drivers/ata/pata_at91.c

   1 /*
   2  * PATA driver for AT91SAM9260 Static Memory Controller
   3  * with CompactFlash interface in True IDE mode
   4  *
   5  * Copyright (C) 2009 Matyukevich Sergey
   6  *
   7  * Based on:
   8  *      * generic platform driver by Paul Mundt: drivers/ata/pata_platform.c
   9  *      * pata_at32 driver by Kristoffer Nyborg Gregertsen
  10  *      * at91_ide driver by Stanislaw Gruszka
  11  *
  12  * This program is free software; you can redistribute it and/or modify it
  13  * under the terms of the GNU General Public License version 2
  14  * as published by the Free Software Foundation.
  15  *
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <linux/blkdev.h>
  22 #include <scsi/scsi_host.h>
  23 #include <linux/ata.h>
  24 #include <linux/clk.h>
  25 #include <linux/libata.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/ata_platform.h>
  28
  29 #include <mach/at91sam9260_matrix.h>
  30 #include <mach/at91sam9_smc.h>
  31 #include <mach/at91sam9260.h>
  32 #include <mach/board.h>
  33 #include <mach/gpio.h>
  34
  35
  36 #define DRV_NAME "pata_at91"
  37 #define DRV_VERSION "0.1"
  38
  39 #define CF_IDE_OFFSET       0x00c00000
  40 #define CF_ALT_IDE_OFFSET   0x00e00000
  41 #define CF_IDE_RES_SIZE     0x08
  42
  43 struct at91_ide_info {
  44         unsigned long mode;
  45         unsigned int cs;
  46
  47         void __iomem *ide_addr;
  48         void __iomem *alt_addr;
  49 };
  50
  51 const struct ata_timing initial_timing =
  52         {XFER_PIO_0, 70, 290, 240, 600, 165, 150, 600, 0};
  53
  54 static unsigned int calc_mck_cycles(unsigned int ns, unsigned int mck_hz)
  55 {
  56         unsigned long mul;
  57
  58     /*
  59      * cycles = x [nsec] * f [Hz] / 10^9 [ns in sec] =
  60      *     x * (f / 1_000_000_000) =
  61      *     x * ((f * 65536) / 1_000_000_000) / 65536 =
  62      *     x * (((f / 10_000) * 65536) / 100_000) / 65536 =
  63      */
  64
  65     mul = (mck_hz / 10000) << 16;
  66     mul /= 100000;
  67
  68     return (ns * mul + 65536) >> 16;    /* rounding */
  69 }
  70
  71 static void set_smc_mode(struct at91_ide_info *info)
  72 {
  73     at91_sys_write(AT91_SMC_MODE(info->cs), info->mode);
  74     return;
  75 }
  76
  77 static void set_smc_timing(struct device *dev,
  78                 struct at91_ide_info *info, const struct ata_timing *ata)
  79 {
  80         int read_cycle, write_cycle, active, recover;
  81         int nrd_setup, nrd_pulse, nrd_recover;
  82         int nwe_setup, nwe_pulse;
  83
  84         int ncs_write_setup, ncs_write_pulse;
  85         int ncs_read_setup, ncs_read_pulse;
  86
  87         unsigned int mck_hz;
  88         struct clk *mck;
  89
  90         read_cycle  = ata->cyc8b;
  91         nrd_setup   = ata->setup;
  92         nrd_pulse   = ata->act8b;
  93         nrd_recover = ata->rec8b;
  94
  95         mck = clk_get(NULL, "mck");
  96         BUG_ON(IS_ERR(mck));
  97         mck_hz = clk_get_rate(mck);
  98
  99         read_cycle  = calc_mck_cycles(read_cycle, mck_hz);
 100         nrd_setup   = calc_mck_cycles(nrd_setup, mck_hz);
 101         nrd_pulse   = calc_mck_cycles(nrd_pulse, mck_hz);
 102         nrd_recover = calc_mck_cycles(nrd_recover, mck_hz);
 103
 104         clk_put(mck);
 105
 106         active  = nrd_setup + nrd_pulse;
 107         recover = read_cycle - active;
 108
 109         /* Need at least two cycles recovery */
 110         if (recover < 2)
 111                 read_cycle = active + 2;
 112
 113         /* (CS0, CS1, DIR, OE) <= (CFCE1, CFCE2, CFRNW, NCSX) timings */
 114         ncs_read_setup = 1;
 115         ncs_read_pulse = read_cycle - 2;
 116
 117         /* Write timings same as read timings */
 118         write_cycle = read_cycle;
 119         nwe_setup = nrd_setup;
 120         nwe_pulse = nrd_pulse;
 121         ncs_write_setup = ncs_read_setup;
 122         ncs_write_pulse = ncs_read_pulse;
 123
 124         dev_dbg(dev, "ATA timings: nrd_setup = %d nrd_pulse = %d nrd_cycle = %d\n",
 125                         nrd_setup, nrd_pulse, read_cycle);
 126         dev_dbg(dev, "ATA timings: nwe_setup = %d nwe_pulse = %d nwe_cycle = %d\n",
 127                         nwe_setup, nwe_pulse, write_cycle);
 128         dev_dbg(dev, "ATA timings: ncs_read_setup = %d ncs_read_pulse = %d\n",
 129                         ncs_read_setup, ncs_read_pulse);
 130         dev_dbg(dev, "ATA timings: ncs_write_setup = %d ncs_write_pulse = %d\n",
 131                         ncs_write_setup, ncs_write_pulse);
 132
 133         at91_sys_write(AT91_SMC_SETUP(info->cs),
 134                         AT91_SMC_NWESETUP_(nwe_setup) |
 135                         AT91_SMC_NRDSETUP_(nrd_setup) |
 136                         AT91_SMC_NCS_WRSETUP_(ncs_write_setup) |
 137                         AT91_SMC_NCS_RDSETUP_(ncs_read_setup));
 138
 139         at91_sys_write(AT91_SMC_PULSE(info->cs),
 140                         AT91_SMC_NWEPULSE_(nwe_pulse) |
 141                         AT91_SMC_NRDPULSE_(nrd_pulse) |
 142                         AT91_SMC_NCS_WRPULSE_(ncs_write_pulse) |
 143                         AT91_SMC_NCS_RDPULSE_(ncs_read_pulse));
 144
 145         at91_sys_write(AT91_SMC_CYCLE(info->cs),
 146                         AT91_SMC_NWECYCLE_(write_cycle) |
 147                         AT91_SMC_NRDCYCLE_(read_cycle));
 148
 149         return;
 150 }
 151
 152 static void pata_at91_set_piomode(struct ata_port *ap, struct ata_device *adev)
 153 {
 154         struct at91_ide_info *info = ap->host->private_data;
 155         struct ata_timing timing;
 156         int ret;
 157
 158         /* Compute ATA timing and set it to SMC */
 159         ret = ata_timing_compute(adev, adev->pio_mode, &timing, 1000, 0);
 160         if (ret) {
 161                 dev_warn(ap->dev, "Failed to compute ATA timing %d, \
 162                                 set PIO_0 timing\n", ret);
 163                 set_smc_timing(ap->dev, info, &initial_timing);
 164         } else {
 165                 set_smc_timing(ap->dev, info, &timing);
 166         }
 167
 168         /* Setup SMC mode */
 169         set_smc_mode(info);
 170
 171         return;
 172 }
 173
 174 static unsigned int pata_at91_data_xfer_noirq(struct ata_device *dev,
 175                 unsigned char *buf, unsigned int buflen, int rw)
 176 {
 177         struct at91_ide_info *info = dev->link->ap->host->private_data;
 178         unsigned int consumed;
 179         unsigned long flags;
 180         unsigned int mode;
 181
 182         local_irq_save(flags);
 183         mode = at91_sys_read(AT91_SMC_MODE(info->cs));
 184
 185         /* set 16bit mode before writing data */
 186         at91_sys_write(AT91_SMC_MODE(info->cs),
 187                         (mode & ~AT91_SMC_DBW) | AT91_SMC_DBW_16);
 188
 189         consumed = ata_sff_data_xfer(dev, buf, buflen, rw);
 190
 191         /* restore 8bit mode after data is written */
 192         at91_sys_write(AT91_SMC_MODE(info->cs),
 193                         (mode & ~AT91_SMC_DBW) | AT91_SMC_DBW_8);
 194
 195         local_irq_restore(flags);
 196         return consumed;
 197 }
 198
 199 static struct scsi_host_template pata_at91_sht = {
 200         ATA_PIO_SHT(DRV_NAME),
 201 };
 202
 203 static struct ata_port_operations pata_at91_port_ops = {
 204         .inherits       = &ata_sff_port_ops,
 205
 206         .sff_data_xfer  = pata_at91_data_xfer_noirq,
 207         .set_piomode    = pata_at91_set_piomode,
 208         .cable_detect   = ata_cable_40wire,
 209         .port_start     = ATA_OP_NULL,
 210 };
 211
 212 static int __devinit pata_at91_probe(struct platform_device *pdev)
 213 {
 214         struct at91_cf_data *board = pdev->dev.platform_data;
 215         struct device *dev = &pdev->dev;
 216         struct at91_ide_info *info;
 217         struct resource *mem_res;
 218         struct ata_host *host;
 219         struct ata_port *ap;
 220         int irq_flags = 0;
 221         int irq = 0;
 222         int ret;
 223
 224         /*  get platform resources: IO/CTL memories and irq/rst pins */
 225
 226         if (pdev->num_resources != 1) {
 227                 dev_err(&pdev->dev, "invalid number of resources\n");
 228                 return -EINVAL;
 229         }
 230
 231         mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 232
 233         if (!mem_res) {
 234                 dev_err(dev, "failed to get mem resource\n");
 235                 return -EINVAL;
 236         }
 237
 238         irq = board->irq_pin;
 239
 240         /* init ata host */
 241
 242         host = ata_host_alloc(dev, 1);
 243
 244         if (!host)
 245                 return -ENOMEM;
 246
 247         ap = host->ports[0];
 248         ap->ops = &pata_at91_port_ops;
 249         ap->flags |= ATA_FLAG_SLAVE_POSS;
 250         ap->pio_mask = ATA_PIO4;
 251
 252         if (!irq) {
 253                 ap->flags |= ATA_FLAG_PIO_POLLING;
 254                 ata_port_desc(ap, "no IRQ, using PIO polling");
 255         }
 256
 257         info = kzalloc(sizeof(*info), GFP_KERNEL);
 258
 259         if (!info) {
 260                 dev_err(dev, "failed to allocate memory for private data\n");
 261                 return -ENOMEM;
 262         }
 263
 264         info->cs    = board->chipselect;
 265         info->mode  = AT91_SMC_READMODE | AT91_SMC_WRITEMODE |
 266                 AT91_SMC_EXNWMODE_READY | AT91_SMC_BAT_SELECT |
 267                 AT91_SMC_DBW_8 | AT91_SMC_TDF_(0);
 268
 269         info->ide_addr = devm_ioremap(dev,
 270                         mem_res->start + CF_IDE_OFFSET, CF_IDE_RES_SIZE);
 271
 272         if (!info->ide_addr) {
 273                 dev_err(dev, "failed to map IO base\n");
 274                 ret = -ENOMEM;
 275                 goto err_ide_ioremap;
 276         }
 277
 278         info->alt_addr = devm_ioremap(dev,
 279                         mem_res->start + CF_ALT_IDE_OFFSET, CF_IDE_RES_SIZE);
 280
 281         if (!info->alt_addr) {
 282                 dev_err(dev, "failed to map CTL base\n");
 283                 ret = -ENOMEM;
 284                 goto err_alt_ioremap;
 285         }
 286
 287         ap->ioaddr.cmd_addr = info->ide_addr;
 288         ap->ioaddr.ctl_addr = info->alt_addr + 0x06;
 289         ap->ioaddr.altstatus_addr = ap->ioaddr.ctl_addr;
 290
 291         ata_sff_std_ports(&ap->ioaddr);
 292
 293         ata_port_desc(ap, "mmio cmd 0x%llx ctl 0x%llx",
 294                         (unsigned long long)mem_res->start + CF_IDE_OFFSET,
 295                         (unsigned long long)mem_res->start + CF_ALT_IDE_OFFSET);
 296
 297         host->private_data = info;
 298
 299         return ata_host_activate(host, irq ? gpio_to_irq(irq) : 0,
 300                         irq ? ata_sff_interrupt : NULL,
 301                         irq_flags, &pata_at91_sht);
 302
 303 err_alt_ioremap:
 304         devm_iounmap(dev, info->ide_addr);
 305
 306 err_ide_ioremap:
 307         kfree(info);
 308
 309         return ret;
 310 }
 311
 312 static int __devexit pata_at91_remove(struct platform_device *pdev)
 313 {
 314         struct ata_host *host = dev_get_drvdata(&pdev->dev);
 315         struct at91_ide_info *info;
 316         struct device *dev = &pdev->dev;
 317
 318         if (!host)
 319                 return 0;
 320         info = host->private_data;
 321
 322         ata_host_detach(host);
 323
 324         if (!info)
 325                 return 0;
 326
 327         devm_iounmap(dev, info->ide_addr);
 328         devm_iounmap(dev, info->alt_addr);
 329
 330         kfree(info);
 331         return 0;
 332 }
 333
 334 static struct platform_driver pata_at91_driver = {
 335         .probe          = pata_at91_probe,
 336         .remove         = __devexit_p(pata_at91_remove),
 337         .driver         = {
 338                 .name           = DRV_NAME,
 339                 .owner          = THIS_MODULE,
 340         },
 341 };
 342
 343 static int __init pata_at91_init(void)
 344 {
 345         return platform_driver_register(&pata_at91_driver);
 346 }
 347
 348 static void __exit pata_at91_exit(void)
 349 {
 350         platform_driver_unregister(&pata_at91_driver);
 351 }
 352
 353
 354 module_init(pata_at91_init);
 355 module_exit(pata_at91_exit);
 356
 357
 358 MODULE_LICENSE("GPL");
 359 MODULE_DESCRIPTION("Driver for CF in True IDE mode on AT91SAM9260 SoC");
 360 MODULE_AUTHOR("Matyukevich Sergey");
 361 MODULE_VERSION(DRV_VERSION);
 362