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Diffstat (limited to 'drivers/clk/clk-ar9344.c')
-rw-r--r--drivers/clk/clk-ar9344.c148
1 files changed, 148 insertions, 0 deletions
diff --git a/drivers/clk/clk-ar9344.c b/drivers/clk/clk-ar9344.c
new file mode 100644
index 0000000000..c3c49fb109
--- /dev/null
+++ b/drivers/clk/clk-ar9344.c
@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2017 Oleksij Rempel <linux@rempel-privat.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+
+#include <common.h>
+#include <init.h>
+#include <io.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/err.h>
+
+#include <mach/ath79.h>
+#include <dt-bindings/clock/ath79-clk.h>
+
+#define AR9344_CPU_PLL_CONFIG 0x00
+#define AR9344_DDR_PLL_CONFIG 0x04
+#define AR9344_OUTDIV_M 0x3
+#define AR9344_OUTDIV_S 19
+#define AR9344_REFDIV_M 0x1f
+#define AR9344_REFDIV_S 12
+#define AR9344_NINT_M 0x3f
+#define AR9344_NINT_S 6
+#define AR9344_NFRAC_M 0x3f
+#define AR9344_NFRAC_S 0
+
+
+#define AR9344_CPU_DDR_CLOCK_CONTROL 0x08
+#define AR9344_CPU_FROM_CPUPLL BIT(20)
+#define AR9344_CPU_PLL_BYPASS BIT(2)
+#define AR9344_CPU_POST_DIV_M 0x1f
+#define AR9344_CPU_POST_DIV_S 5
+
+static struct clk *clks[ATH79_CLK_END];
+static struct clk_onecell_data clk_data;
+
+struct clk_ar9344 {
+ struct clk clk;
+ void __iomem *base;
+ u32 div_shift;
+ u32 div_mask;
+ const char *parent;
+};
+
+static unsigned long clk_ar9344_recalc_rate(struct clk *clk,
+ unsigned long parent_rate)
+{
+ struct clk_ar9344 *f = container_of(clk, struct clk_ar9344, clk);
+ int outdiv, refdiv, nint, nfrac;
+ int cpu_post_div;
+ u32 clock_ctrl;
+ u32 val;
+
+ clock_ctrl = __raw_readl(f->base + AR9344_CPU_DDR_CLOCK_CONTROL);
+ cpu_post_div = ((clock_ctrl >> AR9344_CPU_POST_DIV_S)
+ & AR9344_CPU_POST_DIV_M) + 1;
+ if (clock_ctrl & AR9344_CPU_PLL_BYPASS) {
+ return parent_rate;
+ } else if (clock_ctrl & AR9344_CPU_FROM_CPUPLL) {
+ val = __raw_readl(f->base + AR9344_CPU_PLL_CONFIG);
+ } else {
+ val = __raw_readl(f->base + AR9344_DDR_PLL_CONFIG);
+ }
+
+ outdiv = (val >> AR9344_OUTDIV_S) & AR9344_OUTDIV_M;
+ refdiv = (val >> AR9344_REFDIV_S) & AR9344_REFDIV_M;
+ nint = (val >> AR9344_NINT_S) & AR9344_NINT_M;
+ nfrac = (val >> AR9344_NFRAC_S) & AR9344_NFRAC_M;
+
+ return (parent_rate * (nint + (nfrac >> 9))) / (refdiv * (1 << outdiv));
+}
+
+struct clk_ops clk_ar9344_ops = {
+ .recalc_rate = clk_ar9344_recalc_rate,
+};
+
+static struct clk *clk_ar9344(const char *name, const char *parent,
+ void __iomem *base)
+{
+ struct clk_ar9344 *f = xzalloc(sizeof(*f));
+
+ f->parent = parent;
+ f->base = base;
+ f->div_shift = 0;
+ f->div_mask = 0;
+
+ f->clk.ops = &clk_ar9344_ops;
+ f->clk.name = name;
+ f->clk.parent_names = &f->parent;
+ f->clk.num_parents = 1;
+
+ clk_register(&f->clk);
+
+ return &f->clk;
+}
+
+static void ar9344_pll_init(void __iomem *base)
+{
+ clks[ATH79_CLK_CPU] = clk_ar9344("cpu", "ref", base);
+}
+
+static int ar9344_clk_probe(struct device_d *dev)
+{
+ struct resource *iores;
+ void __iomem *base;
+
+ iores = dev_request_mem_resource(dev, 0);
+ if (IS_ERR(iores))
+ return PTR_ERR(iores);
+ base = IOMEM(iores->start);
+
+ ar9344_pll_init(base);
+
+ clk_data.clks = clks;
+ clk_data.clk_num = ARRAY_SIZE(clks);
+ of_clk_add_provider(dev->device_node, of_clk_src_onecell_get,
+ &clk_data);
+
+ return 0;
+}
+
+static __maybe_unused struct of_device_id ar9344_clk_dt_ids[] = {
+ {
+ .compatible = "qca,ar9344-pll",
+ }, {
+ /* sentinel */
+ }
+};
+
+static struct driver_d ar9344_clk_driver = {
+ .probe = ar9344_clk_probe,
+ .name = "ar9344_clk",
+ .of_compatible = DRV_OF_COMPAT(ar9344_clk_dt_ids),
+};
+
+static int ar9344_clk_init(void)
+{
+ return platform_driver_register(&ar9344_clk_driver);
+}
+postcore_initcall(ar9344_clk_init);