clk: ti: Add support for dm814x ADPLL

On dm814x we have 13 ADPLLs with 3 to 4 outputs on each. The
ADPLLs have several dividers and muxes controlled by a shared
control register for each PLL.

Note that for the clocks to work as device drivers for booting on
dm814x, this patch depends on "ARM: OMAP2+: Change core_initcall
levels to postcore_initcall" that has already been merged.

Also note that this patch does not implement clk_set_rate for the
PLL, that will be posted later on when available.

Cc: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>

1 files changed, 53 insertions, 0 deletions

diff --git a/drivers/clk/ti/clk-814x.c b/drivers/clk/ti/clk-814x.c
index 9e85fcc74cc9..2323643fb731 100644
--- a/drivers/clk/ti/clk-814x.c
+++ b/drivers/clk/ti/clk-814x.c
@@ -5,8 +5,10 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/clk/ti.h>
+#include <linux/of_platform.h>
 
 #include "clock.h"
 
@@ -27,11 +29,62 @@ static struct ti_dt_clk dm814_clks[] = {
 	{ .node_name = NULL },
 };
 
+static bool timer_clocks_initialized;
+
+int __init dm814x_adpll_early_init(void)
+{
+	struct device_node *np;
+
+	if (!timer_clocks_initialized)
+		return -ENODEV;
+
+	np = of_find_node_by_name(NULL, "pllss");
+	if (!np) {
+		pr_err("Could not find node for plls\n");
+		return -ENODEV;
+	}
+
+	of_platform_populate(np, NULL, NULL, NULL);
+
+	return 0;
+}
+core_initcall(dm814x_adpll_early_init);
+
+static const char * const init_clocks[] = {
+	"pll040clkout",		/* MPU 481c5040.adpll.clkout */
+	"pll290clkout",		/* DDR 481c5290.adpll.clkout */
+};
+
+int __init dm814x_adpll_enable_init_clocks(void)
+{
+	int i, err;
+
+	if (!timer_clocks_initialized)
+		return -ENODEV;
+
+	for (i = 0; i < ARRAY_SIZE(init_clocks); i++) {
+		struct clk *clock;
+
+		clock = clk_get(NULL, init_clocks[i]);
+		if (WARN(IS_ERR(clock), "could not find init clock %s\n",
+			 init_clocks[i]))
+			continue;
+		err = clk_prepare_enable(clock);
+		if (WARN(err, "could not enable init clock %s\n",
+			 init_clocks[i]))
+			continue;
+	}
+
+	return 0;
+}
+postcore_initcall(dm814x_adpll_enable_init_clocks);
+
 int __init dm814x_dt_clk_init(void)
 {
 	ti_dt_clocks_register(dm814_clks);
 	omap2_clk_disable_autoidle_all();
 	omap2_clk_enable_init_clocks(NULL, 0);
+	timer_clocks_initialized = true;
 
 	return 0;
 }