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