memory: add a driver for atmel ram controllers
Atmel SoCs have one or multiple RAM controllers that need one or multiple clocks
to run.
This driver handle those clocks.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
diff --git a/drivers/memory/atmel-sdramc.c b/drivers/memory/atmel-sdramc.c
new file mode 100644
index 0000000..fed04e8
--- /dev/null
+++ b/drivers/memory/atmel-sdramc.c
@@ -0,0 +1,98 @@
+/*
+ * Atmel (Multi-port DDR-)SDRAM Controller driver
+ *
+ * Copyright (C) 2014 Atmel
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+
+struct at91_ramc_caps {
+ bool has_ddrck;
+ bool has_mpddr_clk;
+};
+
+static const struct at91_ramc_caps at91rm9200_caps = { };
+
+static const struct at91_ramc_caps at91sam9g45_caps = {
+ .has_ddrck = 1,
+ .has_mpddr_clk = 0,
+};
+
+static const struct at91_ramc_caps sama5d3_caps = {
+ .has_ddrck = 1,
+ .has_mpddr_clk = 1,
+};
+
+static const struct of_device_id atmel_ramc_of_match[] = {
+ { .compatible = "atmel,at91rm9200-sdramc", .data = &at91rm9200_caps, },
+ { .compatible = "atmel,at91sam9260-sdramc", .data = &at91rm9200_caps, },
+ { .compatible = "atmel,at91sam9g45-ddramc", .data = &at91sam9g45_caps, },
+ { .compatible = "atmel,sama5d3-ddramc", .data = &sama5d3_caps, },
+ {},
+};
+MODULE_DEVICE_TABLE(of, atmel_ramc_of_match);
+
+static int atmel_ramc_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *match;
+ const struct at91_ramc_caps *caps;
+ struct clk *clk;
+
+ match = of_match_device(atmel_ramc_of_match, &pdev->dev);
+ caps = match->data;
+
+ if (caps->has_ddrck) {
+ clk = devm_clk_get(&pdev->dev, "ddrck");
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+ clk_prepare_enable(clk);
+ }
+
+ if (caps->has_mpddr_clk) {
+ clk = devm_clk_get(&pdev->dev, "mpddr");
+ if (IS_ERR(clk)) {
+ pr_err("AT91 RAMC: couldn't get mpddr clock\n");
+ return PTR_ERR(clk);
+ }
+ clk_prepare_enable(clk);
+ }
+
+ return 0;
+}
+
+static struct platform_driver atmel_ramc_driver = {
+ .probe = atmel_ramc_probe,
+ .driver = {
+ .name = "atmel-ramc",
+ .owner = THIS_MODULE,
+ .of_match_table = atmel_ramc_of_match,
+ },
+};
+
+static int __init atmel_ramc_init(void)
+{
+ return platform_driver_register(&atmel_ramc_driver);
+}
+module_init(atmel_ramc_init);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@free-electrons.com>");
+MODULE_DESCRIPTION("Atmel (Multi-port DDR-)SDRAM Controller");