summaryrefslogtreecommitdiffstats
path: root/drivers/clk/clk-zynq.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/clk/clk-zynq.c')
-rw-r--r--drivers/clk/clk-zynq.c383
1 files changed, 383 insertions, 0 deletions
diff --git a/drivers/clk/clk-zynq.c b/drivers/clk/clk-zynq.c
new file mode 100644
index 000000000000..37a30514fd66
--- /dev/null
+++ b/drivers/clk/clk-zynq.c
@@ -0,0 +1,383 @@
+/*
+ * Copyright (c) 2012 National Instruments
+ *
+ * Josh Cartwright <josh.cartwright@ni.com>
+ *
+ * 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.
+ *
+ * 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/io.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/clk-provider.h>
+
+static void __iomem *slcr_base;
+
+struct zynq_pll_clk {
+ struct clk_hw hw;
+ void __iomem *pll_ctrl;
+ void __iomem *pll_cfg;
+};
+
+#define to_zynq_pll_clk(hw) container_of(hw, struct zynq_pll_clk, hw)
+
+#define CTRL_PLL_FDIV(x) ((x) >> 12)
+
+static unsigned long zynq_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct zynq_pll_clk *pll = to_zynq_pll_clk(hw);
+ return parent_rate * CTRL_PLL_FDIV(ioread32(pll->pll_ctrl));
+}
+
+static const struct clk_ops zynq_pll_clk_ops = {
+ .recalc_rate = zynq_pll_recalc_rate,
+};
+
+static void __init zynq_pll_clk_setup(struct device_node *np)
+{
+ struct clk_init_data init;
+ struct zynq_pll_clk *pll;
+ const char *parent_name;
+ struct clk *clk;
+ u32 regs[2];
+ int ret;
+
+ ret = of_property_read_u32_array(np, "reg", regs, ARRAY_SIZE(regs));
+ if (WARN_ON(ret))
+ return;
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (WARN_ON(!pll))
+ return;
+
+ pll->pll_ctrl = slcr_base + regs[0];
+ pll->pll_cfg = slcr_base + regs[1];
+
+ of_property_read_string(np, "clock-output-names", &init.name);
+
+ init.ops = &zynq_pll_clk_ops;
+ parent_name = of_clk_get_parent_name(np, 0);
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ pll->hw.init = &init;
+
+ clk = clk_register(NULL, &pll->hw);
+ if (WARN_ON(IS_ERR(clk)))
+ return;
+
+ ret = of_clk_add_provider(np, of_clk_src_simple_get, clk);
+ if (WARN_ON(ret))
+ return;
+}
+
+struct zynq_periph_clk {
+ struct clk_hw hw;
+ struct clk_onecell_data onecell_data;
+ struct clk *gates[2];
+ void __iomem *clk_ctrl;
+ spinlock_t clkact_lock;
+};
+
+#define to_zynq_periph_clk(hw) container_of(hw, struct zynq_periph_clk, hw)
+
+static const u8 periph_clk_parent_map[] = {
+ 0, 0, 1, 2
+};
+#define PERIPH_CLK_CTRL_SRC(x) (periph_clk_parent_map[((x) & 0x30) >> 4])
+#define PERIPH_CLK_CTRL_DIV(x) (((x) & 0x3F00) >> 8)
+
+static unsigned long zynq_periph_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct zynq_periph_clk *periph = to_zynq_periph_clk(hw);
+ return parent_rate / PERIPH_CLK_CTRL_DIV(ioread32(periph->clk_ctrl));
+}
+
+static u8 zynq_periph_get_parent(struct clk_hw *hw)
+{
+ struct zynq_periph_clk *periph = to_zynq_periph_clk(hw);
+ return PERIPH_CLK_CTRL_SRC(ioread32(periph->clk_ctrl));
+}
+
+static const struct clk_ops zynq_periph_clk_ops = {
+ .recalc_rate = zynq_periph_recalc_rate,
+ .get_parent = zynq_periph_get_parent,
+};
+
+static void __init zynq_periph_clk_setup(struct device_node *np)
+{
+ struct zynq_periph_clk *periph;
+ const char *parent_names[3];
+ struct clk_init_data init;
+ int clk_num = 0, err;
+ const char *name;
+ struct clk *clk;
+ u32 reg;
+ int i;
+
+ err = of_property_read_u32(np, "reg", &reg);
+ if (WARN_ON(err))
+ return;
+
+ periph = kzalloc(sizeof(*periph), GFP_KERNEL);
+ if (WARN_ON(!periph))
+ return;
+
+ periph->clk_ctrl = slcr_base + reg;
+ spin_lock_init(&periph->clkact_lock);
+
+ init.name = np->name;
+ init.ops = &zynq_periph_clk_ops;
+ for (i = 0; i < ARRAY_SIZE(parent_names); i++)
+ parent_names[i] = of_clk_get_parent_name(np, i);
+ init.parent_names = parent_names;
+ init.num_parents = ARRAY_SIZE(parent_names);
+
+ periph->hw.init = &init;
+
+ clk = clk_register(NULL, &periph->hw);
+ if (WARN_ON(IS_ERR(clk)))
+ return;
+
+ err = of_clk_add_provider(np, of_clk_src_simple_get, clk);
+ if (WARN_ON(err))
+ return;
+
+ err = of_property_read_string_index(np, "clock-output-names", 0,
+ &name);
+ if (WARN_ON(err))
+ return;
+
+ periph->gates[0] = clk_register_gate(NULL, name, np->name, 0,
+ periph->clk_ctrl, 0, 0,
+ &periph->clkact_lock);
+ if (WARN_ON(IS_ERR(periph->gates[0])))
+ return;
+ clk_num++;
+
+ /* some periph clks have 2 downstream gates */
+ err = of_property_read_string_index(np, "clock-output-names", 1,
+ &name);
+ if (err != -ENODATA) {
+ periph->gates[1] = clk_register_gate(NULL, name, np->name, 0,
+ periph->clk_ctrl, 1, 0,
+ &periph->clkact_lock);
+ if (WARN_ON(IS_ERR(periph->gates[1])))
+ return;
+ clk_num++;
+ }
+
+ periph->onecell_data.clks = periph->gates;
+ periph->onecell_data.clk_num = clk_num;
+
+ err = of_clk_add_provider(np, of_clk_src_onecell_get,
+ &periph->onecell_data);
+ if (WARN_ON(err))
+ return;
+}
+
+/* CPU Clock domain is modelled as a mux with 4 children subclks, whose
+ * derivative rates depend on CLK_621_TRUE
+ */
+
+struct zynq_cpu_clk {
+ struct clk_hw hw;
+ struct clk_onecell_data onecell_data;
+ struct clk *subclks[4];
+ void __iomem *clk_ctrl;
+ spinlock_t clkact_lock;
+};
+
+#define to_zynq_cpu_clk(hw) container_of(hw, struct zynq_cpu_clk, hw)
+
+static const u8 zynq_cpu_clk_parent_map[] = {
+ 1, 1, 2, 0
+};
+#define CPU_CLK_SRCSEL(x) (zynq_cpu_clk_parent_map[(((x) & 0x30) >> 4)])
+#define CPU_CLK_CTRL_DIV(x) (((x) & 0x3F00) >> 8)
+
+static u8 zynq_cpu_clk_get_parent(struct clk_hw *hw)
+{
+ struct zynq_cpu_clk *cpuclk = to_zynq_cpu_clk(hw);
+ return CPU_CLK_SRCSEL(ioread32(cpuclk->clk_ctrl));
+}
+
+static unsigned long zynq_cpu_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct zynq_cpu_clk *cpuclk = to_zynq_cpu_clk(hw);
+ return parent_rate / CPU_CLK_CTRL_DIV(ioread32(cpuclk->clk_ctrl));
+}
+
+static const struct clk_ops zynq_cpu_clk_ops = {
+ .get_parent = zynq_cpu_clk_get_parent,
+ .recalc_rate = zynq_cpu_clk_recalc_rate,
+};
+
+struct zynq_cpu_subclk {
+ struct clk_hw hw;
+ void __iomem *clk_621;
+ enum {
+ CPU_SUBCLK_6X4X,
+ CPU_SUBCLK_3X2X,
+ CPU_SUBCLK_2X,
+ CPU_SUBCLK_1X,
+ } which;
+};
+
+#define CLK_621_TRUE(x) ((x) & 1)
+
+#define to_zynq_cpu_subclk(hw) container_of(hw, struct zynq_cpu_subclk, hw);
+
+static unsigned long zynq_cpu_subclk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ unsigned long uninitialized_var(rate);
+ struct zynq_cpu_subclk *subclk;
+ bool is_621;
+
+ subclk = to_zynq_cpu_subclk(hw)
+ is_621 = CLK_621_TRUE(ioread32(subclk->clk_621));
+
+ switch (subclk->which) {
+ case CPU_SUBCLK_6X4X:
+ rate = parent_rate;
+ break;
+ case CPU_SUBCLK_3X2X:
+ rate = parent_rate / 2;
+ break;
+ case CPU_SUBCLK_2X:
+ rate = parent_rate / (is_621 ? 3 : 2);
+ break;
+ case CPU_SUBCLK_1X:
+ rate = parent_rate / (is_621 ? 6 : 4);
+ break;
+ };
+
+ return rate;
+}
+
+static const struct clk_ops zynq_cpu_subclk_ops = {
+ .recalc_rate = zynq_cpu_subclk_recalc_rate,
+};
+
+static struct clk *zynq_cpu_subclk_setup(struct device_node *np, u8 which,
+ void __iomem *clk_621)
+{
+ struct zynq_cpu_subclk *subclk;
+ struct clk_init_data init;
+ struct clk *clk;
+ int err;
+
+ err = of_property_read_string_index(np, "clock-output-names",
+ which, &init.name);
+ if (WARN_ON(err))
+ goto err_read_output_name;
+
+ subclk = kzalloc(sizeof(*subclk), GFP_KERNEL);
+ if (!subclk)
+ goto err_subclk_alloc;
+
+ subclk->clk_621 = clk_621;
+ subclk->which = which;
+
+ init.ops = &zynq_cpu_subclk_ops;
+ init.parent_names = &np->name;
+ init.num_parents = 1;
+
+ subclk->hw.init = &init;
+
+ clk = clk_register(NULL, &subclk->hw);
+ if (WARN_ON(IS_ERR(clk)))
+ goto err_clk_register;
+
+ return clk;
+
+err_clk_register:
+ kfree(subclk);
+err_subclk_alloc:
+err_read_output_name:
+ return ERR_PTR(-EINVAL);
+}
+
+static void __init zynq_cpu_clk_setup(struct device_node *np)
+{
+ struct zynq_cpu_clk *cpuclk;
+ const char *parent_names[3];
+ struct clk_init_data init;
+ void __iomem *clk_621;
+ struct clk *clk;
+ u32 reg[2];
+ int err;
+ int i;
+
+ err = of_property_read_u32_array(np, "reg", reg, ARRAY_SIZE(reg));
+ if (WARN_ON(err))
+ return;
+
+ cpuclk = kzalloc(sizeof(*cpuclk), GFP_KERNEL);
+ if (WARN_ON(!cpuclk))
+ return;
+
+ cpuclk->clk_ctrl = slcr_base + reg[0];
+ clk_621 = slcr_base + reg[1];
+ spin_lock_init(&cpuclk->clkact_lock);
+
+ init.name = np->name;
+ init.ops = &zynq_cpu_clk_ops;
+ for (i = 0; i < ARRAY_SIZE(parent_names); i++)
+ parent_names[i] = of_clk_get_parent_name(np, i);
+ init.parent_names = parent_names;
+ init.num_parents = ARRAY_SIZE(parent_names);
+
+ cpuclk->hw.init = &init;
+
+ clk = clk_register(NULL, &cpuclk->hw);
+ if (WARN_ON(IS_ERR(clk)))
+ return;
+
+ err = of_clk_add_provider(np, of_clk_src_simple_get, clk);
+ if (WARN_ON(err))
+ return;
+
+ for (i = 0; i < 4; i++) {
+ cpuclk->subclks[i] = zynq_cpu_subclk_setup(np, i, clk_621);
+ if (WARN_ON(IS_ERR(cpuclk->subclks[i])))
+ return;
+ }
+
+ cpuclk->onecell_data.clks = cpuclk->subclks;
+ cpuclk->onecell_data.clk_num = i;
+
+ err = of_clk_add_provider(np, of_clk_src_onecell_get,
+ &cpuclk->onecell_data);
+ if (WARN_ON(err))
+ return;
+}
+
+static const __initconst struct of_device_id zynq_clk_match[] = {
+ { .compatible = "fixed-clock", .data = of_fixed_clk_setup, },
+ { .compatible = "xlnx,zynq-pll", .data = zynq_pll_clk_setup, },
+ { .compatible = "xlnx,zynq-periph-clock",
+ .data = zynq_periph_clk_setup, },
+ { .compatible = "xlnx,zynq-cpu-clock", .data = zynq_cpu_clk_setup, },
+ {}
+};
+
+void __init xilinx_zynq_clocks_init(void __iomem *slcr)
+{
+ slcr_base = slcr;
+ of_clk_init(zynq_clk_match);
+}
OpenPOWER on IntegriCloud