root/drivers/ata/pata_sch.c

DEFINITIONS

1. sch_set_piomode
2. sch_set_dmamode
3. sch_init_one

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  pata_sch.c - Intel SCH PATA controllers
   4  *
   5  *  Copyright (c) 2008 Alek Du <alek.du@intel.com>
   6  */
   7 
   8 /*
   9  *  Supports:
  10  *    Intel SCH (AF82US15W, AF82US15L, AF82UL11L) chipsets -- see spec at:
  11  *    http://download.intel.com/design/chipsets/embedded/datashts/319537.pdf
  12  */
  13 
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/pci.h>
  17 #include <linux/blkdev.h>
  18 #include <linux/delay.h>
  19 #include <linux/device.h>
  20 #include <scsi/scsi_host.h>
  21 #include <linux/libata.h>
  22 #include <linux/dmi.h>
  23 
  24 #define DRV_NAME        "pata_sch"
  25 #define DRV_VERSION     "0.2"
  26 
  27 /* see SCH datasheet page 351 */
  28 enum {
  29         D0TIM   = 0x80,         /* Device 0 Timing Register */
  30         D1TIM   = 0x84,         /* Device 1 Timing Register */
  31         PM      = 0x07,         /* PIO Mode Bit Mask */
  32         MDM     = (0x03 << 8),  /* Multi-word DMA Mode Bit Mask */
  33         UDM     = (0x07 << 16), /* Ultra DMA Mode Bit Mask */
  34         PPE     = (1 << 30),    /* Prefetch/Post Enable */
  35         USD     = (1 << 31),    /* Use Synchronous DMA */
  36 };
  37 
  38 static int sch_init_one(struct pci_dev *pdev,
  39                          const struct pci_device_id *ent);
  40 static void sch_set_piomode(struct ata_port *ap, struct ata_device *adev);
  41 static void sch_set_dmamode(struct ata_port *ap, struct ata_device *adev);
  42 
  43 static const struct pci_device_id sch_pci_tbl[] = {
  44         /* Intel SCH PATA Controller */
  45         { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_SCH_IDE), 0 },
  46         { }     /* terminate list */
  47 };
  48 
  49 static struct pci_driver sch_pci_driver = {
  50         .name                   = DRV_NAME,
  51         .id_table               = sch_pci_tbl,
  52         .probe                  = sch_init_one,
  53         .remove                 = ata_pci_remove_one,
  54 #ifdef CONFIG_PM_SLEEP
  55         .suspend                = ata_pci_device_suspend,
  56         .resume                 = ata_pci_device_resume,
  57 #endif
  58 };
  59 
  60 static struct scsi_host_template sch_sht = {
  61         ATA_BMDMA_SHT(DRV_NAME),
  62 };
  63 
  64 static struct ata_port_operations sch_pata_ops = {
  65         .inherits               = &ata_bmdma_port_ops,
  66         .cable_detect           = ata_cable_unknown,
  67         .set_piomode            = sch_set_piomode,
  68         .set_dmamode            = sch_set_dmamode,
  69 };
  70 
  71 static const struct ata_port_info sch_port_info = {
  72         .flags          = ATA_FLAG_SLAVE_POSS,
  73         .pio_mask       = ATA_PIO4,
  74         .mwdma_mask     = ATA_MWDMA2,
  75         .udma_mask      = ATA_UDMA5,
  76         .port_ops       = &sch_pata_ops,
  77 };
  78 
  79 MODULE_AUTHOR("Alek Du <alek.du@intel.com>");
  80 MODULE_DESCRIPTION("SCSI low-level driver for Intel SCH PATA controllers");
  81 MODULE_LICENSE("GPL");
  82 MODULE_DEVICE_TABLE(pci, sch_pci_tbl);
  83 MODULE_VERSION(DRV_VERSION);
  84 
  85 /**
  86  *      sch_set_piomode - Initialize host controller PATA PIO timings
  87  *      @ap: Port whose timings we are configuring
  88  *      @adev: ATA device
  89  *
  90  *      Set PIO mode for device, in host controller PCI config space.
  91  *
  92  *      LOCKING:
  93  *      None (inherited from caller).
  94  */
  95 
  96 static void sch_set_piomode(struct ata_port *ap, struct ata_device *adev)
  97 {
  98         unsigned int pio        = adev->pio_mode - XFER_PIO_0;
  99         struct pci_dev *dev     = to_pci_dev(ap->host->dev);
 100         unsigned int port       = adev->devno ? D1TIM : D0TIM;
 101         unsigned int data;
 102 
 103         pci_read_config_dword(dev, port, &data);
 104         /* see SCH datasheet page 351 */
 105         /* set PIO mode */
 106         data &= ~(PM | PPE);
 107         data |= pio;
 108         /* enable PPE for block device */
 109         if (adev->class == ATA_DEV_ATA)
 110                 data |= PPE;
 111         pci_write_config_dword(dev, port, data);
 112 }
 113 
 114 /**
 115  *      sch_set_dmamode - Initialize host controller PATA DMA timings
 116  *      @ap: Port whose timings we are configuring
 117  *      @adev: ATA device
 118  *
 119  *      Set MW/UDMA mode for device, in host controller PCI config space.
 120  *
 121  *      LOCKING:
 122  *      None (inherited from caller).
 123  */
 124 
 125 static void sch_set_dmamode(struct ata_port *ap, struct ata_device *adev)
 126 {
 127         unsigned int dma_mode   = adev->dma_mode;
 128         struct pci_dev *dev     = to_pci_dev(ap->host->dev);
 129         unsigned int port       = adev->devno ? D1TIM : D0TIM;
 130         unsigned int data;
 131 
 132         pci_read_config_dword(dev, port, &data);
 133         /* see SCH datasheet page 351 */
 134         if (dma_mode >= XFER_UDMA_0) {
 135                 /* enable Synchronous DMA mode */
 136                 data |= USD;
 137                 data &= ~UDM;
 138                 data |= (dma_mode - XFER_UDMA_0) << 16;
 139         } else { /* must be MWDMA mode, since we masked SWDMA already */
 140                 data &= ~(USD | MDM);
 141                 data |= (dma_mode - XFER_MW_DMA_0) << 8;
 142         }
 143         pci_write_config_dword(dev, port, data);
 144 }
 145 
 146 /**
 147  *      sch_init_one - Register SCH ATA PCI device with kernel services
 148  *      @pdev: PCI device to register
 149  *      @ent: Entry in sch_pci_tbl matching with @pdev
 150  *
 151  *      LOCKING:
 152  *      Inherited from PCI layer (may sleep).
 153  *
 154  *      RETURNS:
 155  *      Zero on success, or -ERRNO value.
 156  */
 157 
 158 static int sch_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 159 {
 160         const struct ata_port_info *ppi[] = { &sch_port_info, NULL };
 161 
 162         ata_print_version_once(&pdev->dev, DRV_VERSION);
 163 
 164         return ata_pci_bmdma_init_one(pdev, ppi, &sch_sht, NULL, 0);
 165 }
 166 
 167 module_pci_driver(sch_pci_driver);