kernel_optimize_test/drivers/ata/pata_marvell.c
Tejun Heo 029cfd6b74 libata: implement and use ops inheritance
libata lets low level drivers build ata_port_operations table and
register it with libata core layer.  This allows low level drivers
high level of flexibility but also burdens them with lots of
boilerplate entries.

This becomes worse for drivers which support related similar
controllers which differ slightly.  They share most of the operations
except for a few.  However, the driver still needs to list all
operations for each variant.  This results in large number of
duplicate entries, which is not only inefficient but also error-prone
as it becomes very difficult to tell what the actual differences are.

This duplicate boilerplates all over the low level drivers also make
updating the core layer exteremely difficult and error-prone.  When
compounded with multi-branched development model, it ends up
accumulating inconsistencies over time.  Some of those inconsistencies
cause immediate problems and fixed.  Others just remain there dormant
making maintenance increasingly difficult.

To rectify the problem, this patch implements ata_port_operations
inheritance.  To allow LLDs to easily re-use their own ops tables
overriding only specific methods, this patch implements poor man's
class inheritance.  An ops table has ->inherits field which can be set
to any ops table as long as it doesn't create a loop.  When the host
is started, the inheritance chain is followed and any operation which
isn't specified is taken from the nearest ancestor which has it
specified.  This operation is called finalization and done only once
per an ops table and the LLD doesn't have to do anything special about
it other than making the ops table non-const such that libata can
update it.

libata provides four base ops tables lower drivers can inherit from -
base, sata, pmp, sff and bmdma.  To avoid overriding these ops
accidentaly, these ops are declared const and LLDs should always
inherit these instead of using them directly.

After finalization, all the ops table are identical before and after
the patch except for setting .irq_handler to ata_interrupt in drivers
which didn't use to.  The .irq_handler doesn't have any actual effect
and the field will soon be removed by later patch.

* sata_sx4 is still using old style EH and currently doesn't take
  advantage of ops inheritance.

Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17 15:44:17 -04:00

188 lines
4.1 KiB
C

/*
* Marvell PATA driver.
*
* For the moment we drive the PATA port in legacy mode. That
* isn't making full use of the device functionality but it is
* easy to get working.
*
* (c) 2006 Red Hat <alan@redhat.com>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <scsi/scsi_host.h>
#include <linux/libata.h>
#include <linux/ata.h>
#define DRV_NAME "pata_marvell"
#define DRV_VERSION "0.1.4"
/**
* marvell_pre_reset - check for 40/80 pin
* @link: link
* @deadline: deadline jiffies for the operation
*
* Perform the PATA port setup we need.
*/
static int marvell_pre_reset(struct ata_link *link, unsigned long deadline)
{
struct ata_port *ap = link->ap;
struct pci_dev *pdev = to_pci_dev(ap->host->dev);
u32 devices;
void __iomem *barp;
int i;
/* Check if our port is enabled */
barp = pci_iomap(pdev, 5, 0x10);
if (barp == NULL)
return -ENOMEM;
printk("BAR5:");
for(i = 0; i <= 0x0F; i++)
printk("%02X:%02X ", i, ioread8(barp + i));
printk("\n");
devices = ioread32(barp + 0x0C);
pci_iounmap(pdev, barp);
if ((pdev->device == 0x6145) && (ap->port_no == 0) &&
(!(devices & 0x10))) /* PATA enable ? */
return -ENOENT;
return ata_std_prereset(link, deadline);
}
static int marvell_cable_detect(struct ata_port *ap)
{
/* Cable type */
switch(ap->port_no)
{
case 0:
if (ioread8(ap->ioaddr.bmdma_addr + 1) & 1)
return ATA_CBL_PATA40;
return ATA_CBL_PATA80;
case 1: /* Legacy SATA port */
return ATA_CBL_SATA;
}
BUG();
return 0; /* Our BUG macro needs the right markup */
}
/**
* marvell_error_handler - Setup and error handler
* @ap: Port to handle
*
* LOCKING:
* None (inherited from caller).
*/
static void marvell_error_handler(struct ata_port *ap)
{
ata_bmdma_drive_eh(ap, marvell_pre_reset, ata_std_softreset, NULL,
ata_std_postreset);
}
/* No PIO or DMA methods needed for this device */
static struct scsi_host_template marvell_sht = {
ATA_BMDMA_SHT(DRV_NAME),
};
static struct ata_port_operations marvell_ops = {
.inherits = &ata_bmdma_port_ops,
.cable_detect = marvell_cable_detect,
.error_handler = marvell_error_handler,
};
/**
* marvell_init_one - Register Marvell ATA PCI device with kernel services
* @pdev: PCI device to register
* @ent: Entry in marvell_pci_tbl matching with @pdev
*
* Called from kernel PCI layer.
*
* LOCKING:
* Inherited from PCI layer (may sleep).
*
* RETURNS:
* Zero on success, or -ERRNO value.
*/
static int marvell_init_one (struct pci_dev *pdev, const struct pci_device_id *id)
{
static const struct ata_port_info info = {
.sht = &marvell_sht,
.flags = ATA_FLAG_SLAVE_POSS,
.pio_mask = 0x1f,
.mwdma_mask = 0x07,
.udma_mask = ATA_UDMA5,
.port_ops = &marvell_ops,
};
static const struct ata_port_info info_sata = {
.sht = &marvell_sht,
/* Slave possible as its magically mapped not real */
.flags = ATA_FLAG_SLAVE_POSS,
.pio_mask = 0x1f,
.mwdma_mask = 0x07,
.udma_mask = ATA_UDMA6,
.port_ops = &marvell_ops,
};
const struct ata_port_info *ppi[] = { &info, &info_sata };
if (pdev->device == 0x6101)
ppi[1] = &ata_dummy_port_info;
return ata_pci_init_one(pdev, ppi);
}
static const struct pci_device_id marvell_pci_tbl[] = {
{ PCI_DEVICE(0x11AB, 0x6101), },
{ PCI_DEVICE(0x11AB, 0x6121), },
{ PCI_DEVICE(0x11AB, 0x6123), },
{ PCI_DEVICE(0x11AB, 0x6145), },
{ } /* terminate list */
};
static struct pci_driver marvell_pci_driver = {
.name = DRV_NAME,
.id_table = marvell_pci_tbl,
.probe = marvell_init_one,
.remove = ata_pci_remove_one,
#ifdef CONFIG_PM
.suspend = ata_pci_device_suspend,
.resume = ata_pci_device_resume,
#endif
};
static int __init marvell_init(void)
{
return pci_register_driver(&marvell_pci_driver);
}
static void __exit marvell_exit(void)
{
pci_unregister_driver(&marvell_pci_driver);
}
module_init(marvell_init);
module_exit(marvell_exit);
MODULE_AUTHOR("Alan Cox");
MODULE_DESCRIPTION("SCSI low-level driver for Marvell ATA in legacy mode");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, marvell_pci_tbl);
MODULE_VERSION(DRV_VERSION);