xref: /linux/drivers/ata/ahci_da850.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
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 	if (rc)
90 		goto disable_resources;
91 
92 	return 0;
93 disable_resources:
94 	ahci_platform_disable_resources(hpriv);
95 	return rc;
96 }
97 
98 static SIMPLE_DEV_PM_OPS(ahci_da850_pm_ops, ahci_platform_suspend,
99 			 ahci_platform_resume);
100 
101 static struct platform_driver ahci_da850_driver = {
102 	.probe = ahci_da850_probe,
103 	.remove = ata_platform_remove_one,
104 	.driver = {
105 		.name = "ahci_da850",
106 		.pm = &ahci_da850_pm_ops,
107 	},
108 };
109 module_platform_driver(ahci_da850_driver);
110 
111 MODULE_DESCRIPTION("DaVinci DA850 AHCI SATA platform driver");
112 MODULE_AUTHOR("Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>");
113 MODULE_LICENSE("GPL");
114