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-rw-r--r--drivers/clk/sunxi/clk-sun9i-core.c282
1 files changed, 282 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 000000000..d93c7a53c
--- /dev/null
+++ b/drivers/clk/sunxi/clk-sun9i-core.c
@@ -0,0 +1,282 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2014 Chen-Yu Tsai
+ *
+ * Chen-Yu Tsai <wens@csie.org>
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.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 PLL4
+ * 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(struct factors_request *req)
+{
+ int n;
+ int m = 1;
+ int p = 1;
+
+ /* Normalize value to a 6 MHz multiple (24 MHz / 4) */
+ n = DIV_ROUND_UP(req->rate, 6000000);
+
+ /* If n is too large switch to steps of 12 MHz */
+ if (n > 255) {
+ m = 0;
+ n = (n + 1) / 2;
+ }
+
+ /* If n is still too large switch to steps of 24 MHz */
+ if (n > 255) {
+ p = 0;
+ n = (n + 1) / 2;
+ }
+
+ /* n must be between 12 and 255 */
+ if (n > 255)
+ n = 255;
+ else if (n < 12)
+ n = 12;
+
+ req->rate = ((24000000 * n) >> p) / (m + 1);
+ req->n = n;
+ req->m = m;
+ req->p = p;
+}
+
+static const 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)
+{
+ void __iomem *reg;
+
+ reg = of_io_request_and_map(node, 0, of_node_full_name(node));
+ if (IS_ERR(reg)) {
+ pr_err("Could not get registers for a80-pll4-clk: %pOFn\n",
+ node);
+ return;
+ }
+
+ sunxi_factors_register(node, &sun9i_a80_pll4_data,
+ &sun9i_a80_pll4_lock, reg);
+}
+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(struct factors_request *req)
+{
+ u32 div;
+
+ if (req->parent_rate < req->rate)
+ req->rate = req->parent_rate;
+
+ div = DIV_ROUND_UP(req->parent_rate, req->rate);
+
+ /* maximum divider is 4 */
+ if (div > 4)
+ div = 4;
+
+ req->rate = req->parent_rate / div;
+ req->m = div;
+}
+
+static const 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)
+{
+ void __iomem *reg;
+
+ reg = of_io_request_and_map(node, 0, of_node_full_name(node));
+ if (IS_ERR(reg)) {
+ pr_err("Could not get registers for a80-gt-clk: %pOFn\n",
+ node);
+ return;
+ }
+
+ /* The GT bus clock needs to be always enabled */
+ sunxi_factors_register_critical(node, &sun9i_a80_gt_data,
+ &sun9i_a80_gt_lock, reg);
+}
+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(struct factors_request *req)
+{
+ u32 _p;
+
+ if (req->parent_rate < req->rate)
+ req->rate = req->parent_rate;
+
+ _p = order_base_2(DIV_ROUND_UP(req->parent_rate, req->rate));
+
+ /* maximum p is 3 */
+ if (_p > 3)
+ _p = 3;
+
+ req->rate = req->parent_rate >> _p;
+ req->p = _p;
+}
+
+static const 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)
+{
+ void __iomem *reg;
+
+ reg = of_io_request_and_map(node, 0, of_node_full_name(node));
+ if (IS_ERR(reg)) {
+ pr_err("Could not get registers for a80-ahb-clk: %pOFn\n",
+ node);
+ return;
+ }
+
+ sunxi_factors_register(node, &sun9i_a80_ahb_data,
+ &sun9i_a80_ahb_lock, reg);
+}
+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)
+{
+ void __iomem *reg;
+
+ reg = of_io_request_and_map(node, 0, of_node_full_name(node));
+ if (IS_ERR(reg)) {
+ pr_err("Could not get registers for a80-apb0-clk: %pOFn\n",
+ node);
+ return;
+ }
+
+ sunxi_factors_register(node, &sun9i_a80_apb0_data,
+ &sun9i_a80_apb0_lock, reg);
+}
+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(struct factors_request *req)
+{
+ u32 div;
+
+ if (req->parent_rate < req->rate)
+ req->rate = req->parent_rate;
+
+ div = DIV_ROUND_UP(req->parent_rate, req->rate);
+
+ /* Highest possible divider is 256 (p = 3, m = 31) */
+ if (div > 256)
+ div = 256;
+
+ req->p = order_base_2(div);
+ req->m = (req->parent_rate >> req->p) - 1;
+ req->rate = (req->parent_rate >> req->p) / (req->m + 1);
+}
+
+static const 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)
+{
+ void __iomem *reg;
+
+ reg = of_io_request_and_map(node, 0, of_node_full_name(node));
+ if (IS_ERR(reg)) {
+ pr_err("Could not get registers for a80-apb1-clk: %pOFn\n",
+ node);
+ return;
+ }
+
+ sunxi_factors_register(node, &sun9i_a80_apb1_data,
+ &sun9i_a80_apb1_lock, reg);
+}
+CLK_OF_DECLARE(sun9i_a80_apb1, "allwinner,sun9i-a80-apb1-clk", sun9i_a80_apb1_setup);