xref: /OK3568_Linux_fs/kernel/drivers/memory/atmel-sdramc.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Atmel (Multi-port DDR-)SDRAM Controller driver
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Author: Alexandre Belloni <alexandre.belloni@free-electrons.com>
6*4882a593Smuzhiyun  *
7*4882a593Smuzhiyun  * Copyright (C) 2014 Atmel
8*4882a593Smuzhiyun  */
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun #include <linux/clk.h>
11*4882a593Smuzhiyun #include <linux/err.h>
12*4882a593Smuzhiyun #include <linux/kernel.h>
13*4882a593Smuzhiyun #include <linux/init.h>
14*4882a593Smuzhiyun #include <linux/of_platform.h>
15*4882a593Smuzhiyun #include <linux/platform_device.h>
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun struct at91_ramc_caps {
18*4882a593Smuzhiyun 	bool has_ddrck;
19*4882a593Smuzhiyun 	bool has_mpddr_clk;
20*4882a593Smuzhiyun };
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun static const struct at91_ramc_caps at91rm9200_caps = { };
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun static const struct at91_ramc_caps at91sam9g45_caps = {
25*4882a593Smuzhiyun 	.has_ddrck = 1,
26*4882a593Smuzhiyun 	.has_mpddr_clk = 0,
27*4882a593Smuzhiyun };
28*4882a593Smuzhiyun 
29*4882a593Smuzhiyun static const struct at91_ramc_caps sama5d3_caps = {
30*4882a593Smuzhiyun 	.has_ddrck = 1,
31*4882a593Smuzhiyun 	.has_mpddr_clk = 1,
32*4882a593Smuzhiyun };
33*4882a593Smuzhiyun 
34*4882a593Smuzhiyun static const struct of_device_id atmel_ramc_of_match[] = {
35*4882a593Smuzhiyun 	{ .compatible = "atmel,at91rm9200-sdramc", .data = &at91rm9200_caps, },
36*4882a593Smuzhiyun 	{ .compatible = "atmel,at91sam9260-sdramc", .data = &at91rm9200_caps, },
37*4882a593Smuzhiyun 	{ .compatible = "atmel,at91sam9g45-ddramc", .data = &at91sam9g45_caps, },
38*4882a593Smuzhiyun 	{ .compatible = "atmel,sama5d3-ddramc", .data = &sama5d3_caps, },
39*4882a593Smuzhiyun 	{},
40*4882a593Smuzhiyun };
41*4882a593Smuzhiyun 
atmel_ramc_probe(struct platform_device * pdev)42*4882a593Smuzhiyun static int atmel_ramc_probe(struct platform_device *pdev)
43*4882a593Smuzhiyun {
44*4882a593Smuzhiyun 	const struct at91_ramc_caps *caps;
45*4882a593Smuzhiyun 	struct clk *clk;
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun 	caps = of_device_get_match_data(&pdev->dev);
48*4882a593Smuzhiyun 
49*4882a593Smuzhiyun 	if (caps->has_ddrck) {
50*4882a593Smuzhiyun 		clk = devm_clk_get(&pdev->dev, "ddrck");
51*4882a593Smuzhiyun 		if (IS_ERR(clk))
52*4882a593Smuzhiyun 			return PTR_ERR(clk);
53*4882a593Smuzhiyun 		clk_prepare_enable(clk);
54*4882a593Smuzhiyun 	}
55*4882a593Smuzhiyun 
56*4882a593Smuzhiyun 	if (caps->has_mpddr_clk) {
57*4882a593Smuzhiyun 		clk = devm_clk_get(&pdev->dev, "mpddr");
58*4882a593Smuzhiyun 		if (IS_ERR(clk)) {
59*4882a593Smuzhiyun 			pr_err("AT91 RAMC: couldn't get mpddr clock\n");
60*4882a593Smuzhiyun 			return PTR_ERR(clk);
61*4882a593Smuzhiyun 		}
62*4882a593Smuzhiyun 		clk_prepare_enable(clk);
63*4882a593Smuzhiyun 	}
64*4882a593Smuzhiyun 
65*4882a593Smuzhiyun 	return 0;
66*4882a593Smuzhiyun }
67*4882a593Smuzhiyun 
68*4882a593Smuzhiyun static struct platform_driver atmel_ramc_driver = {
69*4882a593Smuzhiyun 	.probe		= atmel_ramc_probe,
70*4882a593Smuzhiyun 	.driver		= {
71*4882a593Smuzhiyun 		.name	= "atmel-ramc",
72*4882a593Smuzhiyun 		.of_match_table = atmel_ramc_of_match,
73*4882a593Smuzhiyun 	},
74*4882a593Smuzhiyun };
75*4882a593Smuzhiyun 
76*4882a593Smuzhiyun builtin_platform_driver(atmel_ramc_driver);
77