From: Brett Russ Date: Wed, 5 Oct 2005 21:08:53 +0000 (-0400) Subject: [PATCH] libata: Marvell function headers X-Git-Tag: v2.6.15-rc1~736^2~7 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=05b308e1df6d9d673daedb517969241f41278b52;p=linux-2.6 [PATCH] libata: Marvell function headers adds helpful function header comments. Signed-off-by: Brett Russ Signed-off-by: Jeff Garzik --- diff --git a/drivers/scsi/sata_mv.c b/drivers/scsi/sata_mv.c index c3084f8b3e..84b488f81c 100644 --- a/drivers/scsi/sata_mv.c +++ b/drivers/scsi/sata_mv.c @@ -35,7 +35,7 @@ #include #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;