diff options
| -rw-r--r-- | drivers/ata/sata_mv.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c index 10ef9683f048..692996216b1a 100644 --- a/drivers/ata/sata_mv.c +++ b/drivers/ata/sata_mv.c @@ -888,6 +888,25 @@ static void mv_start_dma(struct ata_port *ap, void __iomem *port_mmio, } } +static void mv_wait_for_edma_empty_idle(struct ata_port *ap) +{ + void __iomem *port_mmio = mv_ap_base(ap); + const u32 empty_idle = (EDMA_STATUS_CACHE_EMPTY | EDMA_STATUS_IDLE); + const int per_loop = 5, timeout = (15 * 1000 / per_loop); + int i; + + /* + * Wait for the EDMA engine to finish transactions in progress. + */ + for (i = 0; i < timeout; ++i) { + u32 edma_stat = readl(port_mmio + EDMA_STATUS_OFS); + if ((edma_stat & empty_idle) == empty_idle) + break; + udelay(per_loop); + } + /* ata_port_printk(ap, KERN_INFO, "%s: %u+ usecs\n", __func__, i); */ +} + /** * mv_stop_edma_engine - Disable eDMA engine * @port_mmio: io base address @@ -920,6 +939,7 @@ static int mv_stop_edma(struct ata_port *ap) if (!(pp->pp_flags & MV_PP_FLAG_EDMA_EN)) return 0; pp->pp_flags &= ~MV_PP_FLAG_EDMA_EN; + mv_wait_for_edma_empty_idle(ap); if (mv_stop_edma_engine(port_mmio)) { ata_port_printk(ap, KERN_ERR, "Unable to stop eDMA\n"); return -EIO; |