drivers/memory/atmel-sdramc.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Atmel (Multi-port DDR-)SDRAM Controller driver
0004  *
0005  * Author: Alexandre Belloni <alexandre.belloni@free-electrons.com>
0006  *
0007  * Copyright (C) 2014 Atmel
0008  */
0009
0010 #include <linux/clk.h>
0011 #include <linux/err.h>
0012 #include <linux/kernel.h>
0013 #include <linux/init.h>
0014 #include <linux/of_platform.h>
0015 #include <linux/platform_device.h>
0016
0017 struct at91_ramc_caps {
0018     bool has_ddrck;
0019     bool has_mpddr_clk;
0020 };
0021
0022 static const struct at91_ramc_caps at91rm9200_caps = { };
0023
0024 static const struct at91_ramc_caps at91sam9g45_caps = {
0025     .has_ddrck = 1,
0026     .has_mpddr_clk = 0,
0027 };
0028
0029 static const struct at91_ramc_caps sama5d3_caps = {
0030     .has_ddrck = 1,
0031     .has_mpddr_clk = 1,
0032 };
0033
0034 static const struct of_device_id atmel_ramc_of_match[] = {
0035     { .compatible = "atmel,at91rm9200-sdramc", .data = &at91rm9200_caps, },
0036     { .compatible = "atmel,at91sam9260-sdramc", .data = &at91rm9200_caps, },
0037     { .compatible = "atmel,at91sam9g45-ddramc", .data = &at91sam9g45_caps, },
0038     { .compatible = "atmel,sama5d3-ddramc", .data = &sama5d3_caps, },
0039     {},
0040 };
0041
0042 static int atmel_ramc_probe(struct platform_device *pdev)
0043 {
0044     const struct at91_ramc_caps *caps;
0045     struct clk *clk;
0046
0047     caps = of_device_get_match_data(&pdev->dev);
0048
0049     if (caps->has_ddrck) {
0050         clk = devm_clk_get(&pdev->dev, "ddrck");
0051         if (IS_ERR(clk))
0052             return PTR_ERR(clk);
0053         clk_prepare_enable(clk);
0054     }
0055
0056     if (caps->has_mpddr_clk) {
0057         clk = devm_clk_get(&pdev->dev, "mpddr");
0058         if (IS_ERR(clk)) {
0059             pr_err("AT91 RAMC: couldn't get mpddr clock\n");
0060             return PTR_ERR(clk);
0061         }
0062         clk_prepare_enable(clk);
0063     }
0064
0065     return 0;
0066 }
0067
0068 static struct platform_driver atmel_ramc_driver = {
0069     .probe      = atmel_ramc_probe,
0070     .driver     = {
0071         .name   = "atmel-ramc",
0072         .of_match_table = atmel_ramc_of_match,
0073     },
0074 };
0075
0076 builtin_platform_driver(atmel_ramc_driver);