android_kernel_xiaomi_sm8350/drivers/ata/pata_at32.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

409 lines
10 KiB
C

/*
* AVR32 SMC/CFC PATA Driver
*
* Copyright (C) 2007 Atmel Norway
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*/
#define DEBUG
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <scsi/scsi_host.h>
#include <linux/ata.h>
#include <linux/libata.h>
#include <linux/err.h>
#include <linux/io.h>
#include <asm/arch/board.h>
#include <asm/arch/smc.h>
#define DRV_NAME "pata_at32"
#define DRV_VERSION "0.0.3"
/*
* CompactFlash controller memory layout relative to the base address:
*
* Attribute memory: 0000 0000 -> 003f ffff
* Common memory: 0040 0000 -> 007f ffff
* I/O memory: 0080 0000 -> 00bf ffff
* True IDE Mode: 00c0 0000 -> 00df ffff
* Alt IDE Mode: 00e0 0000 -> 00ff ffff
*
* Only True IDE and Alt True IDE mode are needed for this driver.
*
* True IDE mode => CS0 = 0, CS1 = 1 (cmd, error, stat, etc)
* Alt True IDE mode => CS0 = 1, CS1 = 0 (ctl, alt_stat)
*/
#define CF_IDE_OFFSET 0x00c00000
#define CF_ALT_IDE_OFFSET 0x00e00000
#define CF_RES_SIZE 2048
/*
* Define DEBUG_BUS if you are doing debugging of your own EBI -> PATA
* adaptor with a logic analyzer or similar.
*/
#undef DEBUG_BUS
/*
* ATA PIO modes
*
* Name | Mb/s | Min cycle time | Mask
* --------+-------+----------------+--------
* Mode 0 | 3.3 | 600 ns | 0x01
* Mode 1 | 5.2 | 383 ns | 0x03
* Mode 2 | 8.3 | 240 ns | 0x07
* Mode 3 | 11.1 | 180 ns | 0x0f
* Mode 4 | 16.7 | 120 ns | 0x1f
*
* Alter PIO_MASK below according to table to set maximal PIO mode.
*/
#define PIO_MASK (0x1f)
/*
* Struct containing private information about device.
*/
struct at32_ide_info {
unsigned int irq;
struct resource res_ide;
struct resource res_alt;
void __iomem *ide_addr;
void __iomem *alt_addr;
unsigned int cs;
struct smc_config smc;
};
/*
* Setup SMC for the given ATA timing.
*/
static int pata_at32_setup_timing(struct device *dev,
struct at32_ide_info *info,
const struct ata_timing *ata)
{
struct smc_config *smc = &info->smc;
struct smc_timing timing;
int active;
int recover;
memset(&timing, 0, sizeof(struct smc_timing));
/* Total cycle time */
timing.read_cycle = ata->cyc8b;
/* DIOR <= CFIOR timings */
timing.nrd_setup = ata->setup;
timing.nrd_pulse = ata->act8b;
timing.nrd_recover = ata->rec8b;
/* Convert nanosecond timing to clock cycles */
smc_set_timing(smc, &timing);
/* Add one extra cycle setup due to signal ring */
smc->nrd_setup = smc->nrd_setup + 1;
active = smc->nrd_setup + smc->nrd_pulse;
recover = smc->read_cycle - active;
/* Need at least two cycles recovery */
if (recover < 2)
smc->read_cycle = active + 2;
/* (CS0, CS1, DIR, OE) <= (CFCE1, CFCE2, CFRNW, NCSX) timings */
smc->ncs_read_setup = 1;
smc->ncs_read_pulse = smc->read_cycle - 2;
/* Write timings same as read timings */
smc->write_cycle = smc->read_cycle;
smc->nwe_setup = smc->nrd_setup;
smc->nwe_pulse = smc->nrd_pulse;
smc->ncs_write_setup = smc->ncs_read_setup;
smc->ncs_write_pulse = smc->ncs_read_pulse;
/* Do some debugging output of ATA and SMC timings */
dev_dbg(dev, "ATA: C=%d S=%d P=%d R=%d\n",
ata->cyc8b, ata->setup, ata->act8b, ata->rec8b);
dev_dbg(dev, "SMC: C=%d S=%d P=%d NS=%d NP=%d\n",
smc->read_cycle, smc->nrd_setup, smc->nrd_pulse,
smc->ncs_read_setup, smc->ncs_read_pulse);
/* Finally, configure the SMC */
return smc_set_configuration(info->cs, smc);
}
/*
* Procedures for libATA.
*/
static void pata_at32_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
struct ata_timing timing;
struct at32_ide_info *info = ap->host->private_data;
int ret;
/* Compute ATA timing */
ret = ata_timing_compute(adev, adev->pio_mode, &timing, 1000, 0);
if (ret) {
dev_warn(ap->dev, "Failed to compute ATA timing %d\n", ret);
return;
}
/* Setup SMC to ATA timing */
ret = pata_at32_setup_timing(ap->dev, info, &timing);
if (ret) {
dev_warn(ap->dev, "Failed to setup ATA timing %d\n", ret);
return;
}
}
static struct scsi_host_template at32_sht = {
ATA_PIO_SHT(DRV_NAME),
};
static struct ata_port_operations at32_port_ops = {
.inherits = &ata_sff_port_ops,
.cable_detect = ata_cable_40wire,
.set_piomode = pata_at32_set_piomode,
};
static int __init pata_at32_init_one(struct device *dev,
struct at32_ide_info *info)
{
struct ata_host *host;
struct ata_port *ap;
host = ata_host_alloc(dev, 1);
if (!host)
return -ENOMEM;
ap = host->ports[0];
/* Setup ATA bindings */
ap->ops = &at32_port_ops;
ap->pio_mask = PIO_MASK;
ap->flags |= ATA_FLAG_MMIO | ATA_FLAG_SLAVE_POSS;
/*
* Since all 8-bit taskfile transfers has to go on the lower
* byte of the data bus and there is a bug in the SMC that
* makes it impossible to alter the bus width during runtime,
* we need to hardwire the address signals as follows:
*
* A_IDE(2:0) <= A_EBI(3:1)
*
* This makes all addresses on the EBI even, thus all data
* will be on the lower byte of the data bus. All addresses
* used by libATA need to be altered according to this.
*/
ap->ioaddr.altstatus_addr = info->alt_addr + (0x06 << 1);
ap->ioaddr.ctl_addr = info->alt_addr + (0x06 << 1);
ap->ioaddr.data_addr = info->ide_addr + (ATA_REG_DATA << 1);
ap->ioaddr.error_addr = info->ide_addr + (ATA_REG_ERR << 1);
ap->ioaddr.feature_addr = info->ide_addr + (ATA_REG_FEATURE << 1);
ap->ioaddr.nsect_addr = info->ide_addr + (ATA_REG_NSECT << 1);
ap->ioaddr.lbal_addr = info->ide_addr + (ATA_REG_LBAL << 1);
ap->ioaddr.lbam_addr = info->ide_addr + (ATA_REG_LBAM << 1);
ap->ioaddr.lbah_addr = info->ide_addr + (ATA_REG_LBAH << 1);
ap->ioaddr.device_addr = info->ide_addr + (ATA_REG_DEVICE << 1);
ap->ioaddr.status_addr = info->ide_addr + (ATA_REG_STATUS << 1);
ap->ioaddr.command_addr = info->ide_addr + (ATA_REG_CMD << 1);
/* Set info as private data of ATA host */
host->private_data = info;
/* Register ATA device and return */
return ata_host_activate(host, info->irq, ata_interrupt,
IRQF_SHARED | IRQF_TRIGGER_RISING,
&at32_sht);
}
/*
* This function may come in handy for people analyzing their own
* EBI -> PATA adaptors.
*/
#ifdef DEBUG_BUS
static void __init pata_at32_debug_bus(struct device *dev,
struct at32_ide_info *info)
{
const int d1 = 0xff;
const int d2 = 0x00;
int i;
/* Write 8-bit values (registers) */
iowrite8(d1, info->alt_addr + (0x06 << 1));
iowrite8(d2, info->alt_addr + (0x06 << 1));
for (i = 0; i < 8; i++) {
iowrite8(d1, info->ide_addr + (i << 1));
iowrite8(d2, info->ide_addr + (i << 1));
}
/* Write 16 bit values (data) */
iowrite16(d1, info->ide_addr);
iowrite16(d1 << 8, info->ide_addr);
iowrite16(d1, info->ide_addr);
iowrite16(d1 << 8, info->ide_addr);
}
#endif
static int __init pata_at32_probe(struct platform_device *pdev)
{
const struct ata_timing initial_timing =
{XFER_PIO_0, 70, 290, 240, 600, 165, 150, 600, 0};
struct device *dev = &pdev->dev;
struct at32_ide_info *info;
struct ide_platform_data *board = pdev->dev.platform_data;
struct resource *res;
int irq;
int ret;
if (!board)
return -ENXIO;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENXIO;
/* Retrive IRQ */
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
/* Setup struct containing private information */
info = kzalloc(sizeof(struct at32_ide_info), GFP_KERNEL);
if (!info)
return -ENOMEM;
memset(info, 0, sizeof(struct at32_ide_info));
info->irq = irq;
info->cs = board->cs;
/* Request memory resources */
info->res_ide.start = res->start + CF_IDE_OFFSET;
info->res_ide.end = info->res_ide.start + CF_RES_SIZE - 1;
info->res_ide.name = "ide";
info->res_ide.flags = IORESOURCE_MEM;
ret = request_resource(res, &info->res_ide);
if (ret)
goto err_req_res_ide;
info->res_alt.start = res->start + CF_ALT_IDE_OFFSET;
info->res_alt.end = info->res_alt.start + CF_RES_SIZE - 1;
info->res_alt.name = "alt";
info->res_alt.flags = IORESOURCE_MEM;
ret = request_resource(res, &info->res_alt);
if (ret)
goto err_req_res_alt;
/* Setup non-timing elements of SMC */
info->smc.bus_width = 2; /* 16 bit data bus */
info->smc.nrd_controlled = 1; /* Sample data on rising edge of NRD */
info->smc.nwe_controlled = 0; /* Drive data on falling edge of NCS */
info->smc.nwait_mode = 3; /* NWAIT is in READY mode */
info->smc.byte_write = 0; /* Byte select access type */
info->smc.tdf_mode = 0; /* TDF optimization disabled */
info->smc.tdf_cycles = 0; /* No TDF wait cycles */
/* Setup SMC to ATA timing */
ret = pata_at32_setup_timing(dev, info, &initial_timing);
if (ret)
goto err_setup_timing;
/* Map ATA address space */
ret = -ENOMEM;
info->ide_addr = devm_ioremap(dev, info->res_ide.start, 16);
info->alt_addr = devm_ioremap(dev, info->res_alt.start, 16);
if (!info->ide_addr || !info->alt_addr)
goto err_ioremap;
#ifdef DEBUG_BUS
pata_at32_debug_bus(dev, info);
#endif
/* Setup and register ATA device */
ret = pata_at32_init_one(dev, info);
if (ret)
goto err_ata_device;
return 0;
err_ata_device:
err_ioremap:
err_setup_timing:
release_resource(&info->res_alt);
err_req_res_alt:
release_resource(&info->res_ide);
err_req_res_ide:
kfree(info);
return ret;
}
static int __exit pata_at32_remove(struct platform_device *pdev)
{
struct ata_host *host = platform_get_drvdata(pdev);
struct at32_ide_info *info;
if (!host)
return 0;
info = host->private_data;
ata_host_detach(host);
if (!info)
return 0;
release_resource(&info->res_ide);
release_resource(&info->res_alt);
kfree(info);
return 0;
}
static struct platform_driver pata_at32_driver = {
.remove = __exit_p(pata_at32_remove),
.driver = {
.name = "at32_ide",
.owner = THIS_MODULE,
},
};
static int __init pata_at32_init(void)
{
return platform_driver_probe(&pata_at32_driver, pata_at32_probe);
}
static void __exit pata_at32_exit(void)
{
platform_driver_unregister(&pata_at32_driver);
}
module_init(pata_at32_init);
module_exit(pata_at32_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("AVR32 SMC/CFC PATA Driver");
MODULE_AUTHOR("Kristoffer Nyborg Gregertsen <kngregertsen@norway.atmel.com>");
MODULE_VERSION(DRV_VERSION);