--- /dev/null
+/*
+ * pata_cs5536.c       - CS5536 PATA for new ATA layer
+ *                       (C) 2007 Martin K. Petersen <mkp@mkp.net>
+ *
+ * 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/blkdev.h>
+#include <linux/delay.h>
+#include <linux/libata.h>
+#include <scsi/scsi_host.h>
+#include <asm/msr.h>
+
+#define DRV_NAME       "pata_cs5536"
+#define DRV_VERSION    "0.0.5"
+
+enum {
+       CFG                     = 0,
+       DTC                     = 1,
+       CAST                    = 2,
+       ETC                     = 3,
+
+       MSR_IDE_BASE            = 0x51300000,
+       MSR_IDE_CFG             = (MSR_IDE_BASE + 0x10),
+       MSR_IDE_DTC             = (MSR_IDE_BASE + 0x12),
+       MSR_IDE_CAST            = (MSR_IDE_BASE + 0x13),
+       MSR_IDE_ETC             = (MSR_IDE_BASE + 0x14),
+
+       PCI_IDE_CFG             = 0x40,
+       PCI_IDE_DTC             = 0x48,
+       PCI_IDE_CAST            = 0x4c,
+       PCI_IDE_ETC             = 0x50,
+
+       IDE_CFG_CHANEN          = 0x2,
+       IDE_CFG_CABLE           = 0x10000,
+
+       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_MASK       = 0xff,
+       IDE_CAST_CMD_SHIFT      = 24,
+
+       IDE_ETC_NODMA           = 0x03,
+};
+
+static int use_msr;
+
+static const u32 msr_reg[4] = {
+       MSR_IDE_CFG, MSR_IDE_DTC, MSR_IDE_CAST, MSR_IDE_ETC,
+};
+
+static const u8 pci_reg[4] = {
+       PCI_IDE_CFG, PCI_IDE_DTC, PCI_IDE_CAST, PCI_IDE_ETC,
+};
+
+static inline int cs5536_read(struct pci_dev *pdev, int reg, int *val)
+{
+       if (unlikely(use_msr)) {
+               u32 dummy;
+
+               rdmsr(msr_reg[reg], *val, dummy);
+               return 0;
+       }
+
+       return pci_read_config_dword(pdev, pci_reg[reg], val);
+}
+
+static inline int cs5536_write(struct pci_dev *pdev, int reg, int val)
+{
+       if (unlikely(use_msr)) {
+               wrmsr(msr_reg[reg], val, 0);
+               return 0;
+       }
+
+       return pci_write_config_dword(pdev, pci_reg[reg], val);
+}
+
+/**
+ *     cs5536_cable_detect     -       detect cable type
+ *     @ap: Port to detect on
+ *     @deadline: deadline jiffies for the operation
+ *
+ *     Perform cable detection for ATA66 capable cable. Return a libata
+ *     cable type.
+ */
+
+static int cs5536_cable_detect(struct ata_port *ap)
+{
+       struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+       u32 cfg;
+
+       cs5536_read(pdev, CFG, &cfg);
+
+       if (cfg & (IDE_CFG_CABLE << ap->port_no))
+               return ATA_CBL_PATA80;
+       else
+               return ATA_CBL_PATA40;
+}
+
+/**
+ *     cs5536_set_piomode              -       PIO setup
+ *     @ap: ATA interface
+ *     @adev: device on the interface
+ */
+
+static void cs5536_set_piomode(struct ata_port *ap, struct ata_device *adev)
+{
+       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(ap->host->dev);
+       struct ata_device *pair = ata_dev_pair(adev);
+       int mode = adev->pio_mode - XFER_PIO_0;
+       int cmdmode = mode;
+       int dshift = ap->port_no ? IDE_D1_SHIFT : IDE_D0_SHIFT;
+       int cshift = ap->port_no ? IDE_CAST_D1_SHIFT : IDE_CAST_D0_SHIFT;
+       u32 dtc, cast, etc;
+
+       if (pair)
+               cmdmode = min(mode, pair->pio_mode - XFER_PIO_0);
+
+       cs5536_read(pdev, DTC, &dtc);
+       cs5536_read(pdev, CAST, &cast);
+       cs5536_read(pdev, ETC, &etc);
+
+       dtc &= ~(IDE_DRV_MASK << dshift);
+       dtc |= drv_timings[mode] << dshift;
+
+       cast &= ~(IDE_CAST_DRV_MASK << cshift);
+       cast |= addr_timings[mode] << cshift;
+
+       cast &= ~(IDE_CAST_CMD_MASK << IDE_CAST_CMD_SHIFT);
+       cast |= cmd_timings[cmdmode] << IDE_CAST_CMD_SHIFT;
+
+       etc &= ~(IDE_DRV_MASK << dshift);
+       etc |= IDE_ETC_NODMA << dshift;
+
+       cs5536_write(pdev, DTC, dtc);
+       cs5536_write(pdev, CAST, cast);
+       cs5536_write(pdev, ETC, etc);
+}
+
+/**
+ *     cs5536_set_dmamode              -       DMA timing setup
+ *     @ap: ATA interface
+ *     @adev: Device being configured
+ *
+ */
+
+static void cs5536_set_dmamode(struct ata_port *ap, struct ata_device *adev)
+{
+       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(ap->host->dev);
+       u32 dtc, etc;
+       int mode = adev->dma_mode;
+       int dshift = ap->port_no ? IDE_D1_SHIFT : IDE_D0_SHIFT;
+
+       if (mode >= XFER_UDMA_0) {
+               cs5536_read(pdev, ETC, &etc);
+
+               etc &= ~(IDE_DRV_MASK << dshift);
+               etc |= udma_timings[mode - XFER_UDMA_0] << dshift;
+
+               cs5536_write(pdev, ETC, etc);
+       } else { /* MWDMA */
+               cs5536_read(pdev, DTC, &dtc);
+
+               dtc &= ~(IDE_DRV_MASK << dshift);
+               dtc |= mwdma_timings[mode] << dshift;
+
+               cs5536_write(pdev, DTC, dtc);
+       }
+}
+
+static struct scsi_host_template cs5536_sht = {
+       .module                 = THIS_MODULE,
+       .name                   = DRV_NAME,
+       .ioctl                  = ata_scsi_ioctl,
+       .queuecommand           = ata_scsi_queuecmd,
+       .can_queue              = ATA_DEF_QUEUE,
+       .this_id                = ATA_SHT_THIS_ID,
+       .sg_tablesize           = LIBATA_MAX_PRD,
+       .cmd_per_lun            = ATA_SHT_CMD_PER_LUN,
+       .emulated               = ATA_SHT_EMULATED,
+       .use_clustering         = ATA_SHT_USE_CLUSTERING,
+       .proc_name              = DRV_NAME,
+       .dma_boundary           = ATA_DMA_BOUNDARY,
+       .slave_configure        = ata_scsi_slave_config,
+       .slave_destroy          = ata_scsi_slave_destroy,
+       .bios_param             = ata_std_bios_param,
+};
+
+static struct ata_port_operations cs5536_port_ops = {
+       .port_disable           = ata_port_disable,
+       .set_piomode            = cs5536_set_piomode,
+       .set_dmamode            = cs5536_set_dmamode,
+       .mode_filter            = ata_pci_default_filter,
+
+       .tf_load                = ata_tf_load,
+       .tf_read                = ata_tf_read,
+       .check_status           = ata_check_status,
+       .exec_command           = ata_exec_command,
+       .dev_select             = ata_std_dev_select,
+
+       .freeze                 = ata_bmdma_freeze,
+       .thaw                   = ata_bmdma_thaw,
+       .error_handler          = ata_bmdma_error_handler,
+       .post_internal_cmd      = ata_bmdma_post_internal_cmd,
+       .cable_detect           = cs5536_cable_detect,
+
+       .bmdma_setup            = ata_bmdma_setup,
+       .bmdma_start            = ata_bmdma_start,
+       .bmdma_stop             = ata_bmdma_stop,
+       .bmdma_status           = ata_bmdma_status,
+
+       .qc_prep                = ata_qc_prep,
+       .qc_issue               = ata_qc_issue_prot,
+
+       .data_xfer              = ata_data_xfer,
+
+       .irq_handler            = ata_interrupt,
+       .irq_clear              = ata_bmdma_irq_clear,
+       .irq_on                 = ata_irq_on,
+       .irq_ack                = ata_irq_ack,
+
+       .port_start             = ata_port_start,
+};
+
+/**
+ *     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)
+{
+       static const struct ata_port_info info = {
+               .sht = &cs5536_sht,
+               .flags = ATA_FLAG_SLAVE_POSS,
+               .pio_mask = 0x1f,
+               .mwdma_mask = 0x07,
+               .udma_mask = ATA_UDMA5,
+               .port_ops = &cs5536_port_ops,
+       };
+
+       const struct ata_port_info *ppi[] = { &info, &ata_dummy_port_info };
+       u32 cfg;
+
+       if (use_msr)
+               printk(KERN_ERR 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 ata_pci_init_one(dev, ppi);
+}
+
+static const struct pci_device_id cs5536[] = {
+       { PCI_VDEVICE(AMD,      PCI_DEVICE_ID_AMD_CS5536_IDE), },
+       { },
+};
+
+static struct pci_driver cs5536_pci_driver = {
+       .name           = DRV_NAME,
+       .id_table       = cs5536,
+       .probe          = cs5536_init_one,
+       .remove         = ata_pci_remove_one,
+#ifdef CONFIG_PM
+       .suspend        = ata_pci_device_suspend,
+       .resume         = ata_pci_device_resume,
+#endif
+};
+
+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");
+MODULE_DESCRIPTION("low-level driver for the CS5536 IDE controller");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(pci, cs5536);
+MODULE_VERSION(DRV_VERSION);
+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);