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path: root/drivers/clk/sunxi/clk-sun9i-core.c
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-rw-r--r--drivers/clk/sunxi/clk-sun9i-core.c271
1 files changed, 271 insertions, 0 deletions
diff --git a/drivers/clk/sunxi/clk-sun9i-core.c b/drivers/clk/sunxi/clk-sun9i-core.c
new file mode 100644
index 000000000000..3cb9036d91bb
--- /dev/null
+++ b/drivers/clk/sunxi/clk-sun9i-core.c
@@ -0,0 +1,271 @@
+/*
+ * Copyright 2014 Chen-Yu Tsai
+ *
+ * Chen-Yu Tsai <wens@csie.org>
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/log2.h>
+
+#include "clk-factors.h"
+
+
+/**
+ * sun9i_a80_get_pll4_factors() - calculates n, p, m factors for PLL1
+ * PLL4 rate is calculated as follows
+ * rate = (parent_rate * n >> p) / (m + 1);
+ * parent_rate is always 24Mhz
+ *
+ * p and m are named div1 and div2 in Allwinner's SDK
+ */
+
+static void sun9i_a80_get_pll4_factors(u32 *freq, u32 parent_rate,
+ u8 *n, u8 *k, u8 *m, u8 *p)
+{
+ int div;
+
+ /* Normalize value to a 6M multiple */
+ div = DIV_ROUND_UP(*freq, 6000000);
+
+ /* divs above 256 cannot be odd */
+ if (div > 256)
+ div = round_up(div, 2);
+
+ /* divs above 512 must be a multiple of 4 */
+ if (div > 512)
+ div = round_up(div, 4);
+
+ *freq = 6000000 * div;
+
+ /* we were called to round the frequency, we can now return */
+ if (n == NULL)
+ return;
+
+ /* p will be 1 for divs under 512 */
+ if (div < 512)
+ *p = 1;
+ else
+ *p = 0;
+
+ /* m will be 1 if div is odd */
+ if (div & 1)
+ *m = 1;
+ else
+ *m = 0;
+
+ /* calculate a suitable n based on m and p */
+ *n = div / (*p + 1) / (*m + 1);
+}
+
+static struct clk_factors_config sun9i_a80_pll4_config = {
+ .mshift = 18,
+ .mwidth = 1,
+ .nshift = 8,
+ .nwidth = 8,
+ .pshift = 16,
+ .pwidth = 1,
+};
+
+static const struct factors_data sun9i_a80_pll4_data __initconst = {
+ .enable = 31,
+ .table = &sun9i_a80_pll4_config,
+ .getter = sun9i_a80_get_pll4_factors,
+};
+
+static DEFINE_SPINLOCK(sun9i_a80_pll4_lock);
+
+static void __init sun9i_a80_pll4_setup(struct device_node *node)
+{
+ sunxi_factors_register(node, &sun9i_a80_pll4_data, &sun9i_a80_pll4_lock);
+}
+CLK_OF_DECLARE(sun9i_a80_pll4, "allwinner,sun9i-a80-pll4-clk", sun9i_a80_pll4_setup);
+
+
+/**
+ * sun9i_a80_get_gt_factors() - calculates m factor for GT
+ * GT rate is calculated as follows
+ * rate = parent_rate / (m + 1);
+ */
+
+static void sun9i_a80_get_gt_factors(u32 *freq, u32 parent_rate,
+ u8 *n, u8 *k, u8 *m, u8 *p)
+{
+ u32 div;
+
+ if (parent_rate < *freq)
+ *freq = parent_rate;
+
+ div = DIV_ROUND_UP(parent_rate, *freq);
+
+ /* maximum divider is 4 */
+ if (div > 4)
+ div = 4;
+
+ *freq = parent_rate / div;
+
+ /* we were called to round the frequency, we can now return */
+ if (!m)
+ return;
+
+ *m = div;
+}
+
+static struct clk_factors_config sun9i_a80_gt_config = {
+ .mshift = 0,
+ .mwidth = 2,
+};
+
+static const struct factors_data sun9i_a80_gt_data __initconst = {
+ .mux = 24,
+ .muxmask = BIT(1) | BIT(0),
+ .table = &sun9i_a80_gt_config,
+ .getter = sun9i_a80_get_gt_factors,
+};
+
+static DEFINE_SPINLOCK(sun9i_a80_gt_lock);
+
+static void __init sun9i_a80_gt_setup(struct device_node *node)
+{
+ struct clk *gt = sunxi_factors_register(node, &sun9i_a80_gt_data,
+ &sun9i_a80_gt_lock);
+
+ /* The GT bus clock needs to be always enabled */
+ __clk_get(gt);
+ clk_prepare_enable(gt);
+}
+CLK_OF_DECLARE(sun9i_a80_gt, "allwinner,sun9i-a80-gt-clk", sun9i_a80_gt_setup);
+
+
+/**
+ * sun9i_a80_get_ahb_factors() - calculates p factor for AHB0/1/2
+ * AHB rate is calculated as follows
+ * rate = parent_rate >> p;
+ */
+
+static void sun9i_a80_get_ahb_factors(u32 *freq, u32 parent_rate,
+ u8 *n, u8 *k, u8 *m, u8 *p)
+{
+ u32 _p;
+
+ if (parent_rate < *freq)
+ *freq = parent_rate;
+
+ _p = order_base_2(DIV_ROUND_UP(parent_rate, *freq));
+
+ /* maximum p is 3 */
+ if (_p > 3)
+ _p = 3;
+
+ *freq = parent_rate >> _p;
+
+ /* we were called to round the frequency, we can now return */
+ if (!p)
+ return;
+
+ *p = _p;
+}
+
+static struct clk_factors_config sun9i_a80_ahb_config = {
+ .pshift = 0,
+ .pwidth = 2,
+};
+
+static const struct factors_data sun9i_a80_ahb_data __initconst = {
+ .mux = 24,
+ .muxmask = BIT(1) | BIT(0),
+ .table = &sun9i_a80_ahb_config,
+ .getter = sun9i_a80_get_ahb_factors,
+};
+
+static DEFINE_SPINLOCK(sun9i_a80_ahb_lock);
+
+static void __init sun9i_a80_ahb_setup(struct device_node *node)
+{
+ sunxi_factors_register(node, &sun9i_a80_ahb_data, &sun9i_a80_ahb_lock);
+}
+CLK_OF_DECLARE(sun9i_a80_ahb, "allwinner,sun9i-a80-ahb-clk", sun9i_a80_ahb_setup);
+
+
+static const struct factors_data sun9i_a80_apb0_data __initconst = {
+ .mux = 24,
+ .muxmask = BIT(0),
+ .table = &sun9i_a80_ahb_config,
+ .getter = sun9i_a80_get_ahb_factors,
+};
+
+static DEFINE_SPINLOCK(sun9i_a80_apb0_lock);
+
+static void __init sun9i_a80_apb0_setup(struct device_node *node)
+{
+ sunxi_factors_register(node, &sun9i_a80_apb0_data, &sun9i_a80_apb0_lock);
+}
+CLK_OF_DECLARE(sun9i_a80_apb0, "allwinner,sun9i-a80-apb0-clk", sun9i_a80_apb0_setup);
+
+
+/**
+ * sun9i_a80_get_apb1_factors() - calculates m, p factors for APB1
+ * APB1 rate is calculated as follows
+ * rate = (parent_rate >> p) / (m + 1);
+ */
+
+static void sun9i_a80_get_apb1_factors(u32 *freq, u32 parent_rate,
+ u8 *n, u8 *k, u8 *m, u8 *p)
+{
+ u32 div;
+ u8 calcm, calcp;
+
+ if (parent_rate < *freq)
+ *freq = parent_rate;
+
+ div = DIV_ROUND_UP(parent_rate, *freq);
+
+ /* Highest possible divider is 256 (p = 3, m = 31) */
+ if (div > 256)
+ div = 256;
+
+ calcp = order_base_2(div);
+ calcm = (parent_rate >> calcp) - 1;
+ *freq = (parent_rate >> calcp) / (calcm + 1);
+
+ /* we were called to round the frequency, we can now return */
+ if (n == NULL)
+ return;
+
+ *m = calcm;
+ *p = calcp;
+}
+
+static struct clk_factors_config sun9i_a80_apb1_config = {
+ .mshift = 0,
+ .mwidth = 5,
+ .pshift = 16,
+ .pwidth = 2,
+};
+
+static const struct factors_data sun9i_a80_apb1_data __initconst = {
+ .mux = 24,
+ .muxmask = BIT(0),
+ .table = &sun9i_a80_apb1_config,
+ .getter = sun9i_a80_get_apb1_factors,
+};
+
+static DEFINE_SPINLOCK(sun9i_a80_apb1_lock);
+
+static void __init sun9i_a80_apb1_setup(struct device_node *node)
+{
+ sunxi_factors_register(node, &sun9i_a80_apb1_data, &sun9i_a80_apb1_lock);
+}
+CLK_OF_DECLARE(sun9i_a80_apb1, "allwinner,sun9i-a80-apb1-clk", sun9i_a80_apb1_setup);

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