linux/drivers/ata/pata_bk3710.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0
   2
   3/*
   4 * Palmchip BK3710 PATA controller driver
   5 *
   6 * Copyright (c) 2017 Samsung Electronics Co., Ltd.
   7 *              http://www.samsung.com
   8 *
   9 * Based on palm_bk3710.c:
  10 *
  11 * Copyright (C) 2006 Texas Instruments.
  12 * Copyright (C) 2007 MontaVista Software, Inc., <source@mvista.com>
  13 */
  14
  15#include <linux/ata.h>
  16#include <linux/clk.h>
  17#include <linux/delay.h>
  18#include <linux/init.h>
  19#include <linux/ioport.h>
  20#include <linux/kernel.h>
  21#include <linux/libata.h>
  22#include <linux/module.h>
  23#include <linux/platform_device.h>
  24#include <linux/types.h>
  25
  26#define DRV_NAME "pata_bk3710"
  27
  28#define BK3710_TF_OFFSET        0x1F0
  29#define BK3710_CTL_OFFSET       0x3F6
  30
  31#define BK3710_BMISP            0x02
  32#define BK3710_IDETIMP          0x40
  33#define BK3710_UDMACTL          0x48
  34#define BK3710_MISCCTL          0x50
  35#define BK3710_REGSTB           0x54
  36#define BK3710_REGRCVR          0x58
  37#define BK3710_DATSTB           0x5C
  38#define BK3710_DATRCVR          0x60
  39#define BK3710_DMASTB           0x64
  40#define BK3710_DMARCVR          0x68
  41#define BK3710_UDMASTB          0x6C
  42#define BK3710_UDMATRP          0x70
  43#define BK3710_UDMAENV          0x74
  44#define BK3710_IORDYTMP         0x78
  45
  46static struct scsi_host_template pata_bk3710_sht = {
  47        ATA_BMDMA_SHT(DRV_NAME),
  48};
  49
  50static unsigned int ideclk_period; /* in nanoseconds */
  51
  52struct pata_bk3710_udmatiming {
  53        unsigned int rptime;    /* tRP -- Ready to pause time (nsec) */
  54        unsigned int cycletime; /* tCYCTYP2/2 -- avg Cycle Time (nsec) */
  55                                /* tENV is always a minimum of 20 nsec */
  56};
  57
  58static const struct pata_bk3710_udmatiming pata_bk3710_udmatimings[6] = {
  59        { 160, 240 / 2 },       /* UDMA Mode 0 */
  60        { 125, 160 / 2 },       /* UDMA Mode 1 */
  61        { 100, 120 / 2 },       /* UDMA Mode 2 */
  62        { 100,  90 / 2 },       /* UDMA Mode 3 */
  63        { 100,  60 / 2 },       /* UDMA Mode 4 */
  64        {  85,  40 / 2 },       /* UDMA Mode 5 */
  65};
  66
  67static void pata_bk3710_setudmamode(void __iomem *base, unsigned int dev,
  68                                    unsigned int mode)
  69{
  70        u32 val32;
  71        u16 val16;
  72        u8 tenv, trp, t0;
  73
  74        /* DMA Data Setup */
  75        t0 = DIV_ROUND_UP(pata_bk3710_udmatimings[mode].cycletime,
  76                          ideclk_period) - 1;
  77        tenv = DIV_ROUND_UP(20, ideclk_period) - 1;
  78        trp = DIV_ROUND_UP(pata_bk3710_udmatimings[mode].rptime,
  79                           ideclk_period) - 1;
  80
  81        /* udmastb Ultra DMA Access Strobe Width */
  82        val32 = ioread32(base + BK3710_UDMASTB) & (0xFF << (dev ? 0 : 8));
  83        val32 |= t0 << (dev ? 8 : 0);
  84        iowrite32(val32, base + BK3710_UDMASTB);
  85
  86        /* udmatrp Ultra DMA Ready to Pause Time */
  87        val32 = ioread32(base + BK3710_UDMATRP) & (0xFF << (dev ? 0 : 8));
  88        val32 |= trp << (dev ? 8 : 0);
  89        iowrite32(val32, base + BK3710_UDMATRP);
  90
  91        /* udmaenv Ultra DMA envelop Time */
  92        val32 = ioread32(base + BK3710_UDMAENV) & (0xFF << (dev ? 0 : 8));
  93        val32 |= tenv << (dev ? 8 : 0);
  94        iowrite32(val32, base + BK3710_UDMAENV);
  95
  96        /* Enable UDMA for Device */
  97        val16 = ioread16(base + BK3710_UDMACTL) | (1 << dev);
  98        iowrite16(val16, base + BK3710_UDMACTL);
  99}
 100
 101static void pata_bk3710_setmwdmamode(void __iomem *base, unsigned int dev,
 102                                     unsigned short min_cycle,
 103                                     unsigned int mode)
 104{
 105        const struct ata_timing *t;
 106        int cycletime;
 107        u32 val32;
 108        u16 val16;
 109        u8 td, tkw, t0;
 110
 111        t = ata_timing_find_mode(mode);
 112        cycletime = max_t(int, t->cycle, min_cycle);
 113
 114        /* DMA Data Setup */
 115        t0 = DIV_ROUND_UP(cycletime, ideclk_period);
 116        td = DIV_ROUND_UP(t->active, ideclk_period);
 117        tkw = t0 - td - 1;
 118        td--;
 119
 120        val32 = ioread32(base + BK3710_DMASTB) & (0xFF << (dev ? 0 : 8));
 121        val32 |= td << (dev ? 8 : 0);
 122        iowrite32(val32, base + BK3710_DMASTB);
 123
 124        val32 = ioread32(base + BK3710_DMARCVR) & (0xFF << (dev ? 0 : 8));
 125        val32 |= tkw << (dev ? 8 : 0);
 126        iowrite32(val32, base + BK3710_DMARCVR);
 127
 128        /* Disable UDMA for Device */
 129        val16 = ioread16(base + BK3710_UDMACTL) & ~(1 << dev);
 130        iowrite16(val16, base + BK3710_UDMACTL);
 131}
 132
 133static void pata_bk3710_set_dmamode(struct ata_port *ap,
 134                                    struct ata_device *adev)
 135{
 136        void __iomem *base = (void __iomem *)ap->ioaddr.bmdma_addr;
 137        int is_slave = adev->devno;
 138        const u8 xferspeed = adev->dma_mode;
 139
 140        if (xferspeed >= XFER_UDMA_0)
 141                pata_bk3710_setudmamode(base, is_slave,
 142                                        xferspeed - XFER_UDMA_0);
 143        else
 144                pata_bk3710_setmwdmamode(base, is_slave,
 145                                         adev->id[ATA_ID_EIDE_DMA_MIN],
 146                                         xferspeed);
 147}
 148
 149static void pata_bk3710_setpiomode(void __iomem *base, struct ata_device *pair,
 150                                   unsigned int dev, unsigned int cycletime,
 151                                   unsigned int mode)
 152{
 153        const struct ata_timing *t;
 154        u32 val32;
 155        u8 t2, t2i, t0;
 156
 157        t = ata_timing_find_mode(XFER_PIO_0 + mode);
 158
 159        /* PIO Data Setup */
 160        t0 = DIV_ROUND_UP(cycletime, ideclk_period);
 161        t2 = DIV_ROUND_UP(t->active, ideclk_period);
 162
 163        t2i = t0 - t2 - 1;
 164        t2--;
 165
 166        val32 = ioread32(base + BK3710_DATSTB) & (0xFF << (dev ? 0 : 8));
 167        val32 |= t2 << (dev ? 8 : 0);
 168        iowrite32(val32, base + BK3710_DATSTB);
 169
 170        val32 = ioread32(base + BK3710_DATRCVR) & (0xFF << (dev ? 0 : 8));
 171        val32 |= t2i << (dev ? 8 : 0);
 172        iowrite32(val32, base + BK3710_DATRCVR);
 173
 174        /* FIXME: this is broken also in the old driver */
 175        if (pair) {
 176                u8 mode2 = pair->pio_mode - XFER_PIO_0;
 177
 178                if (mode2 < mode)
 179                        mode = mode2;
 180        }
 181
 182        /* TASKFILE Setup */
 183        t0 = DIV_ROUND_UP(t->cyc8b, ideclk_period);
 184        t2 = DIV_ROUND_UP(t->act8b, ideclk_period);
 185
 186        t2i = t0 - t2 - 1;
 187        t2--;
 188
 189        val32 = ioread32(base + BK3710_REGSTB) & (0xFF << (dev ? 0 : 8));
 190        val32 |= t2 << (dev ? 8 : 0);
 191        iowrite32(val32, base + BK3710_REGSTB);
 192
 193        val32 = ioread32(base + BK3710_REGRCVR) & (0xFF << (dev ? 0 : 8));
 194        val32 |= t2i << (dev ? 8 : 0);
 195        iowrite32(val32, base + BK3710_REGRCVR);
 196}
 197
 198static void pata_bk3710_set_piomode(struct ata_port *ap,
 199                                    struct ata_device *adev)
 200{
 201        void __iomem *base = (void __iomem *)ap->ioaddr.bmdma_addr;
 202        struct ata_device *pair = ata_dev_pair(adev);
 203        const struct ata_timing *t = ata_timing_find_mode(adev->pio_mode);
 204        const u16 *id = adev->id;
 205        unsigned int cycle_time = 0;
 206        int is_slave = adev->devno;
 207        const u8 pio = adev->pio_mode - XFER_PIO_0;
 208
 209        if (id[ATA_ID_FIELD_VALID] & 2) {
 210                if (ata_id_has_iordy(id))
 211                        cycle_time = id[ATA_ID_EIDE_PIO_IORDY];
 212                else
 213                        cycle_time = id[ATA_ID_EIDE_PIO];
 214
 215                /* conservative "downgrade" for all pre-ATA2 drives */
 216                if (pio < 3 && cycle_time < t->cycle)
 217                        cycle_time = 0; /* use standard timing */
 218        }
 219
 220        if (!cycle_time)
 221                cycle_time = t->cycle;
 222
 223        pata_bk3710_setpiomode(base, pair, is_slave, cycle_time, pio);
 224}
 225
 226static void pata_bk3710_chipinit(void __iomem *base)
 227{
 228        /*
 229         * REVISIT:  the ATA reset signal needs to be managed through a
 230         * GPIO, which means it should come from platform_data.  Until
 231         * we get and use such information, we have to trust that things
 232         * have been reset before we get here.
 233         */
 234
 235        /*
 236         * Program the IDETIMP Register Value based on the following assumptions
 237         *
 238         * (ATA_IDETIMP_IDEEN           , ENABLE ) |
 239         * (ATA_IDETIMP_PREPOST1        , DISABLE) |
 240         * (ATA_IDETIMP_PREPOST0        , DISABLE) |
 241         *
 242         * DM6446 silicon rev 2.1 and earlier have no observed net benefit
 243         * from enabling prefetch/postwrite.
 244         */
 245        iowrite16(BIT(15), base + BK3710_IDETIMP);
 246
 247        /*
 248         * UDMACTL Ultra-ATA DMA Control
 249         * (ATA_UDMACTL_UDMAP1  , 0 ) |
 250         * (ATA_UDMACTL_UDMAP0  , 0 )
 251         *
 252         */
 253        iowrite16(0, base + BK3710_UDMACTL);
 254
 255        /*
 256         * MISCCTL Miscellaneous Conrol Register
 257         * (ATA_MISCCTL_HWNHLD1P        , 1 cycle)
 258         * (ATA_MISCCTL_HWNHLD0P        , 1 cycle)
 259         * (ATA_MISCCTL_TIMORIDE        , 1)
 260         */
 261        iowrite32(0x001, base + BK3710_MISCCTL);
 262
 263        /*
 264         * IORDYTMP IORDY Timer for Primary Register
 265         * (ATA_IORDYTMP_IORDYTMP       , DISABLE)
 266         */
 267        iowrite32(0, base + BK3710_IORDYTMP);
 268
 269        /*
 270         * Configure BMISP Register
 271         * (ATA_BMISP_DMAEN1    , DISABLE )     |
 272         * (ATA_BMISP_DMAEN0    , DISABLE )     |
 273         * (ATA_BMISP_IORDYINT  , CLEAR)        |
 274         * (ATA_BMISP_INTRSTAT  , CLEAR)        |
 275         * (ATA_BMISP_DMAERROR  , CLEAR)
 276         */
 277        iowrite16(0xE, base + BK3710_BMISP);
 278
 279        pata_bk3710_setpiomode(base, NULL, 0, 600, 0);
 280        pata_bk3710_setpiomode(base, NULL, 1, 600, 0);
 281}
 282
 283static struct ata_port_operations pata_bk3710_ports_ops = {
 284        .inherits               = &ata_bmdma_port_ops,
 285        .cable_detect           = ata_cable_80wire,
 286
 287        .set_piomode            = pata_bk3710_set_piomode,
 288        .set_dmamode            = pata_bk3710_set_dmamode,
 289};
 290
 291static int __init pata_bk3710_probe(struct platform_device *pdev)
 292{
 293        struct clk *clk;
 294        struct resource *mem;
 295        struct ata_host *host;
 296        struct ata_port *ap;
 297        void __iomem *base;
 298        unsigned long rate;
 299        int irq;
 300
 301        clk = devm_clk_get(&pdev->dev, NULL);
 302        if (IS_ERR(clk))
 303                return -ENODEV;
 304
 305        clk_enable(clk);
 306        rate = clk_get_rate(clk);
 307        if (!rate)
 308                return -EINVAL;
 309
 310        /* NOTE:  round *down* to meet minimum timings; we count in clocks */
 311        ideclk_period = 1000000000UL / rate;
 312
 313        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 314
 315        irq = platform_get_irq(pdev, 0);
 316        if (irq < 0) {
 317                pr_err(DRV_NAME ": failed to get IRQ resource\n");
 318                return irq;
 319        }
 320
 321        base = devm_ioremap_resource(&pdev->dev, mem);
 322        if (IS_ERR(base))
 323                return PTR_ERR(base);
 324
 325        /* configure the Palmchip controller */
 326        pata_bk3710_chipinit(base);
 327
 328        /* allocate host */
 329        host = ata_host_alloc(&pdev->dev, 1);
 330        if (!host)
 331                return -ENOMEM;
 332        ap = host->ports[0];
 333
 334        ap->ops = &pata_bk3710_ports_ops;
 335        ap->pio_mask = ATA_PIO4;
 336        ap->mwdma_mask = ATA_MWDMA2;
 337        ap->udma_mask = rate < 100000000 ? ATA_UDMA4 : ATA_UDMA5;
 338        ap->flags |= ATA_FLAG_SLAVE_POSS;
 339
 340        ap->ioaddr.data_addr            = base + BK3710_TF_OFFSET;
 341        ap->ioaddr.error_addr           = base + BK3710_TF_OFFSET + 1;
 342        ap->ioaddr.feature_addr         = base + BK3710_TF_OFFSET + 1;
 343        ap->ioaddr.nsect_addr           = base + BK3710_TF_OFFSET + 2;
 344        ap->ioaddr.lbal_addr            = base + BK3710_TF_OFFSET + 3;
 345        ap->ioaddr.lbam_addr            = base + BK3710_TF_OFFSET + 4;
 346        ap->ioaddr.lbah_addr            = base + BK3710_TF_OFFSET + 5;
 347        ap->ioaddr.device_addr          = base + BK3710_TF_OFFSET + 6;
 348        ap->ioaddr.status_addr          = base + BK3710_TF_OFFSET + 7;
 349        ap->ioaddr.command_addr         = base + BK3710_TF_OFFSET + 7;
 350
 351        ap->ioaddr.altstatus_addr       = base + BK3710_CTL_OFFSET;
 352        ap->ioaddr.ctl_addr             = base + BK3710_CTL_OFFSET;
 353
 354        ap->ioaddr.bmdma_addr           = base;
 355
 356        ata_port_desc(ap, "cmd 0x%lx ctl 0x%lx",
 357                      (unsigned long)base + BK3710_TF_OFFSET,
 358                      (unsigned long)base + BK3710_CTL_OFFSET);
 359
 360        /* activate */
 361        return ata_host_activate(host, irq, ata_sff_interrupt, 0,
 362                                 &pata_bk3710_sht);
 363}
 364
 365/* work with hotplug and coldplug */
 366MODULE_ALIAS("platform:palm_bk3710");
 367
 368static struct platform_driver pata_bk3710_driver = {
 369        .driver = {
 370                .name = "palm_bk3710",
 371        },
 372};
 373
 374static int __init pata_bk3710_init(void)
 375{
 376        return platform_driver_probe(&pata_bk3710_driver, pata_bk3710_probe);
 377}
 378
 379module_init(pata_bk3710_init);
 380MODULE_LICENSE("GPL v2");
 381