https://github.com/torvalds/linux
Tip revision: caca6a03d365883564885f2c1da3e88dcf65d139 authored by Linus Torvalds on 24 November 2011, 04:20:28 UTC
Linux 3.2-rc3
Linux 3.2-rc3
Tip revision: caca6a0
cs5536.c
/*
* CS5536 PATA support
* (C) 2007 Martin K. Petersen <mkp@mkp.net>
* (C) 2009 Bartlomiej Zolnierkiewicz
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Documentation:
* Available from AMD web site.
*
* The IDE timing registers for the CS5536 live in the Geode Machine
* Specific Register file and not PCI config space. Most BIOSes
* virtualize the PCI registers so the chip looks like a standard IDE
* controller. Unfortunately not all implementations get this right.
* In particular some have problems with unaligned accesses to the
* virtualized PCI registers. This driver always does full dword
* writes to work around the issue. Also, in case of a bad BIOS this
* driver can be loaded with the "msr=1" parameter which forces using
* the Machine Specific Registers to configure the device.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/ide.h>
#include <asm/msr.h>
#define DRV_NAME "cs5536"
enum {
MSR_IDE_CFG = 0x51300010,
PCI_IDE_CFG = 0x40,
CFG = 0,
DTC = 2,
CAST = 3,
ETC = 4,
IDE_CFG_CHANEN = (1 << 1),
IDE_CFG_CABLE = (1 << 17) | (1 << 16),
IDE_D0_SHIFT = 24,
IDE_D1_SHIFT = 16,
IDE_DRV_MASK = 0xff,
IDE_CAST_D0_SHIFT = 6,
IDE_CAST_D1_SHIFT = 4,
IDE_CAST_DRV_MASK = 0x3,
IDE_CAST_CMD_SHIFT = 24,
IDE_CAST_CMD_MASK = 0xff,
IDE_ETC_UDMA_MASK = 0xc0,
};
static int use_msr;
static int cs5536_read(struct pci_dev *pdev, int reg, u32 *val)
{
if (unlikely(use_msr)) {
u32 dummy;
rdmsr(MSR_IDE_CFG + reg, *val, dummy);
return 0;
}
return pci_read_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
}
static int cs5536_write(struct pci_dev *pdev, int reg, int val)
{
if (unlikely(use_msr)) {
wrmsr(MSR_IDE_CFG + reg, val, 0);
return 0;
}
return pci_write_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
}
static void cs5536_program_dtc(ide_drive_t *drive, u8 tim)
{
struct pci_dev *pdev = to_pci_dev(drive->hwif->dev);
int dshift = (drive->dn & 1) ? IDE_D1_SHIFT : IDE_D0_SHIFT;
u32 dtc;
cs5536_read(pdev, DTC, &dtc);
dtc &= ~(IDE_DRV_MASK << dshift);
dtc |= tim << dshift;
cs5536_write(pdev, DTC, dtc);
}
/**
* cs5536_cable_detect - detect cable type
* @hwif: Port to detect on
*
* Perform cable detection for ATA66 capable cable.
*
* Returns a cable type.
*/
static u8 cs5536_cable_detect(ide_hwif_t *hwif)
{
struct pci_dev *pdev = to_pci_dev(hwif->dev);
u32 cfg;
cs5536_read(pdev, CFG, &cfg);
if (cfg & IDE_CFG_CABLE)
return ATA_CBL_PATA80;
else
return ATA_CBL_PATA40;
}
/**
* cs5536_set_pio_mode - PIO timing setup
* @hwif: ATA port
* @drive: ATA device
*/
static void cs5536_set_pio_mode(ide_hwif_t *hwif, ide_drive_t *drive)
{
static const u8 drv_timings[5] = {
0x98, 0x55, 0x32, 0x21, 0x20,
};
static const u8 addr_timings[5] = {
0x2, 0x1, 0x0, 0x0, 0x0,
};
static const u8 cmd_timings[5] = {
0x99, 0x92, 0x90, 0x22, 0x20,
};
struct pci_dev *pdev = to_pci_dev(hwif->dev);
ide_drive_t *pair = ide_get_pair_dev(drive);
int cshift = (drive->dn & 1) ? IDE_CAST_D1_SHIFT : IDE_CAST_D0_SHIFT;
unsigned long timings = (unsigned long)ide_get_drivedata(drive);
u32 cast;
const u8 pio = drive->pio_mode - XFER_PIO_0;
u8 cmd_pio = pio;
if (pair)
cmd_pio = min_t(u8, pio, pair->pio_mode - XFER_PIO_0);
timings &= (IDE_DRV_MASK << 8);
timings |= drv_timings[pio];
ide_set_drivedata(drive, (void *)timings);
cs5536_program_dtc(drive, drv_timings[pio]);
cs5536_read(pdev, CAST, &cast);
cast &= ~(IDE_CAST_DRV_MASK << cshift);
cast |= addr_timings[pio] << cshift;
cast &= ~(IDE_CAST_CMD_MASK << IDE_CAST_CMD_SHIFT);
cast |= cmd_timings[cmd_pio] << IDE_CAST_CMD_SHIFT;
cs5536_write(pdev, CAST, cast);
}
/**
* cs5536_set_dma_mode - DMA timing setup
* @hwif: ATA port
* @drive: ATA device
*/
static void cs5536_set_dma_mode(ide_hwif_t *hwif, ide_drive_t *drive)
{
static const u8 udma_timings[6] = {
0xc2, 0xc1, 0xc0, 0xc4, 0xc5, 0xc6,
};
static const u8 mwdma_timings[3] = {
0x67, 0x21, 0x20,
};
struct pci_dev *pdev = to_pci_dev(hwif->dev);
int dshift = (drive->dn & 1) ? IDE_D1_SHIFT : IDE_D0_SHIFT;
unsigned long timings = (unsigned long)ide_get_drivedata(drive);
u32 etc;
const u8 mode = drive->dma_mode;
cs5536_read(pdev, ETC, &etc);
if (mode >= XFER_UDMA_0) {
etc &= ~(IDE_DRV_MASK << dshift);
etc |= udma_timings[mode - XFER_UDMA_0] << dshift;
} else { /* MWDMA */
etc &= ~(IDE_ETC_UDMA_MASK << dshift);
timings &= IDE_DRV_MASK;
timings |= mwdma_timings[mode - XFER_MW_DMA_0] << 8;
ide_set_drivedata(drive, (void *)timings);
}
cs5536_write(pdev, ETC, etc);
}
static void cs5536_dma_start(ide_drive_t *drive)
{
unsigned long timings = (unsigned long)ide_get_drivedata(drive);
if (drive->current_speed < XFER_UDMA_0 &&
(timings >> 8) != (timings & IDE_DRV_MASK))
cs5536_program_dtc(drive, timings >> 8);
ide_dma_start(drive);
}
static int cs5536_dma_end(ide_drive_t *drive)
{
int ret = ide_dma_end(drive);
unsigned long timings = (unsigned long)ide_get_drivedata(drive);
if (drive->current_speed < XFER_UDMA_0 &&
(timings >> 8) != (timings & IDE_DRV_MASK))
cs5536_program_dtc(drive, timings & IDE_DRV_MASK);
return ret;
}
static const struct ide_port_ops cs5536_port_ops = {
.set_pio_mode = cs5536_set_pio_mode,
.set_dma_mode = cs5536_set_dma_mode,
.cable_detect = cs5536_cable_detect,
};
static const struct ide_dma_ops cs5536_dma_ops = {
.dma_host_set = ide_dma_host_set,
.dma_setup = ide_dma_setup,
.dma_start = cs5536_dma_start,
.dma_end = cs5536_dma_end,
.dma_test_irq = ide_dma_test_irq,
.dma_lost_irq = ide_dma_lost_irq,
.dma_timer_expiry = ide_dma_sff_timer_expiry,
.dma_sff_read_status = ide_dma_sff_read_status,
};
static const struct ide_port_info cs5536_info = {
.name = DRV_NAME,
.port_ops = &cs5536_port_ops,
.dma_ops = &cs5536_dma_ops,
.host_flags = IDE_HFLAG_SINGLE,
.pio_mask = ATA_PIO4,
.mwdma_mask = ATA_MWDMA2,
.udma_mask = ATA_UDMA5,
};
/**
* cs5536_init_one
* @dev: PCI device
* @id: Entry in match table
*/
static int cs5536_init_one(struct pci_dev *dev, const struct pci_device_id *id)
{
u32 cfg;
if (use_msr)
printk(KERN_INFO DRV_NAME ": Using MSR regs instead of PCI\n");
cs5536_read(dev, CFG, &cfg);
if ((cfg & IDE_CFG_CHANEN) == 0) {
printk(KERN_ERR DRV_NAME ": disabled by BIOS\n");
return -ENODEV;
}
return ide_pci_init_one(dev, &cs5536_info, NULL);
}
static const struct pci_device_id cs5536_pci_tbl[] = {
{ PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_CS5536_IDE), },
{ },
};
static struct pci_driver cs5536_pci_driver = {
.name = DRV_NAME,
.id_table = cs5536_pci_tbl,
.probe = cs5536_init_one,
.remove = ide_pci_remove,
.suspend = ide_pci_suspend,
.resume = ide_pci_resume,
};
static int __init cs5536_init(void)
{
return pci_register_driver(&cs5536_pci_driver);
}
static void __exit cs5536_exit(void)
{
pci_unregister_driver(&cs5536_pci_driver);
}
MODULE_AUTHOR("Martin K. Petersen, Bartlomiej Zolnierkiewicz");
MODULE_DESCRIPTION("low-level driver for the CS5536 IDE controller");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, cs5536_pci_tbl);
module_param_named(msr, use_msr, int, 0644);
MODULE_PARM_DESC(msr, "Force using MSR to configure IDE function (Default: 0)");
module_init(cs5536_init);
module_exit(cs5536_exit);