clk: sunxi: Add support for AXI, AHB, APB0 and APB1 gates

This patchset adds DT support for all the AXI, AHB, APB0 and APB1
gates present on sunxi SoCs.

Signed-off-by: Emilio López <emilio@elopez.com.ar>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

1 files changed, 88 insertions, 0 deletions

diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c
index d528a2496690..244de90d5360 100644
--- a/drivers/clk/sunxi/clk-sunxi.c
+++ b/drivers/clk/sunxi/clk-sunxi.c
@@ -302,6 +302,82 @@ static void __init sunxi_divider_clk_setup(struct device_node *node,
 }
 
 
+
+/**
+ * sunxi_gates_clk_setup() - Setup function for leaf gates on clocks
+ */
+
+#define SUNXI_GATES_MAX_SIZE    64
+
+struct gates_data {
+        DECLARE_BITMAP(mask, SUNXI_GATES_MAX_SIZE);
+};
+
+static const __initconst struct gates_data axi_gates_data = {
+        .mask = {1},
+};
+
+static const __initconst struct gates_data ahb_gates_data = {
+        .mask = {0x7F77FFF, 0x14FB3F},
+};
+
+static const __initconst struct gates_data apb0_gates_data = {
+        .mask = {0x4EF},
+};
+
+static const __initconst struct gates_data apb1_gates_data = {
+        .mask = {0xFF00F7},
+};
+
+static void __init sunxi_gates_clk_setup(struct device_node *node,
+                                         struct gates_data *data)
+{
+        struct clk_onecell_data *clk_data;
+        const char *clk_parent;
+        const char *clk_name;
+        void *reg;
+        int qty;
+        int i = 0;
+        int j = 0;
+        int ignore;
+
+        reg = of_iomap(node, 0);
+
+        clk_parent = of_clk_get_parent_name(node, 0);
+
+        /* Worst-case size approximation and memory allocation */
+        qty = find_last_bit(data->mask, SUNXI_GATES_MAX_SIZE);
+        clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
+        if (!clk_data)
+                return;
+        clk_data->clks = kzalloc((qty+1) * sizeof(struct clk *), GFP_KERNEL);
+        if (!clk_data->clks) {
+                kfree(clk_data);
+                return;
+        }
+
+        for_each_set_bit(i, data->mask, SUNXI_GATES_MAX_SIZE) {
+                of_property_read_string_index(node, "clock-output-names",
+                                              j, &clk_name);
+
+                /* No driver claims this clock, but it should remain gated */
+                ignore = !strcmp("ahb_sdram", clk_name) ? CLK_IGNORE_UNUSED : 0;
+
+                clk_data->clks[i] = clk_register_gate(NULL, clk_name,
+                                                      clk_parent, ignore,
+                                                      reg + 4 * (i/32), i % 32,
+                                                      0, &clk_lock);
+                WARN_ON(IS_ERR(clk_data->clks[i]));
+
+                j++;
+        }
+
+        /* Adjust to the real max */
+        clk_data->clk_num = i;
+
+        of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
+}
+
 /* Matches for of_clk_init */
 static const __initconst struct of_device_id clk_match[] = {
         {.compatible = "fixed-clock", .data = of_fixed_clk_setup,},
@@ -331,6 +407,15 @@ static const __initconst struct of_device_id clk_mux_match[] = {
         {}
 };
 
+/* Matches for gate clocks */
+static const __initconst struct of_device_id clk_gates_match[] = {
+        {.compatible = "allwinner,sun4i-axi-gates-clk", .data = &axi_gates_data,},
+        {.compatible = "allwinner,sun4i-ahb-gates-clk", .data = &ahb_gates_data,},
+        {.compatible = "allwinner,sun4i-apb0-gates-clk", .data = &apb0_gates_data,},
+        {.compatible = "allwinner,sun4i-apb1-gates-clk", .data = &apb1_gates_data,},
+        {}
+};
+
 static void __init of_sunxi_table_clock_setup(const struct of_device_id *clk_match,
                                               void *function)
 {
@@ -359,4 +444,7 @@ void __init sunxi_init_clocks(void)
 
         /* Register mux clocks */
         of_sunxi_table_clock_setup(clk_mux_match, sunxi_mux_clk_setup);
+
+        /* Register gate clocks */
+        of_sunxi_table_clock_setup(clk_gates_match, sunxi_gates_clk_setup);
 }