diff options
Diffstat (limited to 'drivers/ata')
| -rw-r--r-- | drivers/ata/sata_mv.c | 91 |
1 files changed, 70 insertions, 21 deletions
diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c index 1f14b1b52340..146b8e67c44f 100644 --- a/drivers/ata/sata_mv.c +++ b/drivers/ata/sata_mv.c @@ -438,6 +438,17 @@ struct mv_sg { __le32 reserved; }; +/* + * We keep a local cache of a few frequently accessed port + * registers here, to avoid having to read them (very slow) + * when switching between EDMA and non-EDMA modes. + */ +struct mv_cached_regs { + u32 fiscfg; + u32 ltmode; + u32 haltcond; +}; + struct mv_port_priv { struct mv_crqb *crqb; dma_addr_t crqb_dma; @@ -450,6 +461,7 @@ struct mv_port_priv { unsigned int resp_idx; u32 pp_flags; + struct mv_cached_regs cached; unsigned int delayed_eh_pmp_map; }; @@ -812,6 +824,43 @@ static inline int mv_get_hc_count(unsigned long port_flags) return ((port_flags & MV_FLAG_DUAL_HC) ? 2 : 1); } +/** + * mv_save_cached_regs - (re-)initialize cached port registers + * @ap: the port whose registers we are caching + * + * Initialize the local cache of port registers, + * so that reading them over and over again can + * be avoided on the hotter paths of this driver. + * This saves a few microseconds each time we switch + * to/from EDMA mode to perform (eg.) a drive cache flush. + */ +static void mv_save_cached_regs(struct ata_port *ap) +{ + void __iomem *port_mmio = mv_ap_base(ap); + struct mv_port_priv *pp = ap->private_data; + + pp->cached.fiscfg = readl(port_mmio + FISCFG_OFS); + pp->cached.ltmode = readl(port_mmio + LTMODE_OFS); + pp->cached.haltcond = readl(port_mmio + EDMA_HALTCOND_OFS); +} + +/** + * mv_write_cached_reg - write to a cached port register + * @addr: hardware address of the register + * @old: pointer to cached value of the register + * @new: new value for the register + * + * Write a new value to a cached register, + * but only if the value is different from before. + */ +static inline void mv_write_cached_reg(void __iomem *addr, u32 *old, u32 new) +{ + if (new != *old) { + *old = new; + writel(new, addr); + } +} + static void mv_set_edma_ptrs(void __iomem *port_mmio, struct mv_host_priv *hpriv, struct mv_port_priv *pp) @@ -1159,35 +1208,33 @@ static int mv_qc_defer(struct ata_queued_cmd *qc) return ATA_DEFER_PORT; } -static void mv_config_fbs(void __iomem *port_mmio, int want_ncq, int want_fbs) +static void mv_config_fbs(struct ata_port *ap, int want_ncq, int want_fbs) { - u32 new_fiscfg, old_fiscfg; - u32 new_ltmode, old_ltmode; - u32 new_haltcond, old_haltcond; + struct mv_port_priv *pp = ap->private_data; + void __iomem *port_mmio; - old_fiscfg = readl(port_mmio + FISCFG_OFS); - old_ltmode = readl(port_mmio + LTMODE_OFS); - old_haltcond = readl(port_mmio + EDMA_HALTCOND_OFS); + u32 fiscfg, *old_fiscfg = &pp->cached.fiscfg; + u32 ltmode, *old_ltmode = &pp->cached.ltmode; + u32 haltcond, *old_haltcond = &pp->cached.haltcond; - new_fiscfg = old_fiscfg & ~(FISCFG_SINGLE_SYNC | FISCFG_WAIT_DEV_ERR); - new_ltmode = old_ltmode & ~LTMODE_BIT8; - new_haltcond = old_haltcond | EDMA_ERR_DEV; + ltmode = *old_ltmode & ~LTMODE_BIT8; + haltcond = *old_haltcond | EDMA_ERR_DEV; if (want_fbs) { - new_fiscfg = old_fiscfg | FISCFG_SINGLE_SYNC; - new_ltmode = old_ltmode | LTMODE_BIT8; + fiscfg = *old_fiscfg | FISCFG_SINGLE_SYNC; + ltmode = *old_ltmode | LTMODE_BIT8; if (want_ncq) - new_haltcond &= ~EDMA_ERR_DEV; + haltcond &= ~EDMA_ERR_DEV; else - new_fiscfg |= FISCFG_WAIT_DEV_ERR; + fiscfg |= FISCFG_WAIT_DEV_ERR; + } else { + fiscfg = *old_fiscfg & ~(FISCFG_SINGLE_SYNC | FISCFG_WAIT_DEV_ERR); } - if (new_fiscfg != old_fiscfg) - writelfl(new_fiscfg, port_mmio + FISCFG_OFS); - if (new_ltmode != old_ltmode) - writelfl(new_ltmode, port_mmio + LTMODE_OFS); - if (new_haltcond != old_haltcond) - writelfl(new_haltcond, port_mmio + EDMA_HALTCOND_OFS); + port_mmio = mv_ap_base(ap); + mv_write_cached_reg(port_mmio + FISCFG_OFS, old_fiscfg, fiscfg); + mv_write_cached_reg(port_mmio + LTMODE_OFS, old_ltmode, ltmode); + mv_write_cached_reg(port_mmio + EDMA_HALTCOND_OFS, old_haltcond, haltcond); } static void mv_60x1_errata_sata25(struct ata_port *ap, int want_ncq) @@ -1235,7 +1282,7 @@ static void mv_edma_cfg(struct ata_port *ap, int want_ncq, int want_edma) */ want_fbs &= want_ncq; - mv_config_fbs(port_mmio, want_ncq, want_fbs); + mv_config_fbs(ap, want_ncq, want_fbs); if (want_fbs) { pp->pp_flags |= MV_PP_FLAG_FBS_EN; @@ -1339,6 +1386,7 @@ static int mv_port_start(struct ata_port *ap) pp->sg_tbl_dma[tag] = pp->sg_tbl_dma[0]; } } + mv_save_cached_regs(ap); mv_edma_cfg(ap, 0, 0); return 0; @@ -2997,6 +3045,7 @@ static int mv_hardreset(struct ata_link *link, unsigned int *class, extra = HZ; /* only extend it once, max */ } } while (sstatus != 0x0 && sstatus != 0x113 && sstatus != 0x123); + mv_save_cached_regs(ap); mv_edma_cfg(ap, 0, 0); return rc; |