32((void __iomem *)intsts_port);
......@@ -469,27 +496,25 @@ static int scc_ide_dma_end(ide_drive_t * drive)
break;
}
return __ide_dma_end(drive);
dma_stat = __ide_dma_end(drive);
if (data_loss)
dma_stat |= 2; /* emulate DMA error (to retry command) */
return dma_stat;
}
/* returns 1 if dma irq issued, 0 otherwise */
static int scc_dma_test_irq(ide_drive_t *drive)
{
ide_hwif_t *hwif = HWIF(drive);
u8 dma_stat = hwif->INB(hwif->dma_status);
u32 int_stat = in_be32((void __iomem *)hwif->dma_base + 0x014);
/* return 1 if INTR asserted */
if ((dma_stat & 4) == 4)
/* SCC errata A252,A308 workaround: Step4 */
if ((in_be32((void __iomem *)IDE_ALTSTATUS_REG) & ERR_STAT) &&
(int_stat & INTSTS_INTRQ))
return 1;
/* Workaround for PTERADD: emulate DMA_INTR when
* - IDE_STATUS[ERR] = 1
* - INT_STATUS[INTRQ] = 1
* - DMA_STATUS[IORACTA] = 1
*/
if (in_be32((void __iomem *)IDE_ALTSTATUS_REG) & ERR_STAT &&
in_be32((void __iomem *)(hwif->dma_base + 0x014)) & INTSTS_INTRQ &&
dma_stat & 1)
/* SCC errata A308 workaround: Step5 (polling IOIRQS) */
if (int_stat & INTSTS_IOIRQS)
return 1;
if (!drive->waiting_for_dma)
......@@ -498,6 +523,21 @@ static int scc_dma_test_irq(ide_drive_t *drive)
return 0;
}
static u8 scc_udma_filter(ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
u8 mask = hwif->ultra_mask;
/* errata A308 workaround: limit non ide_disk drive to UDMA4 */
if ((drive->media != ide_disk) && (mask & 0xE0)) {
printk(KERN_INFO "%s: limit %s to UDMA4\n",
SCC_PATA_NAME, drive->name);
mask = 0x1F;
}
return mask;
}
/**
* setup_mmio_scc - map CTRL/BMID region
* @dev: PCI device we are configuring
......@@ -702,6 +742,7 @@ static void __devinit init_hwif_scc(ide_hwif_t *hwif)
hwif->tuneproc = scc_tuneproc;
hwif->ide_dma_check = scc_config_drive_for_dma;
hwif->ide_dma_test_irq = scc_dma_test_irq;
hwif->udma_filter = scc_udma_filter;
hwif->drives[0].autotune = IDE_TUNE_AUTO;
hwif->drives[1].autotune = IDE_TUNE_AUTO;
......
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