korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-18 01:34:14 +08:00
Code Issues Packages Projects Releases Wiki Activity
8decec78a3
linux/drivers/ide/tx4938ide.c
Atsushi Nemoto 7afa05350c tx4938ide: Avoid underflow on calculation of a wait cycle 
Make 'wt' variable signed while it can be negative during calculation.

Suggested-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: sshtylyov@ru.mvista.com
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2008-11-02 21:40:10 +01:00

324 lines
9.1 KiB
C
Raw Blame History

/*
* TX4938 internal IDE driver
* Based on tx4939ide.c.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* (C) Copyright TOSHIBA CORPORATION 2005-2007
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/ide.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <asm/txx9/tx4938.h>
static void tx4938ide_tune_ebusc(unsigned int ebus_ch,
unsigned int gbus_clock,
u8 pio)
{
struct ide_timing *t = ide_timing_find_mode(XFER_PIO_0 + pio);
u64 cr = __raw_readq(&tx4938_ebuscptr->cr[ebus_ch]);
unsigned int sp = (cr >> 4) & 3;
unsigned int clock = gbus_clock / (4 - sp);
unsigned int cycle = 1000000000 / clock;
unsigned int shwt;
int wt;
/* Minimum DIOx- active time */
wt = DIV_ROUND_UP(t->act8b, cycle) - 2;
/* IORDY setup time: 35ns */
wt = max_t(int, wt, DIV_ROUND_UP(35, cycle));
/* actual wait-cycle is max(wt & ~1, 1) */
if (wt > 2 && (wt & 1))
wt++;
wt &= ~1;
/* Address-valid to DIOR/DIOW setup */
shwt = DIV_ROUND_UP(t->setup, cycle);
/* -DIOx recovery time (SHWT * 4) and cycle time requirement */
while ((shwt * 4 + wt + (wt ? 2 : 3)) * cycle < t->cycle)
shwt++;
if (shwt > 7) {
pr_warning("tx4938ide: SHWT violation (%d)\n", shwt);
shwt = 7;
}
pr_debug("tx4938ide: ebus %d, bus cycle %dns, WT %d, SHWT %d\n",
ebus_ch, cycle, wt, shwt);
__raw_writeq((cr & ~0x3f007ull) | (wt << 12) | shwt,
&tx4938_ebuscptr->cr[ebus_ch]);
}
static void tx4938ide_set_pio_mode(ide_drive_t *drive, const u8 pio)
{
ide_hwif_t *hwif = drive->hwif;
struct tx4938ide_platform_info *pdata = hwif->dev->platform_data;
u8 safe = pio;
ide_drive_t *pair;
pair = ide_get_pair_dev(drive);
if (pair)
safe = min(safe, ide_get_best_pio_mode(pair, 255, 5));
tx4938ide_tune_ebusc(pdata->ebus_ch, pdata->gbus_clock, safe);
}
#ifdef __BIG_ENDIAN
/* custom iops (independent from SWAP_IO_SPACE) */
static u8 tx4938ide_inb(unsigned long port)
{
return __raw_readb((void __iomem *)port);
}
static void tx4938ide_outb(u8 value, unsigned long port)
{
__raw_writeb(value, (void __iomem *)port);
}
static void tx4938ide_tf_load(ide_drive_t *drive, ide_task_t *task)
{
ide_hwif_t *hwif = drive->hwif;
struct ide_io_ports *io_ports = &hwif->io_ports;
struct ide_taskfile *tf = &task->tf;
u8 HIHI = task->tf_flags & IDE_TFLAG_LBA48 ? 0xE0 : 0xEF;
if (task->tf_flags & IDE_TFLAG_FLAGGED)
HIHI = 0xFF;
if (task->tf_flags & IDE_TFLAG_OUT_DATA) {
u16 data = (tf->hob_data << 8) | tf->data;
/* no endian swap */
__raw_writew(data, (void __iomem *)io_ports->data_addr);
}
if (task->tf_flags & IDE_TFLAG_OUT_HOB_FEATURE)
tx4938ide_outb(tf->hob_feature, io_ports->feature_addr);
if (task->tf_flags & IDE_TFLAG_OUT_HOB_NSECT)
tx4938ide_outb(tf->hob_nsect, io_ports->nsect_addr);
if (task->tf_flags & IDE_TFLAG_OUT_HOB_LBAL)
tx4938ide_outb(tf->hob_lbal, io_ports->lbal_addr);
if (task->tf_flags & IDE_TFLAG_OUT_HOB_LBAM)
tx4938ide_outb(tf->hob_lbam, io_ports->lbam_addr);
if (task->tf_flags & IDE_TFLAG_OUT_HOB_LBAH)
tx4938ide_outb(tf->hob_lbah, io_ports->lbah_addr);
if (task->tf_flags & IDE_TFLAG_OUT_FEATURE)
tx4938ide_outb(tf->feature, io_ports->feature_addr);
if (task->tf_flags & IDE_TFLAG_OUT_NSECT)
tx4938ide_outb(tf->nsect, io_ports->nsect_addr);
if (task->tf_flags & IDE_TFLAG_OUT_LBAL)
tx4938ide_outb(tf->lbal, io_ports->lbal_addr);
if (task->tf_flags & IDE_TFLAG_OUT_LBAM)
tx4938ide_outb(tf->lbam, io_ports->lbam_addr);
if (task->tf_flags & IDE_TFLAG_OUT_LBAH)
tx4938ide_outb(tf->lbah, io_ports->lbah_addr);
if (task->tf_flags & IDE_TFLAG_OUT_DEVICE)
tx4938ide_outb((tf->device & HIHI) | drive->select,
io_ports->device_addr);
}
static void tx4938ide_tf_read(ide_drive_t *drive, ide_task_t *task)
{
ide_hwif_t *hwif = drive->hwif;
struct ide_io_ports *io_ports = &hwif->io_ports;
struct ide_taskfile *tf = &task->tf;
if (task->tf_flags & IDE_TFLAG_IN_DATA) {
u16 data;
/* no endian swap */
data = __raw_readw((void __iomem *)io_ports->data_addr);
tf->data = data & 0xff;
tf->hob_data = (data >> 8) & 0xff;
}
/* be sure we're looking at the low order bits */
tx4938ide_outb(ATA_DEVCTL_OBS & ~0x80, io_ports->ctl_addr);
if (task->tf_flags & IDE_TFLAG_IN_FEATURE)
tf->feature = tx4938ide_inb(io_ports->feature_addr);
if (task->tf_flags & IDE_TFLAG_IN_NSECT)
tf->nsect = tx4938ide_inb(io_ports->nsect_addr);
if (task->tf_flags & IDE_TFLAG_IN_LBAL)
tf->lbal = tx4938ide_inb(io_ports->lbal_addr);
if (task->tf_flags & IDE_TFLAG_IN_LBAM)
tf->lbam = tx4938ide_inb(io_ports->lbam_addr);
if (task->tf_flags & IDE_TFLAG_IN_LBAH)
tf->lbah = tx4938ide_inb(io_ports->lbah_addr);
if (task->tf_flags & IDE_TFLAG_IN_DEVICE)
tf->device = tx4938ide_inb(io_ports->device_addr);
if (task->tf_flags & IDE_TFLAG_LBA48) {
tx4938ide_outb(ATA_DEVCTL_OBS | 0x80, io_ports->ctl_addr);
if (task->tf_flags & IDE_TFLAG_IN_HOB_FEATURE)
tf->hob_feature =
tx4938ide_inb(io_ports->feature_addr);
if (task->tf_flags & IDE_TFLAG_IN_HOB_NSECT)
tf->hob_nsect = tx4938ide_inb(io_ports->nsect_addr);
if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAL)
tf->hob_lbal = tx4938ide_inb(io_ports->lbal_addr);
if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAM)
tf->hob_lbam = tx4938ide_inb(io_ports->lbam_addr);
if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAH)
tf->hob_lbah = tx4938ide_inb(io_ports->lbah_addr);
}
}
static void tx4938ide_input_data_swap(ide_drive_t *drive, struct request *rq,
void *buf, unsigned int len)
{
unsigned long port = drive->hwif->io_ports.data_addr;
unsigned short *ptr = buf;
unsigned int count = (len + 1) / 2;
while (count--)
*ptr++ = cpu_to_le16(__raw_readw((void __iomem *)port));
__ide_flush_dcache_range((unsigned long)buf, count * 2);
}
static void tx4938ide_output_data_swap(ide_drive_t *drive, struct request *rq,
void *buf, unsigned int len)
{
unsigned long port = drive->hwif->io_ports.data_addr;
unsigned short *ptr = buf;
unsigned int count = (len + 1) / 2;
while (count--) {
__raw_writew(le16_to_cpu(*ptr), (void __iomem *)port);
ptr++;
}
__ide_flush_dcache_range((unsigned long)buf, count * 2);
}
static const struct ide_tp_ops tx4938ide_tp_ops = {
.exec_command = ide_exec_command,
.read_status = ide_read_status,
.read_altstatus = ide_read_altstatus,
.read_sff_dma_status = ide_read_sff_dma_status,
.set_irq = ide_set_irq,
.tf_load = tx4938ide_tf_load,
.tf_read = tx4938ide_tf_read,
.input_data = tx4938ide_input_data_swap,
.output_data = tx4938ide_output_data_swap,
};
#endif /* __BIG_ENDIAN */
static const struct ide_port_ops tx4938ide_port_ops = {
.set_pio_mode = tx4938ide_set_pio_mode,
};
static const struct ide_port_info tx4938ide_port_info __initdata = {
.port_ops = &tx4938ide_port_ops,
#ifdef __BIG_ENDIAN
.tp_ops = &tx4938ide_tp_ops,
#endif
.host_flags = IDE_HFLAG_MMIO | IDE_HFLAG_NO_DMA,
.pio_mask = ATA_PIO5,
};
static int __init tx4938ide_probe(struct platform_device *pdev)
{
hw_regs_t hw;
hw_regs_t *hws[] = { &hw, NULL, NULL, NULL };
struct ide_host *host;
struct resource *res;
struct tx4938ide_platform_info *pdata = pdev->dev.platform_data;
int irq, ret, i;
unsigned long mapbase, mapctl;
struct ide_port_info d = tx4938ide_port_info;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return -ENODEV;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENODEV;
if (!devm_request_mem_region(&pdev->dev, res->start,
res->end - res->start + 1, "tx4938ide"))
return -EBUSY;
mapbase = (unsigned long)devm_ioremap(&pdev->dev, res->start,
8 << pdata->ioport_shift);
mapctl = (unsigned long)devm_ioremap(&pdev->dev,
res->start + 0x10000 +
(6 << pdata->ioport_shift),
1 << pdata->ioport_shift);
if (!mapbase || !mapctl)
return -EBUSY;
memset(&hw, 0, sizeof(hw));
if (pdata->ioport_shift) {
unsigned long port = mapbase;
unsigned long ctl = mapctl;
hw.io_ports_array[0] = port;
#ifdef __BIG_ENDIAN
port++;
ctl++;
#endif
for (i = 1; i <= 7; i++)
hw.io_ports_array[i] =
port + (i << pdata->ioport_shift);
hw.io_ports.ctl_addr = ctl;
} else
ide_std_init_ports(&hw, mapbase, mapctl);
hw.irq = irq;
hw.dev = &pdev->dev;
pr_info("TX4938 IDE interface (base %#lx, ctl %#lx, irq %d)\n",
mapbase, mapctl, hw.irq);
if (pdata->gbus_clock)
tx4938ide_tune_ebusc(pdata->ebus_ch, pdata->gbus_clock, 0);
else
d.port_ops = NULL;
ret = ide_host_add(&d, hws, &host);
if (!ret)
platform_set_drvdata(pdev, host);
return ret;
}
static int __exit tx4938ide_remove(struct platform_device *pdev)
{
struct ide_host *host = platform_get_drvdata(pdev);
ide_host_remove(host);
return 0;
}
static struct platform_driver tx4938ide_driver = {
.driver = {
.name = "tx4938ide",
.owner = THIS_MODULE,
},
.remove = __exit_p(tx4938ide_remove),
};
static int __init tx4938ide_init(void)
{
return platform_driver_probe(&tx4938ide_driver, tx4938ide_probe);
}
static void __exit tx4938ide_exit(void)
{
platform_driver_unregister(&tx4938ide_driver);
}
module_init(tx4938ide_init);
module_exit(tx4938ide_exit);
MODULE_DESCRIPTION("TX4938 internal IDE driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:tx4938ide");
Reference in New Issue View Git Blame Copy Permalink