drivers/ata/ahci_da850.c

   1 /*
   2  * DaVinci DA850 AHCI SATA platform driver
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2, or (at your option)
   7  * any later version.
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/pm.h>
  13 #include <linux/device.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/libata.h>
  16 #include <linux/ahci_platform.h>
  17 #include "ahci.h"
  18
  19 #define DRV_NAME "ahci_da850"
  20
  21 /* SATA PHY Control Register offset from AHCI base */
  22 #define SATA_P0PHYCR_REG        0x178
  23
  24 #define SATA_PHY_MPY(x)         ((x) << 0)
  25 #define SATA_PHY_LOS(x)         ((x) << 6)
  26 #define SATA_PHY_RXCDR(x)       ((x) << 10)
  27 #define SATA_PHY_RXEQ(x)        ((x) << 13)
  28 #define SATA_PHY_TXSWING(x)     ((x) << 19)
  29 #define SATA_PHY_ENPLL(x)       ((x) << 31)
  30
  31 /*
  32  * The multiplier needed for 1.5GHz PLL output.
  33  *
  34  * NOTE: This is currently hardcoded to be suitable for 100MHz crystal
  35  * frequency (which is used by DA850 EVM board) and may need to be changed
  36  * if you would like to use this driver on some other board.
  37  */
  38 #define DA850_SATA_CLK_MULTIPLIER       7
  39
  40 static void da850_sata_init(struct device *dev, void __iomem *pwrdn_reg,
  41                             void __iomem *ahci_base)
  42 {
  43         unsigned int val;
  44
  45         /* Enable SATA clock receiver */
  46         val = readl(pwrdn_reg);
  47         val &= ~BIT(0);
  48         writel(val, pwrdn_reg);
  49
  50         val = SATA_PHY_MPY(DA850_SATA_CLK_MULTIPLIER + 1) | SATA_PHY_LOS(1) |
  51               SATA_PHY_RXCDR(4) | SATA_PHY_RXEQ(1) | SATA_PHY_TXSWING(3) |
  52               SATA_PHY_ENPLL(1);
  53
  54         writel(val, ahci_base + SATA_P0PHYCR_REG);
  55 }
  56
  57 static const struct ata_port_info ahci_da850_port_info = {
  58         .flags          = AHCI_FLAG_COMMON,
  59         .pio_mask       = ATA_PIO4,
  60         .udma_mask      = ATA_UDMA6,
  61         .port_ops       = &ahci_platform_ops,
  62 };
  63
  64 static struct scsi_host_template ahci_platform_sht = {
  65         AHCI_SHT(DRV_NAME),
  66 };
  67
  68 static int ahci_da850_probe(struct platform_device *pdev)
  69 {
  70         struct device *dev = &pdev->dev;
  71         struct ahci_host_priv *hpriv;
  72         struct resource *res;
  73         void __iomem *pwrdn_reg;
  74         int rc;
  75
  76         hpriv = ahci_platform_get_resources(pdev);
  77         if (IS_ERR(hpriv))
  78                 return PTR_ERR(hpriv);
  79
  80         rc = ahci_platform_enable_resources(hpriv);
  81         if (rc)
  82                 return rc;
  83
  84         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
  85         if (!res)
  86                 goto disable_resources;
  87
  88         pwrdn_reg = devm_ioremap(dev, res->start, resource_size(res));
  89         if (!pwrdn_reg)
  90                 goto disable_resources;
  91
  92         da850_sata_init(dev, pwrdn_reg, hpriv->mmio);
  93
  94         rc = ahci_platform_init_host(pdev, hpriv, &ahci_da850_port_info,
  95                                      &ahci_platform_sht);
  96         if (rc)
  97                 goto disable_resources;
  98
  99         return 0;
 100 disable_resources:
 101         ahci_platform_disable_resources(hpriv);
 102         return rc;
 103 }
 104
 105 static SIMPLE_DEV_PM_OPS(ahci_da850_pm_ops, ahci_platform_suspend,
 106                          ahci_platform_resume);
 107
 108 static struct platform_driver ahci_da850_driver = {
 109         .probe = ahci_da850_probe,
 110         .remove = ata_platform_remove_one,
 111         .driver = {
 112                 .name = DRV_NAME,
 113                 .pm = &ahci_da850_pm_ops,
 114         },
 115 };
 116 module_platform_driver(ahci_da850_driver);
 117
 118 MODULE_DESCRIPTION("DaVinci DA850 AHCI SATA platform driver");
 119 MODULE_AUTHOR("Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>");
 120 MODULE_LICENSE("GPL");