[PATCH] libata: Marvell function headers

adds helpful function header comments.

Signed-off-by: Brett Russ <russb@emc.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
This commit is contained in:
Brett Russ 2005-10-05 17:08:53 -04:00 committed by Jeff Garzik
parent afb0edd922
commit 05b308e1df

View File

@ -35,7 +35,7 @@
#include <asm/io.h>
#define DRV_NAME "sata_mv"
#define DRV_VERSION "0.23"
#define DRV_VERSION "0.24"
enum {
/* BAR's are enumerated in terms of pci_resource_start() terms */
@ -406,6 +406,17 @@ static void mv_irq_clear(struct ata_port *ap)
{
}
/**
* mv_start_dma - Enable eDMA engine
* @base: port base address
* @pp: port private data
*
* Verify the local cache of the eDMA state is accurate with an
* assert.
*
* LOCKING:
* Inherited from caller.
*/
static void mv_start_dma(void __iomem *base, struct mv_port_priv *pp)
{
if (!(MV_PP_FLAG_EDMA_EN & pp->pp_flags)) {
@ -415,6 +426,16 @@ static void mv_start_dma(void __iomem *base, struct mv_port_priv *pp)
assert(EDMA_EN & readl(base + EDMA_CMD_OFS));
}
/**
* mv_stop_dma - Disable eDMA engine
* @ap: ATA channel to manipulate
*
* Verify the local cache of the eDMA state is accurate with an
* assert.
*
* LOCKING:
* Inherited from caller.
*/
static void mv_stop_dma(struct ata_port *ap)
{
void __iomem *port_mmio = mv_ap_base(ap);
@ -561,7 +582,15 @@ static void mv_scr_write(struct ata_port *ap, unsigned int sc_reg_in, u32 val)
}
}
/* This routine only applies to 6xxx parts */
/**
* mv_global_soft_reset - Perform the 6xxx global soft reset
* @mmio_base: base address of the HBA
*
* This routine only applies to 6xxx parts.
*
* LOCKING:
* Inherited from caller.
*/
static int mv_global_soft_reset(void __iomem *mmio_base)
{
void __iomem *reg = mmio_base + PCI_MAIN_CMD_STS_OFS;
@ -617,6 +646,16 @@ done:
return rc;
}
/**
* mv_host_stop - Host specific cleanup/stop routine.
* @host_set: host data structure
*
* Disable ints, cleanup host memory, call general purpose
* host_stop.
*
* LOCKING:
* Inherited from caller.
*/
static void mv_host_stop(struct ata_host_set *host_set)
{
struct mv_host_priv *hpriv = host_set->private_data;
@ -631,6 +670,16 @@ static void mv_host_stop(struct ata_host_set *host_set)
ata_host_stop(host_set);
}
/**
* mv_port_start - Port specific init/start routine.
* @ap: ATA channel to manipulate
*
* Allocate and point to DMA memory, init port private memory,
* zero indices.
*
* LOCKING:
* Inherited from caller.
*/
static int mv_port_start(struct ata_port *ap)
{
struct device *dev = ap->host_set->dev;
@ -699,6 +748,15 @@ static int mv_port_start(struct ata_port *ap)
return 0;
}
/**
* mv_port_stop - Port specific cleanup/stop routine.
* @ap: ATA channel to manipulate
*
* Stop DMA, cleanup port memory.
*
* LOCKING:
* This routine uses the host_set lock to protect the DMA stop.
*/
static void mv_port_stop(struct ata_port *ap)
{
struct device *dev = ap->host_set->dev;
@ -714,6 +772,15 @@ static void mv_port_stop(struct ata_port *ap)
kfree(pp);
}
/**
* mv_fill_sg - Fill out the Marvell ePRD (scatter gather) entries
* @qc: queued command whose SG list to source from
*
* Populate the SG list and mark the last entry.
*
* LOCKING:
* Inherited from caller.
*/
static void mv_fill_sg(struct ata_queued_cmd *qc)
{
struct mv_port_priv *pp = qc->ap->private_data;
@ -748,6 +815,18 @@ static inline void mv_crqb_pack_cmd(u16 *cmdw, u8 data, u8 addr, unsigned last)
(last ? CRQB_CMD_LAST : 0);
}
/**
* mv_qc_prep - Host specific command preparation.
* @qc: queued command to prepare
*
* This routine simply redirects to the general purpose routine
* if command is not DMA. Else, it handles prep of the CRQB
* (command request block), does some sanity checking, and calls
* the SG load routine.
*
* LOCKING:
* Inherited from caller.
*/
static void mv_qc_prep(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
@ -830,6 +909,18 @@ static void mv_qc_prep(struct ata_queued_cmd *qc)
mv_fill_sg(qc);
}
/**
* mv_qc_issue - Initiate a command to the host
* @qc: queued command to start
*
* This routine simply redirects to the general purpose routine
* if command is not DMA. Else, it sanity checks our local
* caches of the request producer/consumer indices then enables
* DMA and bumps the request producer index.
*
* LOCKING:
* Inherited from caller.
*/
static int mv_qc_issue(struct ata_queued_cmd *qc)
{
void __iomem *port_mmio = mv_ap_base(qc->ap);
@ -867,6 +958,19 @@ static int mv_qc_issue(struct ata_queued_cmd *qc)
return 0;
}
/**
* mv_get_crpb_status - get status from most recently completed cmd
* @ap: ATA channel to manipulate
*
* This routine is for use when the port is in DMA mode, when it
* will be using the CRPB (command response block) method of
* returning command completion information. We assert indices
* are good, grab status, and bump the response consumer index to
* prove that we're up to date.
*
* LOCKING:
* Inherited from caller.
*/
static u8 mv_get_crpb_status(struct ata_port *ap)
{
void __iomem *port_mmio = mv_ap_base(ap);
@ -896,6 +1000,19 @@ static u8 mv_get_crpb_status(struct ata_port *ap)
return (pp->crpb[pp->rsp_consumer].flags >> CRPB_FLAG_STATUS_SHIFT);
}
/**
* mv_err_intr - Handle error interrupts on the port
* @ap: ATA channel to manipulate
*
* In most cases, just clear the interrupt and move on. However,
* some cases require an eDMA reset, which is done right before
* the COMRESET in mv_phy_reset(). The SERR case requires a
* clear of pending errors in the SATA SERROR register. Finally,
* if the port disabled DMA, update our cached copy to match.
*
* LOCKING:
* Inherited from caller.
*/
static void mv_err_intr(struct ata_port *ap)
{
void __iomem *port_mmio = mv_ap_base(ap);
@ -923,7 +1040,22 @@ static void mv_err_intr(struct ata_port *ap)
}
}
/* Handle any outstanding interrupts in a single SATAHC */
/**
* mv_host_intr - Handle all interrupts on the given host controller
* @host_set: host specific structure
* @relevant: port error bits relevant to this host controller
* @hc: which host controller we're to look at
*
* Read then write clear the HC interrupt status then walk each
* port connected to the HC and see if it needs servicing. Port
* success ints are reported in the HC interrupt status reg, the
* port error ints are reported in the higher level main
* interrupt status register and thus are passed in via the
* 'relevant' argument.
*
* LOCKING:
* Inherited from caller.
*/
static void mv_host_intr(struct ata_host_set *host_set, u32 relevant,
unsigned int hc)
{
@ -993,6 +1125,21 @@ static void mv_host_intr(struct ata_host_set *host_set, u32 relevant,
VPRINTK("EXIT\n");
}
/**
* mv_interrupt -
* @irq: unused
* @dev_instance: private data; in this case the host structure
* @regs: unused
*
* Read the read only register to determine if any host
* controllers have pending interrupts. If so, call lower level
* routine to handle. Also check for PCI errors which are only
* reported here.
*
* LOCKING:
* This routine holds the host_set lock while processing pending
* interrupts.
*/
static irqreturn_t mv_interrupt(int irq, void *dev_instance,
struct pt_regs *regs)
{
@ -1035,14 +1182,32 @@ static irqreturn_t mv_interrupt(int irq, void *dev_instance,
return IRQ_RETVAL(handled);
}
/**
* mv_check_err - Return the error shadow register to caller.
* @ap: ATA channel to manipulate
*
* Marvell requires DMA to be stopped before accessing shadow
* registers. So we do that, then return the needed register.
*
* LOCKING:
* Inherited from caller. FIXME: protect mv_stop_dma with lock?
*/
static u8 mv_check_err(struct ata_port *ap)
{
mv_stop_dma(ap); /* can't read shadow regs if DMA on */
return readb((void __iomem *) ap->ioaddr.error_addr);
}
/* Part of this is taken from __sata_phy_reset and modified to not sleep
* since this routine gets called from interrupt level.
/**
* mv_phy_reset - Perform eDMA reset followed by COMRESET
* @ap: ATA channel to manipulate
*
* Part of this is taken from __sata_phy_reset and modified to
* not sleep since this routine gets called from interrupt level.
*
* LOCKING:
* Inherited from caller. This is coded to safe to call at
* interrupt level, i.e. it does not sleep.
*/
static void mv_phy_reset(struct ata_port *ap)
{
@ -1105,6 +1270,16 @@ static void mv_phy_reset(struct ata_port *ap)
VPRINTK("EXIT\n");
}
/**
* mv_eng_timeout - Routine called by libata when SCSI times out I/O
* @ap: ATA channel to manipulate
*
* Intent is to clear all pending error conditions, reset the
* chip/bus, fail the command, and move on.
*
* LOCKING:
* This routine holds the host_set lock while failing the command.
*/
static void mv_eng_timeout(struct ata_port *ap)
{
struct ata_queued_cmd *qc;
@ -1140,6 +1315,18 @@ static void mv_eng_timeout(struct ata_port *ap)
}
}
/**
* mv_port_init - Perform some early initialization on a single port.
* @port: libata data structure storing shadow register addresses
* @port_mmio: base address of the port
*
* Initialize shadow register mmio addresses, clear outstanding
* interrupts on the port, and unmask interrupts for the future
* start of the port.
*
* LOCKING:
* Inherited from caller.
*/
static void mv_port_init(struct ata_ioports *port, void __iomem *port_mmio)
{
unsigned long shd_base = (unsigned long) port_mmio + SHD_BLK_OFS;
@ -1177,6 +1364,16 @@ static void mv_port_init(struct ata_ioports *port, void __iomem *port_mmio)
readl(port_mmio + EDMA_ERR_IRQ_MASK_OFS));
}
/**
* mv_host_init - Perform some early initialization of the host.
* @probe_ent: early data struct representing the host
*
* If possible, do an early global reset of the host. Then do
* our port init and clear/unmask all/relevant host interrupts.
*
* LOCKING:
* Inherited from caller.
*/
static int mv_host_init(struct ata_probe_ent *probe_ent)
{
int rc = 0, n_hc, port, hc;
@ -1226,7 +1423,15 @@ done:
return rc;
}
/* FIXME: complete this */
/**
* mv_print_info - Dump key info to kernel log for perusal.
* @probe_ent: early data struct representing the host
*
* FIXME: complete this.
*
* LOCKING:
* Inherited from caller.
*/
static void mv_print_info(struct ata_probe_ent *probe_ent)
{
struct pci_dev *pdev = to_pci_dev(probe_ent->dev);
@ -1253,6 +1458,14 @@ static void mv_print_info(struct ata_probe_ent *probe_ent)
scc_s, (MV_HP_FLAG_MSI & hpriv->hp_flags) ? "MSI" : "INTx");
}
/**
* mv_init_one - handle a positive probe of a Marvell host
* @pdev: PCI device found
* @ent: PCI device ID entry for the matched host
*
* LOCKING:
* Inherited from caller.
*/
static int mv_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
{
static int printed_version = 0;