xref: /linux/drivers/ata/ahci_da850.c (revision c0c914eca7f251c70facc37dfebeaf176601918d)
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");
121