[libata] sata_mv: minor cleanups
* trim trailing whitespace
* document some flags, registers, and register bits
* fix locking around EDMA on/off and configuration
* continue replacing "constant OP var" with "var OP constant"
* use new pci_try_set_mwi()
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c
index 0ccd990..80ade5b 100644
--- a/drivers/ata/sata_mv.c
+++ b/drivers/ata/sata_mv.c
@@ -35,8 +35,6 @@
6) Add port multiplier support (intermediate)
- 7) Test and verify 3.0 Gbps support
-
8) Develop a low-power-consumption strategy, and implement it.
9) [Experiment, low priority] See if ATAPI can be supported using
@@ -286,10 +284,10 @@
EDMA_RSP_Q_OUT_PTR_OFS = 0x24, /* also contains BASE_LO */
EDMA_RSP_Q_PTR_SHIFT = 3,
- EDMA_CMD_OFS = 0x28,
- EDMA_EN = (1 << 0),
- EDMA_DS = (1 << 1),
- ATA_RST = (1 << 2),
+ EDMA_CMD_OFS = 0x28, /* EDMA command register */
+ EDMA_EN = (1 << 0), /* enable EDMA */
+ EDMA_DS = (1 << 1), /* disable EDMA; self-negated */
+ ATA_RST = (1 << 2), /* reset trans/link/phy */
EDMA_IORDY_TMOUT = 0x34,
EDMA_ARB_CFG = 0x38,
@@ -301,14 +299,13 @@
MV_HP_ERRATA_60X1B2 = (1 << 3),
MV_HP_ERRATA_60X1C0 = (1 << 4),
MV_HP_ERRATA_XX42A0 = (1 << 5),
- MV_HP_GEN_I = (1 << 6),
- MV_HP_GEN_II = (1 << 7),
- MV_HP_GEN_IIE = (1 << 8),
+ MV_HP_GEN_I = (1 << 6), /* Generation I: 50xx */
+ MV_HP_GEN_II = (1 << 7), /* Generation II: 60xx */
+ MV_HP_GEN_IIE = (1 << 8), /* Generation IIE: 6042/7042 */
/* Port private flags (pp_flags) */
- MV_PP_FLAG_EDMA_EN = (1 << 0),
- MV_PP_FLAG_EDMA_DS_ACT = (1 << 1),
- MV_PP_FLAG_HAD_A_RESET = (1 << 2),
+ MV_PP_FLAG_EDMA_EN = (1 << 0), /* is EDMA engine enabled? */
+ MV_PP_FLAG_HAD_A_RESET = (1 << 2), /* 1st hard reset complete? */
};
#define IS_GEN_I(hpriv) ((hpriv)->hp_flags & MV_HP_GEN_I)
@@ -318,8 +315,12 @@
enum {
MV_DMA_BOUNDARY = 0xffffffffU,
+ /* mask of register bits containing lower 32 bits
+ * of EDMA request queue DMA address
+ */
EDMA_REQ_Q_BASE_LO_MASK = 0xfffffc00U,
+ /* ditto, for response queue */
EDMA_RSP_Q_BASE_LO_MASK = 0xffffff00U,
};
@@ -823,7 +824,7 @@
}
/**
- * mv_stop_dma - Disable eDMA engine
+ * __mv_stop_dma - Disable eDMA engine
* @ap: ATA channel to manipulate
*
* Verify the local cache of the eDMA state is accurate with a
@@ -832,7 +833,7 @@
* LOCKING:
* Inherited from caller.
*/
-static int mv_stop_dma(struct ata_port *ap)
+static int __mv_stop_dma(struct ata_port *ap)
{
void __iomem *port_mmio = mv_ap_base(ap);
struct mv_port_priv *pp = ap->private_data;
@@ -865,6 +866,18 @@
return err;
}
+static int mv_stop_dma(struct ata_port *ap)
+{
+ unsigned long flags;
+ int rc;
+
+ spin_lock_irqsave(&ap->host->lock, flags);
+ rc = __mv_stop_dma(ap);
+ spin_unlock_irqrestore(&ap->host->lock, flags);
+
+ return rc;
+}
+
#ifdef ATA_DEBUG
static void mv_dump_mem(void __iomem *start, unsigned bytes)
{
@@ -965,7 +978,7 @@
{
unsigned int ofs = mv_scr_offset(sc_reg_in);
- if (0xffffffffU != ofs)
+ if (ofs != 0xffffffffU)
return readl(mv_ap_base(ap) + ofs);
else
return (u32) ofs;
@@ -975,7 +988,7 @@
{
unsigned int ofs = mv_scr_offset(sc_reg_in);
- if (0xffffffffU != ofs)
+ if (ofs != 0xffffffffU)
writelfl(val, mv_ap_base(ap) + ofs);
}
@@ -1029,6 +1042,7 @@
void __iomem *port_mmio = mv_ap_base(ap);
void *mem;
dma_addr_t mem_dma;
+ unsigned long flags;
int rc;
pp = devm_kzalloc(dev, sizeof(*pp), GFP_KERNEL);
@@ -1067,10 +1081,14 @@
pp->sg_tbl = mem;
pp->sg_tbl_dma = mem_dma;
+ spin_lock_irqsave(&ap->host->lock, flags);
+
mv_edma_cfg(ap, hpriv, port_mmio);
mv_set_edma_ptrs(port_mmio, hpriv, pp);
+ spin_unlock_irqrestore(&ap->host->lock, flags);
+
/* Don't turn on EDMA here...do it before DMA commands only. Else
* we'll be unable to send non-data, PIO, etc due to restricted access
* to shadow regs.
@@ -1090,11 +1108,7 @@
*/
static void mv_port_stop(struct ata_port *ap)
{
- unsigned long flags;
-
- spin_lock_irqsave(&ap->host->lock, flags);
mv_stop_dma(ap);
- spin_unlock_irqrestore(&ap->host->lock, flags);
}
/**
@@ -1325,7 +1339,7 @@
* port. Turn off EDMA so there won't be problems accessing
* shadow block, etc registers.
*/
- mv_stop_dma(ap);
+ __mv_stop_dma(ap);
return ata_qc_issue_prot(qc);
}
@@ -1497,7 +1511,7 @@
break;
/* 50xx: get active ATA command */
- if (IS_GEN_I(hpriv))
+ if (IS_GEN_I(hpriv))
tag = ap->active_tag;
/* Gen II/IIE: get active ATA command via tag, to enable
@@ -1532,7 +1546,7 @@
ata_qc_complete(qc);
}
- /* advance software response queue pointer, to
+ /* advance software response queue pointer, to
* indicate (after the loop completes) to hardware
* that we have consumed a response queue entry.
*/
@@ -2206,7 +2220,7 @@
struct mv_port_priv *pp = ap->private_data;
struct ata_eh_context *ehc = &ap->eh_context;
int rc;
-
+
rc = mv_stop_dma(ap);
if (rc)
ehc->i.action |= ATA_EH_HARDRESET;