root/drivers/ata/pata_opti.c

DEFINITIONS

1. opti_pre_reset
2. opti_write_reg
3. opti_set_piomode
4. opti_init_one

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * pata_opti.c  - ATI PATA for new ATA layer
   4  *                        (C) 2005 Red Hat Inc
   5  *
   6  * Based on
   7  *  linux/drivers/ide/pci/opti621.c             Version 0.7     Sept 10, 2002
   8  *
   9  *  Copyright (C) 1996-1998  Linus Torvalds & authors (see below)
  10  *
  11  * Authors:
  12  * Jaromir Koutek <miri@punknet.cz>,
  13  * Jan Harkes <jaharkes@cwi.nl>,
  14  * Mark Lord <mlord@pobox.com>
  15  * Some parts of code are from ali14xx.c and from rz1000.c.
  16  *
  17  * Also consulted the FreeBSD prototype driver by Kevin Day to try
  18  * and resolve some confusions. Further documentation can be found in
  19  * Ralf Brown's interrupt list
  20  *
  21  * If you have other variants of the Opti range (Viper/Vendetta) please
  22  * try this driver with those PCI idents and report back. For the later
  23  * chips see the pata_optidma driver
  24  *
  25  */
  26 
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/pci.h>
  30 #include <linux/blkdev.h>
  31 #include <linux/delay.h>
  32 #include <scsi/scsi_host.h>
  33 #include <linux/libata.h>
  34 
  35 #define DRV_NAME "pata_opti"
  36 #define DRV_VERSION "0.2.9"
  37 
  38 enum {
  39         READ_REG        = 0,    /* index of Read cycle timing register */
  40         WRITE_REG       = 1,    /* index of Write cycle timing register */
  41         CNTRL_REG       = 3,    /* index of Control register */
  42         STRAP_REG       = 5,    /* index of Strap register */
  43         MISC_REG        = 6     /* index of Miscellaneous register */
  44 };
  45 
  46 /**
  47  *      opti_pre_reset          -       probe begin
  48  *      @link: ATA link
  49  *      @deadline: deadline jiffies for the operation
  50  *
  51  *      Set up cable type and use generic probe init
  52  */
  53 
  54 static int opti_pre_reset(struct ata_link *link, unsigned long deadline)
  55 {
  56         struct ata_port *ap = link->ap;
  57         struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  58         static const struct pci_bits opti_enable_bits[] = {
  59                 { 0x45, 1, 0x80, 0x00 },
  60                 { 0x40, 1, 0x08, 0x00 }
  61         };
  62 
  63         if (!pci_test_config_bits(pdev, &opti_enable_bits[ap->port_no]))
  64                 return -ENOENT;
  65 
  66         return ata_sff_prereset(link, deadline);
  67 }
  68 
  69 /**
  70  *      opti_write_reg          -       control register setup
  71  *      @ap: ATA port
  72  *      @value: value
  73  *      @reg: control register number
  74  *
  75  *      The Opti uses magic 'trapdoor' register accesses to do configuration
  76  *      rather than using PCI space as other controllers do. The double inw
  77  *      on the error register activates configuration mode. We can then write
  78  *      the control register
  79  */
  80 
  81 static void opti_write_reg(struct ata_port *ap, u8 val, int reg)
  82 {
  83         void __iomem *regio = ap->ioaddr.cmd_addr;
  84 
  85         /* These 3 unlock the control register access */
  86         ioread16(regio + 1);
  87         ioread16(regio + 1);
  88         iowrite8(3, regio + 2);
  89 
  90         /* Do the I/O */
  91         iowrite8(val, regio + reg);
  92 
  93         /* Relock */
  94         iowrite8(0x83, regio + 2);
  95 }
  96 
  97 /**
  98  *      opti_set_piomode        -       set initial PIO mode data
  99  *      @ap: ATA interface
 100  *      @adev: ATA device
 101  *
 102  *      Called to do the PIO mode setup. Timing numbers are taken from
 103  *      the FreeBSD driver then pre computed to keep the code clean. There
 104  *      are two tables depending on the hardware clock speed.
 105  */
 106 
 107 static void opti_set_piomode(struct ata_port *ap, struct ata_device *adev)
 108 {
 109         struct ata_device *pair = ata_dev_pair(adev);
 110         int clock;
 111         int pio = adev->pio_mode - XFER_PIO_0;
 112         void __iomem *regio = ap->ioaddr.cmd_addr;
 113         u8 addr;
 114 
 115         /* Address table precomputed with prefetch off and a DCLK of 2 */
 116         static const u8 addr_timing[2][5] = {
 117                 { 0x30, 0x20, 0x20, 0x10, 0x10 },
 118                 { 0x20, 0x20, 0x10, 0x10, 0x10 }
 119         };
 120         static const u8 data_rec_timing[2][5] = {
 121                 { 0x6B, 0x56, 0x42, 0x32, 0x31 },
 122                 { 0x58, 0x44, 0x32, 0x22, 0x21 }
 123         };
 124 
 125         iowrite8(0xff, regio + 5);
 126         clock = ioread16(regio + 5) & 1;
 127 
 128         /*
 129          *      As with many controllers the address setup time is shared
 130          *      and must suit both devices if present.
 131          */
 132 
 133         addr = addr_timing[clock][pio];
 134         if (pair) {
 135                 /* Hardware constraint */
 136                 u8 pair_addr = addr_timing[clock][pair->pio_mode - XFER_PIO_0];
 137                 if (pair_addr > addr)
 138                         addr = pair_addr;
 139         }
 140 
 141         /* Commence primary programming sequence */
 142         opti_write_reg(ap, adev->devno, MISC_REG);
 143         opti_write_reg(ap, data_rec_timing[clock][pio], READ_REG);
 144         opti_write_reg(ap, data_rec_timing[clock][pio], WRITE_REG);
 145         opti_write_reg(ap, addr, MISC_REG);
 146 
 147         /* Programming sequence complete, override strapping */
 148         opti_write_reg(ap, 0x85, CNTRL_REG);
 149 }
 150 
 151 static struct scsi_host_template opti_sht = {
 152         ATA_PIO_SHT(DRV_NAME),
 153 };
 154 
 155 static struct ata_port_operations opti_port_ops = {
 156         .inherits       = &ata_sff_port_ops,
 157         .cable_detect   = ata_cable_40wire,
 158         .set_piomode    = opti_set_piomode,
 159         .prereset       = opti_pre_reset,
 160 };
 161 
 162 static int opti_init_one(struct pci_dev *dev, const struct pci_device_id *id)
 163 {
 164         static const struct ata_port_info info = {
 165                 .flags = ATA_FLAG_SLAVE_POSS,
 166                 .pio_mask = ATA_PIO4,
 167                 .port_ops = &opti_port_ops
 168         };
 169         const struct ata_port_info *ppi[] = { &info, NULL };
 170 
 171         ata_print_version_once(&dev->dev, DRV_VERSION);
 172 
 173         return ata_pci_sff_init_one(dev, ppi, &opti_sht, NULL, 0);
 174 }
 175 
 176 static const struct pci_device_id opti[] = {
 177         { PCI_VDEVICE(OPTI, PCI_DEVICE_ID_OPTI_82C621), 0 },
 178         { PCI_VDEVICE(OPTI, PCI_DEVICE_ID_OPTI_82C825), 1 },
 179 
 180         { },
 181 };
 182 
 183 static struct pci_driver opti_pci_driver = {
 184         .name           = DRV_NAME,
 185         .id_table       = opti,
 186         .probe          = opti_init_one,
 187         .remove         = ata_pci_remove_one,
 188 #ifdef CONFIG_PM_SLEEP
 189         .suspend        = ata_pci_device_suspend,
 190         .resume         = ata_pci_device_resume,
 191 #endif
 192 };
 193 
 194 module_pci_driver(opti_pci_driver);
 195 
 196 MODULE_AUTHOR("Alan Cox");
 197 MODULE_DESCRIPTION("low-level driver for Opti 621/621X");
 198 MODULE_LICENSE("GPL");
 199 MODULE_DEVICE_TABLE(pci, opti);
 200 MODULE_VERSION(DRV_VERSION);