root/drivers/ata/pata_cmd640.c

DEFINITIONS

1. cmd640_set_piomode
2. cmd640_qc_issue
3. cmd640_port_start
4. cmd640_sff_irq_check
5. cmd640_hardware_init
6. cmd640_init_one
7. cmd640_reinit_one

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * pata_cmd640.c        - CMD640 PCI PATA for new ATA layer
   4  *                        (C) 2007 Red Hat Inc
   5  *
   6  * Based upon
   7  *  linux/drivers/ide/pci/cmd640.c              Version 1.02  Sep 01, 1996
   8  *
   9  *  Copyright (C) 1995-1996  Linus Torvalds & authors (see driver)
  10  *
  11  *      This drives only the PCI version of the controller. If you have a
  12  *      VLB one then we have enough docs to support it but you can write
  13  *      your own code.
  14  */
  15 
  16 #include <linux/kernel.h>
  17 #include <linux/module.h>
  18 #include <linux/pci.h>
  19 #include <linux/blkdev.h>
  20 #include <linux/delay.h>
  21 #include <linux/gfp.h>
  22 #include <scsi/scsi_host.h>
  23 #include <linux/libata.h>
  24 
  25 #define DRV_NAME "pata_cmd640"
  26 #define DRV_VERSION "0.0.5"
  27 
  28 struct cmd640_reg {
  29         int last;
  30         u8 reg58[ATA_MAX_DEVICES];
  31 };
  32 
  33 enum {
  34         CFR = 0x50,
  35         CNTRL = 0x51,
  36         CMDTIM = 0x52,
  37         ARTIM0 = 0x53,
  38         DRWTIM0 = 0x54,
  39         ARTIM23 = 0x57,
  40         DRWTIM23 = 0x58,
  41         BRST = 0x59
  42 };
  43 
  44 /**
  45  *      cmd640_set_piomode      -       set initial PIO mode data
  46  *      @ap: ATA port
  47  *      @adev: ATA device
  48  *
  49  *      Called to do the PIO mode setup.
  50  */
  51 
  52 static void cmd640_set_piomode(struct ata_port *ap, struct ata_device *adev)
  53 {
  54         struct cmd640_reg *timing = ap->private_data;
  55         struct pci_dev *pdev = to_pci_dev(ap->host->dev);
  56         struct ata_timing t;
  57         const unsigned long T = 1000000 / 33;
  58         const u8 setup_data[] = { 0x40, 0x40, 0x40, 0x80, 0x00 };
  59         u8 reg;
  60         int arttim = ARTIM0 + 2 * adev->devno;
  61         struct ata_device *pair = ata_dev_pair(adev);
  62 
  63         if (ata_timing_compute(adev, adev->pio_mode, &t, T, 0) < 0) {
  64                 printk(KERN_ERR DRV_NAME ": mode computation failed.\n");
  65                 return;
  66         }
  67 
  68         /* The second channel has shared timings and the setup timing is
  69            messy to switch to merge it for worst case */
  70         if (ap->port_no && pair) {
  71                 struct ata_timing p;
  72                 ata_timing_compute(pair, pair->pio_mode, &p, T, 1);
  73                 ata_timing_merge(&p, &t, &t, ATA_TIMING_SETUP);
  74         }
  75 
  76         /* Make the timings fit */
  77         if (t.recover > 16) {
  78                 t.active += t.recover - 16;
  79                 t.recover = 16;
  80         }
  81         if (t.active > 16)
  82                 t.active = 16;
  83 
  84         /* Now convert the clocks into values we can actually stuff into
  85            the chip */
  86 
  87         if (t.recover > 1)
  88                 t.recover--;    /* 640B only */
  89         else
  90                 t.recover = 15;
  91 
  92         if (t.setup > 4)
  93                 t.setup = 0xC0;
  94         else
  95                 t.setup = setup_data[t.setup];
  96 
  97         if (ap->port_no == 0) {
  98                 t.active &= 0x0F;       /* 0 = 16 */
  99 
 100                 /* Load setup timing */
 101                 pci_read_config_byte(pdev, arttim, &reg);
 102                 reg &= 0x3F;
 103                 reg |= t.setup;
 104                 pci_write_config_byte(pdev, arttim, reg);
 105 
 106                 /* Load active/recovery */
 107                 pci_write_config_byte(pdev, arttim + 1, (t.active << 4) | t.recover);
 108         } else {
 109                 /* Save the shared timings for channel, they will be loaded
 110                    by qc_issue. Reloading the setup time is expensive so we
 111                    keep a merged one loaded */
 112                 pci_read_config_byte(pdev, ARTIM23, &reg);
 113                 reg &= 0x3F;
 114                 reg |= t.setup;
 115                 pci_write_config_byte(pdev, ARTIM23, reg);
 116                 timing->reg58[adev->devno] = (t.active << 4) | t.recover;
 117         }
 118 }
 119 
 120 
 121 /**
 122  *      cmd640_qc_issue -       command preparation hook
 123  *      @qc: Command to be issued
 124  *
 125  *      Channel 1 has shared timings. We must reprogram the
 126  *      clock each drive 2/3 switch we do.
 127  */
 128 
 129 static unsigned int cmd640_qc_issue(struct ata_queued_cmd *qc)
 130 {
 131         struct ata_port *ap = qc->ap;
 132         struct ata_device *adev = qc->dev;
 133         struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 134         struct cmd640_reg *timing = ap->private_data;
 135 
 136         if (ap->port_no != 0 && adev->devno != timing->last) {
 137                 pci_write_config_byte(pdev, DRWTIM23, timing->reg58[adev->devno]);
 138                 timing->last = adev->devno;
 139         }
 140         return ata_sff_qc_issue(qc);
 141 }
 142 
 143 /**
 144  *      cmd640_port_start       -       port setup
 145  *      @ap: ATA port being set up
 146  *
 147  *      The CMD640 needs to maintain private data structures so we
 148  *      allocate space here.
 149  */
 150 
 151 static int cmd640_port_start(struct ata_port *ap)
 152 {
 153         struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 154         struct cmd640_reg *timing;
 155 
 156         timing = devm_kzalloc(&pdev->dev, sizeof(struct cmd640_reg), GFP_KERNEL);
 157         if (timing == NULL)
 158                 return -ENOMEM;
 159         timing->last = -1;      /* Force a load */
 160         ap->private_data = timing;
 161         return 0;
 162 }
 163 
 164 static bool cmd640_sff_irq_check(struct ata_port *ap)
 165 {
 166         struct pci_dev *pdev    = to_pci_dev(ap->host->dev);
 167         int irq_reg             = ap->port_no ? ARTIM23 : CFR;
 168         u8  irq_stat, irq_mask  = ap->port_no ? 0x10 : 0x04;
 169 
 170         pci_read_config_byte(pdev, irq_reg, &irq_stat);
 171 
 172         return irq_stat & irq_mask;
 173 }
 174 
 175 static struct scsi_host_template cmd640_sht = {
 176         ATA_PIO_SHT(DRV_NAME),
 177 };
 178 
 179 static struct ata_port_operations cmd640_port_ops = {
 180         .inherits       = &ata_sff_port_ops,
 181         /* In theory xfer_noirq is not needed once we kill the prefetcher */
 182         .sff_data_xfer  = ata_sff_data_xfer32,
 183         .sff_irq_check  = cmd640_sff_irq_check,
 184         .qc_issue       = cmd640_qc_issue,
 185         .cable_detect   = ata_cable_40wire,
 186         .set_piomode    = cmd640_set_piomode,
 187         .port_start     = cmd640_port_start,
 188 };
 189 
 190 static void cmd640_hardware_init(struct pci_dev *pdev)
 191 {
 192         u8 ctrl;
 193 
 194         /* CMD640 detected, commiserations */
 195         pci_write_config_byte(pdev, 0x5B, 0x00);
 196         /* PIO0 command cycles */
 197         pci_write_config_byte(pdev, CMDTIM, 0);
 198         /* 512 byte bursts (sector) */
 199         pci_write_config_byte(pdev, BRST, 0x40);
 200         /*
 201          * A reporter a long time ago
 202          * Had problems with the data fifo
 203          * So don't run the risk
 204          * Of putting crap on the disk
 205          * For its better just to go slow
 206          */
 207         /* Do channel 0 */
 208         pci_read_config_byte(pdev, CNTRL, &ctrl);
 209         pci_write_config_byte(pdev, CNTRL, ctrl | 0xC0);
 210         /* Ditto for channel 1 */
 211         pci_read_config_byte(pdev, ARTIM23, &ctrl);
 212         ctrl |= 0x0C;
 213         pci_write_config_byte(pdev, ARTIM23, ctrl);
 214 }
 215 
 216 static int cmd640_init_one(struct pci_dev *pdev, const struct pci_device_id *id)
 217 {
 218         static const struct ata_port_info info = {
 219                 .flags = ATA_FLAG_SLAVE_POSS,
 220                 .pio_mask = ATA_PIO4,
 221                 .port_ops = &cmd640_port_ops
 222         };
 223         const struct ata_port_info *ppi[] = { &info, NULL };
 224         int rc;
 225 
 226         rc = pcim_enable_device(pdev);
 227         if (rc)
 228                 return rc;
 229 
 230         cmd640_hardware_init(pdev);
 231 
 232         return ata_pci_sff_init_one(pdev, ppi, &cmd640_sht, NULL, 0);
 233 }
 234 
 235 #ifdef CONFIG_PM_SLEEP
 236 static int cmd640_reinit_one(struct pci_dev *pdev)
 237 {
 238         struct ata_host *host = pci_get_drvdata(pdev);
 239         int rc;
 240 
 241         rc = ata_pci_device_do_resume(pdev);
 242         if (rc)
 243                 return rc;
 244         cmd640_hardware_init(pdev);
 245         ata_host_resume(host);
 246         return 0;
 247 }
 248 #endif
 249 
 250 static const struct pci_device_id cmd640[] = {
 251         { PCI_VDEVICE(CMD, 0x640), 0 },
 252         { },
 253 };
 254 
 255 static struct pci_driver cmd640_pci_driver = {
 256         .name           = DRV_NAME,
 257         .id_table       = cmd640,
 258         .probe          = cmd640_init_one,
 259         .remove         = ata_pci_remove_one,
 260 #ifdef CONFIG_PM_SLEEP
 261         .suspend        = ata_pci_device_suspend,
 262         .resume         = cmd640_reinit_one,
 263 #endif
 264 };
 265 
 266 module_pci_driver(cmd640_pci_driver);
 267 
 268 MODULE_AUTHOR("Alan Cox");
 269 MODULE_DESCRIPTION("low-level driver for CMD640 PATA controllers");
 270 MODULE_LICENSE("GPL");
 271 MODULE_DEVICE_TABLE(pci, cmd640);
 272 MODULE_VERSION(DRV_VERSION);