clk: at91: Add clock driver

The patch is referred to at91 clock driver of Linux, to make
the clock node descriptions in DT aligned with the Linux's.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

1 files changed, 56 insertions, 0 deletions

diff --git a/drivers/clk/at91/clk-h32mx.c b/drivers/clk/at91/clk-h32mx.c
new file mode 100644
index 0000000000..1a304bab21
--- /dev/null
+++ b/drivers/clk/at91/clk-h32mx.c
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+#include <dm/util.h>
+#include <linux/io.h>
+#include <mach/at91_pmc.h>
+#include "pmc.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define H32MX_MAX_FREQ	90000000
+
+static ulong sama5d4_h32mx_clk_get_rate(struct clk *clk)
+{
+	struct pmc_platdata *plat = dev_get_platdata(clk->dev);
+	struct at91_pmc *pmc = plat->reg_base;
+	ulong rate = gd->arch.mck_rate_hz;
+
+	if (readl(&pmc->mckr) & AT91_PMC_MCKR_H32MXDIV)
+		rate /= 2;
+
+	if (rate > H32MX_MAX_FREQ)
+		dm_warn("H32MX clock is too fast\n");
+
+	return rate;
+}
+
+static struct clk_ops sama5d4_h32mx_clk_ops = {
+	.get_rate = sama5d4_h32mx_clk_get_rate,
+};
+
+static int sama5d4_h32mx_clk_probe(struct udevice *dev)
+{
+	return at91_pmc_core_probe(dev);
+}
+
+static const struct udevice_id sama5d4_h32mx_clk_match[] = {
+	{ .compatible = "atmel,sama5d4-clk-h32mx" },
+	{}
+};
+
+U_BOOT_DRIVER(sama5d4_h32mx_clk) = {
+	.name = "sama5d4-h32mx-clk",
+	.id = UCLASS_CLK,
+	.of_match = sama5d4_h32mx_clk_match,
+	.probe = sama5d4_h32mx_clk_probe,
+	.platdata_auto_alloc_size = sizeof(struct pmc_platdata),
+	.ops = &sama5d4_h32mx_clk_ops,
+};